Google Pub Sub Publish Message activity¶
Introduction¶
A Google Pub Sub Publish Message activity, using its Google Pub Sub connection, publishes messages to a topic in Google Pub/Sub and is intended to be used as a target to consume data in an operation.
Create a Google Pub Sub Publish Message activity¶
An instance of a Google Pub Sub Publish Message activity is created from a Google Pub Sub connection using its Publish Message activity type.
To create an instance of an activity, drag the activity type to the design canvas or copy the activity type and paste it on the design canvas. For details, see Creating an activity instance in Component reuse.
An existing Google Pub Sub Publish Message activity can be edited from these locations:
- The design canvas (see Component actions menu in Design canvas).
- The project pane's Components tab (see Component actions menu in Project pane Components tab).
Configure a Google Pub Sub Publish Message activity¶
Follow these steps to configure a Google Pub Sub Publish Message activity:
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Step 1: Enter a name and specify a topic
Provide a name for the activity and select a topic. -
Step 2: Review the data schemas
Any request or response schemas generated from the endpoint are displayed.
Step 1: Enter a name and specify a topic¶
In this step, provide a name for the activity and specify a subscription. Each user interface element of this step is described below.
The interface used in this step of the configuration of a Google Pub Sub Publish Message activity depends on the Choose Subscription option selected:
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Inform topic manually: For this option, you will manually enter the topic where the messages are to be published.
-
Select existent topic: This option will populate a list of existing topics to choose from. To use this option, you must have the
pubsub.topics.list
assigned to the service account specified in the Google Pub Sub connection.
Inform topic manually¶
If Inform Topic Manually is selected for Choose Topic, this interface is presented:
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Name: Enter a name to identify the activity. The name must be unique for each Google Pub Sub Publish Message activity and must not contain forward slashes
/
or colons:
. -
Choose Subscription: Select the method for providing the topic to be used in the request:
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Inform Topic Manually: Select to manually enter the topic where the messages are to be published.
-
Select Existent Topic: Select to choose an existing topic from a populated list. To use this option, you must have the
pubsub.topics.list
permission assigned to the service account specified in the Google Pub Sub connection.
-
-
Topic: Enter the name of the topic where the messages are to be published.
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Continue on Error: Select to continue the activity execution if an error is encountered for a dataset in a batch request. If any errors are encountered, they are written to the operation log.
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Save & Exit: If enabled, click to save the configuration for this step and close the activity configuration.
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Next: Click to temporarily store the configuration for this step and continue to the next step. The configuration will not be saved until you click the Finished button on the last step.
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Discard Changes: After making changes, click to close the configuration without saving changes made to any step. A message asks you to confirm that you want to discard changes.
Select existent topic¶
If Select Existent Topic is selected for Choose Topic, this interface is presented:
-
Name: Enter a name to identify the activity. The name must be unique for each Google Pub Sub Publish Message activity and must not contain forward slashes
/
or colons:
. -
Choose Subscription: Select the method for providing the topic to be used in the request:
-
Inform Topic Manually: Select to manually enter the topic where the messages are to be published.
-
Select Existent Topic: Select to choose an existing topic from a populated list. To use this option, you must have the
pubsub.topics.list
permission assigned to the service account specified in the Google Pub Sub connection.
-
-
Select a Topic: This section displays topics available in the Google Pub Sub endpoint.
- Selected Topic: After a topic is selected, it is listed here.
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Search: Enter any column's value into the search box to filter the list of topics. The search is not case-sensitive. If topics are already displayed within the table, the table results are filtered in real time with each keystroke. To reload topics from the endpoint when searching, enter search criteria and then refresh, as described below.
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Refresh: Click the refresh icon or the word Refresh to reload topics from the Google Pub Sub endpoint. This may be useful if topics have been added to Google Pub/Sub. This action refreshes all metadata used to build the table of topics displayed in the configuration.
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Selecting a Topic: Within the table, click anywhere on a row to select a topic. Only one topic can be selected. The information available for each topic is fetched from the Google Pub Sub endpoint:
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Name: The name of the topic.
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Description: The description of the topic.
Tip
If the table does not populate with available topics, the Google Pub Sub connection may not be successful. Ensure you are connected by reopening the connection and retesting the credentials.
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Continue on Error: Select to continue the activity execution if an error is encountered for a dataset in a batch request. If any errors are encountered, they are written to the operation log.
-
Save & Exit: If enabled, click to save the configuration for this step and close the activity configuration.
-
Next: Click to temporarily store the configuration for this step and continue to the next step. The configuration will not be saved until you click the Finished button on the last step.
-
Discard Changes: After making changes, click to close the configuration without saving changes made to any step. A message asks you to confirm that you want to discard changes.
Step 2: Review the data schemas¶
Any request or response schemas generated from the endpoint are displayed. Each user interface element of this step is described below.
-
Data Schemas: These data schemas are inherited by adjacent transformations and are displayed again during transformation mapping.
The Google Pub Sub connector uses the Google Pub/Sub API. Refer to the API documentation for information on the schema nodes and fields.
Note
The response schema for the Publish Message activity will vary depending on the configuration of the Topic selected in Step 1: Enter a name and select a topic. If the selected topic has a configured schema, the request schema will have a
body
node with the same structure as the configured schema in Google Pub/Sub. If the selected topic does not have a configured schema, the request schema will have abody
field that accepts string data (shown above). -
Refresh: Click the refresh icon or the word Refresh to regenerate schemas from the Google Pub Sub endpoint. This action also regenerates a schema in other locations throughout the project where the same schema is referenced, such as in an adjacent transformation.
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Back: Click to temporarily store the configuration for this step and return to the previous step.
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Finished: Click to save the configuration for all steps and close the activity configuration.
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Discard Changes: After making changes, click to close the configuration without saving changes made to any step. A message asks you to confirm that you want to discard changes.
Next steps¶
After configuring a Google Pub Sub Publish Message activity, complete the configuration of the operation by adding and configuring other activities, transformations, or scripts as operation steps. You can also configure the operation settings, which include the ability to chain operations together that are in the same or different workflows.
Menu actions for an activity are accessible from the project pane and the design canvas. For details, see Activity actions menu in Connector basics.
Google Pub Sub Publish Message activities can be used as a target with these operation patterns:
- Transformation pattern
- Two-transformation pattern (as the first or second target)
To use the activity with scripting functions, write the data to a temporary location and then use that temporary location in the scripting function.
When ready, deploy and run the operation and validate behavior by checking the operation logs.