site-kit-wp: Implement HaTS survey triggers for users who answers "Other" to any User Input question

Feature Description

Since we’re removing the text field next to the “Other” in all the User Input questions in #6181, we should implement surveys for users who answer other to get more information on their choice. This can be a single survey or multiple surveys, whichever is best UX.

Related Asana Task: https://app.asana.com/0/1201538818998708/1203393984679795

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Acceptance criteria

• A survey should be triggered for users who answer “Other” to at least one of the User Input questions.
• This should only be triggered once user completes answering the questions.
  • This should also trigger after user edits user input question and at least one of the answers changes to “Other”.
• For sites with multiple admins, the survey will only appear to the admin who answered the question. This is regardless whether the question is user or site specific.
• Since there are three user input questions and user can answer Other to any combination of them, one of the following trigger IDs should be used based on the answer.
  • userInput_answered_other__purpose
  • userInput_answered_other__postFrequency
  • userInput_answered_other__goals
  • userInput_answered_other__purpose_postFrequency
  • userInput_answered_other__purpose_goals
  • userInput_answered_other__postFrequency_goals
  • userInput_answered_other__purpose_postFrequency_goals
• The the survey returned from the Service will be queued and shown to the user as part of #6306.

Implementation Brief

• Create a new action maybeTriggerUserInputSurvey action in CORE_USER store.
  • Get the current user input settings using the getUserInputSettings selector.
  • If there is at least one submitted answer contains other-
    • Construct one of the survey triggerID mentioned in the AC.
    • Using the triggerSurvey action from CORE_USER trigger the survey for the user using the aforementioned triggerID.
• Update the saveUserInputSettings action of CORE_USER:
  • If there was no error, before setting isSaving to false, yield the maybeTriggerUserInputSurvey action.
• In addition to triggering the survey, we need to also make sure any existing outdated surveys in the Survey_Queue is dequeued. For that:
  • In Google\Site_Kit\Core\User_Input\REST_User_Input_Controller class:
    • Add a protected $survey_queue instance variable which will be received and assigned in the constructor.
    • In POST:core/user/data/user-input-settings rest route:
      • Before returning the return value of rest_ensure_response check if it’s a WP_REST_Response.
      • Dequeue user_input_answered_other_survey survey using the $survey_queue->dequeue( survey_id ).
        • (Note: This is the preliminary survey_id for all userInput “other” surveys )
  • In Google\Site_Kit\Core\User_Input\User_Input class:
    • In the constructor, pass a new Survey_Queue instance while creating the REST_User_Input_Controller class instance.

Test Coverage

• Add tests for maybeTriggerUserInputSurvey action.
• Add test coverage for saveUserInputSettings action.
• Add test coverage for the above PHP changes.

QA Brief

• Set up a new site, install, and connect Site KIt.
• Using the tester plugin, enable the userInput feature flag.
• Go to the /wp-admin/admin.php?page=googlesitekit-user-input screen. Answer the user input questions and answer “Other” for one or more questions.
• In the User Input preview screen, open your browser developer tools and go to the “Network” tab. Ensure that network log recording is on so that network requests persist even though you get navigated to a different screen.
• Click “Save”.
• Ensure that you see a request to the /wp-json/google-site-kit/v1/core/user/data/survey-trigger?_locale=user endpoint that has {"data":{"triggerID":"userInput_answered_other__[TRIGGER_ID]"}} in payload.
• The TRIGGER_ID placeholder above should include slug of questions that you have answered “Other” for, according to the ACs.
• Answer the questions again but do not choose “Other” this time. Verify that the above network request is not made in this case.

Changelog entry

• Implement HaTS survey triggers for users who answers “Other” to any User Input question