1. Stream Analytics Documentation
  2. Manage
  3. Streams
  4. Create Streams
  5. Creating a JMS Stream

4.2.1.3 Creating a JMS Stream

Prerequisite: A JMS connection.

To create a JMS stream:

  1. On the Catalog page, click Create New Item.
  2. Hover the mouse over Stream and select JMS from the submenu.
  3. On the Type Properties screen, enter the following details:
    • Name: Enter a unique name for the stream. This is a mandatory field.
    • Display Name: Enter a display name for the stream. If left blank, the Name field value is copied.
    • Description
    • Tags
    • Stream Type: The selected stream is displayed.
  4. Click Next.
  5. On the Source Type page, enter the following details:

    • Connection: Select an existing JNDI connection for the stream

    • Connection Factory: Enter a value for the connection factory. A ConnectionFactory encapsulates connection configuration information, and enables JMS applications to create a Connection. The default value is weblogic.jms.ConnectionFactory.

      Note:

      GGSA can read messages from Oracle Advanced Queue. This option is available as a general JMS connector - oracle.jms.AQjmsInitialContextFactory.

    • Jndi name: Enter the name of the Java interface that reads messages from topics, distributed topics, queues and distributed queues

    • Client ID: Enter the unique client ID to be used for a durable subscriber. If you do not provide this value, subscriber ID is used as a clientID to create a durable subscriber.

    • Message Selector : Set the message selector to filter messages. Message selectors assign the work of filtering messages to the JMS provider rather than to the application.

      If your messaging application needs to filter the messages it receives, you can use a JMS API message selector. A message selector is a String that contains an expression. The syntax of the expression is based on a subset of the SQL92 conditional expression syntax. The message selector in the following example selects any message that has a NewsType property that is set to the value Sports or Opinion: 

      NewsType = ’Sports’ OR NewsType = ’Opinion’

      The createConsumer and createDurableSubscriber methods allow you to specify a message selector as an argument when you create a message consumer.

    • Subscription ID: Enter the unique subscription ID for durable selector. This value is essential for durable subscriber.

      Note:

      When you specify both clientID and subscriberID, you can have only one running pipeline consuming that stream. If you need multiple subscribers/pipelines, remove clientID or subscriberName from the stream or create different streams (with different clientID and subscriberName) for multiple pipelines.

    • Data Format: Select the data format from the drop-down list. The supported formats are: CSV, JSON, AVRO, MapMessage.

      A MapMessage object is used to send a set of name-value pairs. The names are String objects, and the values are primitive data types in the Java programming language. The names must have a value that is not null, and not an empty string. The entries can be accessed sequentially or randomly by name. The order of the entries is undefined.

  6. Click Next.
  7. On the Data Format screen, enter the shape details for the stream, based on the data format you have selected.
    • For JSON:
      • Allow Missing Column Names: Select this option to allow an input stream that has a column undefined in the shape.
    • For CSV:
      • CSV Predefined Format: Select one of the predefined data format from the drop-down list. For more information, see Predefined CSV Data Formats.
      • First record as header: Select this option to use the first record as the header row.
    • For AVRO:
      • Schema Namespace: Enter the schema name combined with the namespace, to uniquely identify the schema within the store.
      • Schema (optional): Upload a schema file to infer shape from.
    • If you selected MapMessage as the data format, there are no specific attributes to be set on this screen. The Data Format screen is skipped, and you are redirected to the Shape screen.
  8. Click Next.
  9. On the Shape screen, select one of the methods to define the shape:

    • Infer Shape : Select this option to detect the shape automatically from the input data stream.

    • Select Existing Shape: Select one of the existing shapes from the drop-down list.

    • Manual Shape: Select this option to manually infer the fields from a stream or file. You can also update the datatype of the fields.

      Note:

      • To retrieve the entire JSON payload, add a new field with path $.
      • To retrieve the content of the array, add a new field with path $[arrayField].

      In both the cases, the value returned is of type Text.

    • From File: Select this option to infer the shape from a JSON schema file, or a JSON or CSV data file. You can also save the auto-detected shape and use it later.
  10. Click Save.

JMS Server Clean-Up

GGSA creates a durable subscription with the JMS provider, when you create a JMS stream and select the durable subscription option. When you unpublish or kill a pipeline that is using this stream, the durable subscription still remains on the JMS Server. It is advisable to delete the durable subscription from the JMS Server and clean up the resources, if you do not intend to publish the pipeline anymore.