[Compute] Inconsistency while using ResourceName.of() helpers

[dtretyakov]

• google-cloud-java version: 0.79-alpha

Steps to reproduce

The recent changes linked to #3604 have caused that Compute SDK usage has become more complicated. Let take a look on the following examples.

Code snippet

Before:

val machineType = ProjectZoneMachineTypeName.of(machineType, myProjectId, zone).toString()
val instance = Instance.newBuilder().setMachineType(machineType).build()
instanceClient.insertInstance(instance)

After #3604 ResourceName.toString() methods does not append projects/ prefix anymore and as result the previous code fragment fails with exceptions like that because they're required by REST APIs:

Caused by: com.google.api.client.http.HttpResponseException: 400 Bad Request
{
 "error": {
  "errors": [
   {
    "domain": "global",
    "reason": "invalid",
    "message": "Invalid value for field 'resource.machineType': 'project-123/zones/europe-west3-b/machineTypes/n1-standard-1'. The URL is malformed."
   },
   {
    "domain": "global",
    "reason": "invalid",
    "message": "Invalid value for field 'resource.disks[0].initializeParams.sourceImage': 'project-123/global/images/image-name'. The URL is malformed."
   }
  ],
  "code": 400,
  "message": "Invalid value for field 'resource.machineType': 'project-123/zones/europe-west3-b/machineTypes/n1-standard-1'. The URL is malformed."
 }
}

To resolve it for each ResourceName should be added ResourceName.SERVICE_ADDRESS prefix like that:

val machineType = ProjectZoneMachineTypeName.SERVICE_ADDRESS + 
    ProjectZoneMachineTypeName.of(machineType, myProjectId, zone).toString()
val instance = Instance.newBuilder().setMachineType(machineType).build()
instanceClient.insertInstance(instance)

[dtretyakov]

//cc @andreamlin, @ajaaym

[andreamlin]

Thanks for filing this issue @dtretyakov .
Looking at it.

[andreamlin]

Repro'd.
@dtretyakov also thanks for the proposed fix! I'll put that into the code generator.

[andreamlin]

Fix should be available in the next release.