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==Examples==
===Status Only===Simple GET request. As the attribute <code>{{Code|status-only</code> }} is set to true, only the response element is returned.
===Google Homepage=== Retrieve the Google search home pagewith a timeout of 10 seconds. In order to [[http://home.ccil.org/~cowan/XML/tagsoup/ Parsers#HTML_Parser|parse HTML]], TagSoup] must be referenced contained in the class path in order to parse html.
===POST Request===
<query xmlns="http://basex.org/rest"> <text><![CDATA[ <html>{ for $i in 1 to 3 return <div>Section {$i }</div> }</html> ]]></text> </query>
no edit summary
This [[Module Library|XQuery Module]] contains a single function to send HTTP requests and handle HTTP responses. The function <code>{{Code|send-request</code> }} is based on the [http://expath.org/spec/http-client EXPath HTTP Client Module]. It gives full control over the available request and response parameters. For simple GET requests, the [[Fetch Module]] may be sufficient. With {{Version|9.0}}, if <code><http:header name="Accept-Encoding" value="gzip"/></code> is specified and if the addressed web server provides support for the {{Code|gzip}} compression algorithm, the response will automatically be decompressed.
=Conventions=
All functions in this module are assigned to the <code><nowiki>http://expath.org/ns/http-client</nowiki></code> namespace, which is statically bound to the <code>{{Code|http</code> }} prefix.<br/>All errors are assigned to the <code><nowiki>http://expath.org/ns/error</nowiki></code> namespace, which is statically bound to the <code>{{Code|exerr</code> }} prefix.
=Functions=
==http:send-request==
{|width='100%'
|-
| width='90120' | '''Signatures'''|<code><b>{{Func|http:send-request</b>(|$request as element(http:request)?, $href as xs:string?, $bodies as item()*) as |item()+</code>}}<br/><code><b>{{Func|http:send-request</b>(|$request as element(http:request)) as |item()+</code>}}<br /><code><b>{{Func|http:send-request</b>(|$request as element(http:request)?, $href as xs:string?) as |item()+</code>}}<br />
|-
| '''Summary'''
|Sends an HTTP request and interprets the corresponding response. <code>{{Code|$request</code> }} contains the parameters of the HTTP request such as HTTP method and headers. In addition to this it can also contain the URI to which the request will be sent and the body of the HTTP method. If the URI is not given with the parameter <code>{{Code|$href</code>}}, its value in <code>{{Code|$request</code> }} is used instead. <br/>The structure of <code>{{Code|http:request</code> }} element follows the [http://expath.org/spec/http-client EXPath] specification. Both basic and digest authentication is supported.
|-
| '''NotesErrors'''|The attribute {{Error|HC0001|#Errors}} an HTTP error occurred.<codebr/>auth{{Error|HC0002|#Errors}} error parsing the entity content as XML or HTML.<br/>{{Error|HC0003|#Errors}} with a multipart response, the override-methodmedia-type must be either a multipart media type or application/octet-stream.<br/code> of {{Error|HC0004|#Errors}} the src attribute on the body element is mutually exclusive with all other attribute (except the media-type).<codebr/>${{Error|HC0005|#Errors}} the requestelement is not valid.<br/code> is not considered in our implementation because we are handling only basic authentication{{Error|HC0006|#Errors}} a timeout occurred waiting for the response.
|}
'''Query:'''
</http:response></pre>
'''Query:'''
<pre class="brush:xquery">http:send-request(<http:request method='get' href='http://www.google.com' timeout='10'/>)</pre>
'''Result:'''
<pre class="brush:xml">
</body>
</html>
</pre>
The response content type can also be overwritten in order to retrieve HTML pages and other textual data as plain string (using {{Code|text/plain}}) or in its binary representation (using {{Code|application/octet-stream}}). With the {{Code|http:header}} element, a custom user agent can be set. See the following example:
'''Query:'''
<pre class="brush:xquery">
let $binary := http:send-request(
<http:request method='get'
override-media-type='application/octet-stream'
href='http://www.google.com'>
<http:header name="User-Agent" value="Opera"/>
</http:request>
)[2]
return try {
html:parse($binary)
} catch * {
'Conversion to XML failed: ' || $err:description
}
</pre>
===SVG Data===
Content-type ending with +xml, e.g. image/svg+xml.
</svg></pre>
POST request to the BaseX REST Service, specifying a username and password.
method='post' username='admin' password='admin' send-authorization='true'>
<http:body media-type='application/xml'>
</http:body>
</http:request>
</pre>
=Errors= {| class="wikitable" width="100%"! width="110"|Code|Description|-|{{Code|HC0001}}|An HTTP error occurred.|-|{{Code|HC0002}}|Error parsing the entity content as XML or HTML.|-|{{Code|HC0003}}|With a multipart response, the override-media-type must be either a multipart media type or application/octet-stream.|-|{{Code|HC0004}}|The src attribute on the body element is mutually exclusive with all other attribute (except the media-type).|-|{{Code|HC0005}}|The request element is not valid.|-|{{Code|HC0006}}|A timeout occurred waiting for the response.|} =Changelog= ;Version 9.0* Updated: support for gzipped content encoding ;Version 8.0* Added: digest authentication ;Version 7.6* Updated: [[Category#http:send-request|http:XQuerysend-request]]: {{Code|HC0002}} is raised if the input cannot be parsed or converted to the final data type.* Updated: errors are using {{Code|text/plain}} as media-type.
