Multiple containers don't load

Looks like this starts at the container resolver and then issues propagate out to all the hooks. This likely will require some extensive refactoring.

One use case for multiple containers:

We have a distribution that manages configuration for 1000's of sites, and do not want to override our core distro config just to add an additional container for our clients that have them, because that adds significant service, support and maintenance overhead.

Fair enough use case indeed -- however tests are failing so moving to needs work until that issue can be uncovered.

This patch wont apply to current 2.0.x-dev version. When viewing the MR the page throws an error and comments and MR not viewable. How do we move forward with this?

Please review Patch

The last submitted patch, 9: 3376960-9.patch, failed testing. View results →
- codesniffer_fixes.patch Interdiff of automated coding standards fixes only.

@chaitanyadessai's patch seems to be a reroll of !54, so I applied that locally.

I found that the code did not load multiple gtag script tags correctly. Multiple tags loaded, but each tag repeated the config of the first tag (except for that the tagId). This gave a 404 for those tags.

To resolve this, I took the pattern from google_tag_page_top() and refactored google_tag_page_attachments() accordingly.

gtm.js also needed to account for multiple tag configs, so I also refactored parts of that file.

Since MR !54 was out of date, I took the MR's branch and rebased on 2.0.x., then added my changes and pushed the new branch. I created MR !83. I'm not completely clear if this handles every case, but it should get us closer.

Confirming this is still an issue in 2.0.5. Our use case is similar to trackleft2. We are able to work around this for now as we don't have many instances where we use multiple containers.

Version 2.0.7 with fixes in MR 83 shows multiple <iframe src="https://www.googletagmanager.com/ns.html?id=.... but <script src="https://www.googletagmanager.com/gtm.js?id= disappeared completely.

^^ I rerolled again so the patch will apply. But I noticed, we're failing 3 PHPUnit tests now.

I think we'll also need to update js/gtm.js so that there can be > 1 dataLayer name. Right now, everything is going into dataLayer.

So, more work to be done, but patch works again.

trackleft2 → changed the visibility of the branch 3376960-multiple-containers-dont-2 to hidden.

trackleft2 → changed the visibility of the branch 3376960-multiple-containers-dont-2 to active.

trackleft2 → changed the visibility of the branch 2.0.x to hidden.

trackleft2 → changed the visibility of the branch 3376960-multiple-containers-dont to hidden.

I've updated the merge request !83 to fix an outstanding bug in the patch that has to do with cache tag propagation.
Additionally, I've updated the PHPUnit tests and Issue Summary to account for the API changes present in this MR.

I think that I would suggest releasing this in a major or minor version bump.