check model auto deploy

[Zhangxunmt]

Description

Checking if the model has auto-deploy enabled at the model level. If true, go ahead with auto deploy. Otherwise return 400 illegal_argument_exception with message asking Users to deploy model first.
If the deploy_setting is null in the Model, by default we treat it as true.

PUT /_plugins/_ml/models/qPUJgo4BHjpQDZnR5sw4
{
    "deploy_setting": {"is_auto_deploy_enabled": false}
}
POST /_plugins/_ml/models/qPUJgo4BHjpQDZnR5sw4/_predict {...}
# Response
{
  "error": {
    "root_cause": [
      {
        "type": "illegal_argument_exception",
        "reason": "Model not ready yet. Please run this first: POST /_plugins/_ml/models/qPUJgo4BHjpQDZnR5sw4/_deploy"
      }
    ],
    "type": "illegal_argument_exception",
    "reason": "Model not ready yet. Please run this first: POST /_plugins/_ml/models/qPUJgo4BHjpQDZnR5sw4/_deploy"
  },
  "status": 400
}

PUT /_plugins/_ml/models/qPUJgo4BHjpQDZnR5sw4
{
    "deploy_setting": {"is_auto_deploy_enabled": true}
}
POST /_plugins/_ml/models/qPUJgo4BHjpQDZnR5sw4/_predict {...}
# Response
{
  "inference_results": [
    ......
 ]
}

Issues Resolved

[List any issues this PR will resolve]

Check List

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

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[dhrubo-os]

[nit] We are assuming customer is using dev tools.

May be set a generic message like: "The model is not deployed yet. Please deploy the model first." ?