Remove Default master encryption key from settings.

[vmmusings]

Description

• plugins.query.datasources.encryption.masterkey is being used for encrypting auth information in datasource metadata configuration. In previous versions, this config will default to 0000000000000000 if not provided.
• However, we have decided to remove the logic of defaulting for better security posture. So with this change, User has to generate a master key and configure in the opensearch.yml for using datasource CRUD APIs.
• Updated documentation: https://github.com/vamsi-amazon/sql/blob/remove-default-master-key/docs/user/ppl/admin/datasources.rst#master-key-config-for-encrypting-credential-information

Testing

Request:

{
  "name": "aws_prometheus3",
  "connector": "PROMETHEUS",
  "allowedRoles": [],
  "properties": {
    "prometheus.uri": "https://localhost:9090",
    "prometheus.auth.type" : "basicauth",
    "prometheus.auth.username" : "username",
    "prometheus.auth.password" : "password"
  }
}

Response

{
  "status": 400,
  "error": {
    "type": "IllegalStateException",
    "reason": "Invalid Request",
    "details": "Master key is a required config for using datasource APIs. Please set the following config in opensearch.yml in all the cluster nodes. More details can be found here: https://github.com/opensearch-project/sql/blob/main/docs/user/ppl/admin/datasources.rst#master-key-config-for-encrypting-credential-information"
  }
}

Issues Resolved

[List any issues this PR will resolve]

Check List

• New functionality includes testing.
  • All tests pass, including unit test, integration test and doctest
• New functionality has been documented.
  • New functionality has javadoc added
  • New functionality has user manual doc added
• Commits are signed per the DCO using --signoff

By submitting this pull request, I confirm that my contribution is made under the terms of the Apache 2.0 license.
For more information on following Developer Certificate of Origin and signing off your commits, please check here.

[codecov]

Codecov Report

Merging #1851 (42f4ed3) into main (f5031a7) will increase coverage by 0.00%.
The diff coverage is 100.00%.

@@            Coverage Diff            @@
##               main    #1851   +/-   ##
=========================================
  Coverage     97.39%   97.39%           
- Complexity     4600     4602    +2     
=========================================
  Files           401      401           
  Lines         11381    11386    +5     
  Branches        843      843           
=========================================
+ Hits          11084    11089    +5     
  Misses          290      290           
  Partials          7        7           

Flag	Coverage Δ
sql-engine	97.39% <100.00%> (+<0.01%)	⬆️

Flags with carried forward coverage won't be shown. Click here to find out more.

Impacted Files	Coverage Δ
...ql/datasources/rest/RestDataSourceQueryAction.java	0.00% <ø> (ø)
...rch/sql/opensearch/setting/OpenSearchSettings.java	100.00% <ø> (ø)
...earch/sql/datasources/encryptor/EncryptorImpl.java	100.00% <100.00%> (ø)