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The root URL lists all available databases. The following examples assume thatyou have created a database instance from the [:<code>http://files.basex.orglocalhost:8080/xmlrest</factbook.xml factbook.xml] document:code>
:<code>http://localhost:8984/rest</code> <pre classsyntaxhighlight lang="brush:xml"> <rest:databases resources="1" xmlns:rest="http://basex.org/rest"> <rest:database resources="125742" size="181359943813599">factbookarticles</rest:database> ...</rest:databases></presyntaxhighlight> The resources of a database (directories, resource metadata) are listed if a database and an optional directory path is specified:
The resources of a database can be listed by specifying the database, and potential sub directories, in the URL.In the given example, a single XML document is stored in the ''factbook'' database:<code>http://localhost:8080/rest/articles</code>
:<codesyntaxhighlight lang="xml"><database name="articles" xmlns="http://localhost:8984basex.org/rest"> <dir>binaries</factbookdir> <resource type="xml" content-type="application/xml" size="77192">1973-02-08-xltp325.xml</resource> ...</database></codesyntaxhighlight>
<pre class="brush:xml"> <rest:database name="factbook" The {{Code|dir}} elements were introduced with {{Announce|Version 10}}. Before, information on all resources="1" xmlns:rest="http://basex.org/rest"> <rest:resource type="xml" content-type="application/xml" size="77192">factbookwas listed that were located in the specified path or any of its subdirectories.xml</rest:resource></rest:database></pre> The contents of a database can be retrieved by directly addressing the resource:
If a resource is not found, an HTTP response will be generated with :<code>404http://localhost:8080/rest/articles/1973-02-08-xltp325.xml</code> as status code.
Text replacement - "8984" to "8080"
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.
=Usage=
By default, REST services are available at {{Code|http://localhost:89848080/rest/}}. If no default credentials are specified in the URL or when starting the web application, they will be requested by the client ([[Web Application#User Management|see further]]).
A web browser can be used to perform simple GET-based REST requests and display the response. Some alternatives for using REST are listed in the [[#Usage Examples|Usage Examples]].
With {{Announce|BaseX 10}}, results in the {{Code|rest}} namespace will be returned unprefixed:
<syntaxhighlight lang="xml">
<!-- before -->
<rest:databases xmlns:rest="http://basex.org/rest"/>
<!-- before -->
<databases xmlns="http://basex.org/rest"/>
</syntaxhighlight>
=URL Architecture=
A request to the root URL returns all available databases:
If the path to a single resource is specified, the resource itself will be returned:<code>http://localhost:8984/rest/factbook/factbook.xml</code>
==Parameters==
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:89848080/rest/factbook/tmp</code> * Returns the number of documents in a database:<br/><code>http://localhost:8080/rest/database?query=count(.)</code>
* Serializes a document as JSONML:<br/><code>http://localhost:89848080/rest/factbook/factbook.xml?method=json&json=format=jsonml</code>
* <code>US-ASCII</code> is chosen as output encoding, and the query <code>eval.xq</code> is evaluated:<br/><code>http://localhost:89848080/rest?run=eval.xq&encoding=US-ASCII</code>
* The next URL lists all database users that are known to BaseX:<br/><code>http://localhost:89848080/rest?command=show+users</code>
==POST Method==
The body of a POST request is interpreted as XML fragment, which specifies theoperation to perform. The name of the root element determines how the body must conform to a given will be evaluated: * {{Code|commands}}: Run [[REST: POST SchemaCommands#Command Scripts|XML SchemaCommand Script]]* {{Code|query}}: Execute XQuery expression* {{Code|run}}: Run server-side file (query or command script)* {{Code|command}}: Execute single command The root element may be bound to the optional REST namespace.Existing command scripts can be sent to the server without any modifications: * Create an empty database and return database information: <syntaxhighlight lang="xml"><commands> <create-db name='db'/> <info-db/></commands></syntaxhighlight> For the other commands, the following child elements are supported: {| class="wikitable"|-! Name! Description|-| {{Code|text}}| Required; contains the query string, command string, or file to be run|-| {{Code|parameter}}| Serialization parameter (with {{Code|@name}} and {{Code|@value}} attributes)|-| {{Code|option}}| Database option (with {{Code|@name}} and {{Code|@value}} attributes)|-| {{Code|variable}}| Variable bindings|-| {{Code|context}}| Initial context item|}
; Examples
* The following query returns Return the first five city names of the <b>factbook</b> database: <pre classsyntaxhighlight lang="brush:xml"><query rest xmlns="http://basex.org/rest"> <textrest><![CDATA[ (//city/name)[position() <= 5] ]]></text></queryrest></presyntaxhighlight>
* The second query returns the Return string lengths of all text nodes, which that are found in the node that has been specified as initial context node:<pre classsyntaxhighlight lang="brush:xml"><rest:query xmlns:rest="http://basex.org/rest"> <rest:text>for $i in .//text() return string-length($i)</rest:text> <rest:context>
<xml>
<text>Hello</text>
<text>World</text>
</xml>
</rest:context></rest:query></presyntaxhighlight>
* The following request returns Return the registered database users encoded in <code>ISO-8859-1</code>:<pre classsyntaxhighlight lang="brush:xml"><command xmlns="http://basex.org/rest">
<text>show users</text>
<parameter name='encoding' value='ISO-8859-1'/>
</command>
</presyntaxhighlight>
* This example creates Create a new database from the specified input and retains preserve all whitespaces:<pre classsyntaxhighlight lang="brush:xml"><command xmlns="http://basex.org/rest">
<text>create db test http://files.basex.org/xml/xmark.xml</text>
<option name='chop' value='false'/>
</command>
</presyntaxhighlight>
* The last request runs a Bind value to the {{Code|$person}} variable and run query <code>queryfind-person.xq</code> , which must be located in the directory specified by <code>[[Options#WEBPATH{{Option|WEBPATH]]</code>}}:<pre classsyntaxhighlight lang="brush:xml"><run xmlns> <variable name="http://basex.org'person' value='Johannes Müller'/rest"> <text>queryfind-person.xq</text>
</run>
</presyntaxhighlight>
==PUT Method==
; Examples
* A new database with the name <b>XMark</b> is created. If XML input is sent in the HTTP body, the resulting database resource will be called <b>XMark.xml</b>:<br/><code><nowiki>http://localhost:89848080/rest/XMark</nowiki></code>* A new database is created, and no whitespaces will be removed from the passed on XML input:<br/><code><nowiki>http://localhost:89848080/rest/XMark?chop=false</nowiki></code>* The contents of the HTTP body will be taken as input for the document <b>one.xml</b>, which will be stored in the <b>XMark</b> database:<br/><code><nowiki>http://localhost:89848080/rest/XMark/one.xml</nowiki></code>
An HTTP response with status code <code>201</code> (CREATED)
; Example
* The <b>factbook</b> database is deleted:<br/><code><nowiki>http://localhost:89848080/rest/factbook</nowiki></code>* All resources of the <b>XMark</b> database are deleted that reside in the <b>tmp</b> path:<br/><code><nowiki>http://localhost:89848080/rest/XMark/tmp/</nowiki></code>
The HTTP status code <code>404</code> is returned if no database is specified.
; Example
* The following request assigns two variables to a server-side query file <code>mult.xq</code> placed in the HTTP directory:<br/><code>http://localhost:89848080/rest?run=mult.xq&$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[
declare variable $x a as xs:integer external; declare variable $y b as xs:integer external;
<mult>{ $a * $b }</mult>
]]></text>
<variable name="b" value="2"/>
</query>
</presyntaxhighlight>
=Response=
The following three example requests all return <code><a/></code> with <code>application/xml</code> as content-type:
:<code>http://localhost:89848080/rest?query=%3Ca/%3E</code><br/><code>http://localhost:89848080/rest?query=%3Ca/%3E&method=xml</code><br/><code>http://localhost:89848080/rest?query=%3Ca/%3E&media-type=application/xml</code>
=Usage Examples=
<code>org.basex.util.Base64</code> can be used for that purpose:
<pre classsyntaxhighlight lang="brush:java">
import java.net.*;
import org.basex.util.*;
public static void main(String[] args) throws Exception {
// The java URL connection to the resource.
URL url = new URL("http://localhost:89848080/rest/factbook");
// Establish the connection to the URL.
String user = "bob";
String pw ="alice";
// Encode user name username and password pair with a base64 implementation.
String encoded = Base64.encode(user + ":" + pw);
// Basic access authentication header to connection request.
}
}
</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):
;GET
* <code><nowiki>curl -i "http://localhost:89848080/rest/factbook?query=//city/name"</nowiki></code>
;POST
* <code><nowiki>curl -i -X POST -H "Content-Type: application/xml" -d "<query xmlns='http://basex.org/rest'><text>//city/name</text></query>" "http://localhost:89848080/rest/factbook"</nowiki></code>* <code><nowiki>curl -i -X POST -H "Content-Type: application/xml" -T query.xml "http://localhost:89848080/rest/factbook"</nowiki></code>
;PUT
* <code><nowiki>curl -i -X PUT -T "etc/xml/factbook.xml" "http://localhost:89848080/rest/factbook"</nowiki></code>* <code><nowiki>curl -i -X PUT -H "Content-Type: application/json" -T "plain.json" "http://localhost:89848080/rest/plain"</nowiki></code>
;DELETE
* <code><nowiki>curl -i -X DELETE "http://admin:admin@localhost:89848080/rest/factbook"</nowiki></code>
=Changelog=
;Version 10.0
* Updated: Results in the {{Code|rest}} namespace will be returned unprefixed.
* Updated: {{Code|dir}} elements are returned when listing the contents of a database.
;Version 9.0
* Added: Support for command scripts in the [[#POST Method|POST Method]].
* Updated: The REST namespace in the [[#POST Method|POST Method]] has become optional.
;Version 8.1
* Added: support Support for input-specific content-type parameters* Updated: the The [[#GET Method|run operation]] now resolves file paths against the [[Options#RESTPATH{{Option|RESTPATH]] }} option.
;Version 8.0
;Version 7.2
* Removed: direct Direct evaluation of adresses resources with <code>application/xquery</code> as content type
;Version 7.1.1
