lemminx-maven completely ignore local settings

[glhez]

Hello,

I am using version 1.17.0.20201203-1258 (as told by the Window > Help for POM Editor using LemMinX language server / org.eclipse.m2e.lemminx.feature.feature.group).

Because I override the default .m2 local repository and put a file instead (eg: echo "FILE" >"${USERPROFILE}/.m2/repository"), Lemminx Maven is failing because it uses the default repository which I don't want:

Non-resolvable import POM: Could not transfer artifact org.junit:junit-bom:pom:5.7.0 from/to central-mirror (https://jcenter.bintray.com/): %USERPROFILE%\.m2\repository\org\junit\junit-bom\5.7.0\aether-738fca6a-b95a-43a5-90dc-8ccff46afeb0-junit-bom-5.7.0.pom-in-progress (Le chemin d’accès spécifié est introuvable)

To ensure that no one tries to write in %USERPROFILE%\.m2\repository, I created a file instead of a directory - hence the error.

The problem however is that Lemminx don't take into account the default settings.xml which starts with:

<?xml version="1.0" encoding="utf-8" ?>
<settings xmlns="http://maven.apache.org/SETTINGS/1.1.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://maven.apache.org/SETTINGS/1.1.0
                      http://maven.apache.org/xsd/settings-1.1.0.xsd">
  <localRepository>E:\apps\data\maven-local</localRepository>
   ...
</settings>

The settings are configured to default in the Eclipse Maven preferences and I've got a lot of dubious warnings:

Plugin could not be resolved. Ensure the plugin's groupId, artifactId and version are present.

Additional information: Plugin org.apache.maven.plugins:maven-clean-plugin:3.1.0 or one of its dependencies could not be resolved: Failed to read artifact descriptor for org.apache.maven.plugins:maven-clean-plugin:jar:3.1.0

I think those are related: the Language Server is explicitly ignoring the settings.xml for whatever reason.

The issue #42 was closed without much fixes.

A m2.conf as stated in the #42 could be fine, but I don't see why I would have to do that : my settings is in the default location, and it is not even being read otherwise it would have read the repo path...

Is there a way for me to force it to use the good settings/localRepository ?

How can I diagnose ? (the Language Server logs does not seems to provide hints)

[mickaelistria]

I added some bug to debug such cases to https://github.com/eclipse-m2e/m2e-core/blob/master/org.eclipse.m2e.editor.lemminx/HOWTO-DEV.md#how-can-i-debug-the-lemminx-maven-instance-and-m2e-at-the-same-time . Please try that. The piece of code you'd like to place your breakpoint is MavenLemminxExtension#initMavenRequest.

[glhez]

I like the sentence "I added some bug to debug" :)

Some remarks (I may do a PR to update the HOWTO-DEV.md later if needed):

1. my default Eclipse installation did not have the Run as Eclipse installation. I had to use a RCP Eclipse.
2. I fail to understand how to run debug mode. I've put -Dorg.eclipse.wildwebdeveloper.xml.internal.debugPort=20132 to the Java "VM Args", and as well as the Program arg, under as in -vmargs -Dorg.eclipse.wildwebdeveloper.xml.internal.debugPort=20132. Neither worked.
3. How can I tell which Lemminx Maven version I'm under? As far as I understand, the tag reference a version 0.2.0 and from the date, I know I should have it if it was integrated into Eclipse 2020.12. I looked in the Plugins but could not find the version.

Since I could not start in debug mode, I could not check the problem.

In the JSON exchange between server and Eclipse, I can see:

Non-resolvable import POM: Could not transfer artifact org.junit:junit-bom:pom:5.7.0 from/to central-mirror (INTERNAL_REPOSITORY): %USERPROFILE%.m2\repository\org\junit\junit-bom\5.7.0\aether-024b5162-ebbb-462f-ba99-89af31b6d1f0-junit-bom-5.7.0.pom-in-progress (The system cannot find the path specified)
Non-resolvable import POM: Could not transfer artifact com.fasterxml.jackson:jackson-bom:pom:2.12.1 from/to central-mirror (INTERNAL_REPOSITORY): %USERPROFILE%.m2\repository\com\fasterxml\jackson\jackson-bom\2.12.1\aether-b2ca945d-f74a-453c-9b63-6d7897a94c75-jackson-bom-2.12.1.pom-in-progress (The system cannot find the path specified)

This, then, give a lot of error due to missing version - which is probably due to the bom not being available.

I also looked at another pom, which does not a reference a dependency under a bom: no problem there. I suppose there is something done only in case of bom, which trigger the download.

Without debug information, is there a way to produce debug stacktrace as in mvn -e ?

[mickaelistria]

I've put -Dorg.eclipse.wildwebdeveloper.xml.internal.debugPort=20132 to the Java "VM Args", and as well as the Program arg, under as in -vmargs -Dorg.eclipse.wildwebdeveloper.xml.internal.debugPort=20132. Neither worked.

My bad, the property is org.eclipse.wildwebdeveloper.xml.internal.XMLLanguageServer.debugPort. I'll update the doc accordingly.
I also added some extra hints in the HOWTO-DEV.md doc according to your feedback.

[glhez]

Thanks.

The method you mentioned is the good one, however, you can't debug it without resorting to tricks: it is called before the debugger session start (if I close all pom.xml, then the LanguageServer close, ... and well, you can't debug something that is closed). This could be a good idea to also a property to suspend the vm (I've found the commit eclipse-wildwebdeveloper/wildwebdeveloper@0a5abb2#diff-4456e8cd4d3f9f5efa224593afe476fd9ea7c4e4d1281fcdd3f53f7f922fff10 )

The best is to put a breakpoint here: org.eclipse.lemminx.extensions.maven.MavenDiagnosticParticipant.doDiagnostics

And when it goes into project cache, to remove (using Eclipse) the mavenSession so that it reinitialize again (see trace below):

• MavenLemminxExtension.initMavenRequest(PlexusContainer, JsonObject) line: 189
• MavenLemminxExtension.initialize() line: 132
• MavenLemminxExtension.getProjectCache() line: 283
• MavenDiagnosticParticipant.doDiagnostics(DOMDocument, List, XMLValidationSettings, CancelChecker) line: 49

Then I can see what's the problem.

In fact, the maven settings is read from the configured path: https://github.com/eclipse/lemminx-maven/blob/master/lemminx-maven/src/main/java/org/eclipse/lemminx/extensions/maven/MavenLemminxExtension.java#L178

... but the local repository is forced to a default value in line 184 : https://github.com/eclipse/lemminx-maven/blob/master/lemminx-maven/src/main/java/org/eclipse/lemminx/extensions/maven/MavenLemminxExtension.java#L184

This can be seen by putting a breakpoint on that line, and going into setLocalRepositoryPath: the actual path is the expected one! If I force the parameter localRepositoryPath to the this.localRepositoryPath (eg: so that the setter does nothing), my pom.xml is no longer plagued with errors.

As I don't understand the login behind the line 185 to 196, I can only tell that the value should be set only if there is none already set: the settings is always read (once) in any case. I suppose the repo.maven.local is a maven option to override the one defined in settings, and that Lemmix Maven is simply handling it..

I also don't know how this behave if I change the settings.xml after the "project cache" is set.

I'll try to do a PR if I have time this week: I'll use a NTFS Junction from .m2/repository to my actual repository in the mean time.
And strangely enough, I did not have that problem on another computer, so my analysis may only partially apply.

[mickaelistria]

Thanks a lot for the detailed analysis!
The line that sets M2 repo to default should skipped if the settings already configured the local repo.
L185-L196 are meant to allow consumer to override the location of the Maven repo in different ways: if the LS is started with -Dmaven.repo.local=... VM option, or if the initializationOptions (typically provided by the IDE) do configure the local repository. Those are supposed to override the user settings; however, as you realized, the default value shouldn't override the user settings and it currently does, causing this bug.
I'll eagerly review your PR. We plan a release of LemMinX-Maven soon, I hope it will fit in!

[glhez]

Here the PR. Quite simple but in all honestly, I only have the problem at work, on a citrix desktop.

Either the "aether-b2ca945d-f74a-453c-9b63-6d7897a94c75-jackson-bom-2.12.1.pom-in-progress" is not downloaded on my computer, either there is something else.

I do think, all thing considered, that it is an error to force the localRepoPath to some default when you already read the settings and those override the default value.

[mickaelistria]

I do think, all thing considered, that it is an error to force the localRepoPath to some default when you already read the settings and those override the default value.

Yes it is.