fix(storage-browser): listCallerAccessGrantsDeserializer not parsing multiple AccessGrant instances

[ashwinkumar6]

Description of changes

• The listCallerAccessGrantsDeserializer does not handle parsing multiple AccessGrantsInstance.
• When the XML response from service contains a single AccessGrantsInstance items it's parsed into an object; while it's parsed into an array if there are multiple items

Output log before fix
xml parsed

// 1 item
{
  "CallerAccessGrantsList": {
    "AccessGrantsInstance": {
      "ApplicationArn": "ALL",
      "Permission": "READWRITE",
      "GrantScope": "s3://ashwin-portcullis-test1/*"
    }
  }
}

// 2 items
{
  "CallerAccessGrantsList": {
    "AccessGrantsInstance": [
      {
        "ApplicationArn": "ALL",
        "Permission": "READWRITE",
        "GrantScope": "s3://ashwin-portcullis-test1/*"
      },
      {
        "ApplicationArn": "ALL",
        "Permission": "READWRITE",
        "GrantScope": "s3://ashwin-portcullis-test2/*"
      }
    ]
  }
}

Deserializer output

// 1 item
{
  "CallerAccessGrantsList": [
    {
      "ApplicationArn": "ALL",
      "GrantScope": "s3://ashwin-portcullis-test1/*",
      "Permission": "READWRITE"
    }
  ]
}
// 2 items
{
  "CallerAccessGrantsList": [
    {} ====> ERROR
  ]
}

Issue #, if available

Description of how you validated changes

• Updated unit tests
• linked lib and tested locally with AG setup in backend

Checklist

• PR description included
• yarn test passes
• Unit Tests are changed or added
• Relevant documentation is changed or added (and PR referenced)

Checklist for repo maintainers

• Verify E2E tests for existing workflows are working as expected or add E2E tests for newly added workflows
• New source file paths included in this PR have been added to CODEOWNERS, if appropriate

By submitting this pull request, I confirm that my contribution is made under the terms of the Apache 2.0 license.

[HuiSF]

nit: don't we also need to test and verify the case of single AccessGrantsInstance?

[calebpollman]

This is a good callout, can we add an additional test case please?

[ashwinkumar6]

Thx updated,

Considering the fact that the default behavior of xml -> obj parsing is

• single item = object
• multiple items = array of object

The underlying parseXmlBody util is used across all storage APIs. Should we add tests for 'single and multiple xml items' test in other places as well (example ListObjectV2 only has multiple items)
(probably in another PR if required)

[calebpollman]

🚢