Collecting Data requests fail when both Analytics and Ads modules are connected

[benbowler]

Bug Description

When First-party mode is enabled and both the Analytics and Ads modules are connected, network requests for collecting measurement data fail. This results in 404 errors and console warnings in the browser. The issue does not occur when only the Analytics module or only the Ads module is connected.

Screenshots

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When loading a page with FPM enabled, there are 2x 404 console errors related to tracking. It appears as though the value of FPS_PATH constant (which is PHP_FPM_REPLACE_PATH by default) is not being replaced in certain cases, here are the GET and POST endpoints in question:

https://simon-d-fpm-bug-bash.instawp.xyz/PHP_FPM_REPLACE_PATH/g/ccm/collect?en=page_view&dr=simon-d-fpm-bug-bash.instawp.xyz&dl=https%3A%2F%2Fsimon-d-fpm-bug-bash.instawp.xyz%2F&scrsrc=simon-d-fpm-bug-bash.instawp.xyz&frm=0&rnd=881594217.1734338296&dt=heavenly-goosander-92e4c9.instawp.xyz&auid=785249758.1734337691&navt=r&npa=0&did=dZTNiMT&gdid=dZTNiMT&gtm=45892e4cc1za204zb9136159890&gcd=13l3l3l3l1l1&dma=0&tag_exp=101925629~102067555~102067808~102081485~102198178&tft=1734338295774&tfd=6041&apve=1

https://simon-d-fpm-bug-bash.instawp.xyz/PHP_FPM_REPLACE_PATH/pagead/viewthroughconversion/12345/?random=1734338295771&cv=11&fst=1734338295771&bg=ffffff&guid=ON&async=1&gtm=45892e4cc1za204zb9136159890&gcd=13l3l3l3l1l1&dma=0&tag_exp=101925629~102067555~102067808~102081485~102198178&u_w=1512&u_h=982&url=https%3A%2F%2Fsimon-d-fpm-bug-bash.instawp.xyz%2F&ref=https%3A%2F%2Fsimon-d-fpm-bug-bash.instawp.xyz%2Fwp-admin%2Fadmin.php%3Fpage%3Dgooglesitekit-dashboard&hn=www.googleadservices.com&frm=0&tiba=heavenly-goosander-92e4c9.instawp.xyz&did=dZTNiMT&gdid=dZTNiMT&npa=0&auid=785249758.1734337691&uaa=arm&uab=64&uafvl=Google%2520Chrome%3B131.0.6778.140%7CChromium%3B131.0.6778.140%7CNot_A%2520Brand%3B24.0.0.0&uamb=0&uam=&uap=macOS&uapv=13.0.0&uaw=0&fledge=1&data=event%3Dgtag.config&rfmt=3&fmt=4

See the related Asana task.

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Acceptance criteria

• Once the issue with the FPS_PATH constant (PHP_FPM_REPLACE_PATH) replacement is resolved by the Google team, the measurement.php script in Site Kit should be updated to the latest version.
• When First-party mode is enabled and both Analytics and Ads modules are connected:
  • Network requests for collecting measurement data should not fail.
  • There should be no 404 errors or console warnings in the browser.

Note: This issue originates from the proxy script and is not a bug in Site Kit itself. The resolution will involve updating the measurement.php script to the latest version once the fix is provided by the Google team.

Implementation Brief

• Retrieve the latest version of the measurement.php script with the fix mentioned in the AC.
• Replace the script at {plugin root}/fpm/measurement.php
  • Port the health check code from the current version of the script, which returns ok when the healthCheck query parameter is provided.
  • Make sure to retain the modification notice in the file header.
  • Update the @version tag in the code comment to the git hash of the new version of the measurement.php file.

Test Coverage

• No additional test coverage required.

QA Brief

Changelog entry

[hussain-t]

@benbowler, this issue is identical to #9903. We can close that one and consolidate the details here for clarity.

[techanvil]

AC ✅

[techanvil]

Thanks @benbowler, the IB LGTM. It was missing an estimate so I've added one, a 7.

IB ✅