Web Output Adapter

Introduction

The TIBCO StreamBase® Web Output Adapter allows the system to stream tuple data in JSON format to one or more connected websockets. When this adapter is placed on the canvas, it will take the schema of the input port and create a WebSocket endpoint based on the fully qualified path of the adapter, unless specified by the context path property. For example, if the adapter's path including the container name is default.module1.weboutput then a WebSocket endpoint is created at http://localhost:10090/default/module1/weboutput using the default 10090 port. A default web page is created at the root which lists all available endpoints and their schemas. The root endpoint also provides a test page for each endpoint. To view the default page, visit http://localhost:10090 when your application is running.

Adapter Properties

This section describes the properties you can set for this adapter, using the various tabs of the Properties view in StreamBase Studio.

General Tab

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.

Adapter Properties Tab

Property Type Description
Id Field string The field in the incoming tuple which represents the ID of the websocket to send this tuple. If this field is not set or is null or empty, then the tuple is sent to all connections.
Context Path string The context path for this websocket endpoint, if empty the fully qualified container path of this operator will be used.
Timestamp Format string The timestamp format used to convert timestamp fields to JSON.

WebSocket Protocol

This section describes how the WebSocket protocol works.

Input

Once connected, the only message the websocket accepts is a JSON-formatted string to set the websocket's ID.

The ID field is used when input tuples also contain an ID field, and if they match the tuple is sent to this websocket. If no ID is set for this websocket, then only tuples with no ID field set or a null or empty ID field is sent to this websocket.

Example message: {"id":"7080AA07-5C01-4F8D-BB40-5B9C47F757BB"}

Output

Once connected, the adapter starts sending tuples received on its input port to connected websockets. Tuples are converted from a tuple to a JSON-formatted string before sending. To preserver bandwidth, the JSON will not include any null fields.

Configuration

Description

The adapter works with default configuration. If you want to modify how the adapter works, you can use the adapter configuration section that starts with the <adapter-configurations> element and containing one <adapter-configuration name="webstreams"> element, which itself contains exactly one <section name="webstreams"> element.

Only exactly one of these configurations is allowed per application, which all adapters will use if found.

This example configuration shows a web server that contains all available values.

Example

<adapter-configurations>
  <adapter-configuration name="webstreams">
    <section name="webstreams">
      <setting name="Enabled" val="true" />                
      <setting name="Port" val="10090" />                
      <setting name="IdleTimeoutMS" val="0" />                
      <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="0" />
      <setting name="WebSocketIdleTimeoutMS" val="0" />                
      <setting name="SecurePort" val="10443" />
      <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>
  </adapter-configuration>        
</adapter-configurations>         

Settings

Setting Type Description
Enabled true/false If true the web server and all ports are started. If false no web server is started and all operators become no-ops.
Port integer The port the web server will listen on for connections.
IdleTimeoutMS integer The amount of time in milliseconds to wait for connections to send data.
OutputBufferSize integer Set the size of the buffer into which response content is aggregated before being sent to the client.
RequestHeaderSize integer Set the maximum size of a request header.
ResponseHeaderSize integer Set the maximum size of a response header.
SendServerVersion true/false If true, send the Server header in responses.
SendDateHeader true/false If true, include the date in HTTP headers.
SelectorThreads int The number of selector threads, or less than or equal to 0 for a default value. Selectors notice and schedule established connection that can make IO progress.
AcceptorThreads int The number of acceptor threads to use, or -1 for a default value. Acceptors accept new TCP/IP connections. If 0, then the selector threads are used to accept connections.
ReuseAddress true/false Whether the server socket reuses addresses.
LingerTime integer The linger time. Use -1 to disable.
GZipMimeTypes string Set the mime types associated with GZip requests. Blank or missing means do not use GZip.
WebSocketAsyncWriteTimeoutMS integer The time in milliseconds before a write command times out.
WebSocketIdleTimeoutMS integer The time in milliseconds before a web socket times out from idle behavior.
SecurePort integer Set the TCP/IP port used for CONFIDENTIAL and INTEGRAL redirections.
* SSLKeyStorePath string The file or URL of the SSL Key store.
* SSLKeyStorePassword string The password for the key store.
* SSLKeyStoreManagerPassword string The password (if any) for the specific key within the key store.
* SSLTrustStorePath string The file name or URL of the trust store location.
* SSLTrustStorePassword string The password for the trust store.

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