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:documentationPath: /pipeline/transforms/
:language: en_US
:description: The HTTP Client transform performs a simple call to a base URL with additional options.

= image:transforms/icons/http.svg[HTTP client transform Icon, role="image-doc-icon"] HTTP client

[%noheader,cols="3a,1a", role="table-no-borders" ]
|===
|
== Description

The HTTP Client transform performs a simple call to a base URL with additional options.

====
http://<URL>?param1=value1&amp;param2=value2&amp;param3..
====

The result is stored in a String field with the specified name.

|
== Supported Engines
[%noheader,cols="2,1a",frame=none, role="table-supported-engines"]
!===
!Hop Engine! image:check_mark.svg[Supported, 24]
!Spark! image:question_mark.svg[Maybe Supported, 24]
!Flink! image:question_mark.svg[Maybe Supported, 24]
!Dataflow! image:question_mark.svg[Maybe Supported, 24]
!===
|===

== Options

[options="header"]
|===
|Option|Description
|Transform name|Name of the transform; this name has to be unique in a single pipeline
|URL|The base URL string
|Accept URL from field?|Enable this option if you want to get the URL from a previous transform.
Enabling this will also allow you to specify the name of the input field.
|URL field name|The name of the incoming field that contains the URL
|Connection timeout|
|Socket timeout|The number of seconds to wait if no data is returned from the server.
|Connection close wait time |
|Result fieldname|The name of the field to store results
|HTTP status code field name|The name of the field to store the HTTP response code (e.g. 200, 404)
|Response time (milliseconds) field name|The name of the field to store the response time
|Http Login|The username to be passed during HTTP (Basic) authentication
|HTTP Password|The password to be passed during HTTP (Basic) authentication
|Proxy Host|The hostname of the Proxy Server to be used
|Proxy Port|The port number of the Proxy Server to be used
|Parameters|Area where you define the parameter name-value pairs to pass on the URL
|Custom HTTP Headers|Area where you define optional HTTP headers
|===

== FAQ

=== The HTTP client transform doesn't do anything

*Q*: The HTTP client transform doesn't do anything, how do I make it work?

*A*: The HTTP client transform needs to be triggered.
Use a Row generator transform generating e.g. 1 empty row and link that with a hop to the HTTP client transform.

=== The HTTP client transform and SOAP

*Q*: Does the HTTP client support SOAP?

*A*: No, it just calls an URL with arguments.
Future transforms may provide SOAP functionality, Work is underway on a WebService transform supporting WSDL.
