(dev/core#5464) Iframe - Add support for hosting Civi IFRAMEs on WordPress

[totten]

Overview

See https://lab.civicrm.org/dev/core/-/issues/5464

Before

If you enable the extension iframe, then it complains about the lack of a template.

After

In combination with other patches for civicrm-wordpress.git (civicrm/civicrm-wordpress#336), it should be able to handle IFRAMEs on WordPress without needing to deploy a dedicated iframe.php connector.

To indicate that a URL should be rendered in the fashion of an iframe, append ?_cvwpif=1.

Technical Details

When making an <IFRAME SRC="..."> tag, this uses /index.php?...&_cvwpif=1 instead of using /iframe.php. This indicates that the request is supposed to be handled in the style of an IFRAME (stripping out CMS navigation; disregarding any pre-existing sessions within the iframe).

I've done some initial testing using a cross-domain IFRAME:

• Workflow: Register for a free event (civicrm/event/register)
• Provider Site: CiviCRM@master with [email protected]
• Consumer Site: Raw HTML site (on separate domain-name)
• Browsers: Firefox (macOS) and Safari (macOS)

We'll see what Jenkins has to say. It should be safe to merge the PRs for civicrm-core and civicrm-wordpress in any order, though it generally makes to merge them at about the same time.

[civibot]

🤖 Thank you for contributing to CiviCRM! ❤️ We will need to test and review this PR. 👷

Introduction for new contributors...

• If this is your first PR, an admin will greenlight automated testing with the command ok to test or add to whitelist.
• A series of tests will automatically run. You can see the results at the bottom of this page (if there are any problems, it will include a link to see what went wrong).
• A demo site will be built where anyone can try out a version of CiviCRM that includes your changes.
• If this process needs to be repeated, an admin will issue the command test this please to rerun tests and build a new demo site.
• Before this PR can be merged, it needs to be reviewed. Please keep in mind that reviewers are volunteers, and their response time can vary from a few hours to a few weeks depending on their availability and their knowledge of this particular part of CiviCRM.
• A great way to speed up this process is to "trade reviews" with someone - find an open PR that you feel able to review, and leave a comment like "I'm reviewing this now, could you please review mine?" (include a link to yours). You don't have to wait for a response to get started (and you don't have to stop at one!) the more you review, the faster this process goes for everyone 😄
• To ensure that you are credited properly in the final release notes, please add yourself to contributor-key.yml
• For more information about contributing, see CONTRIBUTING.md.

Quick links for reviewers...

• ➡️ PR Demo site (can be rebuilt with the command test this please).
• 📖 Review standards
• 🗒️ Review template (brief or verbose)

➡️ Online demo of this PR 🔗