builder/amazonebs: Tests for invalid AMI name

builder/amazonebs/builder.go

@@ -15,6 +15,7 @@ import (
 	"github.com/mitchellh/packer/builder/common"
 	"github.com/mitchellh/packer/packer"
 	"log"
+	"text/template"
 	"time"
 )
 
@@ -98,6 +99,15 @@ func (b *Builder) Prepare(raws ...interface{}) error {
 		errs = append(errs, fmt.Errorf("Failed parsing ssh_timeout: %s", err))
 	}
 
+	if b.config.AMIName == "" {
+		errs = append(errs, errors.New("ami_name must be specified"))
+	} else {
+		_, err = template.New("ami").Parse(b.config.AMIName)
+		if err != nil {
+			errs = append(errs, fmt.Errorf("Failed parsing ami_name: %s", err))
+		}
+	}
+
 	if len(errs) > 0 {
 		return &packer.MultiError{errs}
 	}

builder/amazonebs/builder_test.go

@@ -13,6 +13,7 @@ func testConfig() map[string]interface{} {
 		"instance_type": "foo",
 		"region":        "us-east-1",
 		"ssh_username":  "root",
+		"ami_name":      "foo",
 	}
 }
 
@@ -60,6 +61,34 @@ func TestBuilderPrepare_AccessKey(t *testing.T) {
 	}
 }
 
+func TestBuilderPrepare_AMIName(t *testing.T) {
+	var b Builder
+	config := testConfig()
+
+	// Test good
+	config["ami_name"] = "foo"
+	err := b.Prepare(config)
+	if err != nil {
+		t.Fatalf("should not have error: %s", err)
+	}
+
+	// Test bad
+	config["ami_name"] = "foo {{"
+	b = Builder{}
+	err = b.Prepare(config)
+	if err == nil {
+		t.Fatal("should have error")
+	}
+
+	// Test bad
+	delete(config, "ami_name")
+	b = Builder{}
+	err = b.Prepare(config)
+	if err == nil {
+		t.Fatal("should have error")
+	}
+}
+
 func TestBuilderPrepare_InstanceType(t *testing.T) {
 	var b Builder
 	config := testConfig()

builder/amazonebs/step_create_ami.go

@@ -29,11 +29,7 @@ func (s *stepCreateAMI) Run(state map[string]interface{}) multistep.StepAction {
 		strconv.FormatInt(time.Now().UTC().Unix(), 10),
 	}
 
-	t, err := template.New("ami").Parse(config.AMIName)
-	if err != nil {
-		ui.Error(err.Error())
-		return multistep.ActionHalt
-	}
+	t := template.Must(template.New("ami").Parse(config.AMIName))
 	t.Execute(amiNameBuf, tData)
 	amiName := amiNameBuf.String()