kemonine/emacs
Archived
1
0
Fork 0
Code Activity
This repository has been archived on 2024-10-19. You can view files and clone it, but cannot push or open issues or pull requests.
emacs/code/elpa/web-server-20210708.2242/web-server.info

2107 lines
97 KiB
Plaintext
Raw Normal View History

update packages / add markdown preview mode packages
2022-08-25 15:13:38 +00:00
This is web-server.info, produced by makeinfo version 6.7 from
web-server.texi.
This file documents the Emacs Web Server (web-server)
Copyright (C) 2013 Eric Schulte <schulte.eric@gmail.com>
Permission is granted to copy, distribute and/or modify this
document under the terms of the GNU Free Documentation License,
Version 1.3 or any later version published by the Free Software
Foundation; with the Invariant Section being “GNU GENERAL PUBLIC
LICENSE,” A copy of the license is included in the section entitled
“GNU Free Documentation License.”
INFO-DIR-SECTION Emacs
START-INFO-DIR-ENTRY
* Web Server: (web-server). Web Server for Emacs.
END-INFO-DIR-ENTRY

File: web-server.info, Node: Top, Next: Introduction, Prev: (dir), Up: (dir)
Emacs Web Server User Manual
****************************
This file documents the Emacs Web Server (web-server)
Copyright (C) 2013 Eric Schulte <schulte.eric@gmail.com>
Permission is granted to copy, distribute and/or modify this
document under the terms of the GNU Free Documentation License,
Version 1.3 or any later version published by the Free Software
Foundation; with the Invariant Section being “GNU GENERAL PUBLIC
LICENSE,” A copy of the license is included in the section entitled
“GNU Free Documentation License.”
* Menu:
* Introduction:: Overview of the Emacs Web Server
* Handlers:: Handlers respond to HTTP requests
* Requests:: Getting information on HTTP requests
* Usage Examples:: Examples demonstrating usage
* Function Index:: List of Functions
Appendices
* Copying:: The GNU General Public License gives
you permission to redistribute GNU Emacs on
certain terms; it also explains that there is
no warranty.
* GNU Free Documentation License:: The license for this documentation.
* Index:: Complete index.

File: web-server.info, Node: Introduction, Next: Handlers, Prev: Top, Up: Top
1 Introduction
**************
The Emacs Web Server is a Web server implemented entirely in Emacs Lisp.
HTTP requests are matched to handlers (*note Handlers::) which are Emacs
Lisp functions. Handlers receive as their only argument a request
object (*note Requests::) which holds information about the request and
a process holding the HTTP network connection. Handlers write their
responses directly to the network process.
A number of examples (*note Usage Examples::) demonstrate usage of
the Emacs Web Server. All public functions of the Emacs Web Server are
listed (*note Function Index::).

File: web-server.info, Node: Handlers, Next: Requests, Prev: Handlers, Up: Top
2 Handlers
**********
The function ‘ws-start’ takes takes two arguments ‘handlers’ and ‘port’.
It starts a server listening on ‘port’ responding to requests with
‘handlers’. ‘Handlers’ may be either a single function or an
association list composed of pairs of matchers and handler functions.
When ‘handlers’ is a single function the given function is used to serve
every request, when it is an association list, the function of the first
matcher to match each request handles that request.
2.1 Matchers
============
Matchers may be a regular expression or a function. Regular expression
matchers consists of an HTTP header and a regular expression. When the
regular expression matches the content of the given header the matcher
succeeds and the associated handler is called. For example the
following matches any ‘GET’ request whose path starts with the substring
“foo”.
(:GET . "^foo")
A function matcher is a function which takes the request object
(*note Requests::) and succeeds when the function returns a non-nil
value. For example the following matcher matches every request,
(lambda (_) t)
and the following matches only requests in which the supplied
“number” parameter is odd.
(lambda (request)
(oddp (string-to-number (cdr (assoc "number" request)))))
2.2 Handler Function
====================
Each handler is a function which takes a request object (*note
Requests::) as its only argument. The function may respond to the
request by writing to the network process held in the ‘process’ field of
the request object. For example, the ‘process-send-string’ function may
be used to write string data to a request as in the following.
(process-send-string (process request) "hello world")
When the handler function exits the connection is terminated unless
the handler function returns the keyword ‘:keep-alive’.

File: web-server.info, Node: Requests, Next: Usage Examples, Prev: Handlers, Up: Top
3 Requests
**********
Each HTTP requests is represented using a ‘ws-request’ object (*note
ws-request::). The request object serves two purposes, one internal and
one external. Internally, request objects are used to hold state while
HTTP headers are parsed incrementally as the HTTP request text is
received from the network. Externally, request objects are used to
decide which handler to call, and are then passed as the only argument
to the called handler.
In addition to fields used internally, each ‘ws-request’ object holds
the network process in the ‘process’ and holds all HTTP headers and
request GET or POST parameters in the ‘headers’ alist. HTML Headers are
keyed using uppercase keywords (e.g., ‘:GET’), and user supplied
parameters are keyed using the string name of the parameter.
The ‘process’ field may be used by handlers to send data to a client
as in the following example.
(process-send-string (process request) "hello world")
The ‘headers’ field may be used to access request information such as
the requested path,
(cdr (assoc :GET (headers request)))
or named parameters as from a web form.
(cdr (assoc "message" (headers request)))

File: web-server.info, Node: Usage Examples, Next: Hello World, Prev: Requests, Up: Top
4 Usage Examples
****************
These examples demonstrate usage.
* Menu:
* Hello World:: Serve “Hello World” to every request
* Hello World UTF8:: Serve “Hello World” w/UTF8 encoding
* Hello World HTML:: Serve “Hello World” in HTML
* File Server:: Serve files from a document root
* URL Parameter Echo:: Echo parameters from a URL query string
* POST Echo:: Echo POST parameters back
* Basic Authentication:: BASIC HTTP authentication
* Org-mode Export:: Export files to HTML and Tex
* File Upload:: Upload files and return their sha1sum
* Web Socket:: Web socket echo server
* Gzipped Transfer Encoding:: Gzip content encoding
* Chunked Transfer Encoding:: Chunked transfer encoding

File: web-server.info, Node: Hello World, Next: Hello World UTF8, Prev: Usage Examples, Up: Usage Examples
4.1 Hello World
===============
The simplest possible “hello world” example. The handler consists of a
single (matcher . handler) pair. The function matcher matches _every_
incoming HTTP request. The handler responds by setting the content type
to ‘text/plain’, and then sending the string “hello world”. When the
handler exits the network connection of the request is closed.
;;; hello-world.el --- simple hello world server using Emacs Web Server
;; Copyright (C) 2014 Free Software Foundation, Inc.
(ws-start
(lambda (request)
(with-slots (process headers) request
(ws-response-header process 200 '("Content-type" . "text/plain"))
(process-send-string process "hello world")))
9000)

File: web-server.info, Node: Hello World UTF8, Next: Hello World HTML, Prev: Hello World, Up: Usage Examples
4.2 Hello World UTF8
====================
This example only differs from the previous in that the “Content-type”
indicates UTF8 encoded data, and the hello world sent is selected at
random from a list of different languages.
;;; hello-world-utf8.el --- utf8 hello world server using Emacs Web Server
;; Copyright (C) 2014 Free Software Foundation, Inc.
(ws-start
(lambda (request)
(with-slots (process headers) request
(let ((hellos '("こんにちは"
"안녕하세요"
"góðan dag"
"Grüßgott"
"hyvää päivää"
"yá'át'ééh"
"Γεια σας"
"Вiтаю"
"გამარჯობა"
"नमस्ते"
"你好")))
(ws-response-header process 200
'("Content-type" . "text/plain; charset=utf-8"))
(process-send-string process
(concat (nth (random (length hellos)) hellos) " world")))))
9001)

File: web-server.info, Node: Hello World HTML, Next: File Server, Prev: Hello World UTF8, Up: Usage Examples
4.3 Hello World HTML
====================
;;; hello-world-html.el --- html hello world server using Emacs Web Server
;; Copyright (C) 2014 Free Software Foundation, Inc.
(ws-start
(lambda (request)
(with-slots (process headers) request
(ws-response-header process 200 '("Content-type" . "text/html"))
(process-send-string process "<html>
<head>
<title>Hello World</title>
</head>
<body>
<b>hello world</b>
</body>
</html>")))
9002)
This variation of the “hello world” example sends a ‘text/html’
response instead of a simple ‘text/plain’ response.

File: web-server.info, Node: File Server, Next: URL Parameter Echo, Prev: Hello World HTML, Up: Usage Examples
4.4 File Server
===============
The following example implements a file server which will serve files
from the ‘docroot’ document root set to the current working directory in
this example. Four helper functions are used; ‘ws-in-directory-p’ is
used to check if the requested path is within the document root. If not
then ‘ws-send-404’ is used to send a default “File Not Found”. If so
then the file is served with ‘ws-send-file’ (which appropriately sets
the mime-type of the response based on the extension of the file) if it
is a file or is served with ‘ws-send-directory-list’ if it is a
directory.
;;; file-server.el --- serve any files using Emacs Web Server
;; Copyright (C) 2014 Free Software Foundation, Inc.
(lexical-let ((docroot default-directory))
(ws-start
(lambda (request)
(with-slots (process headers) request
(let ((path (substring (cdr (assoc :GET headers)) 1)))
(if (ws-in-directory-p docroot path)
(if (file-directory-p path)
(ws-send-directory-list process
(expand-file-name path docroot) "^[^\.]")
(ws-send-file process (expand-file-name path docroot)))
(ws-send-404 process)))))
9003))

File: web-server.info, Node: URL Parameter Echo, Next: POST Echo, Prev: File Server, Up: Usage Examples
4.5 URL Parameter Echo
======================
This example demonstrates access of URL-encoded parameters in a ‘GET’
request. For example the following URL
<http://localhost:9005/example?foo=bar&baz=qux> will render as the
following HTML table.
foo bar
baz qux
;;; url-param-echo.el --- echo back url-paramed message using Emacs Web Server
;; Copyright (C) 2014 Free Software Foundation, Inc.
(ws-start
'(((:GET . ".*") .
(lambda (request)
(with-slots (process headers) request
(ws-response-header process 200 '("Content-type" . "text/html"))
(process-send-string process
(concat "URL Parameters:</br><table><tr>"
(mapconcat (lambda (pair)
(format "<th>%s</th><td>%s</td>"
(car pair) (cdr pair)))
(cl-remove-if-not (lambda (el) (stringp (car el)))
headers)
"</tr><tr>")
"</tr></table>"))))))
9004)

File: web-server.info, Node: POST Echo, Next: Basic Authentication, Prev: URL Parameter Echo, Up: Usage Examples
4.6 POST Echo
=============
The following example echos back the content of the “message” field in a
‘POST’ request.
;;; post-echo.el --- echo back posted message using Emacs Web Server
;; Copyright (C) 2014 Free Software Foundation, Inc.
(ws-start
'(((:POST . ".*") .
(lambda (request)
(with-slots (process headers) request
(let ((message (cdr (assoc "message" headers))))
(ws-response-header process 200 '("Content-type" . "text/plain"))
(process-send-string process
(if message
(format "you said %S\n" (cdr (assoc 'content message)))
"This is a POST request, but it has no \"message\".\n"))))))
((:GET . ".*") .
(lambda (request)
(with-slots (process) request
(ws-response-header process 200 '("Content-type" . "text/plain"))
(process-send-string process
"This is a GET request not a POST request.\n")))))
9005)

File: web-server.info, Node: Basic Authentication, Next: Org-mode Export, Prev: POST Echo, Up: Usage Examples
4.7 Basic Authentication
========================
The following example demonstrates BASIC HTTP authentication. The
handler prompts an unauthenticated client for authentication by sending
a “WWW-Authenticate” header.
(ws-response-header process 401
'("WWW-Authenticate" . "Basic realm=\"example\"")
'("Content-type" . "text/plain"))
The client replies by setting the “Authorization” HTTP header which
is parsed into a list of the form ‘(PROTOCOL USERNAME . PASSWORD)’.
Currently only BASIC HTTP authentication is supported.
Note: BASIC HTTP authentication passes user credentials in plain text
between the client and the server and should generally only be used with
HTTPS network encryption. While the Emacs web server currently doesn’t
support HTTPS network encryption it may be run behind an HTTPS proxy
server (e.g., Apache or Nginx) with HTTPS support.
;;; basic-authentication.el --- basic authentication
;; Copyright (C) 2014 Free Software Foundation, Inc.
(lexical-let ((users '(("foo" . "bar")
("baz" . "qux"))))
(ws-start
(ws-with-authentication
(lambda (request)
(with-slots (process headers) request
(let ((user (caddr (assoc :AUTHORIZATION headers))))
(ws-response-header process 200 '("Content-type" . "text/plain"))
(process-send-string process (format "welcome %s" user)))))
users)
9006))

File: web-server.info, Node: Org-mode Export, Next: File Upload, Prev: Basic Authentication, Up: Usage Examples
4.8 Org-mode Export
===================
The following example exports a directory of Org-mode files as either
text, HTML or LaTeX. The Org-mode export engine is used to export files
on-demand as they are requested.
;;; org-mode-file-server.el --- serve on-demand exported Org-mode files
;; Copyright (C) 2014 Free Software Foundation, Inc.
(lexical-let ((docroot "/tmp/"))
(ws-start
(lambda (request)
(with-slots (process headers) request
(let ((path (ws-in-directory-p ; check if path is in docroot
docroot (substring (cdr (assoc :GET headers)) 1))))
(unless path (ws-send-404 process)) ; send 404 if not in docroot
(if (file-directory-p path)
(progn ;; send directory listing, convert org files to html/tex/txt
(ws-response-header proc 200 (cons "Content-type" "text/html"))
(process-send-string proc
(concat "<ul>"
(mapconcat
(lambda (f)
(let* ((full (expand-file-name f path))
(end (if (file-directory-p full) "/" ""))
(url (url-encode-url (concat f end))))
(format "<li><a href=%s>%s</li>" url f)))
(apply #'append
(mapcar
(lambda (f)
(list (concat f ".txt")
(concat f ".tex")
(concat f ".html")))
(mapcar #'file-name-sans-extension
(directory-files path nil
"^[^\.].*org$"))))
"\n") "</ul>")))
;; Export the file as requested and return the result
(let* ((base (file-name-sans-extension path))
(type (case (intern (downcase (file-name-extension path)))
(html 'html)
(tex 'latex)
(txt 'ascii)
(t (ws-error process "%S export not supported"
(file-name-extension path)))))
(orig (concat base ".org")))
(unless (file-exists-p orig) (ws-send-404 process))
(save-window-excursion (find-file orig)
(org-export-to-file type path))
(ws-send-file process path))))))
9007))

File: web-server.info, Node: File Upload, Next: Web Socket, Prev: Org-mode Export, Up: Usage Examples
4.9 File Upload
===============
The following example demonstrates accessing an uploaded file. This
simple server accesses the file named “file” and returns it’s sha1sum
and file name.
;;; file-upload.el --- use an uploaded file
;; Copyright (C) 2014 Free Software Foundation, Inc.
(ws-start
'(((:POST . ".*") .
(lambda (request)
(with-slots (process headers) request
(ws-response-header process 200 '("Content-type" . "text/plain"))
(let ((file (cdr (assoc "file" headers))))
(process-send-string process
(concat (sha1 (cdr (assoc 'content file))) " "
(cdr (assoc 'filename file)) "\n")))))))
9008)
A file may be uploaded from an HTML form, or using the ‘curl’ program
as in the following example.
$ curl -s -F file=usr/share/emacs/24.3/etc/COPYING localhost:9008
8624bcdae55baeef00cd11d5dfcfa60f68710a02 COPYING
$ sha1sum /usr/share/emacs/24.3/etc/COPYING
8624bcdae55baeef00cd11d5dfcfa60f68710a02 /usr/share/emacs/24.3/etc/COPYING

File: web-server.info, Node: Web Socket, Next: Chunked Transfer Encoding, Prev: File Upload, Up: Usage Examples
4.10 Web Socket
===============
Example demonstrating the use of web sockets for full duplex
communication between clients and the server. Handlers may use the
‘ws-web-socket-connect’ function (*note ws-web-socket-connect::) to
check for and respond to a web socket upgrade request sent by the client
(as demonstrated with the ‘new WebSocket’ JavaScript code in the
example). Upon successfully initializing a web socket connection the
call to ‘ws-web-socket-connect’ will return the web socket network
process. This process may then be used by the server to communicate
with the client over the web socket using the ‘process-send-string’ and
‘ws-web-socket-frame’ functions. All web socket communication must be
wrapped in frames using the ‘ws-web-socket-frame’ function.
The handler must pass a function as the second argument to
‘ws-web-socket-connect’. This function will be called on every web
socket message received from the client.
Note: in order to keep the web socket connection alive the request
handler from which ‘ws-web-socket-connect’ is called must return the
‘:keep-alive’ keyword, as demonstrated in the example.
;;; web-sockets.el --- communicate via web-sockets
;; Copyright (C) 2014 Free Software Foundation, Inc.
(lexical-let* ((web-socket-port 9009)
(web-socket-page
(format "<html>
<head>
<script type=\"text/javascript\">
var ws;
function connect(){
ws = new WebSocket(\"ws://localhost:%d/\");
ws.onopen = function() { alert(\"connected\"); };
ws.onmessage = function(msg) { alert(\"server: \" + msg.data); };
ws.onclose = function() { alert(\"connection closed\"); };
}
function message(){ ws.send(\"foo\"); }
function close(){ ws.close(); };
</script>
</head>
<body>
<ol>
<li>Press \"connect\" to initialize the web socket connection to
the server. The server will complete the web socket
handshake at which point you'll see an alert with the text
\"connected\".</li>
<li>Press \"message\" to send the string \"foo\" to the server.
The server will reply with the text \"you said: foo\" which
you will see in an alert as \"server: you said: foo\".</li>
<li>Press \"close\" to close the connection. After the server
responds with a close frame you will see an alert with the
text \"connection closed\".</li>
</ol>
<a href=\"javascript:connect()\">connect</a>
<a href=\"javascript:message()\">message</a>
<a href=\"javascript:close()\">close</a>
</body>
</html>" web-socket-port)))
(ws-start
(lambda (request)
(with-slots (process headers) request
;; if a web-socket request, then connect and keep open
(if (ws-web-socket-connect request
(lambda (proc string)
(process-send-string proc
(ws-web-socket-frame (concat "you said: " string)))))
(prog1 :keep-alive (setq my-connection process))
;; otherwise send the index page
(ws-response-header process 200 '("Content-type" . "text/html"))
(process-send-string process web-socket-page))))
web-socket-port))

File: web-server.info, Node: Gzipped Transfer Encoding, Next: Chunked Transfer Encoding, Prev: Web Socket, Up: Usage Examples
4.11 Gzipped Transfer Encoding
==============================
HTTP Responses may be compressed by setting the “gzip” (or “compress” or
“deflate”) content- or transfer-encoding HTTP headers in
‘ws-response-header’. Any further data sent to the process using
‘ws-send’ will automatically be appropriately compressed.
;;; content-encoding-gzip.el -- gzip content encoding
;; Copyright (C) 2014 Free Software Foundation, Inc.
(ws-start
(lambda (request)
(with-slots (process headers) request
(ws-response-header process 200
'("Content-type" . "text/plain; charset=utf-8")
'("Content-Encoding" . "x-gzip"))
(let ((s "Lorem ipsum dolor sit amet, consectetuer adipiscing elit. Donec
hendrerit tempor tellus. Donec pretium posuere tellus. Proin quam
nisl, tincidunt et, mattis eget, convallis nec, purus. Cum sociis
natoque penatibus et magnis dis parturient montes, nascetur
ridiculus mus. Nulla posuere. Donec vitae dolor. Nullam tristique
diam non turpis. Cras placerat accumsan nulla. Nullam rutrum. Nam
vestibulum accumsan nisl.
Lorem ipsum dolor sit amet, consectetuer adipiscing elit. Donec
hendrerit tempor tellus. Donec pretium posuere tellus. Proin quam
nisl, tincidunt et, mattis eget, convallis nec, purus. Cum sociis
natoque penatibus et magnis dis parturient montes, nascetur
ridiculus mus. Nulla posuere. Donec vitae dolor. Nullam tristique
diam non turpis. Cras placerat accumsan nulla. Nullam rutrum. Nam
vestibulum accumsan nisl."))
(ws-send process s))))
9016)

File: web-server.info, Node: Chunked Transfer Encoding, Next: Function Index, Prev: Web Socket, Up: Usage Examples
4.12 Chunked Transfer Encoding
==============================
Similarly, HTTP Responses may be sent using the “chunked” transfer
encoding by passing the appropriate HTTP header to ‘ws-response-header’.
Any further data sent to the process using ‘ws-send’ will automatically
be appropriately encoded for chunked transfer.
;;; transfer-encoding-chunked.el -- chunked transfer encoding
;; Copyright (C) 2014 Free Software Foundation, Inc.
(ws-start
(lambda (request)
(let ((s "
Lorem ipsum dolor sit amet, consectetuer adipiscing elit. Donec
hendrerit tempor tellus. Donec pretium posuere tellus. Proin quam
nisl, tincidunt et, mattis eget, convallis nec, purus. Cum sociis
natoque penatibus et magnis dis parturient montes, nascetur
ridiculus mus. Nulla posuere. Donec vitae dolor. Nullam tristique
diam non turpis. Cras placerat accumsan nulla. Nullam rutrum. Nam
vestibulum accumsan nisl.
Lorem ipsum dolor sit amet, consectetuer adipiscing elit. Donec
hendrerit tempor tellus. Donec pretium posuere tellus. Proin quam
nisl, tincidunt et, mattis eget, convallis nec, purus. Cum sociis
natoque penatibus et magnis dis parturient montes, nascetur
ridiculus mus. Nulla posuere. Donec vitae dolor. Nullam tristique
diam non turpis. Cras placerat accumsan nulla. Nullam rutrum. Nam
vestibulum accumsan nisl.
"))
(with-slots (process headers) request
(ws-response-header process 200
'("Content-type" . "text/plain; charset=utf-8")
'("Transfer-Encoding" . "chunked"))
(ws-send process s) (sit-for 0.5)
(ws-send process s) (sit-for 0.5)
(ws-send process s) (sit-for 0.5)
(ws-send process s))))
9017)

File: web-server.info, Node: Function Index, Next: Copying, Prev: Usage Examples, Up: Top
5 Function Index
****************
The following functions implement the Emacs Web Server public API.
5.1 Objects
===========
The following objects represent web servers and requests.
-- Class: ws-server handlers process port requests
Every Emacs web server is an instance of the ‘ws-server’ class.
Each instance includes the ‘handlers’ association list and ‘port’
passed to ‘ws-start’, as well as the server network ‘process’ and a
list of all active ‘requests’.
-- Class: ws-request process pending context boundary index active
headers
The ‘ws-request’ class represents an active web request. The
‘process’ field holds the network process of the client and may be
used by handlers to respond to requests. The ‘headers’ field holds
an alist of information on the request for use by handlers. The
remaining ‘pending’, ‘context’, ‘boundary’, ‘index’ and ‘active’
fields are used to maintain header parsing information across calls
to the ‘ws-filter’ function.
5.2 Starting and Stopping Servers
=================================
The following functions start and stop Emacs web servers. The
‘ws-servers’ list holds all running servers.
-- Function: ws-start handlers port &optional log-buffer &rest
network-args
‘ws-start’ starts a server listening on ‘port’ using ‘handlers’
(*note Handlers::) to match and respond to requests. An instance
of the ‘ws-server’ class is returned.
-- Variable: ws-servers
The ‘ws-servers’ list holds all active Emacs web servers.
-- Function: ws-stop server
‘ws-stop’ stops ‘server’ deletes all related processes, and frees
the server’s port. Evaluate the following to stop all emacs web
servers.
(mapc #'ws-stop ws-servers)
-- Function: ws-stop-all
‘ws-stop-all’ stops all emacs web servers by mapping ‘ws-stop’ over
‘ws-servers’.
5.3 Convenience Functions
=========================
The following convenience functions automate many common tasks
associated with responding to HTTP requests.
-- Function: ws-response-header process code &rest headers
Send the headers required to start an HTTP response to ‘proc’.
‘proc’ should be a ‘ws-request’ ‘proc’ of an active request.
For example start a standard 200 “OK” HTML response with the
following.
(ws-response-header process 200 '("Content-type" . "text/html"))
The encoding may optionally be set in the HTTP header. Send a UTF8
encoded response with the following.
(ws-response-header process 200
'("Content-type" . "text/plain; charset=utf-8"))
Additionally, when “Content-Encoding” or “Transfer-Encoding”
headers are supplied any subsequent data written to ‘proc’ using
‘ws-send’ will be encoded appropriately including sending the
appropriate data upon the end of transmission for chunked transfer
encoding.
For example with the header ‘("Content-Encoding" . "gzip")’, any
data subsequently written to ‘proc’ using ‘ws-send’ will be
compressed using the command specified in ‘ws-gzip-cmd’. See *note
Gzipped Transfer Encoding:: and *note Chunked Transfer Encoding::
for more complete examples.
-- Function: ws-send proc string
Send ‘string’ to process ‘proc’. If any Content or Transfer
encodings are in use, apply them to ‘string’ before sending.
-- Function: ws-send-500 process &rest msg-and-args
‘ws-send-500’ sends a default 500 “Internal Server Error” response
to ‘process’.
-- Function: ws-send-404 process &rest msg-and-args
‘ws-send-500’ sends a default 404 “File Not Found” response to
‘process’.
-- Function: ws-send-file process path &optional mime-type
‘ws-send-file’ sends the file located at ‘path’ to ‘process’. If
the optional ‘mime-type’ is not set, then the mime-type is
determined by calling ‘mm-default-file-encoding’ on ‘path’ or is
set to “application/octet-stream” if no mime-type can be
determined.
-- Function: ws-send-directory-list process directory &optional match
‘ws-send-directory-list’ sends the a listing of the files located
in ‘directory’ to ‘process’. The list is sent as an HTML list of
links to the files. Optional argument ‘match’ may be set to a
regular expression, in which case only those files that match are
listed.
-- Function: ws-in-directory-p parent path
Check if ‘path’ is under the ‘parent’ directory.
(ws-in-directory-p "/tmp/" "pics")
⇒ "/tmp/pics"
(ws-in-directory-p "/tmp/" "..")
⇒ nil
(ws-in-directory-p "/tmp/" "~/pics")
⇒ nil
-- Function: ws-with-authentication handler credentials &optional realm
unauth invalid
Return a version of ‘handler’ which is protected by ‘credentials’.
Handler should be a normal handler function (*note Handlers::) and
‘credentials’ should be an association list of usernames and
passwords.
For example, a server running the following handlers,
(list (cons '(:GET . ".*") 'view-handler)
(cons '(:POST . ".*") 'edit-handler))
could have authorization added by changing the handlers to the
following.
(list (cons '(:GET . ".*") view-handler)
(cons '(:POST . ".*") (ws-with-authentication
'org-ehtml-edit-handler
'(("admin" . "password")))))
-- Function: ws-web-socket-connect request handler
If ‘request’ is a web socket upgrade request (indicated by the
presence of the ‘:SEC-WEBSOCKET-KEY’ header argument) establish a
web socket connection to the client. Call ‘handler’ on web socket
messages received from the client.
(ws-web-socket-connect request
(lambda (proc string)
(process-send-string proc
(ws-web-socket-frame (concat "you said: " string)))))
⇒ #<process ws-server <127.0.0.1:34921>>
5.4 Customization Variables
===========================
The following variables may be changed to control the behavior of the
web server. Specifically the ‘ws-*-cmd’ variables specify the command
lines used to compress data according to content and or transfer
encoding HTTP headers passed to *note ws-response-header::.
-- Variable: ws-compress-cmd
Command used for the “compress” Content or Transfer coding.
-- Variable: ws-deflate-cmd
Command used for the “deflate” Content or Transfer coding.
-- Variable: ws-gzip-cmd
Command used for the “gzip” Content or Transfer coding.

File: web-server.info, Node: Copying, Next: GNU Free Documentation License, Prev: Function Index, Up: Top
Appendix A GNU GENERAL PUBLIC LICENSE
*************************************
Version 3, 29 June 2007
Copyright © 2007 Free Software Foundation, Inc. <http://fsf.org/>
Everyone is permitted to copy and distribute verbatim copies of this
license document, but changing it is not allowed.
Preamble
========
The GNU General Public License is a free, copyleft license for software
and other kinds of works.
The licenses for most software and other practical works are designed
to take away your freedom to share and change the works. By contrast,
the GNU General Public License is intended to guarantee your freedom to
share and change all versions of a program—to make sure it remains free
software for all its users. We, the Free Software Foundation, use the
GNU General Public License for most of our software; it applies also to
any other work released this way by its authors. You can apply it to
your programs, too.
When we speak of free software, we are referring to freedom, not
price. Our General Public Licenses are designed to make sure that you
have the freedom to distribute copies of free software (and charge for
them if you wish), that you receive source code or can get it if you
want it, that you can change the software or use pieces of it in new
free programs, and that you know you can do these things.
To protect your rights, we need to prevent others from denying you
these rights or asking you to surrender the rights. Therefore, you have
certain responsibilities if you distribute copies of the software, or if
you modify it: responsibilities to respect the freedom of others.
For example, if you distribute copies of such a program, whether
gratis or for a fee, you must pass on to the recipients the same
freedoms that you received. You must make sure that they, too, receive
or can get the source code. And you must show them these terms so they
know their rights.
Developers that use the GNU GPL protect your rights with two steps:
(1) assert copyright on the software, and (2) offer you this License
giving you legal permission to copy, distribute and/or modify it.
For the developers’ and authors’ protection, the GPL clearly explains
that there is no warranty for this free software. For both users’ and
authors’ sake, the GPL requires that modified versions be marked as
changed, so that their problems will not be attributed erroneously to
authors of previous versions.
Some devices are designed to deny users access to install or run
modified versions of the software inside them, although the manufacturer
can do so. This is fundamentally incompatible with the aim of
protecting users’ freedom to change the software. The systematic
pattern of such abuse occurs in the area of products for individuals to
use, which is precisely where it is most unacceptable. Therefore, we
have designed this version of the GPL to prohibit the practice for those
products. If such problems arise substantially in other domains, we
stand ready to extend this provision to those domains in future versions
of the GPL, as needed to protect the freedom of users.
Finally, every program is threatened constantly by software patents.
States should not allow patents to restrict development and use of
software on general-purpose computers, but in those that do, we wish to
avoid the special danger that patents applied to a free program could
make it effectively proprietary. To prevent this, the GPL assures that
patents cannot be used to render the program non-free.
The precise terms and conditions for copying, distribution and
modification follow.
TERMS AND CONDITIONS
====================
0. Definitions.
“This License” refers to version 3 of the GNU General Public
License.
“Copyright” also means copyright-like laws that apply to other
kinds of works, such as semiconductor masks.
“The Program” refers to any copyrightable work licensed under this
License. Each licensee is addressed as “you”. “Licensees” and
“recipients” may be individuals or organizations.
To “modify” a work means to copy from or adapt all or part of the
work in a fashion requiring copyright permission, other than the
making of an exact copy. The resulting work is called a “modified
version” of the earlier work or a work “based on” the earlier work.
A “covered work” means either the unmodified Program or a work
based on the Program.
To “propagate” a work means to do anything with it that, without
permission, would make you directly or secondarily liable for
infringement under applicable copyright law, except executing it on
a computer or modifying a private copy. Propagation includes
copying, distribution (with or without modification), making
available to the public, and in some countries other activities as
well.
To “convey” a work means any kind of propagation that enables other
parties to make or receive copies. Mere interaction with a user
through a computer network, with no transfer of a copy, is not
conveying.
An interactive user interface displays “Appropriate Legal Notices”
to the extent that it includes a convenient and prominently visible
feature that (1) displays an appropriate copyright notice, and (2)
tells the user that there is no warranty for the work (except to
the extent that warranties are provided), that licensees may convey
the work under this License, and how to view a copy of this
License. If the interface presents a list of user commands or
options, such as a menu, a prominent item in the list meets this
criterion.
1. Source Code.
The “source code” for a work means the preferred form of the work
for making modifications to it. “Object code” means any non-source
form of a work.
A “Standard Interface” means an interface that either is an
official standard defined by a recognized standards body, or, in
the case of interfaces specified for a particular programming
language, one that is widely used among developers working in that
language.
The “System Libraries” of an executable work include anything,
other than the work as a whole, that (a) is included in the normal
form of packaging a Major Component, but which is not part of that
Major Component, and (b) serves only to enable use of the work with
that Major Component, or to implement a Standard Interface for
which an implementation is available to the public in source code
form. A “Major Component”, in this context, means a major
essential component (kernel, window system, and so on) of the
specific operating system (if any) on which the executable work
runs, or a compiler used to produce the work, or an object code
interpreter used to run it.
The “Corresponding Source” for a work in object code form means all
the source code needed to generate, install, and (for an executable
work) run the object code and to modify the work, including scripts
to control those activities. However, it does not include the
work’s System Libraries, or general-purpose tools or generally
available free programs which are used unmodified in performing
those activities but which are not part of the work. For example,
Corresponding Source includes interface definition files associated
with source files for the work, and the source code for shared
libraries and dynamically linked subprograms that the work is
specifically designed to require, such as by intimate data
communication or control flow between those subprograms and other
parts of the work.
The Corresponding Source need not include anything that users can
regenerate automatically from other parts of the Corresponding
Source.
The Corresponding Source for a work in source code form is that
same work.
2. Basic Permissions.
All rights granted under this License are granted for the term of
copyright on the Program, and are irrevocable provided the stated
conditions are met. This License explicitly affirms your unlimited
permission to run the unmodified Program. The output from running
a covered work is covered by this License only if the output, given
its content, constitutes a covered work. This License acknowledges
your rights of fair use or other equivalent, as provided by
copyright law.
You may make, run and propagate covered works that you do not
convey, without conditions so long as your license otherwise
remains in force. You may convey covered works to others for the
sole purpose of having them make modifications exclusively for you,
or provide you with facilities for running those works, provided
that you comply with the terms of this License in conveying all
material for which you do not control copyright. Those thus making
or running the covered works for you must do so exclusively on your
behalf, under your direction and control, on terms that prohibit
them from making any copies of your copyrighted material outside
their relationship with you.
Conveying under any other circumstances is permitted solely under
the conditions stated below. Sublicensing is not allowed; section
10 makes it unnecessary.
3. Protecting Users’ Legal Rights From Anti-Circumvention Law.
No covered work shall be deemed part of an effective technological
measure under any applicable law fulfilling obligations under
article 11 of the WIPO copyright treaty adopted on 20 December
1996, or similar laws prohibiting or restricting circumvention of
such measures.
When you convey a covered work, you waive any legal power to forbid
circumvention of technological measures to the extent such
circumvention is effected by exercising rights under this License
with respect to the covered work, and you disclaim any intention to
limit operation or modification of the work as a means of
enforcing, against the work’s users, your or third parties’ legal
rights to forbid circumvention of technological measures.
4. Conveying Verbatim Copies.
You may convey verbatim copies of the Program’s source code as you
receive it, in any medium, provided that you conspicuously and
appropriately publish on each copy an appropriate copyright notice;
keep intact all notices stating that this License and any
non-permissive terms added in accord with section 7 apply to the
code; keep intact all notices of the absence of any warranty; and
give all recipients a copy of this License along with the Program.
You may charge any price or no price for each copy that you convey,
and you may offer support or warranty protection for a fee.
5. Conveying Modified Source Versions.
You may convey a work based on the Program, or the modifications to
produce it from the Program, in the form of source code under the
terms of section 4, provided that you also meet all of these
conditions:
a. The work must carry prominent notices stating that you
modified it, and giving a relevant date.
b. The work must carry prominent notices stating that it is
released under this License and any conditions added under
section 7. This requirement modifies the requirement in
section 4 to “keep intact all notices”.
c. You must license the entire work, as a whole, under this
License to anyone who comes into possession of a copy. This
License will therefore apply, along with any applicable
section 7 additional terms, to the whole of the work, and all
its parts, regardless of how they are packaged. This License
gives no permission to license the work in any other way, but
it does not invalidate such permission if you have separately
received it.
d. If the work has interactive user interfaces, each must display
Appropriate Legal Notices; however, if the Program has
interactive interfaces that do not display Appropriate Legal
Notices, your work need not make them do so.
A compilation of a covered work with other separate and independent
works, which are not by their nature extensions of the covered
work, and which are not combined with it such as to form a larger
program, in or on a volume of a storage or distribution medium, is
called an “aggregate” if the compilation and its resulting
copyright are not used to limit the access or legal rights of the
compilation’s users beyond what the individual works permit.
Inclusion of a covered work in an aggregate does not cause this
License to apply to the other parts of the aggregate.
6. Conveying Non-Source Forms.
You may convey a covered work in object code form under the terms
of sections 4 and 5, provided that you also convey the
machine-readable Corresponding Source under the terms of this
License, in one of these ways:
a. Convey the object code in, or embodied in, a physical product
(including a physical distribution medium), accompanied by the
Corresponding Source fixed on a durable physical medium
customarily used for software interchange.
b. Convey the object code in, or embodied in, a physical product
(including a physical distribution medium), accompanied by a
written offer, valid for at least three years and valid for as
long as you offer spare parts or customer support for that
product model, to give anyone who possesses the object code
either (1) a copy of the Corresponding Source for all the
software in the product that is covered by this License, on a
durable physical medium customarily used for software
interchange, for a price no more than your reasonable cost of
physically performing this conveying of source, or (2) access
to copy the Corresponding Source from a network server at no
charge.
c. Convey individual copies of the object code with a copy of the
written offer to provide the Corresponding Source. This
alternative is allowed only occasionally and noncommercially,
and only if you received the object code with such an offer,
in accord with subsection 6b.
d. Convey the object code by offering access from a designated
place (gratis or for a charge), and offer equivalent access to
the Corresponding Source in the same way through the same
place at no further charge. You need not require recipients
to copy the Corresponding Source along with the object code.
If the place to copy the object code is a network server, the
Corresponding Source may be on a different server (operated by
you or a third party) that supports equivalent copying
facilities, provided you maintain clear directions next to the
object code saying where to find the Corresponding Source.
Regardless of what server hosts the Corresponding Source, you
remain obligated to ensure that it is available for as long as
needed to satisfy these requirements.
e. Convey the object code using peer-to-peer transmission,
provided you inform other peers where the object code and
Corresponding Source of the work are being offered to the
general public at no charge under subsection 6d.
A separable portion of the object code, whose source code is
excluded from the Corresponding Source as a System Library, need
not be included in conveying the object code work.
A “User Product” is either (1) a “consumer product”, which means
any tangible personal property which is normally used for personal,
family, or household purposes, or (2) anything designed or sold for
incorporation into a dwelling. In determining whether a product is
a consumer product, doubtful cases shall be resolved in favor of
coverage. For a particular product received by a particular user,
“normally used” refers to a typical or common use of that class of
product, regardless of the status of the particular user or of the
way in which the particular user actually uses, or expects or is
expected to use, the product. A product is a consumer product
regardless of whether the product has substantial commercial,
industrial or non-consumer uses, unless such uses represent the
only significant mode of use of the product.
“Installation Information” for a User Product means any methods,
procedures, authorization keys, or other information required to
install and execute modified versions of a covered work in that
User Product from a modified version of its Corresponding Source.
The information must suffice to ensure that the continued
functioning of the modified object code is in no case prevented or
interfered with solely because modification has been made.
If you convey an object code work under this section in, or with,
or specifically for use in, a User Product, and the conveying
occurs as part of a transaction in which the right of possession
and use of the User Product is transferred to the recipient in
perpetuity or for a fixed term (regardless of how the transaction
is characterized), the Corresponding Source conveyed under this
section must be accompanied by the Installation Information. But
this requirement does not apply if neither you nor any third party
retains the ability to install modified object code on the User
Product (for example, the work has been installed in ROM).
The requirement to provide Installation Information does not
include a requirement to continue to provide support service,
warranty, or updates for a work that has been modified or installed
by the recipient, or for the User Product in which it has been
modified or installed. Access to a network may be denied when the
modification itself materially and adversely affects the operation
of the network or violates the rules and protocols for
communication across the network.
Corresponding Source conveyed, and Installation Information
provided, in accord with this section must be in a format that is
publicly documented (and with an implementation available to the
public in source code form), and must require no special password
or key for unpacking, reading or copying.
7. Additional Terms.
“Additional permissions” are terms that supplement the terms of
this License by making exceptions from one or more of its
conditions. Additional permissions that are applicable to the
entire Program shall be treated as though they were included in
this License, to the extent that they are valid under applicable
law. If additional permissions apply only to part of the Program,
that part may be used separately under those permissions, but the
entire Program remains governed by this License without regard to
the additional permissions.
When you convey a copy of a covered work, you may at your option
remove any additional permissions from that copy, or from any part
of it. (Additional permissions may be written to require their own
removal in certain cases when you modify the work.) You may place
additional permissions on material, added by you to a covered work,
for which you have or can give appropriate copyright permission.
Notwithstanding any other provision of this License, for material
you add to a covered work, you may (if authorized by the copyright
holders of that material) supplement the terms of this License with
terms:
a. Disclaiming warranty or limiting liability differently from
the terms of sections 15 and 16 of this License; or
b. Requiring preservation of specified reasonable legal notices
or author attributions in that material or in the Appropriate
Legal Notices displayed by works containing it; or
c. Prohibiting misrepresentation of the origin of that material,
or requiring that modified versions of such material be marked
in reasonable ways as different from the original version; or
d. Limiting the use for publicity purposes of names of licensors
or authors of the material; or
e. Declining to grant rights under trademark law for use of some
trade names, trademarks, or service marks; or
f. Requiring indemnification of licensors and authors of that
material by anyone who conveys the material (or modified
versions of it) with contractual assumptions of liability to
the recipient, for any liability that these contractual
assumptions directly impose on those licensors and authors.
All other non-permissive additional terms are considered “further
restrictions” within the meaning of section 10. If the Program as
you received it, or any part of it, contains a notice stating that
it is governed by this License along with a term that is a further
restriction, you may remove that term. If a license document
contains a further restriction but permits relicensing or conveying
under this License, you may add to a covered work material governed
by the terms of that license document, provided that the further
restriction does not survive such relicensing or conveying.
If you add terms to a covered work in accord with this section, you
must place, in the relevant source files, a statement of the
additional terms that apply to those files, or a notice indicating
where to find the applicable terms.
Additional terms, permissive or non-permissive, may be stated in
the form of a separately written license, or stated as exceptions;
the above requirements apply either way.
8. Termination.
You may not propagate or modify a covered work except as expressly
provided under this License. Any attempt otherwise to propagate or
modify it is void, and will automatically terminate your rights
under this License (including any patent licenses granted under the
third paragraph of section 11).
However, if you cease all violation of this License, then your
license from a particular copyright holder is reinstated (a)
provisionally, unless and until the copyright holder explicitly and
finally terminates your license, and (b) permanently, if the
copyright holder fails to notify you of the violation by some
reasonable means prior to 60 days after the cessation.
Moreover, your license from a particular copyright holder is
reinstated permanently if the copyright holder notifies you of the
violation by some reasonable means, this is the first time you have
received notice of violation of this License (for any work) from
that copyright holder, and you cure the violation prior to 30 days
after your receipt of the notice.
Termination of your rights under this section does not terminate
the licenses of parties who have received copies or rights from you
under this License. If your rights have been terminated and not
permanently reinstated, you do not qualify to receive new licenses
for the same material under section 10.
9. Acceptance Not Required for Having Copies.
You are not required to accept this License in order to receive or
run a copy of the Program. Ancillary propagation of a covered work
occurring solely as a consequence of using peer-to-peer
transmission to receive a copy likewise does not require
acceptance. However, nothing other than this License grants you
permission to propagate or modify any covered work. These actions
infringe copyright if you do not accept this License. Therefore,
by modifying or propagating a covered work, you indicate your
acceptance of this License to do so.
10. Automatic Licensing of Downstream Recipients.
Each time you convey a covered work, the recipient automatically
receives a license from the original licensors, to run, modify and
propagate that work, subject to this License. You are not
responsible for enforcing compliance by third parties with this
License.
An “entity transaction” is a transaction transferring control of an
organization, or substantially all assets of one, or subdividing an
organization, or merging organizations. If propagation of a
covered work results from an entity transaction, each party to that
transaction who receives a copy of the work also receives whatever
licenses to the work the party’s predecessor in interest had or
could give under the previous paragraph, plus a right to possession
of the Corresponding Source of the work from the predecessor in
interest, if the predecessor has it or can get it with reasonable
efforts.
You may not impose any further restrictions on the exercise of the
rights granted or affirmed under this License. For example, you
may not impose a license fee, royalty, or other charge for exercise
of rights granted under this License, and you may not initiate
litigation (including a cross-claim or counterclaim in a lawsuit)
alleging that any patent claim is infringed by making, using,
selling, offering for sale, or importing the Program or any portion
of it.
11. Patents.
A “contributor” is a copyright holder who authorizes use under this
License of the Program or a work on which the Program is based.
The work thus licensed is called the contributor’s “contributor
version”.
A contributor’s “essential patent claims” are all patent claims
owned or controlled by the contributor, whether already acquired or
hereafter acquired, that would be infringed by some manner,
permitted by this License, of making, using, or selling its
contributor version, but do not include claims that would be
infringed only as a consequence of further modification of the
contributor version. For purposes of this definition, “control”
includes the right to grant patent sublicenses in a manner
consistent with the requirements of this License.
Each contributor grants you a non-exclusive, worldwide,
royalty-free patent license under the contributor’s essential
patent claims, to make, use, sell, offer for sale, import and
otherwise run, modify and propagate the contents of its contributor
version.
In the following three paragraphs, a “patent license” is any
express agreement or commitment, however denominated, not to
enforce a patent (such as an express permission to practice a
patent or covenant not to sue for patent infringement). To “grant”
such a patent license to a party means to make such an agreement or
commitment not to enforce a patent against the party.
If you convey a covered work, knowingly relying on a patent
license, and the Corresponding Source of the work is not available
for anyone to copy, free of charge and under the terms of this
License, through a publicly available network server or other
readily accessible means, then you must either (1) cause the
Corresponding Source to be so available, or (2) arrange to deprive
yourself of the benefit of the patent license for this particular
work, or (3) arrange, in a manner consistent with the requirements
of this License, to extend the patent license to downstream
recipients. “Knowingly relying” means you have actual knowledge
that, but for the patent license, your conveying the covered work
in a country, or your recipient’s use of the covered work in a
country, would infringe one or more identifiable patents in that
country that you have reason to believe are valid.
If, pursuant to or in connection with a single transaction or
arrangement, you convey, or propagate by procuring conveyance of, a
covered work, and grant a patent license to some of the parties
receiving the covered work authorizing them to use, propagate,
modify or convey a specific copy of the covered work, then the
patent license you grant is automatically extended to all
recipients of the covered work and works based on it.
A patent license is “discriminatory” if it does not include within
the scope of its coverage, prohibits the exercise of, or is
conditioned on the non-exercise of one or more of the rights that
are specifically granted under this License. You may not convey a
covered work if you are a party to an arrangement with a third
party that is in the business of distributing software, under which
you make payment to the third party based on the extent of your
activity of conveying the work, and under which the third party
grants, to any of the parties who would receive the covered work
from you, a discriminatory patent license (a) in connection with
copies of the covered work conveyed by you (or copies made from
those copies), or (b) primarily for and in connection with specific
products or compilations that contain the covered work, unless you
entered into that arrangement, or that patent license was granted,
prior to 28 March 2007.
Nothing in this License shall be construed as excluding or limiting
any implied license or other defenses to infringement that may
otherwise be available to you under applicable patent law.
12. No Surrender of Others’ Freedom.
If conditions are imposed on you (whether by court order, agreement
or otherwise) that contradict the conditions of this License, they
do not excuse you from the conditions of this License. If you
cannot convey a covered work so as to satisfy simultaneously your
obligations under this License and any other pertinent obligations,
then as a consequence you may not convey it at all. For example,
if you agree to terms that obligate you to collect a royalty for
further conveying from those to whom you convey the Program, the
only way you could satisfy both those terms and this License would
be to refrain entirely from conveying the Program.
13. Use with the GNU Affero General Public License.
Notwithstanding any other provision of this License, you have
permission to link or combine any covered work with a work licensed
under version 3 of the GNU Affero General Public License into a
single combined work, and to convey the resulting work. The terms
of this License will continue to apply to the part which is the
covered work, but the special requirements of the GNU Affero
General Public License, section 13, concerning interaction through
a network will apply to the combination as such.
14. Revised Versions of this License.
The Free Software Foundation may publish revised and/or new
versions of the GNU General Public License from time to time. Such
new versions will be similar in spirit to the present version, but
may differ in detail to address new problems or concerns.
Each version is given a distinguishing version number. If the
Program specifies that a certain numbered version of the GNU
General Public License “or any later version” applies to it, you
have the option of following the terms and conditions either of
that numbered version or of any later version published by the Free
Software Foundation. If the Program does not specify a version
number of the GNU General Public License, you may choose any
version ever published by the Free Software Foundation.
If the Program specifies that a proxy can decide which future
versions of the GNU General Public License can be used, that
proxy’s public statement of acceptance of a version permanently
authorizes you to choose that version for the Program.
Later license versions may give you additional or different
permissions. However, no additional obligations are imposed on any
author or copyright holder as a result of your choosing to follow a
later version.
15. Disclaimer of Warranty.
THERE IS NO WARRANTY FOR THE PROGRAM, TO THE EXTENT PERMITTED BY
APPLICABLE LAW. EXCEPT WHEN OTHERWISE STATED IN WRITING THE
COPYRIGHT HOLDERS AND/OR OTHER PARTIES PROVIDE THE PROGRAM “AS IS”
WITHOUT WARRANTY OF ANY KIND, EITHER EXPRESSED OR IMPLIED,
INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. THE ENTIRE
RISK AS TO THE QUALITY AND PERFORMANCE OF THE PROGRAM IS WITH YOU.
SHOULD THE PROGRAM PROVE DEFECTIVE, YOU ASSUME THE COST OF ALL
NECESSARY SERVICING, REPAIR OR CORRECTION.
16. Limitation of Liability.
IN NO EVENT UNLESS REQUIRED BY APPLICABLE LAW OR AGREED TO IN
WRITING WILL ANY COPYRIGHT HOLDER, OR ANY OTHER PARTY WHO MODIFIES
AND/OR CONVEYS THE PROGRAM AS PERMITTED ABOVE, BE LIABLE TO YOU FOR
DAMAGES, INCLUDING ANY GENERAL, SPECIAL, INCIDENTAL OR
CONSEQUENTIAL DAMAGES ARISING OUT OF THE USE OR INABILITY TO USE
THE PROGRAM (INCLUDING BUT NOT LIMITED TO LOSS OF DATA OR DATA
BEING RENDERED INACCURATE OR LOSSES SUSTAINED BY YOU OR THIRD
PARTIES OR A FAILURE OF THE PROGRAM TO OPERATE WITH ANY OTHER
PROGRAMS), EVEN IF SUCH HOLDER OR OTHER PARTY HAS BEEN ADVISED OF
THE POSSIBILITY OF SUCH DAMAGES.
17. Interpretation of Sections 15 and 16.
If the disclaimer of warranty and limitation of liability provided
above cannot be given local legal effect according to their terms,
reviewing courts shall apply local law that most closely
approximates an absolute waiver of all civil liability in
connection with the Program, unless a warranty or assumption of
liability accompanies a copy of the Program in return for a fee.
END OF TERMS AND CONDITIONS
===========================
How to Apply These Terms to Your New Programs
=============================================
If you develop a new program, and you want it to be of the greatest
possible use to the public, the best way to achieve this is to make it
free software which everyone can redistribute and change under these
terms.
To do so, attach the following notices to the program. It is safest
to attach them to the start of each source file to most effectively
state the exclusion of warranty; and each file should have at least the
“copyright” line and a pointer to where the full notice is found.
ONE LINE TO GIVE THE PROGRAM'S NAME AND A BRIEF IDEA OF WHAT IT DOES.
Copyright (C) YEAR NAME OF AUTHOR
This program is free software: you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation, either version 3 of the License, or (at
your option) any later version.
This program is distributed in the hope that it will be useful, but
WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program. If not, see <http://www.gnu.org/licenses/>.
Also add information on how to contact you by electronic and paper
mail.
If the program does terminal interaction, make it output a short
notice like this when it starts in an interactive mode:
PROGRAM Copyright (C) YEAR NAME OF AUTHOR
This program comes with ABSOLUTELY NO WARRANTY; for details type ‘show w’.
This is free software, and you are welcome to redistribute it
under certain conditions; type ‘show c’ for details.
The hypothetical commands ‘show w’ and ‘show c’ should show the
appropriate parts of the General Public License. Of course, your
program’s commands might be different; for a GUI interface, you would
use an “about box”.
You should also get your employer (if you work as a programmer) or
school, if any, to sign a “copyright disclaimer” for the program, if
necessary. For more information on this, and how to apply and follow
the GNU GPL, see <http://www.gnu.org/licenses/>.
The GNU General Public License does not permit incorporating your
program into proprietary programs. If your program is a subroutine
library, you may consider it more useful to permit linking proprietary
applications with the library. If this is what you want to do, use the
GNU Lesser General Public License instead of this License. But first,
please read <http://www.gnu.org/philosophy/why-not-lgpl.html>.

File: web-server.info, Node: GNU Free Documentation License, Next: Index, Prev: Copying, Up: Top
Appendix B GNU Free Documentation License
*****************************************
Version 1.3, 3 November 2008
Copyright © 2000, 2001, 2002, 2007, 2008, 2009 Free Software Foundation, Inc.
<http://fsf.org/>
Everyone is permitted to copy and distribute verbatim copies
of this license document, but changing it is not allowed.
0. PREAMBLE
The purpose of this License is to make a manual, textbook, or other
functional and useful document “free” in the sense of freedom: to
assure everyone the effective freedom to copy and redistribute it,
with or without modifying it, either commercially or
noncommercially. Secondarily, this License preserves for the
author and publisher a way to get credit for their work, while not
being considered responsible for modifications made by others.
This License is a kind of “copyleft”, which means that derivative
works of the document must themselves be free in the same sense.
It complements the GNU General Public License, which is a copyleft
license designed for free software.
We have designed this License in order to use it for manuals for
free software, because free software needs free documentation: a
free program should come with manuals providing the same freedoms
that the software does. But this License is not limited to
software manuals; it can be used for any textual work, regardless
of subject matter or whether it is published as a printed book. We
recommend this License principally for works whose purpose is
instruction or reference.
1. APPLICABILITY AND DEFINITIONS
This License applies to any manual or other work, in any medium,
that contains a notice placed by the copyright holder saying it can
be distributed under the terms of this License. Such a notice
grants a world-wide, royalty-free license, unlimited in duration,
to use that work under the conditions stated herein. The
“Document”, below, refers to any such manual or work. Any member
of the public is a licensee, and is addressed as “you”. You accept
the license if you copy, modify or distribute the work in a way
requiring permission under copyright law.
A “Modified Version” of the Document means any work containing the
Document or a portion of it, either copied verbatim, or with
modifications and/or translated into another language.
A “Secondary Section” is a named appendix or a front-matter section
of the Document that deals exclusively with the relationship of the
publishers or authors of the Document to the Document’s overall
subject (or to related matters) and contains nothing that could
fall directly within that overall subject. (Thus, if the Document
is in part a textbook of mathematics, a Secondary Section may not
explain any mathematics.) The relationship could be a matter of
historical connection with the subject or with related matters, or
of legal, commercial, philosophical, ethical or political position
regarding them.
The “Invariant Sections” are certain Secondary Sections whose
titles are designated, as being those of Invariant Sections, in the
notice that says that the Document is released under this License.
If a section does not fit the above definition of Secondary then it
is not allowed to be designated as Invariant. The Document may
contain zero Invariant Sections. If the Document does not identify
any Invariant Sections then there are none.
The “Cover Texts” are certain short passages of text that are
listed, as Front-Cover Texts or Back-Cover Texts, in the notice
that says that the Document is released under this License. A
Front-Cover Text may be at most 5 words, and a Back-Cover Text may
be at most 25 words.
A “Transparent” copy of the Document means a machine-readable copy,
represented in a format whose specification is available to the
general public, that is suitable for revising the document
straightforwardly with generic text editors or (for images composed
of pixels) generic paint programs or (for drawings) some widely
available drawing editor, and that is suitable for input to text
formatters or for automatic translation to a variety of formats
suitable for input to text formatters. A copy made in an otherwise
Transparent file format whose markup, or absence of markup, has
been arranged to thwart or discourage subsequent modification by
readers is not Transparent. An image format is not Transparent if
used for any substantial amount of text. A copy that is not
“Transparent” is called “Opaque”.
Examples of suitable formats for Transparent copies include plain
ASCII without markup, Texinfo input format, LaTeX input format,
SGML or XML using a publicly available DTD, and standard-conforming
simple HTML, PostScript or PDF designed for human modification.
Examples of transparent image formats include PNG, XCF and JPG.
Opaque formats include proprietary formats that can be read and
edited only by proprietary word processors, SGML or XML for which
the DTD and/or processing tools are not generally available, and
the machine-generated HTML, PostScript or PDF produced by some word
processors for output purposes only.
The “Title Page” means, for a printed book, the title page itself,
plus such following pages as are needed to hold, legibly, the
material this License requires to appear in the title page. For
works in formats which do not have any title page as such, “Title
Page” means the text near the most prominent appearance of the
work’s title, preceding the beginning of the body of the text.
The “publisher” means any person or entity that distributes copies
of the Document to the public.
A section “Entitled XYZ” means a named subunit of the Document
whose title either is precisely XYZ or contains XYZ in parentheses
following text that translates XYZ in another language. (Here XYZ
stands for a specific section name mentioned below, such as
“Acknowledgements”, “Dedications”, “Endorsements”, or “History”.)
To “Preserve the Title” of such a section when you modify the
Document means that it remains a section “Entitled XYZ” according
to this definition.
The Document may include Warranty Disclaimers next to the notice
which states that this License applies to the Document. These
Warranty Disclaimers are considered to be included by reference in
this License, but only as regards disclaiming warranties: any other
implication that these Warranty Disclaimers may have is void and
has no effect on the meaning of this License.
2. VERBATIM COPYING
You may copy and distribute the Document in any medium, either
commercially or noncommercially, provided that this License, the
copyright notices, and the license notice saying this License
applies to the Document are reproduced in all copies, and that you
add no other conditions whatsoever to those of this License. You
may not use technical measures to obstruct or control the reading
or further copying of the copies you make or distribute. However,
you may accept compensation in exchange for copies. If you
distribute a large enough number of copies you must also follow the
conditions in section 3.
You may also lend copies, under the same conditions stated above,
and you may publicly display copies.
3. COPYING IN QUANTITY
If you publish printed copies (or copies in media that commonly
have printed covers) of the Document, numbering more than 100, and
the Document’s license notice requires Cover Texts, you must
enclose the copies in covers that carry, clearly and legibly, all
these Cover Texts: Front-Cover Texts on the front cover, and
Back-Cover Texts on the back cover. Both covers must also clearly
and legibly identify you as the publisher of these copies. The
front cover must present the full title with all words of the title
equally prominent and visible. You may add other material on the
covers in addition. Copying with changes limited to the covers, as
long as they preserve the title of the Document and satisfy these
conditions, can be treated as verbatim copying in other respects.
If the required texts for either cover are too voluminous to fit
legibly, you should put the first ones listed (as many as fit
reasonably) on the actual cover, and continue the rest onto
adjacent pages.
If you publish or distribute Opaque copies of the Document
numbering more than 100, you must either include a machine-readable
Transparent copy along with each Opaque copy, or state in or with
each Opaque copy a computer-network location from which the general
network-using public has access to download using public-standard
network protocols a complete Transparent copy of the Document, free
of added material. If you use the latter option, you must take
reasonably prudent steps, when you begin distribution of Opaque
copies in quantity, to ensure that this Transparent copy will
remain thus accessible at the stated location until at least one
year after the last time you distribute an Opaque copy (directly or
through your agents or retailers) of that edition to the public.
It is requested, but not required, that you contact the authors of
the Document well before redistributing any large number of copies,
to give them a chance to provide you with an updated version of the
Document.
4. MODIFICATIONS
You may copy and distribute a Modified Version of the Document
under the conditions of sections 2 and 3 above, provided that you
release the Modified Version under precisely this License, with the
Modified Version filling the role of the Document, thus licensing
distribution and modification of the Modified Version to whoever
possesses a copy of it. In addition, you must do these things in
the Modified Version:
A. Use in the Title Page (and on the covers, if any) a title
distinct from that of the Document, and from those of previous
versions (which should, if there were any, be listed in the
History section of the Document). You may use the same title
as a previous version if the original publisher of that
version gives permission.
B. List on the Title Page, as authors, one or more persons or
entities responsible for authorship of the modifications in
the Modified Version, together with at least five of the
principal authors of the Document (all of its principal
authors, if it has fewer than five), unless they release you
from this requirement.
C. State on the Title page the name of the publisher of the
Modified Version, as the publisher.
D. Preserve all the copyright notices of the Document.
E. Add an appropriate copyright notice for your modifications
adjacent to the other copyright notices.
F. Include, immediately after the copyright notices, a license
notice giving the public permission to use the Modified
Version under the terms of this License, in the form shown in
the Addendum below.
G. Preserve in that license notice the full lists of Invariant
Sections and required Cover Texts given in the Document’s
license notice.
H. Include an unaltered copy of this License.
I. Preserve the section Entitled “History”, Preserve its Title,
and add to it an item stating at least the title, year, new
authors, and publisher of the Modified Version as given on the
Title Page. If there is no section Entitled “History” in the
Document, create one stating the title, year, authors, and
publisher of the Document as given on its Title Page, then add
an item describing the Modified Version as stated in the
previous sentence.
J. Preserve the network location, if any, given in the Document
for public access to a Transparent copy of the Document, and
likewise the network locations given in the Document for
previous versions it was based on. These may be placed in the
“History” section. You may omit a network location for a work
that was published at least four years before the Document
itself, or if the original publisher of the version it refers
to gives permission.
K. For any section Entitled “Acknowledgements” or “Dedications”,
Preserve the Title of the section, and preserve in the section
all the substance and tone of each of the contributor
acknowledgements and/or dedications given therein.
L. Preserve all the Invariant Sections of the Document, unaltered
in their text and in their titles. Section numbers or the
equivalent are not considered part of the section titles.
M. Delete any section Entitled “Endorsements”. Such a section
may not be included in the Modified Version.
N. Do not retitle any existing section to be Entitled
“Endorsements” or to conflict in title with any Invariant
Section.
O. Preserve any Warranty Disclaimers.
If the Modified Version includes new front-matter sections or
appendices that qualify as Secondary Sections and contain no
material copied from the Document, you may at your option designate
some or all of these sections as invariant. To do this, add their
titles to the list of Invariant Sections in the Modified Version’s
license notice. These titles must be distinct from any other
section titles.
You may add a section Entitled “Endorsements”, provided it contains
nothing but endorsements of your Modified Version by various
parties—for example, statements of peer review or that the text has
been approved by an organization as the authoritative definition of
a standard.
You may add a passage of up to five words as a Front-Cover Text,
and a passage of up to 25 words as a Back-Cover Text, to the end of
the list of Cover Texts in the Modified Version. Only one passage
of Front-Cover Text and one of Back-Cover Text may be added by (or
through arrangements made by) any one entity. If the Document
already includes a cover text for the same cover, previously added
by you or by arrangement made by the same entity you are acting on
behalf of, you may not add another; but you may replace the old
one, on explicit permission from the previous publisher that added
the old one.
The author(s) and publisher(s) of the Document do not by this
License give permission to use their names for publicity for or to
assert or imply endorsement of any Modified Version.
5. COMBINING DOCUMENTS
You may combine the Document with other documents released under
this License, under the terms defined in section 4 above for
modified versions, provided that you include in the combination all
of the Invariant Sections of all of the original documents,
unmodified, and list them all as Invariant Sections of your
combined work in its license notice, and that you preserve all
their Warranty Disclaimers.
The combined work need only contain one copy of this License, and
multiple identical Invariant Sections may be replaced with a single
copy. If there are multiple Invariant Sections with the same name
but different contents, make the title of each such section unique
by adding at the end of it, in parentheses, the name of the
original author or publisher of that section if known, or else a
unique number. Make the same adjustment to the section titles in
the list of Invariant Sections in the license notice of the
combined work.
In the combination, you must combine any sections Entitled
“History” in the various original documents, forming one section
Entitled “History”; likewise combine any sections Entitled
“Acknowledgements”, and any sections Entitled “Dedications”. You
must delete all sections Entitled “Endorsements.”
6. COLLECTIONS OF DOCUMENTS
You may make a collection consisting of the Document and other
documents released under this License, and replace the individual
copies of this License in the various documents with a single copy
that is included in the collection, provided that you follow the
rules of this License for verbatim copying of each of the documents
in all other respects.
You may extract a single document from such a collection, and
distribute it individually under this License, provided you insert
a copy of this License into the extracted document, and follow this
License in all other respects regarding verbatim copying of that
document.
7. AGGREGATION WITH INDEPENDENT WORKS
A compilation of the Document or its derivatives with other
separate and independent documents or works, in or on a volume of a
storage or distribution medium, is called an “aggregate” if the
copyright resulting from the compilation is not used to limit the
legal rights of the compilation’s users beyond what the individual
works permit. When the Document is included in an aggregate, this
License does not apply to the other works in the aggregate which
are not themselves derivative works of the Document.
If the Cover Text requirement of section 3 is applicable to these
copies of the Document, then if the Document is less than one half
of the entire aggregate, the Document’s Cover Texts may be placed
on covers that bracket the Document within the aggregate, or the
electronic equivalent of covers if the Document is in electronic
form. Otherwise they must appear on printed covers that bracket
the whole aggregate.
8. TRANSLATION
Translation is considered a kind of modification, so you may
distribute translations of the Document under the terms of section
4. Replacing Invariant Sections with translations requires special
permission from their copyright holders, but you may include
translations of some or all Invariant Sections in addition to the
original versions of these Invariant Sections. You may include a
translation of this License, and all the license notices in the
Document, and any Warranty Disclaimers, provided that you also
include the original English version of this License and the
original versions of those notices and disclaimers. In case of a
disagreement between the translation and the original version of
this License or a notice or disclaimer, the original version will
prevail.
If a section in the Document is Entitled “Acknowledgements”,
“Dedications”, or “History”, the requirement (section 4) to
Preserve its Title (section 1) will typically require changing the
actual title.
9. TERMINATION
You may not copy, modify, sublicense, or distribute the Document
except as expressly provided under this License. Any attempt
otherwise to copy, modify, sublicense, or distribute it is void,
and will automatically terminate your rights under this License.
However, if you cease all violation of this License, then your
license from a particular copyright holder is reinstated (a)
provisionally, unless and until the copyright holder explicitly and
finally terminates your license, and (b) permanently, if the
copyright holder fails to notify you of the violation by some
reasonable means prior to 60 days after the cessation.
Moreover, your license from a particular copyright holder is
reinstated permanently if the copyright holder notifies you of the
violation by some reasonable means, this is the first time you have
received notice of violation of this License (for any work) from
that copyright holder, and you cure the violation prior to 30 days
after your receipt of the notice.
Termination of your rights under this section does not terminate
the licenses of parties who have received copies or rights from you
under this License. If your rights have been terminated and not
permanently reinstated, receipt of a copy of some or all of the
same material does not give you any rights to use it.
10. FUTURE REVISIONS OF THIS LICENSE
The Free Software Foundation may publish new, revised versions of
the GNU Free Documentation License from time to time. Such new
versions will be similar in spirit to the present version, but may
differ in detail to address new problems or concerns. See
<http://www.gnu.org/copyleft/>.
Each version of the License is given a distinguishing version
number. If the Document specifies that a particular numbered
version of this License “or any later version” applies to it, you
have the option of following the terms and conditions either of
that specified version or of any later version that has been
published (not as a draft) by the Free Software Foundation. If the
Document does not specify a version number of this License, you may
choose any version ever published (not as a draft) by the Free
Software Foundation. If the Document specifies that a proxy can
decide which future versions of this License can be used, that
proxy’s public statement of acceptance of a version permanently
authorizes you to choose that version for the Document.
11. RELICENSING
“Massive Multiauthor Collaboration Site” (or “MMC Site”) means any
World Wide Web server that publishes copyrightable works and also
provides prominent facilities for anybody to edit those works. A
public wiki that anybody can edit is an example of such a server.
A “Massive Multiauthor Collaboration” (or “MMC”) contained in the
site means any set of copyrightable works thus published on the MMC
site.
“CC-BY-SA” means the Creative Commons Attribution-Share Alike 3.0
license published by Creative Commons Corporation, a not-for-profit
corporation with a principal place of business in San Francisco,
California, as well as future copyleft versions of that license
published by that same organization.
“Incorporate” means to publish or republish a Document, in whole or
in part, as part of another Document.
An MMC is “eligible for relicensing” if it is licensed under this
License, and if all works that were first published under this
License somewhere other than this MMC, and subsequently
incorporated in whole or in part into the MMC, (1) had no cover
texts or invariant sections, and (2) were thus incorporated prior
to November 1, 2008.
The operator of an MMC Site may republish an MMC contained in the
site under CC-BY-SA on the same site at any time before August 1,
2009, provided the MMC is eligible for relicensing.
ADDENDUM: How to use this License for your documents
====================================================
To use this License in a document you have written, include a copy of
the License in the document and put the following copyright and license
notices just after the title page:
Copyright (C) YEAR YOUR NAME.
Permission is granted to copy, distribute and/or modify this document
under the terms of the GNU Free Documentation License, Version 1.3
or any later version published by the Free Software Foundation;
with no Invariant Sections, no Front-Cover Texts, and no Back-Cover
Texts. A copy of the license is included in the section entitled ``GNU
Free Documentation License''.
If you have Invariant Sections, Front-Cover Texts and Back-Cover
Texts, replace the “with...Texts.” line with this:
with the Invariant Sections being LIST THEIR TITLES, with
the Front-Cover Texts being LIST, and with the Back-Cover Texts
being LIST.
If you have Invariant Sections without Cover Texts, or some other
combination of the three, merge those two alternatives to suit the
situation.
If your document contains nontrivial examples of program code, we
recommend releasing these examples in parallel under your choice of free
software license, such as the GNU General Public License, to permit
their use in free software.

File: web-server.info, Node: Index, Prev: GNU Free Documentation License, Up: Top
Index
*****
[index]
* Menu:
* content type: Function Index. (line 60)
* function index: Function Index. (line 6)
* handler function: Handlers. (line 41)
* handlers: Handlers. (line 6)
* introduction: Introduction. (line 6)
* matchers: Handlers. (line 17)
* requests: Requests. (line 6)
* start and stop: Function Index. (line 32)
* usage examples: Usage Examples. (line 6)
* ws-compress-cmd: Function Index. (line 165)
* ws-deflate-cmd: Function Index. (line 168)
* ws-gzip-cmd: Function Index. (line 171)
* ws-in-directory-p: Function Index. (line 113)
* ws-request: Function Index. (line 19)
* ws-response-header: Function Index. (line 60)
* ws-send: Function Index. (line 87)
* ws-send-404: Function Index. (line 95)
* ws-send-500: Function Index. (line 91)
* ws-send-directory-list: Function Index. (line 106)
* ws-send-file: Function Index. (line 99)
* ws-server: Function Index. (line 13)
* ws-servers: Function Index. (line 41)
* ws-start: Function Index. (line 35)
* ws-stop: Function Index. (line 44)
* ws-stop-all: Function Index. (line 50)
* ws-web-socket-connect: Function Index. (line 145)
* ws-with-authentication: Function Index. (line 125)

Tag Table:
Node: Top709
Node: Introduction2088
Node: Handlers2778
Node: Requests4796
Node: Usage Examples6114
Node: Hello World7048
Node: Hello World UTF87885
Node: Hello World HTML9065
Node: File Server9780
Node: URL Parameter Echo11143
Node: POST Echo12377
Node: Basic Authentication13446
Node: Org-mode Export14987
Node: File Upload17729
Node: Web Socket18885
Node: Gzipped Transfer Encoding22129
Node: Chunked Transfer Encoding23797
Node: Function Index25592
Ref: ws-server25876
Ref: ws-request26202
Ref: ws-start26966
Ref: ws-servers27253
Ref: ws-stop27346
Ref: ws-stop-all27579
Ref: ws-response-header27872
Ref: ws-send29112
Ref: ws-send-50029291
Ref: ws-send-40429448
Ref: ws-send-file29598
Ref: ws-send-directory-list29971
Ref: ws-in-directory-p30353
Ref: ws-with-authentication30672
Ref: ws-web-socket-connect31508
Ref: ws-compress-cmd32395
Ref: ws-deflate-cmd32495
Ref: ws-gzip-cmd32593
Node: Copying32685
Node: GNU Free Documentation License70476
Node: Index95831

End Tag Table

Local Variables:
coding: utf-8
End:
Copy permalink