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→Command Line
BaseX offers a RESTful API for accessing database resources via URLs.
REST ([httphttps://en.wikipedia.org/wiki/Representational_State_Transfer REpresentational State Transfer])
facilitates a simple and fast access to databases through HTTP. The HTTP methods
GET, PUT, DELETE, and POST can be used to interact with the database.
The root URL lists all available databases. The following examples assume that
you have created a database instance from the [httphttps://files.basex.org/xml/factbook.xml factbook.xml] document:
:<code>http://localhost:8984/rest</code>
<pre classsyntaxhighlight lang="brush:xml">
<rest:databases resources="1" xmlns:rest="http://basex.org/rest">
<rest:database resources="1" size="1813599">factbook</rest:database>
</rest:databases>
</presyntaxhighlight>
The resources of a database can be listed by specifying the database, and potential sub directories, in the URL.
:<code>http://localhost:8984/rest/factbook</code>
<pre classsyntaxhighlight lang="brush:xml">
<rest:database name="factbook" resources="1" xmlns:rest="http://basex.org/rest">
<rest:resource type="xml" content-type="application/xml" size="77192">factbook.xml</rest:resource>
</rest:database>
</presyntaxhighlight>
The contents of a database can be retrieved by directly addressing the resource:
Additionally, the following '''operations''' can be specified:
* {{Code|query}}: Evaluate an XQuery expression. If a database or database path is specified in the URL, it is used set as initial query context.
* {{Code|command}}: Execute a single [[Commands|database command]].
* {{Code|run}}: Evaluate an XQuery file or command script located on the server. The file path is resolved against the directory specified by <code>[[Options#WEBPATH{{Option|RESTPATH]]</code> }} (before, it was resolved against <code>[[Options#WEBPATH{{Option|WEBPATH]]</code>}}). Similar to {{Code|query}}, a database or database path is set as context.
; Examples
* Lists all resources found in the '''tmp''' path of the ''factbook'' database:<br/><code>http://localhost:8984/rest/factbook/tmp</code>
* Returns the number of documents in a database:<br/><code>http://localhost:8984/rest/database?query=count(.)</code>
* Serializes a document as JSONML:<br/><code>http://localhost:8984/rest/factbook/factbook.xml?method=json&json=format=jsonml</code>
* Create an empty database and return database information:
<pre classsyntaxhighlight lang="brush:xml">
<commands>
<create-db name='db'/>
<info-db/>
</commands>
</presyntaxhighlight>
For the other commands, the following child elements are supported:
* Return the first five city names of the <b>factbook</b> database:
<pre classsyntaxhighlight lang="brush:xml">
<rest:query xmlns:rest="http://basex.org/rest">
<rest:text><![CDATA[ (//city/name)[position() <= 5] ]]></rest:text>
</rest:query>
</presyntaxhighlight>
* Return string lengths of all text nodes that are found in the node that has been specified as initial context node:
<pre classsyntaxhighlight lang="brush:xml">
<query>
<text>for $i in .//text() return string-length($i)</text>
</context>
</query>
</presyntaxhighlight>
* Return the registered database users encoded in <code>ISO-8859-1</code>:
<pre classsyntaxhighlight lang="brush:xml">
<command>
<text>show users</text>
<parameter name='encoding' value='ISO-8859-1'/>
</command>
</presyntaxhighlight>
* Create a new database from the specified input and preserve all whitespaces:
<pre classsyntaxhighlight lang="brush:xml">
<command>
<text>create db test http://files.basex.org/xml/xmark.xml</text>
<option name='chop' value='false'/>
</command>
</presyntaxhighlight>
* Bind value to the {{Code|$person}} variable and run query <code>find-person.xq</code>, which must be located in the directory specified by <code>[[Options#WEBPATH{{Option|WEBPATH]]</code>}}:<pre classsyntaxhighlight lang="brush:xml">
<run>
<variable name='person' value='Johannes Müller'/>
<text>find-person.xq</text>
</run>
</presyntaxhighlight>
==PUT Method==
* The following request assigns two variables to a server-side query file <code>mult.xq</code> placed in the HTTP directory:<br/><code>http://localhost:8984/rest?run=mult.xq&$a=21&$b=2</code>
<pre classsyntaxhighlight lang="brush:xquery">
(: XQuery file: mult.xq :)
declare variable $a as xs:integer external;
declare variable $b as xs:integer external;
<mult>{ $a * $b }</mult>
</presyntaxhighlight>
The dollar sign can be omitted as long as the variable name does not equal a parameter keyword (e.g.: <code>method</code>).
If <code>query</code> or <code>run</code> is used as operation, external variables can be specified via the <code><variable/></code> element:
<pre classsyntaxhighlight lang="brush:xml">
<query xmlns="http://basex.org/rest">
<text><![CDATA[
<variable name="b" value="2"/>
</query>
</presyntaxhighlight>
=Response=
<code>org.basex.util.Base64</code> can be used for that purpose:
<pre classsyntaxhighlight lang="brush:java">
import java.net.*;
import org.basex.util.*;
}
}
</presyntaxhighlight>
===Content-Types===
the connection (in this example we explicitly store the input file as raw):
<pre classsyntaxhighlight lang="brush:java">
// store input as raw
conn.setRequestProperty("Content-Type", "application/octet-stream");
</presyntaxhighlight>
See the [[REST#PUT Requests|PUT Requests]] section for a description of the possible content-types.
==Command Line==
Tools such as the Linux commands [httphttps://www.gnu.org/s/wget/ Wget] or [http://curl.haxx.se/ cURL] exist to
perform HTTP requests (try copy & paste):
;Version 8.1
* Added: Support for input-specific content-type parameters
* Updated: The [[#GET Method|run operation]] now resolves file paths against the [[Options#RESTPATH{{Option|RESTPATH]] }} option.
;Version 8.0
