Allow method parameter override for training based indices (solves issue #2246)

[buddharajusahil]

Description

#2246

From mode/disk-based feature, we introduced concept of mode and compression level that will dynamically set default resolution. For indices created directly from the method (i.e. mapping) we allow users to override parameters if they want.

However, for training, we added the mode and compression, but made them mutually exclusive with method. See: https://github.com/opensearch-project/k-NN/blob/main/src/main/java/org/opensearch/knn/plugin/rest/RestTrainModelHandler.java#L138-L139. We need to remove this and allow method overriding to provide a consistent ux experience across the plugin.

Related Issues

Resolves #2246

Check List

• New functionality includes testing.
• New functionality has been documented.
• [N/A] API changes companion pull request created.
• Commits are signed per the DCO using --signoff.
• Public documentation issue/PR created.

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[navneet1v]

@owenhalpert can you please fix the changelog.

[heemin32]

Do we know why this was previously blocked, considering it only involves removing two lines of code?

[buddharajusahil]

Do we know why this was previously blocked, considering it only involves removing two lines of code?

Hi @heemin32,

So Jack said that these checks were added in this pr #2034 and not removed before the release. Then it got removed in this pr #2083 but training was missed

[jmazanec15]

@buddharajusahil Can you run ./gradlew :spotlessApply to fix style?

[jmazanec15]

LGTM - we just need to fix CI

[jmazanec15]

LGTM - thanks

[opensearch-trigger-bot]

The backport to 2.x failed:

The process '/usr/bin/git' failed with exit code 1

To backport manually, run these commands in your terminal:

# Fetch latest updates from GitHub
git fetch
# Create a new working tree
git worktree add .worktrees/backport-2.x 2.x
# Navigate to the new working tree
cd .worktrees/backport-2.x
# Create a new branch
git switch --create backport/backport-2290-to-2.x
# Cherry-pick the merged commit of this pull request and resolve the conflicts
git cherry-pick -x --mainline 1 19f045d763cd7f302c2b96c8731b725484b14bec
# Push it to GitHub
git push --set-upstream origin backport/backport-2290-to-2.x
# Go back to the original working tree
cd ../..
# Delete the working tree
git worktree remove .worktrees/backport-2.x

Then, create a pull request where the base branch is 2.x and the compare/head branch is backport/backport-2290-to-2.x.

[naveentatikonda]

@buddharajusahil can you fix the conflicts and create a backport PR to 2.x ?