manifest_diff showing diff where top-level app fields incorrectly are being compared to web process-level fields

[elenasharma]

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Issue

The manifest_diff endpoint shows an incorrect diff when top-level application fields conflict with web process fields.

Context

When I create a manifest diff with a manifest like the following:

---
applications:
- name: test-app
  memory: 1024M
  processes:
  - type: web
    instances: 2
    memory: '256M'

I get an incorrect diff result:

{
   "diff": [
      {
         "op": "replace",
         "path": "/applications/0/memory",
         "was": "256M",
         "value": "1024M"
      }
   ]
}

The resulting diff has the top-level application memory value of "1024M" replacing the web process' memory value of "256M", even though the process memory has not been replaced.

Steps to Reproduce

1. Push an application with a manifest in which there's a top-level application field (e.g. memory) that is the same as a web process field.
2. Without altering the manifest file, use the space guid of the space that the above app is in to create a manifest diff e.g. cf curl /v3/spaces/<SPACE_GUID>/manifest_diff -X POST -H "Content-Type: application/x-yaml" -d @<PATH_TO_MANIFEST_FILE>
3. Observe that in the resulting diff, the web process value appears to be replaced by the top-level application value.

Expected result

I would expect to see no diff, e.g.

{
   "diff": []
}

Current result

The current result is a diff with a "replace":

{
   "diff": [
      {
         "op": "replace",
         "path": "/applications/<PROCESS_INDEX>/<FIELD>",
         "was": "<PROCESS_VALUE>",
         "value": "<TOP_LEVEL_APPLICATION_VALUE"
      }
   ]
}

[sweinstein22]

After further discussion we've decided to ignore top-level memory and disk-quota keys, as they're not part of the supported, documented v3 manifest schema. Those keys will still have an impact when applying manifests or pushing applications in order to preserve backwards compatibility, however they will be ignored in visual app manifest diffs (the GET /v3/apps/:guid/manifest endpoint)

[bepotts]

This issue has been addressed and merged into main. The merge can be viewed here.

[sethboyles]

closing as this was fixed a while ago