Fix: text chunking processor ingestion bug on multi-node cluster

[yuye-aws]

Description

For multi node cluster, the text chunking processor would produce "no such index" error if the configured shard number is less than the number of nodes. This is because some node does not contain the shard information. When we get max token count setting, indicesService fails to find the index information.

IndexService indexService = indicesService.indexServiceSafe(indexMetadata.getIndex());

Issues Resolved

Fix ingestion bug on multi-node cluster

Check List

• New functionality includes testing.
  • All tests pass
• New functionality has been documented.
  • New functionality has javadoc added
• Commits are signed as per the DCO using --signoff

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[yuye-aws]

Hi maintainers. This PR is a fix towards text chunking processor. Please attach backport 2.x and backport 2.13 labels to this PR.

[yuye-aws]

This PR is still work in progress. Before getting merged, this PR must satisfy the following conditions :

• All integration test cases get passed with a three node cluster.

[yuye-aws]

@model-collapse @zane-neo This PR is ready for review now. Please merge this PR after passing all the CI workflow.

[chishui]

Shall we add an IT to cover this "configured shard number is less than the number of nodes" scenario? Can be done in a separate issue and PR.

[zhichao-aws]

Shall we add an IT to cover this "configured shard number is less than the number of nodes" scenario? Can be done in a separate issue and PR.

In current CI all IT are run with one node. I think we can enhance the CI framework by adding the build with -PnumNodes=3. This can help us exclude bugs in distributed scenerio at early stage.

[model-collapse]

All concerns addressed.

[vibrantvarun]

We can't merge the PR until bwc tests passes.

[navneet1v]

@model-collapse GH workflows are failing. Lets ensure GH actions are successful before approving the PRs

[vibrantvarun]

Even gradle checks are failing @yuye-aws

[vibrantvarun]

"Model not deployed yet" error coming from ml-commons opensearch-project/ml-commons#2382

[zane-neo]

"Model not deployed yet" error coming from ml-commons opensearch-project/ml-commons#2382

This is another issue that related to ml-commons main branch, we'll track this with a new issue. We'll merge this one for now as it fixes an critical issue that could impact on customers.

[opensearch-trigger-bot]

The backport to 2.13 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-2.13 2.13
# Navigate to the new working tree
cd .worktrees/backport-2.13
# Create a new branch
git switch --create backport/backport-713-to-2.13
# Cherry-pick the merged commit of this pull request and resolve the conflicts
git cherry-pick -x --mainline 1 2d42408c70e01b95825744bea0182ff361090a4e
# Push it to GitHub
git push --set-upstream origin backport/backport-713-to-2.13
# Go back to the original working tree
cd ../..
# Delete the working tree
git worktree remove .worktrees/backport-2.13

Then, create a pull request where the base branch is 2.13 and the compare/head branch is backport/backport-713-to-2.13.