The Spotfire Streaming Output Adapter for RabbitMQ Nack allows the system to respond to a message with a negative acknowledgement (NACK) back to the server. A negative acknowledgement tells the server that the message was not processed by this consumer and should optionally be requeued on the server to send to another consumer. The consumer that produces the message tuple must have its Auto Acknowledge message property disabled for this adapter to have affect.
This section describes the properties you can set for this adapter, using the various tabs of the Properties view in StreamBase Studio.
Name: Use this required field to specify or change the name of this instance of this component. The name must be unique within the current EventFlow module. The name can contain alphanumeric characters, underscores, and escaped special characters. Special characters can be escaped as described in Identifier Naming Rules. The first character must be alphabetic or an underscore.
Operator: A read-only field that shows the formal name of the operator.
Class name: Shows the fully qualified class name that implements the functionality of this operator. 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 options: This field provides a link to the Cluster Aware tab, where you configure the conditions under which this operator starts.
Enable Error Output Port: Select this checkbox 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 purpose and function of the component. In the EventFlow Editor canvas, you can see the description by pressing Ctrl while the component's tooltip is displayed.
| Property | Type | Description |
|---|---|---|
| RabbitMQ Configuration | Edit Button | Shortcut to the StreamBase Configuration File Editor, used for adapter configuration or converting an existing application's adapter-configurations.xml file to HOCON format.
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| Enable Status On Success | check box | When enabled the adapter will send out a status message for every successful message the is Nacked. |
| Enable Status Port | check box | When enabled the adapter will send out informational data on the status port about various states of the adapter. |
| Log Level | INFO | Controls the level of verbosity the adapter uses to issue informational traces to the console. This setting is independent of the containing application's overall log level. Available values, in increasing order of verbosity, are: OFF, ERROR, WARN, INFO, DEBUG, TRACE. |
Use the settings in this tab to enable this operator or adapter for runtime start and stop conditions in a multi-node cluster. During initial development of the fragment that contains this operator or adapter, and for maximum compatibility with releases before 10.5.0, leave the Cluster start policy control in its default setting, Start with module.
Cluster awareness is an advanced topic that requires an understanding of StreamBase Runtime architecture features, including clusters, quorums, availability zones, and partitions. See Cluster Awareness Tab Settings on the Using Cluster Awareness page for instructions on configuring this tab.
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.
Caution
Concurrency settings are not suitable for every application, and using these settings requires a thorough analysis of your application. For details, see Execution Order and Concurrency, which includes important guidelines for using the concurrency options.
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channel, integer. The channel ID on which to send the Nack. This value is output by the consumer adapter.
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envelope.deliveryTag, tuple<long>. The deliveryTag of the message to Nack. This value is output by the consumer adapter.
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multiple (optional), boolean. An optional field that determines whether the server should Nack just this message (false) or all previous as well (true). If this value is missing or null false is used.
The status port is used to send status information tuples downstream to inform the user of changes.
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type, string. The type of status information emitted on this port. Status types are:
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Error—Indicates this message is related to an error that occurred.
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Warn—Indicates this message is related to a warning that the user should be aware of.
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Info—Indicates this message is related to extra status information.
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action, string. Always Nack
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object, string. This value may be null. If not null, it contains a value relevant to the status message.
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message, string. This is a formatted human readable message that explains the status message.