job: add job submission on register

[lgfa29]

Send job submission on register to retain original job source.

Closes #392

[gulducat]

Couple comments regarding diff detection to consider, but overall LGTM!

[gulducat]

To clarify the implication here, considering your recent comment on issue #1 -- This means that if the jobspec HCL is updated via UI or CLI (or appropriately crafted API call) outside of TF, this will pull that down for comparison, so remote HCL changes can be detected that the current jobspecEqual() might otherwise miss.

It does not affect what Nomad considers to be a "change" (as with nomad plan), like if semantically unimportant things (like hcl comments) change, then there still would be no change detected, as is the current state, but if there is some meaningful change, then it may be better detected and compared with this new ability.

Do I have that right?

[lgfa29]

so remote HCL changes can be detected that the current jobspecEqual() might otherwise miss.

Yes, currently jobspecEqual() doesn't even detect any remote changes because, up until now, it didn't have access to the remote jobspec.

if semantically unimportant things (like hcl comments) change, then there still would be no change detected

Right, but that's not because of this change, this is because jobspecEqual() does a semantic comparison, meaning, it parses the raw string and compares the result job object, so changes like comments and formatting are ignored.

terraform-provider-nomad/nomad/resource_job.go

Lines 989 to 1032 in 5afd8e7

	func jobspecEqual(k, old, new string, d ResourceFieldGetter) bool {
	var oldJob *api.Job
	var newJob *api.Job
	var oldErr error
	var newErr error
	// Read job parsing config.
	jobParserConfig, err := parseJobParserConfig(d)
	if err != nil {
	log.Printf("[ERROR] %v", err)
	return false
	}
	switch {
	case jobParserConfig.JSON.Enabled:
	oldJob, oldErr = parseJSONJobspec(old)
	newJob, newErr = parseJSONJobspec(new)
	case jobParserConfig.HCL1.Enabled:
	oldJob, oldErr = jobspec.Parse(strings.NewReader(old))
	newJob, newErr = jobspec.Parse(strings.NewReader(new))
	default:
	oldJob, oldErr = parseHCL2Jobspec(old, jobParserConfig.HCL2)
	newJob, newErr = parseHCL2Jobspec(new, jobParserConfig.HCL2)
	}
	if oldErr != nil {
	log.Println("error parsing old jobspec")
	log.Printf("%v\n", oldJob)
	log.Printf("%v", oldErr)
	return false
	}
	if newErr != nil {
	log.Println("error parsing new jobspec")
	log.Printf("%v\n", newJob)
	log.Printf("%v", newErr)
	return false
	}
	// Init
	oldJob.Canonicalize()
	newJob.Canonicalize()
	// Check for jobspec equality
	return reflect.DeepEqual(oldJob, newJob)
	}

[gulducat]

If I do not have hcl2{} in my TF resource, but I then manually (UI or CLI) update the job with a variable value, TF will see "no changes."

Put differently, only if my nomad_job resource has hcl2{} in it (per this d.GetOk()) will TF state contain anything about variables (per d.Set() below), otherwise remote changes are invisible to TF.

Maybe that's an intended feature? but is a little surprising to me.

[lgfa29]

That's right, but I kind of did that on purpose to avoid changes to state as much as possible. If you're not using HCL2, you probably have a reason for that, so switching to it outside of Terraform means you're doing something funky 😛

But if that's surprising then 070092d forces updates if variables change. Is this better?