Currently p2 update sites are only partially mirrored so it's not possible for the Eclipse Installer or a IDE update to find the missing artifacts.
What is the expected correct behavior?
A p2 update site mirror should be complete.
Please do not use exclusion patterns that can match files (rather than folders) and most especially not ones that can files that can occur in p2 update sites.
This needs to be fixed well in advance of next week's release...
Designs
Child items
...
Show closed items
Linked items
0
Link issues together to show that they're related or that one is blocking others.
Learn more.
*.php*.* is definitely too aggressive. It matches 11000 files. I'm not sure which files it was intended to exclude (*.php.*.html files?).
*stable* is too wide as well, as it matches file names that contain the word "persistable" for example. It also matches folder names where it's ambiguous if the content should be mirrored.
Now that I'm home on my fast internet I could test installing the Eclipse Eierlegende Wollmilchsau in a fresh "user home" to install effectively all of the plugins and features of the release train. Unfortunately that reveals yet more missing artifacts:
It really depends on what the mirrorURL is set to.
If the repo is:
/jubula/release/indigo/R3/
And mirrorURL is:
/jubula/release/
Then file /jubula/release/indigo/R3/plugins/org.eclipse.jubula.client.ui_1.1.0.201109140653.jar
will be incorrectly fetched from mirrors that have /jubula/release/
If mirrorURL is /jubula/release/indigo/R3 then the entire repo at /jubula/release/indigo/R3/ will have an empty set, which is also correct.
When accessing a update site such as https://download.eclipse.org/releases/2021-12/202112081000 p2 will use a query exactly like https://www.eclipse.org/downloads/download.php?format=xml&file=/releases/2021-12/202112081000&countryCode=us&timeZone=1&format=xml to determine if there are mirrors for that site. So it's a black or white decision. Either the entire folder is mirrored and all artifacts in the subfolders are expected to be present or there are no mirrors for the folder and then no mirrors are used. In other words, the mirror URL used by p2 is generally exactly the folder of the site itself, and not some parent folder so I don't believe that *indigo*/* would cause any problems.
This is why I suggested that as long as the exclusion patterns exclude an entire folder (though of course not the plugin/feature/binary folders of an update site), then it should not cause problems of "partial mirrors", i.e., mirrors with a subset of artifacts missing...