Updated the HTTP manual. Finaly done.

This commit is contained in:
Diego Nehab 2004-06-16 23:21:49 +00:00
parent 9fc682a106
commit 27c8ae30aa
3 changed files with 71 additions and 95 deletions

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@ -48,11 +48,9 @@ implementation conforms to the HTTP/1.1 standard,
<p>
The module exports functions that provide HTTP functionality in different
levels of abstraction, from the simple
<a href="#get"><tt>get</tt></a> function, through the generic
<a href="http://lua-users.org/wiki/FiltersSourcesAndSinks">LTN12</a> based
<a href="#request"><tt>request</tt></a> function, down to
even lower-level if you bother to look through the source code.
levels of abstraction. From the simple
string oriented requests, through generic
<a href="http://lua-users.org/wiki/FiltersSourcesAndSinks">LTN12</a> based, down to even lower-level if you bother to look through the source code.
</p>
<p>
@ -118,72 +116,10 @@ the HTTP module:
<li> <tt>USERAGENT</tt>: default user agent reported to server.
</ul>
<!-- http.get +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ -->
<p class=name id=get>
http.<b>get(</b>url<b>)</b><br>
</p>
<p class=description>
Performs the HTTP method <tt>GET</tt>.
</p>
<p class=parameters>
<tt>Url</tt> identifies the entity to retrieve.
</p>
<p class=return>
If successful, the function returns the response message body, the mime
headers, and the status code. In case of failure, the
function returns <tt><b>nil</b></tt> followed by an error message.
</p>
<p class=note>
Note: The function is trivially implemented with the use of the
<a href="#request"><tt>request</tt></a> function.
</p>
<pre class=example>
-- load the http module
http = require("http")
-- connect to server "www.tecgraf.puc-rio.br" and retrieves this manual
-- file from "/luasocket/http.html"
b, h, c = http.get("http://www.tecgraf.puc-rio.br/luasocket/http.html")
-- connect to server "www.tecgraf.puc-rio.br" and tries to retrieve
-- "~diego/auth/index.html". Fails because authentication is needed.
b, h, c = http.get("http://www.tecgraf.puc-rio.br/~diego/auth/index.html")
-- b returns some useless page telling about the denied access,
-- h returns authentication information
-- and c returns with value 401 (Authentication Required)
-- tries to connect to server "wrong.host" to retrieve "/"
-- and fails because the host does not exist.
r, e = http.get("http://wrong.host/")
-- r is nil, and e returns with value "host not found"
</pre>
<!-- http.post ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ -->
<p class=name id=post>
http.<b>post(</b>url, body<b>)</b><br>
</p>
<p class=description>
Same as <a href="#get"><tt>get</tt></a>, except
that the <tt>POST</tt> method is used and the request
message <tt>body</tt> is sent along with the request.
</p>
<p class=note>
Note: This function is also trivially implemented with the use of the
<a href="#request"><tt>request</tt></a> function.
</p>
<!-- http.request ++++++++++++++++++++++++++++++++++++++++++++++++++++++ -->
<p class=name id=request>
http.<b>request(</b>url [, body]<b>)</b><br>
http.<b>request{</b><br>
&nbsp;&nbsp;url = <i>string</i>,<br>
&nbsp;&nbsp;[sink = <i>LTN12 sink</i>,]<br>
@ -197,11 +133,23 @@ http.<b>request{</b><br>
</p>
<p class=description>
Performs the generic HTTP request, controlled by a request table.
The request function has two forms. The simple form downloads
a URL using the <tt>GET</tt> or <tt>POST</tt> method and is based
on strings. The generic form performs any HTTP method and is
<a href=http://lua-users.org/wiki/FiltersSourcesAndSinks>LTN12</a> based.
</p>
<p class=parameters>
The most important parameters are the <tt>url</tt> and the <em>simple</em>
If the first argument of the <tt>request</tt> function is a string, it
should be an <tt>url</tt>. In that case, if a <tt>body</tt>
is provided as a string, the function will perform a <tt>POST</tt> method
in the <tt>url</tt>. Otherwise, it performs a <tt>GET</tt> in the
<tt>url</tt>
</p>
<p class=parameters>
If the first argument is instead a table, the most important fields are
the <tt>url</tt> and the <em>simple</em>
<a href="http://lua-users.org/wiki/FiltersSourcesAndSinks">LTN12</a>
<tt>sink</tt> that will receive the downloaded content.
Any part of the <tt>url</tt> can be overridden by including
@ -232,20 +180,15 @@ function from automatically following 301 or 302 server redirect messages.
<p class=return>
In case of failure, the function returns <tt><b>nil</b></tt> followed by an
error message. If successful, the function returns a table
with all components of the response message. The response table has the following form:
error message. If successful, the simple form returns the response
body as a string, followed by the response status code, the response
headers and the response status line. The complex function returns the same
information, except the first return value is just the number 1 (the body
goes to the <tt>sink</tt>).
</p>
<blockquote><tt>
respt = {<br>
&nbsp;&nbsp;headers = <i>header-table</i>,<br>
&nbsp;&nbsp;status = <i>string</i>,<br>
&nbsp;&nbsp;code = <i>number</i>,<br>
}
</tt></blockquote>
<p class=return>
Even when the server fails to provide the contents of the requested URL (URL not found, for example), the
Even when the server fails to provide the contents of the requested URL (URL not found, for example),
it usually returns a message body (a web page informing the
URL was not found or some other useless page). To make sure the
operation was successful, check the returned status <tt>code</tt>. For
@ -254,6 +197,35 @@ href="http://www.cs.princeton.edu/~diego/rfc/rfc2616.txt">RFC
2616</a>.
</p>
<p class=description>
Here are a few examples with the simple interface:
</p>
<pre class=example>
-- load the http module
http = require("http")
-- connect to server "www.tecgraf.puc-rio.br" and retrieves this manual
-- file from "/luasocket/http.html"
b = http.request("http://www.tecgraf.puc-rio.br/luasocket/http.html")
-- connect to server "www.tecgraf.puc-rio.br" and tries to retrieve
-- "~diego/auth/index.html". Fails because authentication is needed.
b, c, h = http.request("http://www.tecgraf.puc-rio.br/~diego/auth/index.html")
-- b returns some useless page telling about the denied access,
-- h returns authentication information
-- and c returns with value 401 (Authentication Required)
-- tries to connect to server "wrong.host" to retrieve "/"
-- and fails because the host does not exist.
r, e = http.request("http://wrong.host/")
-- r is nil, and e returns with value "host not found"
</pre>
<p class=description>
And here is an example using the generic interface:
</p>
<pre class=example>
-- load the http module
http = require("http")
@ -261,12 +233,12 @@ http = require("http")
-- Requests information about a document, without downloading it.
-- Useful, for example, if you want to display a download gauge and need
-- to know the size of the document in advance
respt = http.request {
r, c, h = http.request {
method = "HEAD",
url = "http://www.tecgraf.puc-rio.br/~diego"
}
-- Would return the following headers:
-- respt.headers = {
-- r is 1, c is 200, and h would return the following headers:
-- h = {
-- date = "Tue, 18 Sep 2001 20:42:21 GMT",
-- server = "Apache/1.3.12 (Unix) (Red Hat/Linux)",
-- ["last-modified"] = "Wed, 05 Sep 2001 06:11:20 GMT",
@ -307,15 +279,11 @@ mime = require("mime")
-- Connect to server "www.tecgraf.puc-rio.br" and tries to retrieve
-- "~diego/auth/index.html", using the provided name and password to
-- authenticate the request
respt = http.request{
url = "http://www.tecgraf.puc-rio.br/~diego/auth/index.html",
user = "diego",
password = "password"
}
b, c, h = http.request("http://diego:password@www.tecgraf.puc-rio.br/~diego/auth/index.html")
-- Alternatively, one could fill the appropriate header and authenticate
-- the request directly.
respt = http.request {
r, c = http.request {
url = "http://www.tecgraf.puc-rio.br/~diego/auth/index.html",
headers = { authentication = "Basic " .. (mime.b64("diego:password")) }
}

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@ -50,7 +50,7 @@
<a href="ftp.html">FTP</a>
<blockquote>
<a href="ftp.html#get">get</a>,
<a href="ftp.html#put">put</a>
<a href="ftp.html#put">put</a>.
</blockquote>
</blockquote>
@ -59,8 +59,6 @@
<blockquote>
<a href="http.html">HTTP</a>
<blockquote>
<a href="http.html#get">get</a>,
<a href="http.html#post">post</a>,
<a href="http.html#request">request</a>.
</blockquote>
</blockquote>

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@ -36,13 +36,22 @@
<h2 id=url>URL</h2>
<p>
The module <tt>url.lua</tt> provides functions to parse, protect,
The <tt>url</tt> namespace provides functions to parse, protect,
and build URLs, as well as functions to compose absolute URLs
from base and relative URLs, according to
<a href="http://www.cs.princeton.edu/~diego/rfc/rfc2396.txt">RFC
2396</a>.
</p>
<p>
To obtain the <tt>url</tt> namespace, run:
</p>
<pre class=example>
-- loads the URL module
local url = require("url")
</pre>
<p>
An URL is defined by the following grammar:
</p>
@ -67,7 +76,8 @@ Builds an absolute URL from a base URL and a relative URL.
</p>
<p class=parameters>
<tt>Base</tt> is a string with the base URL and <tt>relative</tt> is a
<tt>Base</tt> is a string with the base URL or
a parsed URL table. <tt>Relative</tt> is a
string with the relative URL.
</p>