builder/amazon/common: AMIConfig common config

/cc @jmassara - I pulled out the AMI stuff into a common config
struct and also added in the new template stuff (that didn't exist
when you made the pull, so not your fault! :))

builder/amazon/common/ami_config.go

+package common
+
+import (
+	"fmt"
+	"github.com/mitchellh/packer/common"
+)
+
+// AMIConfig is for common configuration related to creating AMIs.
+type AMIConfig struct {
+	AMIName         string   `mapstructure:"ami_name"`
+	AMIDescription  string   `mapstructure:"ami_description"`
+	AMIUsers        []string `mapstructure:"ami_users"`
+	AMIGroups       []string `mapstructure:"ami_groups"`
+	AMIProductCodes []string `mapstructure:"ami_product_codes"`
+}
+
+func (c *AMIConfig) Prepare(t *common.Template) []error {
+	if t == nil {
+		var err error
+		t, err = common.NewTemplate()
+		if err != nil {
+			return []error{err}
+		}
+	}
+
+	templates := map[string]*string{
+		"ami_name":        &c.AMIName,
+		"ami_description": &c.AMIDescription,
+	}
+
+	errs := make([]error, 0)
+	for n, ptr := range templates {
+		var err error
+		*ptr, err = t.Process(*ptr, nil)
+		if err != nil {
+			errs = append(
+				errs, fmt.Errorf("Error processing %s: %s", n, err))
+		}
+	}
+
+	sliceTemplates := map[string][]string{
+		"ami_users":         c.AMIUsers,
+		"ami_groups":        c.AMIGroups,
+		"ami_product_codes": c.AMIProductCodes,
+	}
+
+	for n, slice := range sliceTemplates {
+		for i, elem := range slice {
+			var err error
+			slice[i], err = t.Process(elem, nil)
+			if err != nil {
+				errs = append(
+					errs, fmt.Errorf("Error processing %s[%d]: %s", n, i, err))
+			}
+		}
+	}
+
+	if c.AMIName == "" {
+		errs = append(errs, fmt.Errorf("ami_name must be specified"))
+	}
+
+	if len(errs) > 0 {
+		return errs
+	}
+
+	return nil
+}

builder/amazon/common/ami_config_test.go

+package common
+
+import (
+	"testing"
+)
+
+func testAMIConfig() *AMIConfig {
+	return &AMIConfig{
+		AMIName: "foo",
+	}
+}
+
+func TestAMIConfigPrepare_Region(t *testing.T) {
+	c := testAMIConfig()
+	if err := c.Prepare(nil); err != nil {
+		t.Fatalf("shouldn't have err: %s", err)
+	}
+
+	c.AMIName = ""
+	if err := c.Prepare(nil); err == nil {
+		t.Fatal("should have error")
+	}
+}

builder/amazon/ebs/builder.go

@@ -6,7 +6,6 @@
 package ebs
 
 import (
-	"errors"
 	"fmt"
 	"github.com/mitchellh/goamz/ec2"
 	"github.com/mitchellh/multistep"
@@ -22,16 +21,9 @@ const BuilderId = "mitchellh.amazonebs"
 type config struct {
 	common.PackerConfig    `mapstructure:",squash"`
 	awscommon.AccessConfig `mapstructure:",squash"`
+	awscommon.AMIConfig    `mapstructure:",squash"`
 	awscommon.RunConfig    `mapstructure:",squash"`
 
-	// Configuration of the resulting AMI
-	AMIName string `mapstructure:"ami_name"`
-
-	// AMI attributes
-	AMIDescription string   `mapstructure:"ami_description"`
-	AMIUsers       []string `mapstructure:"ami_users"`
-	AMIGroups      []string `mapstructure:"ami_groups"`
-
 	// Tags for the AMI
 	Tags map[string]string
 
@@ -57,17 +49,10 @@ func (b *Builder) Prepare(raws ...interface{}) error {
 	// Accumulate any errors
 	errs := common.CheckUnusedConfig(md)
 	errs = packer.MultiErrorAppend(errs, b.config.AccessConfig.Prepare(b.config.tpl)...)
+	errs = packer.MultiErrorAppend(errs, b.config.AMIConfig.Prepare(b.config.tpl)...)
 	errs = packer.MultiErrorAppend(errs, b.config.RunConfig.Prepare(b.config.tpl)...)
 
 	// Accumulate any errors
-	if b.config.AMIName == "" {
-		errs = packer.MultiErrorAppend(
-			errs, errors.New("ami_name must be specified"))
-	} else if b.config.AMIName, err = b.config.tpl.Process(b.config.AMIName, nil); err != nil {
-		errs = packer.MultiErrorAppend(
-			errs, fmt.Errorf("Error processing ami_name: %s", err))
-	}
-
 	newTags := make(map[string]string)
 	for k, v := range b.config.Tags {
 		k, err = b.config.tpl.Process(k, nil)

builder/amazon/instance/builder.go

@@ -23,10 +23,10 @@ const BuilderId = "mitchellh.amazon.instance"
 type Config struct {
 	common.PackerConfig    `mapstructure:",squash"`
 	awscommon.AccessConfig `mapstructure:",squash"`
+	awscommon.AMIConfig    `mapstructure:",squash"`
 	awscommon.RunConfig    `mapstructure:",squash"`
 
 	AccountId           string `mapstructure:"account_id"`
-	AMIName             string `mapstructure:"ami_name"`
 	BundleDestination   string `mapstructure:"bundle_destination"`
 	BundlePrefix        string `mapstructure:"bundle_prefix"`
 	BundleUploadCommand string `mapstructure:"bundle_upload_command"`
@@ -37,12 +37,6 @@ type Config struct {
 	X509KeyPath         string `mapstructure:"x509_key_path"`
 	X509UploadPath      string `mapstructure:"x509_upload_path"`
 
-	// AMI attributes
-	AMIDescription  string   `mapstructure:"ami_description"`
-	AMIUsers        []string `mapstructure:"ami_users"`
-	AMIGroups       []string `mapstructure:"ami_groups"`
-	AMIProductCodes []string `mapstructure:"ami_product_codes"`
-
 	tpl *common.Template
 }
 
@@ -100,6 +94,7 @@ func (b *Builder) Prepare(raws ...interface{}) error {
 	// Accumulate any errors
 	errs := common.CheckUnusedConfig(md)
 	errs = packer.MultiErrorAppend(errs, b.config.AccessConfig.Prepare(b.config.tpl)...)
+	errs = packer.MultiErrorAppend(errs, b.config.AMIConfig.Prepare(b.config.tpl)...)
 	errs = packer.MultiErrorAppend(errs, b.config.RunConfig.Prepare(b.config.tpl)...)
 
 	validates := map[string]*string{
@@ -140,11 +135,6 @@ func (b *Builder) Prepare(raws ...interface{}) error {
 		b.config.AccountId = strings.Replace(b.config.AccountId, "-", "", -1)
 	}
 
-	if b.config.AMIName == "" {
-		errs = packer.MultiErrorAppend(
-			errs, errors.New("ami_name must be specified"))
-	}
-
 	if b.config.S3Bucket == "" {
 		errs = packer.MultiErrorAppend(errs, errors.New("s3_bucket is required"))
 	}