add JSON support

command/deploy.go

@@ -87,6 +87,9 @@ General Options:
     Specify the format of Levant's logs. Valid values are HUMAN or JSON. The
     default is HUMAN.
 
+  -json
+	Process template file as JSON
+
   -var-file=<file>
     Path to a file containing user variables used when rendering the job
     template. You can repeat this flag multiple times to supply multiple
@@ -129,6 +132,7 @@ func (c *DeployCommand) Run(args []string) int {
 	flags.StringVar(&format, "log-format", "HUMAN", "")
 	flags.StringVar(&config.Deploy.VaultToken, "vault-token", "", "")
 	flags.BoolVar(&config.Deploy.EnvVault, "vault", false, "")
+	flags.BoolVar(&config.Template.IsJSON, "json", false, "")
 
 	flags.Var((*helper.FlagStringSlice)(&config.Template.VariableFiles), "var-file", "")
 
@@ -163,7 +167,7 @@ func (c *DeployCommand) Run(args []string) int {
 	}
 
 	config.Template.Job, err = template.RenderJob(config.Template.TemplateFile,
-		config.Template.VariableFiles, config.Client.ConsulAddr, &c.Meta.flagVars)
+		config.Template.VariableFiles, config.Client.ConsulAddr, &c.Meta.flagVars, config.Template.IsJSON)
 	if err != nil {
 		c.UI.Error(fmt.Sprintf("[ERROR] levant/command: %v", err))
 		return 1

command/deploy_test.go

@@ -33,7 +33,7 @@ func TestDeploy_checkCanaryAutoPromote(t *testing.T) {
 	}
 
 	for i, c := range cases {
-		job, err := template.RenderJob(c.File, []string{}, "", &fVars)
+		job, err := template.RenderJob(c.File, []string{}, "", &fVars, false)
 		if err != nil {
 			t.Fatalf("case %d failed: %v", i, err)
 		}
@@ -64,7 +64,7 @@ func TestDeploy_checkForceBatch(t *testing.T) {
 	}
 
 	for i, c := range cases {
-		job, err := template.RenderJob(c.File, []string{}, "", &fVars)
+		job, err := template.RenderJob(c.File, []string{}, "", &fVars, false)
 		if err != nil {
 			t.Fatalf("case %d failed: %v", i, err)
 		}

command/plan.go

@@ -67,6 +67,9 @@ General Options:
     Specify the format of Levant's logs. Valid values are HUMAN or JSON. The
     default is HUMAN.
 
+  -json
+    Process template file as JSON
+
   -var-file=<file>
     Path to a file containing user variables used when rendering the job
     template. You can repeat this flag multiple times to supply multiple
@@ -101,6 +104,7 @@ func (c *PlanCommand) Run(args []string) int {
 	flags.BoolVar(&config.Plan.IgnoreNoChanges, "ignore-no-changes", false, "")
 	flags.StringVar(&level, "log-level", "INFO", "")
 	flags.StringVar(&format, "log-format", "HUMAN", "")
+	flags.BoolVar(&config.Template.IsJSON, "json", false, "")
 	flags.Var((*helper.FlagStringSlice)(&config.Template.VariableFiles), "var-file", "")
 
 	if err = flags.Parse(args); err != nil {
@@ -128,7 +132,7 @@ func (c *PlanCommand) Run(args []string) int {
 	}
 
 	config.Template.Job, err = template.RenderJob(config.Template.TemplateFile,
-		config.Template.VariableFiles, config.Client.ConsulAddr, &c.Meta.flagVars)
+		config.Template.VariableFiles, config.Client.ConsulAddr, &c.Meta.flagVars, config.Template.IsJSON)
 
 	if err != nil {
 		c.UI.Error(fmt.Sprintf("[ERROR] levant/command: %v", err))

levant/structs/config.go

@@ -86,6 +86,10 @@ type TemplateConfig struct {
 	// VariableFiles contains the variables which will be substituted into the
 	// templateFile before deployment.
 	VariableFiles []string
+
+	// VariableFiles contains the variables which will be substituted into the
+	// templateFile before deployment.
+	IsJSON bool
 }
 
 // ScaleConfig contains all the scaling specific configuration options.

template/render.go

@@ -22,13 +22,37 @@ import (
 
 // RenderJob takes in a template and variables performing a render of the
 // template followed by Nomad jobspec parse.
-func RenderJob(templateFile string, variableFiles []string, addr string, flagVars *map[string]interface{}) (job *nomad.Job, err error) {
+func RenderJob(templateFile string, variableFiles []string, addr string, flagVars *map[string]interface{}, isJSON bool) (job *nomad.Job, err error) {
 	var tpl *bytes.Buffer
 	tpl, err = RenderTemplate(templateFile, variableFiles, addr, flagVars)
 	if err != nil {
 		return
 	}
 
+	if isJSON {
+		// Support JSON files with both a top-level Job key as well as
+		// ones without.
+		eitherJob := struct {
+			NestedJob *nomad.Job `json:"Job"`
+			nomad.Job
+		}{}
+
+		if err := json.NewDecoder(tpl).Decode(&eitherJob); err != nil {
+			return nil, fmt.Errorf("Failed to parse JSON job: %w", err)
+		}
+
+		if eitherJob.NestedJob != nil {
+			if eitherJob.NestedJob.Name == nil && eitherJob.NestedJob.ID != nil {
+				eitherJob.NestedJob.Name = eitherJob.NestedJob.ID
+			}
+			if eitherJob.NestedJob.ID == nil {
+				return nil, fmt.Errorf("JSON is missing ID field")
+			}
+			return eitherJob.NestedJob, nil
+		}
+		return &eitherJob.Job, nil
+	}
+
 	return jobspec.Parse(tpl)
 }
 

template/render_test.go

@@ -28,7 +28,7 @@ func TestTemplater_RenderTemplate(t *testing.T) {
 	fVars := make(map[string]interface{})
 
 	// Test basic TF template render.
-	job, err = RenderJob("test-fixtures/single_templated.nomad", []string{"test-fixtures/test.tf"}, "", &fVars)
+	job, err = RenderJob("test-fixtures/single_templated.nomad", []string{"test-fixtures/test.tf"}, "", &fVars, false)
 	if err != nil {
 		t.Fatal(err)
 	}
@@ -40,7 +40,7 @@ func TestTemplater_RenderTemplate(t *testing.T) {
 	}
 
 	// Test basic YAML template render.
-	job, err = RenderJob("test-fixtures/single_templated.nomad", []string{"test-fixtures/test.yaml"}, "", &fVars)
+	job, err = RenderJob("test-fixtures/single_templated.nomad", []string{"test-fixtures/test.yaml"}, "", &fVars, false)
 	if err != nil {
 		t.Fatal(err)
 	}
@@ -52,7 +52,7 @@ func TestTemplater_RenderTemplate(t *testing.T) {
 	}
 
 	// Test multiple var-files
-	job, err = RenderJob("test-fixtures/single_templated.nomad", []string{"test-fixtures/test.yaml", "test-fixtures/test-overwrite.yaml"}, "", &fVars)
+	job, err = RenderJob("test-fixtures/single_templated.nomad", []string{"test-fixtures/test.yaml", "test-fixtures/test-overwrite.yaml"}, "", &fVars, false)
 	if err != nil {
 		t.Fatal(err)
 	}
@@ -61,7 +61,7 @@ func TestTemplater_RenderTemplate(t *testing.T) {
 	}
 
 	// Test multiple var-files of different types
-	job, err = RenderJob("test-fixtures/single_templated.nomad", []string{"test-fixtures/test.tf", "test-fixtures/test-overwrite.yaml"}, "", &fVars)
+	job, err = RenderJob("test-fixtures/single_templated.nomad", []string{"test-fixtures/test.tf", "test-fixtures/test-overwrite.yaml"}, "", &fVars, false)
 	if err != nil {
 		t.Fatal(err)
 	}
@@ -71,7 +71,7 @@ func TestTemplater_RenderTemplate(t *testing.T) {
 
 	// Test multiple var-files with var-args
 	fVars["job_name"] = testJobNameOverwrite2
-	job, err = RenderJob("test-fixtures/single_templated.nomad", []string{"test-fixtures/test.tf", "test-fixtures/test-overwrite.yaml"}, "", &fVars)
+	job, err = RenderJob("test-fixtures/single_templated.nomad", []string{"test-fixtures/test.tf", "test-fixtures/test-overwrite.yaml"}, "", &fVars, false)
 	if err != nil {
 		t.Fatal(err)
 	}
@@ -80,7 +80,7 @@ func TestTemplater_RenderTemplate(t *testing.T) {
 	}
 
 	// Test empty var-args and empty variable file render.
-	job, err = RenderJob("test-fixtures/none_templated.nomad", []string{}, "", &fVars)
+	job, err = RenderJob("test-fixtures/none_templated.nomad", []string{}, "", &fVars, false)
 	if err != nil {
 		t.Fatal(err)
 	}
@@ -90,7 +90,7 @@ func TestTemplater_RenderTemplate(t *testing.T) {
 
 	// Test var-args only render.
 	fVars = map[string]interface{}{"job_name": testJobName, "task_resource_cpu": "1313"}
-	job, err = RenderJob("test-fixtures/single_templated.nomad", []string{}, "", &fVars)
+	job, err = RenderJob("test-fixtures/single_templated.nomad", []string{}, "", &fVars, false)
 	if err != nil {
 		t.Fatal(err)
 	}
@@ -105,7 +105,7 @@ func TestTemplater_RenderTemplate(t *testing.T) {
 	delete(fVars, "job_name")
 	fVars["datacentre"] = testDCName
 	os.Setenv(testEnvName, testEnvValue)
-	job, err = RenderJob("test-fixtures/multi_templated.nomad", []string{"test-fixtures/test.yaml"}, "", &fVars)
+	job, err = RenderJob("test-fixtures/multi_templated.nomad", []string{"test-fixtures/test.yaml"}, "", &fVars, false)
 	if err != nil {
 		t.Fatal(err)
 	}

test/acctest/acctest.go

@@ -83,6 +83,9 @@ func Test(t *testing.T, c TestCase) {
 						break
 					}
 				}
+			} else if step.ExpectErr {
+				t.Errorf("step %d/%d failed not but was expected to fail", stepNum, len(c.Steps))
+				break
 			}
 		}
 

test/acctest/deploy.go

@@ -20,6 +20,7 @@ type DeployTestStepRunner struct {
 	Canary     int
 	ForceBatch bool
 	ForceCount bool
+	IsJSON     bool
 }
 
 // Run renders the job fixture and triggers a deployment
@@ -29,7 +30,7 @@ func (c DeployTestStepRunner) Run(s *TestState) error {
 	}
 	c.Vars["job_name"] = s.JobName
 
-	job, err := template.RenderJob("fixtures/"+c.FixtureName, []string{}, "", &c.Vars)
+	job, err := template.RenderJob("fixtures/"+c.FixtureName, []string{}, "", &c.Vars, c.IsJSON)
 	if err != nil {
 		return fmt.Errorf("error rendering template: %s", err)
 	}
@@ -42,7 +43,8 @@ func (c DeployTestStepRunner) Run(s *TestState) error {
 		},
 		Client: &structs.ClientConfig{},
 		Template: &structs.TemplateConfig{
-			Job: job,
+			Job:    job,
+			IsJSON: c.IsJSON,
 		},
 	}
 

test/deploy_test.go

@@ -23,6 +23,75 @@ func TestDeploy_basic(t *testing.T) {
 	})
 }
 
+func TestDeploy_basicJson(t *testing.T) {
+	acctest.Test(t, acctest.TestCase{
+		Steps: []acctest.TestStep{
+			{
+				Runner: acctest.DeployTestStepRunner{
+					FixtureName: "deploy_basic.nomad.json",
+					IsJSON:      true,
+				},
+				Check: acctest.CheckDeploymentStatus("successful"),
+			},
+		},
+		CleanupFunc: acctest.CleanupPurgeJob,
+	})
+}
+
+func TestDeploy_invalidJson(t *testing.T) {
+	acctest.Test(t, acctest.TestCase{
+		Steps: []acctest.TestStep{
+			{
+				Runner: acctest.DeployTestStepRunner{
+					FixtureName: "deploy_basic_invalid.nomad.json",
+					IsJSON:      true,
+				},
+				ExpectErr: true,
+				CheckErr: func(err error) bool {
+					return err.Error() == "error rendering template: Failed to parse JSON job: json: cannot unmarshal array into Go struct field Job.Job.Type of type string"
+				},
+			},
+		},
+		CleanupFunc: acctest.CleanupPurgeJob,
+	})
+}
+
+func TestDeploy_jsonWithoutIdName(t *testing.T) {
+	acctest.Test(t, acctest.TestCase{
+		Steps: []acctest.TestStep{
+			{
+				Runner: acctest.DeployTestStepRunner{
+					FixtureName: "deploy_jsonWithoutIdName.nomad.json",
+					IsJSON:      true,
+				},
+				ExpectErr: true,
+				CheckErr: func(err error) bool {
+					return err.Error() == "error rendering template: JSON is missing ID field"
+				},
+			},
+		},
+		CleanupFunc: acctest.CleanupPurgeJob,
+	})
+}
+
+func TestDeploy_notJson(t *testing.T) {
+	acctest.Test(t, acctest.TestCase{
+		Steps: []acctest.TestStep{
+			{
+				Runner: acctest.DeployTestStepRunner{
+					FixtureName: "deploy_basic.nomad",
+					IsJSON:      true,
+				},
+				ExpectErr: true,
+				CheckErr: func(err error) bool {
+					return err.Error() == "error rendering template: Detected JSON but failed to parse JSON job: invalid character '#' looking for beginning of value"
+				},
+			},
+		},
+		CleanupFunc: acctest.CleanupPurgeJob,
+	})
+}
+
 func TestDeploy_driverError(t *testing.T) {
 	acctest.Test(t, acctest.TestCase{
 		Steps: []acctest.TestStep{

test/fixtures/deploy_basic.nomad.json

@@ -0,0 +1,48 @@
+{
+    "Job": {
+        "ID": "[[.job_name]]",
+        "Type": "service",
+        "Datacenters": [
+            "dc1"
+        ],
+        "TaskGroups": [
+            {
+                "Name": "test",
+                "Count": 1,
+                "Tasks": [
+                    {
+                        "Name": "alpine",
+                        "Driver": "docker",
+                        "Config": {
+                            "args": [
+                                "-f",
+                                "/dev/null"
+                            ],
+                            "command": "tail",
+                            "image": "alpine"
+                        },
+                        "Resources": {
+                            "CPU": 100,
+                            "MemoryMB": 128
+                        }
+                    }
+                ],
+                "RestartPolicy": {
+                    "Interval": 300000000000,
+                    "Attempts": 10,
+                    "Delay": 25000000000,
+                    "Mode": "delay"
+                },
+                "EphemeralDisk": {
+                    "SizeMB": 300
+                }
+            }
+        ],
+        "Update": {
+            "MaxParallel": 1,
+            "MinHealthyTime": 10000000000,
+            "HealthyDeadline": 60000000000,
+            "AutoRevert": true
+        }
+    }
+}