cli: add option to return original HCL in job inspect command (#23699)

In 1.6.0 we shipped the ability to review the original HCL in the web UI, but
didn't follow-up with an equivalent in the command line. Add a `-hcl` flag to
the `job inspect` command.

Closes: https://github.com/hashicorp/nomad/issues/6778

.changelog/23699.txt

@@ -0,0 +1,3 @@
+```release-note:improvement
+cli: Added option to return original HCL in `job inspect` command
+```

command/job_inspect.go

@@ -34,10 +34,17 @@ General Options:
 Inspect Options:
 
   -version <job version>
-    Display the job at the given job version.
+    Display the job at the given job version. Defaults to current version.
 
   -json
-    Output the job in its JSON format.
+    Output the job in its JSON format. Cannot be used with -hcl.
+
+  -hcl
+    Output the original HCL submitted with the job. Cannot be used with -json.
+
+  -with-vars
+    Include the original HCL2 variables submitted with the job. Can only be used
+    with -hcl.
 
   -t
     Format and display job using a Go template.
@@ -52,9 +59,11 @@ func (c *JobInspectCommand) Synopsis() string {
 func (c *JobInspectCommand) AutocompleteFlags() complete.Flags {
 	return mergeAutocompleteFlags(c.Meta.AutocompleteFlags(FlagSetClient),
 		complete.Flags{
-			"-version": complete.PredictAnything,
-			"-json":    complete.PredictNothing,
-			"-t":       complete.PredictAnything,
+			"-version":   complete.PredictAnything,
+			"-hcl":       complete.PredictNothing,
+			"-with-vars": complete.PredictNothing,
+			"-json":      complete.PredictNothing,
+			"-t":         complete.PredictAnything,
 		})
 }
 
@@ -76,12 +85,14 @@ func (c *JobInspectCommand) AutocompleteArgs() complete.Predictor {
 func (c *JobInspectCommand) Name() string { return "job inspect" }
 
 func (c *JobInspectCommand) Run(args []string) int {
-	var json bool
+	var json, hcl, withVars bool
 	var tmpl, versionStr string
 
 	flags := c.Meta.FlagSet(c.Name(), FlagSetClient)
 	flags.Usage = func() { c.Ui.Output(c.Help()) }
 	flags.BoolVar(&json, "json", false, "")
+	flags.BoolVar(&hcl, "hcl", false, "")
+	flags.BoolVar(&withVars, "with-vars", false, "")
 	flags.StringVar(&tmpl, "t", "", "")
 	flags.StringVar(&versionStr, "version", "", "")
 
@@ -90,6 +101,15 @@ func (c *JobInspectCommand) Run(args []string) int {
 	}
 	args = flags.Args()
 
+	if hcl && json {
+		c.Ui.Error("can only use one of -hcl or -json")
+		return 1
+	}
+	if withVars && !hcl {
+		c.Ui.Error("can only use -with-vars with -hcl")
+		return 1
+	}
+
 	// Get the HTTP client
 	client, err := c.Meta.Client()
 	if err != nil {
@@ -141,6 +161,21 @@ func (c *JobInspectCommand) Run(args []string) int {
 		version = &v
 	}
 
+	if hcl {
+		out, err := getJobHCL(client, namespace, jobID, version)
+		if err != nil {
+			c.Ui.Error(fmt.Sprintf("Error inspecting job: %s", err))
+			return 1
+		}
+		c.Ui.Output(out.Source)
+
+		if withVars {
+			c.Ui.Warn(getWithVarsOutput(namespace, jobID, out.Variables, out.VariableFlags))
+		}
+
+		return 0
+	}
+
 	// Prefix lookup matched a single job
 	job, err := getJob(client, namespace, jobID, version)
 	if err != nil {
@@ -206,3 +241,56 @@ func getJob(client *api.Client, namespace, jobID string, version *uint64) (*api.
 
 	return nil, fmt.Errorf("job %q with version %d couldn't be found", jobID, *version)
 }
+
+// getJob retrieves the job optionally at a particular version.
+func getJobHCL(client *api.Client, namespace, jobID string, version *uint64) (*api.JobSubmission, error) {
+	var q *api.QueryOptions
+	if namespace != "" {
+		q = &api.QueryOptions{Namespace: namespace}
+	}
+	v := uint64(0)
+	if version != nil {
+		v = *version
+	} else {
+		job, _, err := client.Jobs().Info(jobID, q)
+		if err != nil {
+			return nil, err
+		}
+		v = *job.Version
+	}
+	submission, _, err := client.Jobs().Submission(jobID, int(v), q)
+
+	if err != nil {
+		return nil, fmt.Errorf("job %q with version %d couldn't be found", jobID, version)
+	}
+	return submission, err
+}
+
+func getWithVarsOutput(namespace, jobID string, uiVars string, varsMap map[string]string) string {
+	runArgs := []string{}
+	if namespace != "" {
+		runArgs = append(runArgs, "-namespace")
+		runArgs = append(runArgs, namespace)
+	}
+
+	for k, v := range varsMap {
+		runArgs = append(runArgs, "-var")
+		runArgs = append(runArgs, fmt.Sprintf("%s=%s", k, v))
+	}
+	for _, uiVar := range strings.Split(uiVars, "\n") {
+		uiVar = strings.TrimSpace(uiVar)
+		if uiVar != "" {
+			runArgs = append(runArgs, "-var")
+			runArgs = append(runArgs, uiVar)
+		}
+	}
+	runArgs = append(runArgs, jobID)
+
+	return fmt.Sprintf(`
+To run this job as originally submitted:
+
+$ nomad job inspect -namespace %s -hcl %s |
+    nomad job run %s
+`, namespace, jobID, strings.Join(runArgs, " "))
+
+}

command/job_inspect_test.go

@@ -186,3 +186,37 @@ namespace "default" {
 		})
 	}
 }
+
+func TestInspectCommand_HCLVars(t *testing.T) {
+	ci.Parallel(t)
+
+	// no vars
+	out := getWithVarsOutput("default", "example", "", map[string]string{})
+	must.Eq(t, `
+To run this job as originally submitted:
+
+$ nomad job inspect -namespace default -hcl example |
+    nomad job run -namespace default example
+`, out)
+
+	// vars from the UI, erratic extra spaces
+	out = getWithVarsOutput("default", "example", "\n  http_port=foo  \n \nbar=baz ",
+		map[string]string{})
+	must.Eq(t, `
+To run this job as originally submitted:
+
+$ nomad job inspect -namespace default -hcl example |
+    nomad job run -namespace default -var http_port=foo -var bar=baz example
+`, out)
+
+	// same vars from the CLI
+	out = getWithVarsOutput("default", "example", "",
+		map[string]string{"http_port": "foo", "bar": "baz"})
+	must.Eq(t, `
+To run this job as originally submitted:
+
+$ nomad job inspect -namespace default -hcl example |
+    nomad job run -namespace default -var http_port=foo -var bar=baz example
+`, out)
+
+}

website/content/docs/commands/job/index.mdx

@@ -20,6 +20,7 @@ subcommands are available:
 - [`job dispatch`][dispatch] - Dispatch an instance of a parameterized job
 - [`job eval`][eval] - Force an evaluation for a job
 - [`job history`][history] - Display all tracked versions of a job
+- [`job inspect`][inspect] - Inspect the contents of a submitted job.
 - [`job promote`][promote] - Promote a job's canaries
 - [`job revert`][revert] - Revert to a prior version of the job
 - [`job status`][status] - Display status information about a job
@@ -28,6 +29,7 @@ subcommands are available:
 [dispatch]: /nomad/docs/commands/job/dispatch 'Dispatch an instance of a parameterized job'
 [eval]: /nomad/docs/commands/job/eval 'Force an evaluation for a job'
 [history]: /nomad/docs/commands/job/history 'Display all tracked versions of a job'
+[inspect]: /nomad/docs/commands/job/inspect
 [promote]: /nomad/docs/commands/job/promote "Promote a job's canaries"
 [revert]: /nomad/docs/commands/job/revert 'Revert to a prior version of the job'
 [status]: /nomad/docs/commands/job/status 'Display status information about a job'

website/content/docs/commands/job/inspect.mdx

@@ -33,7 +33,11 @@ run the command with a job prefix instead of the exact job ID.
 ## Inspect Options
 
 - `-version`: Display only the job at the given job version.
-- `-json` : Output the job in its JSON format.
+- `-json` : Output the job in its JSON format. Cannot be used with `-hcl`.
+- `-hcl`: Output the original HCL submitted with the job. Cannot be used with
+  `-json`.
+- `-with-vars`: Include the original HCL2 variables submitted with the job. Can
+    only be used with `-hcl`.
 - `-t` : Format and display the job using a Go template.
 
 ## Examples