HTTP connector provides connectivity to web servers over HTTP protocol and supports common HTTP operations like GET, POST, PUT, and DELETE. It can be used to invoke services over HTTP or HTTPS and can be used to invoke standard web services or REST based services with XML or JSON payloads.

It has the following features which help applications to communicate with the external web servers.

Support multiple servers

Using the same HTTP connector or container, you can connect to multiple hosts and invoke services. These services can be internal to the organization or available in the internet. HTTP connector configuration has connection details of various servers, identified by a name or ID that is unique. While processing the request, you must provide the connection ID that helps the connector to identify proper connection details.

A sample configuration in the XML store is as follows:

<configurations xmlns="http://httpconnector.opentext.com/1.0/configuration">
    <connections>
        <connection id="CONN-DELICIOUS-FEED">
            <url>http://feeds.delicious.com</url>
        </connection>
    </connections>
    <connections>
        <connection id="PRocess-PLATFORM-TASKS">
            <url>http://myserver:9123/cordys</url>
			<username>testuser</username>
			<password>YzByZHlz</password>
        </connection>
    </connections>
</configurations>

Organization aware behavior

By default, HTTP connector is organization-aware. The same HTTP connector in the shared space or system organization can be used to process requests from organizations or tenants with organization-specific configuration. The HTTP connector configuration is stored in the XML store, which by default is organization-aware. Based on the organization context of the user, the configuration is selected. If the configuration is available in a specific organization, HTTP connector uses the configuration available in that organization, else HTTP connector uses configuration available in the shared space.

Supports invoking standard web services and REST services

HTTP connector follows a pluggable request and response handling architecture. It supports web services with XML payload and REST-based services with JSON and XML payloads.

For standard web services,

<implementation type= "HTTP" xmlns= "http://httpconnector.opentext.com/1.0/implementation"  xmlns:SOAP= "http://schemas.xmlsoap.org/soap/envelope/"  >
......
<request-handler  class = "com.opentext.applicationconnector.httpconnector.impl.StandardRequestHandler" />
<response-handler  class = "com.opentext.applicationconnector.httpconnector.impl.StandardResponseHandler" />
....
</implementation >

For REST services,

<implementation type= "HTTP" xmlns= "http://httpconnector.opentext.com/1.0/implementation"  xmlns:SOAP= "http://schemas.xmlsoap.org/soap/envelope/"  >
......
<request-handler  class = "com.opentext.applicationconnector.httpconnector.impl.RestRequestHandler" />
<response-handler  class = "com.opentext.applicationconnector.httpconnector.impl.RestResponseHandler" />
....
</implementation >

Multiple payload format

HTTP connectors can send input to services or receive output from services either in the XML or JSON format. Since Process Platform supports only SOAP based web services, all requests from Platform are in SOAP or XML format and HTTP connector transforms them to appropriate format.

If the input request is of the type HTTP POST and expects a JSON input, then set Content-type=application/json in the request header, as follows:

<implementation xmlns= "http://httpconnector.opentext.com/1.0/implementation"  xmlns:SOAP= "http://schemas.xmlsoap.org/soap/envelope/"  type= "HTTP" >
........................
<connection-id>JSON-TEST</connection-id> 
<request-handler  class = "com.opentext.applicationconnector.httpconnector.impl.RestRequestHandler" >
<req-headers>
<header name= "Content-Type" >application/json</header>
</req-headers> 
</request-handler>
<response-handler  class = "com.opentext.applicationconnector.httpconnector.impl.RestResponseHandler" />
<valid-response-code> 200 </valid-response-code>
................
</implementation>

Request and response transformation capability

You can use XSLT capability to transform a request to another request that is expected by the service or to transform the response from the service to the XML expected by the application. The XSLT can be stored in the XML store and can be used inside the HTTP connector. This can be done as follows:

<implementation xmlns= "http://httpconnector.opentext.com/1.0/implementation"  xmlns:SOAP= "http://schemas.xmlsoap.org/soap/envelope/"  type= "HTTP" >
........................
<connection-id>JSON-TEST</connection-id> 
<request-handler  class = "com.opentext.applicationconnector.httpconnector.impl.RestRequestHandler" >
<req-headers>
<header name= "Content-Type" >application/json</header>
</req-headers>
<xslt xmlstore= "xslts/request.xslt" /> 
</request-handler>
<response-handler  class = "com.opentext.applicationconnector.httpconnector.impl.RestResponseHandler" >
<xslt xmlstore= "xslts/response.xslt" />
</response-handler>
<valid-response-code> 200 </valid-response-code>
................
</implementation>

Authentication support

Though HTTP connector supports basic authentication, it also supports HTTPS.

Custom HTTP header support

You can add custom HTTP headers to the request while sending request.

<request-handler  class = "com.opentext.applicationconnector.httpconnector.impl.RestResponseHandler" >
...
<req-headers>
<header name= "x-ms-version" > 2012 - 03 - 01 </header>
<header name= "Content-Type" >application/xml</header>
</req-headers>
..
</request-handler>

 <implementation type="HTTP" xmlns="http://httpconnector.opentext.com/1.0/implementation" xmlns:SOAP="http://schemas.xmlsoap.org/soap/envelope/">
    <connection-id>CONN-DELICIOUS-FEED</connection-id>
    <http-method>GET</http-method>
    <uri>/v2/rss/{0}</uri>
    <request-handler class="com.opentext.applicationconnector.httpconnector.impl.RestRequestHandler">
        <uri-parameters>
            <parameter type="xpath">./Username</parameter>
        </uri-parameters>
    </request-handler>
    <response-handler class="com.opentext.applicationconnector.httpconnector.impl.StandardResponseHandler"/>
    <valid-response-code>200</valid-response-code>
    <namespaces/>
</implementation>

<SOAP:Envelope xmlns:SOAP="http://schemas.xmlsoap.org/soap/envelope/">
    <SOAP:Body>
        <GetBookmarksForUser xmlns="http://com.opentext.httptest/rest">
            <Username>RestUser</Username>
        </GetBookmarksForUser>
    </SOAP:Body>
</SOAP:Envelope>