Web Server Request Adapter

Name: Use this required field to specify or change the name of this instance of this component, which must be unique in the current EventFlow module. The name must contain only alphabetic characters, numbers, and underscores, and no hyphens or other special characters. The first character must be alphabetic or an underscore.

Adapter: A read-only field that shows the formal name of the adapter.

Class name: Shows the fully qualified class name that implements the functionality of this adapter. If you need to reference this class name elsewhere in your application, you can right-click this field and select Copy from the context menu to place the full class name in the system clipboard.

Start with application: If this field is set to Yes (default) or to a module parameter that evaluates to true, this instance of this adapter starts as part of the JVM engine that runs this EventFlow module. If this field is set to No or to a module parameter that evaluates to false, the adapter instance is loaded with the engine, but does not start until you send an sbadmin resume command, or until you start the component with StreamBase Manager.

Enable Error Output Port: Select this check box to add an Error Port to this component. In the EventFlow canvas, the Error Port shows as a red output port, always the last port for the component. See Using Error Ports to learn about Error Ports.

Description: Optionally enter text to briefly describe the component's purpose and function. In the EventFlow canvas, you can see the description by pressing Ctrl while the component's tooltip is displayed.

Use the Concurrency tab to specify parallel regions for this instance of this component, or multiplicity options, or both. The Concurrency tab settings are described in Concurrency Options, and dispatch styles are described in Dispatch Styles.

Use the control port to send action commands to the adapter. Tuples enqueued on this port cause the adapter to start or stop a server.

The status port is used to send status information tuples downstream to inform the user of changes.

The web server adapter configuration section starts with an <adapter-configurations> element containing one <adapter-configuration name="webservers"> element that contains one or more <section name="webserver"> elements.

Each <section name="webserver"> configuration must contain a <setting name="id" val="Web Server Port nnnn"/> and <setting name="Port" val="nnnn"/> settings fields. All other setting elements are optional.

This example configuration shows two different web servers. The first contains all values available and the second shows the required values. You can have as many configurations as your application requires, but each must have a unique port number and a unique ID.

<adapter-configurations>
  <adapter-configuration name="webservers">
    <section name="webserver">
       <setting name="id" val="Web Server Port 8080"/>
       <setting name="Port" val="8080"/>                
       <setting name="StartOnStartup" val="true"/>
       <setting name="IdleTimeoutMS" val="30000"/>                
       <setting name="OutputBufferSize" val="32768"/>
       <setting name="RequestHeaderSize" val="8192"/>
       <setting name="ResponseHeaderSize" val="8192"/>
       <setting name="SendServerVersion" val="true"/>
       <setting name="SendDateHeader" val="false"/>
       <setting name="SelectorThreads" val="-1"/>
       <setting name="AcceptorThreads" val="-1"/>
       <setting name="ReuseAddress" val="true"/>
       <setting name="LingerTime" val="-1"/>
       <setting name="GZipMimeTypes" val="text/html,text/plain,text/xml,
          application/xhtml+xml,text/css,application/javascript,text/javascript,
          image/svg+xml"/>                
       <setting name="WebSocketAsyncWriteTimeoutMS" val="5000"/>
       <setting name="WebSocketIdleTimeoutMS" val="30000"/>                
       <setting name="SecurePort" val="8443"/>
       <setting name="SSLKeyStorePath" val="keystore"/>
       <setting name="SSLKeyStorePassword" val="tester"/>
       <setting name="SSLKeyStoreManagerPassword" val="tester"/>
       <setting name="SSLTrustStorePath" val="keystore"/>
       <setting name="SSLTrustStorePassword" val="tester"/>
    </section>
    <section name="webserver">
      <setting name="id" val="Web Server Port 9090"/>
      <setting name="Port" val="9090"/>
    </section>
  </adapter-configuration>        
</adapter-configurations>

* NOTE: Refer to http://wiki.eclipse.org/Jetty/Howto/Configure_SSL when setting up SSL.

package com.streambase.sb.adapter.webserver.data;

import java.util.Map;

import javax.servlet.http.HttpServletRequest;

import org.eclipse.jetty.server.Request;
import org.slf4j.Logger;

import com.streambase.sb.Schema;
import com.streambase.sb.StreamBaseException;
import com.streambase.sb.operator.TypecheckException;

public interface IRequestDataTransformer {
    /***
     * This method will be called during typecheck time to allow a request data transformer 
     * to validate a key value map of settings against the transformer 
     * @param settings A key value map of settings the end user specified for this adapters 
     * custom data transformation
     * @param schema The schema provided by the end user for which the data should be converted to. 
     * @throws TypecheckException
     */
    public void validateSettings(Map<String, String> settings, Schema schema) throws TypecheckException;
    
    /***
     * This method allows the HTTP request data to be transformed into a tuple with any custom logic required
     * 
     * NOTE: only one of the two readers can be used (httpServletRequest or request) once one is read the 
     * other will become invalid
     * 
     * @param sender The senders methods are used to send completed tuples downstream.  It is expected 
     * that for each call to this method at least 1 tuple is create and a sendTuple or sendTupleAsync is called.
     * @param logger A logger than can be used to log any extra information which may be required
     * @param settings A key value map of settings the end user specified for this adapters custom data 
     * transformation 
     * @param schema The schema provided by the end user for which the data should be converted to.
     * @param httpServletRequest The HTTP request to use for transform into a tuple
     * @param request The base HTTP request to use for transforming into a tuple
     * @throws StreamBaseException
     */
    public void transformRequestData(IRequestDataTupleSender sender, Logger logger, Map<String, String> settings, 
    Schema schema, HttpServletRequest httpServletRequest, Request request) throws StreamBaseException;
}         

package com.streambase.sb.adapter.webserver.data;

import com.streambase.sb.Tuple;

/***
 * The request data tuple sender is used to send a tuple downstream after parsing the HTTP request into a tuple.
 * 
 * It is recommended that if you expect to send more than one tuple per http request that you mark a single tuple 
 * to send as the response.  
 * Sending more than one tuple for the same request into the response web server adapter will fail.
 */
public interface IRequestDataTupleSender {
    /***
     * Send a tuple downstream and wait for its execution to fully complete 
     * @param tuple The tuple to set as the request data tuple
     */
    public void sendTuple(Tuple tuple);
    
    /***
     * Send a tuple downstream asynchronously 
     * @param tuple The tuple to set as the request data tuple
     */
    public void sendTupleAsync(Tuple tuple);
}          

The JSON request data transform converts a JSON request to a tuple.

The XML request data transform converts an XML request to a tuple.

The Binary request data transform converts a request to a series of tuples containing the request POST data.

This transformer requires the request schema and contains three fields: Data of type Blob, Name of type String, and Value of type String.

The data field contains any data from the body. The Value field will contain any values from form fields.

This adapter will output 1-N number of tuples containing the request body data. After reading all the body data, a tuple with all null fields is emitted to represent the completion.