Newsletter Widget: Render placeholder from Calypso app behind a constant

[spsiddarthan]

This PR renders a placeholder for the Newsletter widget. This happens by rendering the stadnalone app built in Calypso - Automattic/wp-calypso#99652.

This PR also adds feature checks on Jetpack, Simple and Atomic.

Proposed changes:

• Load the standalone app in Jetpack/WPCOM/Atomic.

Other information:

• Have you written new tests for your changes, if applicable?
• Have you checked the E2E test CI results, and verified that your changes do not break them?
• Have you tested your changes on WordPress.com, if applicable (if so, you'll see a generated comment below with a script to run)?

Jetpack product discussion

Does this pull request change what data or activity we track or use?

No

Testing instructions:

Jetpack/WOA sites.

• Add the constant define( 'JETPACK_NEWSLETTER_WIDGET', true ); to your wp-config.php file if you're testing this on local.
  For WOA sites, this constant can be set in the wp-config file which lives in a file like this home/150782295/htdocs/wp-config.php, essentially in your htdocs folder.

Similarly for JN sites, you can do this in /srv/htdocs. Your JN site's wp-admin has the ssh creds you will need to update the wp-config.php file to set the JETPACK_NEWSLETTER_WIDGET constant.

• Sandbox widget.wp.com and public-api

x.x.x.x public-api.wordpress.com
x.x.x.x widgets.wp.com

x.x.x.x is your sandbox's IP as usual.

• Follow the instructions in Newsletter: Add standalone app. wp-calypso#99652 to prepare the standalone app's build.
• Go to wp-admin and ensure that you see the newsletter widget.
• Remove the constant JETPACK_NEWSLETTER_WIDGET or ensure that it's set to false so you we be sure that the feature check is working.

Simple sites

• Follow the steps in this comment to prepare your sandbox.
• Follow the instructions in Newsletter: Add standalone app. wp-calypso#99652 to prepare the standalone app's build. Ignore if already done.
• In your 0-sandbox.php, Add the constant define( 'JETPACK_NEWSLETTER_WIDGET', true );
• Sandbox your simple site as well along with public-api.wordpress.com and widgets.wp.com
• Go to the site's wp-admin and see that the newsletter widget loads.
• Remove the constant to ensure that the newsletter widget disappears.

[github-actions]

Are you an Automattician? Please test your changes on all WordPress.com environments to help mitigate accidental explosions.

• To test on WoA, go to the Plugins menu on a WordPress.com Simple site. Click on the "Upload" button and follow the upgrade flow to be able to upload, install, and activate the Jetpack Beta plugin. Once the plugin is active, go to Jetpack > Jetpack Beta, select your plugin, and enable the add/widget-newsletter branch.

  • For jetpack-mu-wpcom changes, also add define( 'JETPACK_MU_WPCOM_LOAD_VIA_BETA_PLUGIN', true ); to your wp-config.php file.

• To test on Simple, run the following command on your sandbox:

  bin/jetpack-downloader test jetpack add/widget-newsletter
  

  bin/jetpack-downloader test jetpack-mu-wpcom-plugin add/widget-newsletter
  

Interested in more tips and information?

• In your local development environment, use the jetpack rsync command to sync your changes to a WoA dev blog.
• Read more about our development workflow here: PCYsg-eg0-p2
• Figure out when your changes will be shipped to customers here: PCYsg-eg5-p2

[github-actions]

Thank you for your PR!

When contributing to Jetpack, we have a few suggestions that can help us test and review your patch:

• ✅ Include a description of your PR changes.
  
• ✅ Add a "[Status]" label (In Progress, Needs Team Review, ...).
  
• 🔴 Add a "[Type]" label (Bug, Enhancement, Janitorial, Task).
  
• ✅ Add testing instructions.
  
• ✅ Specify whether this PR includes any changes to data or privacy.
  
• ✅ Add changelog entries to affected projects
  

This comment will be updated as you work on your PR and make changes. If you think that some of those checks are not needed for your PR, please explain why you think so. Thanks for cooperation 🤖

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The e2e test report can be found here. Please note that it can take a few minutes after the e2e tests checks are complete for the report to be available.

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Follow this PR Review Process:

1. Ensure all required checks appearing at the bottom of this PR are passing.
2. Choose a review path based on your changes:
   • A. Team Review: add the "[Status] Needs Team Review" label
     • For most changes, including minor cross-team impacts.
     • Example: Updating a team-specific component or a small change to a shared library.
   • B. Crew Review: add the "[Status] Needs Review" label
     • For significant changes to core functionality.
     • Example: Major updates to a shared library or complex features.
   • C. Both: Start with Team, then request Crew
     • For complex changes or when you need extra confidence.
     • Example: Refactor affecting multiple systems.
3. Get at least one approval before merging.

Still unsure? Reach out in #jetpack-developers for guidance!

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Jetpack plugin:

The Jetpack plugin has different release cadences depending on the platform:

• WordPress.com Simple releases happen semi-continuously (PCYsg-Jjm-p2).
• WoA releases happen weekly.
• Releases to self-hosted sites happen monthly. The next release is scheduled for none scheduled (scheduled code freeze on undefined).

If you have any questions about the release process, please ask in the #jetpack-releases channel on Slack.

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Mu Wpcom plugin:

• Next scheduled release: WordPress.com Simple releases happen semi-continuously (PCYsg-Jjm-p2).

If you have any questions about the release process, please ask in the #jetpack-releases channel on Slack.

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Wpcomsh plugin:

• Next scheduled release: Atomic deploys happen twice daily on weekdays (p9o2xV-2EN-p2).

If you have any questions about the release process, please ask in the #jetpack-releases channel on Slack.

[jp-launch-control]

Code Coverage Summary

Coverage changed in 2 files.

File	Coverage	Δ%	Δ Uncovered
projects/packages/jetpack-mu-wpcom/src/class-jetpack-mu-wpcom.php	0/218 (0.00%)	0.00%	3 ❤️‍🩹
projects/plugins/jetpack/class.jetpack.php	718/2374 (30.24%)	-0.04%	3 ❤️‍🩹

1 file is newly checked for coverage.

File	Coverage
projects/packages/jetpack-mu-wpcom/src/features/wpcom-newsletter-widget/wpcom-newsletter-widget.php	0/3 (0.00%) 💔

Full summary · PHP report · JS report

_{Add label I don't care about code coverage for this PR Use this label to ignore the check for insufficient code coveage. to override the failing coverage check.}

[spsiddarthan]

config_data is currently empty, we can add what we want based on other widgets like Jetpack stats when we begin working on adding the functionality for the newsletter widget.