Forms: Add backend MailPoet integration

[edanzer]

Fixes FORMS-232

Proposed changes:

Important:

• This is branched from and is the backend counterpart to this PR, which adds MailPoet integration in the editor. By testing this, you can also test that PR in the editor.
• All MailPoet integration remains behind a feature flag which is false by default. See testing instructions.

Changes:

• In class-contact-form-plugin.php, we hook onto the 'grunion_after_feedback_post_inserted' to fire MailPoet integration logic.
  • This is wrapped in our MailPoet feature flag
• Adds a new MailPoet_Integration class to handle MailPoet logic.
  • The main callback is MailPoetIntegration::handle_mailpoet_integration(). This method runs some simple checks for spam and for the connectMailPoet form attribute, and if all is clear, fires MailPoet integration methods, including
  • Instantiating the MailPoet API
  • Creating a Jetpack Form Subscribers list if one does not already exist. The method for this allow allows us to pass in a field name. In a future PR, we should fetch all lists and allow users to select one or add a new list in the block editor in the MailPoet card. I'd like to handle that separately.
  • Extracting subscriber data from the form. Email is the only required field for MailPoet, but we also check for first name and last name. For all fields, we try to find them using both field IDs and field Labels.
  • Finally, adding the contact to the MailPoet list.

Follow ups (not yet done):

• We'll want to tie this into the Consent checkbox field, or create a new one for MailPoet. We'll want to check for consent before adding users to the list, depending on conditions.
• We'll want to fetch all MailPoet lists, and show them in the MailPoet card in the modal. Users will be able to select one, or add a new list.

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

See the linear issue and project above.

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

Yes.

Testing instructions:

• Add a form to a page. Be sure to include at least an "Email" field. You can also try adding "First Name" and "Last Name". Other fields will not be added to MailPoet.
• If needed, install and activate MailPoet from the modal, and get and add a MailPoet key. To get a key, you can create a free account at https://account.mailpoet.com
• When everything active and connected, you'll be able to enable the toggle on the card header, which means your form is now connected to MailPoet. You'll see the MailPoet icon on the sidebar.
• Go to the frontend and submit your form.
• Go to MailPoet -> Lists and confirm the "Jetpack Form Subscribers" list is added.
• Go to MailPoet -> Subscribers and confirm a contact has been added using the email you added to the form.
• Disable MailPoet connection in the modal, resave, resubmit the form, and confirm that the email/contact is not added to MailPoet.

[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 WoA dev 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 (Jetpack), and enable the add/forms-backend-mailpoet-integration branch.
• To test on Simple, run the following command on your sandbox:

bin/jetpack-downloader test jetpack add/forms-backend-mailpoet-integration

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]

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[jp-launch-control]

Code Coverage Summary

Coverage changed in 3 files.

File	Coverage	Δ%	Δ Uncovered
projects/packages/forms/src/contact-form/class-contact-form-plugin.php	435/1177 (36.96%)	-0.14%	6 💔
projects/packages/forms/src/contact-form/class-contact-form.php	622/1140 (54.56%)	0.04%	0 💚
projects/packages/forms/src/class-jetpack-forms.php	8/21 (38.10%)	4.76%	-1 💚

1 file is newly checked for coverage.

File	Coverage
projects/packages/forms/src/service/class-mailpoet-integration.php	0/69 (0.00%) 💔

Full summary · PHP report · JS report

_{If appropriate, add one of these labels to override the failing coverage check: Covered by non-unit tests Use to ignore the Code coverage requirement check when E2Es or other non-unit tests cover the code Coverage tests to be added later Use to ignore the Code coverage requirement check when tests will be added in a follow-up PR I don't care about code coverage for this PR Use this label to ignore the check for insufficient code coveage.}

[dhasilva]

LGTM, works as described

[enejb]

It would be good to wait for #44121 to land since then we could make sure that you can work the the fields easier.

The base branch was changed.

[edanzer]

Update: I hadn't wrapped the hook for the MailPoet logic in the feature flag. This has now been added. So if feature flag is off, no backend MailPoet logic will run (except that connectMailPoet will be added as a new default attribute).