tRESTRequest Standard properties

Initialize from OAS/Swagger 2.0 API definition / Definition file

Click [...] to browse to the OAS/Swagger 2.0 file to initialize your component endpoint, API mappings and documentation from your API definition.

REST Endpoint

Fill this field with the URI location where REST-ful web service will be accessible for requests. You can either specify an explicit port number, for example, "http://localhost:8088/services/customers", or use the default port of Talend and specify the relative path only, for example, "/services/customers".

If you have installed the R2020-05 Studio Monthly update or a later one delivered by Talend, you can define the endpoint using context variables. For more information about Studio Monthly update, check with your administrator.

REST API Mapping

Click the [+] button beneath the mapping table to add lines to specify HTTP request:

Output Flow: Click the [...] button to specify the name of an output flow and set the schema for that output flow in the dialog box afterwards.

The schema is not mandatory, so if you do not need to pass additional parameters to the tRESTRequest component, you can leave the schema empty. However, you will have to populate the schema if you have URI Path parameters set in the URI Pattern field or if you need to add optional request parameters such as URI Query, HTTP Header or Form parameters, to the URI specified in the REST Endpoint field.

Add a schema with the name body to get the request body of POST and PUT methods. It supports Document, String, and Byte types.

HTTP Verb: Select a HTTP method (GET/POST/PUT/PATCH/DELETE/OPTIONS/HEAD) from the list.

URI pattern: Fill this field with REST-ful URIs that describe the resource.

Consumes: Select the format type of the consume content that the component will use from XML or JSON, XML, JSON, Form, Multipart and Any in the list when the HTTP method is POST, PUT or PATCH.

Produces: When the HTTP method is GET, POST, PUT, PATCH, or DELETE, select the format type of the produce content that the component will use from XML or JSON, XML, JSON, HTML and Any, or select <oneway> in the list to accept one way requests.

Streaming: Select this check box to stream the response data by chunks so that the large volumes of data can be processed efficiently.

Use Authentication (ESB runtime only)

Select this check box to enable the authentication option for the current service. This option works in runtime only. Select the authentication type from:

• Basic HTTP: The simplest technique for enforcing access controls to web resources using standard fields in the HTTP header.
• SAML Token: An XML-based, open-standard data format for exchanging authentication and authorization data between an identity provider and a service provider.
• Open ID Connect: An extension for OAuth2 which allows Clients to verify the identity of the End-User based on the authentication performed by an Authorization Server, as well as to obtain basic profile information about the End-User in an interoperable and REST-like manner. For more information, see Talend Identity and Access Management and Managing ESB Resources and authorizations.

Use Authorization

Select this check box to enable authorized call. This option appears when SAML Token (ESB runtime only) is selected in the Use Authentication list.

For more information about the management of user roles and rights, see the Talend Administration Center User Guide and Talend ESB Infrastructure Services Configuration Guide.

Use Business Correlation

Select this check box to enable the correlation option so that chained service calls will be grouped under the same correlation ID. tRESTRequest will extract the correlation ID from the request header and store it in the component variable for further use in the flow.

If this option is not enabled on the client side, a correlation ID will be generated automatically in tRESTRequest.

Expose Swagger specification

This option appears when tRESTRequest is used as a service provider. Select this check box to expose the Swagger specification and include the Swagger UI into the REST service, which provides an online API Documentation in human-readable form and some basic test features.

If the Job is running in the Studio, the Swagger specification will be available at http://127.0.0.1:8090/services/SERVICE_NAME/swagger.json and http://127.0.0.1:8090/services/SERVICE_NAME/swagger.yaml. The Swagger UI is not available.

If the Job is deployed in Talend Runtime, the Swagger specification will be available at http://127.0.0.1:8040/services/SERVICE_NAME/swagger.json and http://127.0.0.1:8040/services/SERVICE_NAME/swagger.yaml. The Swagger UI will be available at http://127.0.0.1:8040/services/SERVICE_NAME/api-docs?url=/services/SERVICE_NAME/swagger.json.

Include Documentation into Swagger Spec

This option appears when tRESTRequest is used as a service provider and the Expose Swagger specification check box is selected. Select this option to add content in the Comment field of the Documentation tab of this component into the Swagger specification and the Swagger UI page.

For more information about the Documentation tab, see Talend Studio User Guide.

tStatCatcher Statistics

Select this check box to gather the Job processing metadata at a Job level as well as at each component level.

Global Variables

NB_LINE: the number of rows processed. This is an After variable and it returns an integer.

URI: the URI of the REST request. This is a Flow variable and it returns a string.

URI_BASE: the base URI of the REST request. This is a Flow variable and it returns a string.

URI_ABSOLUTE: the absolute URI of the REST request. This is a Flow variable and it returns a string.

HTTP_METHOD: the http method. This is a Flow variable and it returns a string.

ATTACHMENT_HEADERS: the attachment headers from the REST request. This is a Flow variable and it returns a list of attachment header values.

ATTACHMENT_FILENAMES: the attachment filenames from the REST request. This is a Flow variable and it returns all attachment filenames.

PRINCIPAL_NAME: the principal name of the REST request. This is a Flow variable and it returns a string.

CORRELATION_ID: the correlation ID by which chained service calls will be grouped. This is a Flow variable and it returns a string.

ERROR_MESSAGE: the error message generated by the component when an error occurs. This is an After variable and it returns a string. This variable functions only if the Die on error check box is cleared, if the component has this check box.

A Flow variable functions during the execution of a component while an After variable functions after the execution of the component.

To fill up a field or expression with a variable, press Ctrl + Space to access the variable list and choose the variable to use from it.

For further information about variables, see Talend Studio User Guide.

Usage rule

This component covers the possibility that a Talend Job can be wrapped as a service, with the ability to input a request to a service into a Job and return the Job result as a service response.

The tRESTRequest component should be used with the tRESTResponse component to provide a Job result as a response, in case of a request-response communication style.

Limitation

Using context variables for dynamic endpoint or Service Locator namespace works in the Studio only. It is not supported in Runtime.