add skip_save_build_region flag to fix naming conflicts when building for multiple regions

builder/amazon/common/ami_config.go

@@ -29,6 +29,7 @@ type AMIConfig struct {
 	SnapshotTags            TagMap            `mapstructure:"snapshot_tags"`
 	SnapshotUsers           []string          `mapstructure:"snapshot_users"`
 	SnapshotGroups          []string          `mapstructure:"snapshot_groups"`
+	AMISkipBuildRegion      bool              `mapstructure:"skip_save_build_region"`
 }
 
 func stringInSlice(s []string, searchstr string) bool {

builder/amazon/common/step_ami_region_copy.go

@@ -21,8 +21,9 @@ type StepAMIRegionCopy struct {
 	Name              string
 	OriginalRegion    string
 
-	toDelete      string
-	getRegionConn func(*AccessConfig, string) (ec2iface.EC2API, error)
+	toDelete           string
+	getRegionConn      func(*AccessConfig, string) (ec2iface.EC2API, error)
+	AMISkipBuildRegion bool
 }
 
 func (s *StepAMIRegionCopy) Run(ctx context.Context, state multistep.StateBag) multistep.StepAction {
@@ -33,7 +34,9 @@ func (s *StepAMIRegionCopy) Run(ctx context.Context, state multistep.StateBag) m
 	ami := amis[s.OriginalRegion]
 	// Always copy back into original region to preserve the ami name
 	s.toDelete = ami
-	s.Regions = append(s.Regions, s.OriginalRegion)
+	if !s.AMISkipBuildRegion {
+		s.Regions = append(s.Regions, s.OriginalRegion)
+	}
 
 	if s.EncryptBootVolume != nil && *s.EncryptBootVolume {
 		// encrypt_boot is true, so we have to copy the temporary

builder/amazon/common/step_pre_validate.go

@@ -18,8 +18,9 @@ import (
 // the build before actually doing any time consuming work
 //
 type StepPreValidate struct {
-	DestAmiName     string
-	ForceDeregister bool
+	DestAmiName        string
+	ForceDeregister    bool
+	AMISkipBuildRegion bool
 }
 
 func (s *StepPreValidate) Run(ctx context.Context, state multistep.StateBag) multistep.StepAction {
@@ -76,6 +77,10 @@ func (s *StepPreValidate) Run(ctx context.Context, state multistep.StateBag) mul
 		ui.Say("Force Deregister flag found, skipping prevalidating AMI Name")
 		return multistep.ActionContinue
 	}
+	if s.AMISkipBuildRegion {
+		ui.Say("skip_build_region was set; not prevalidating AMI name")
+		return multistep.ActionContinue
+	}
 
 	ec2conn := state.Get("ec2").(*ec2.EC2)
 

builder/amazon/ebs/builder.go

@@ -154,8 +154,9 @@ func (b *Builder) Run(ctx context.Context, ui packer.Ui, hook packer.Hook) (pack
 	// Build the steps
 	steps := []multistep.Step{
 		&awscommon.StepPreValidate{
-			DestAmiName:     b.config.AMIName,
-			ForceDeregister: b.config.AMIForceDeregister,
+			DestAmiName:        b.config.AMIName,
+			ForceDeregister:    b.config.AMIForceDeregister,
+			AMISkipBuildRegion: b.config.AMISkipBuildRegion,
 		},
 		&awscommon.StepSourceAMIInfo{
 			SourceAmi:                b.config.SourceAmi,
@@ -220,15 +221,18 @@ func (b *Builder) Run(ctx context.Context, ui packer.Ui, hook packer.Hook) (pack
 			AMIName:             b.config.AMIName,
 			Regions:             b.config.AMIRegions,
 		},
-		&stepCreateAMI{},
+		&stepCreateAMI{
+			AMISkipBuildRegion: b.config.AMISkipBuildRegion,
+		},
 		&awscommon.StepAMIRegionCopy{
-			AccessConfig:      &b.config.AccessConfig,
-			Regions:           b.config.AMIRegions,
-			AMIKmsKeyId:       b.config.AMIKmsKeyId,
-			RegionKeyIds:      b.config.AMIRegionKMSKeyIDs,
-			EncryptBootVolume: b.config.AMIEncryptBootVolume,
-			Name:              b.config.AMIName,
-			OriginalRegion:    *ec2conn.Config.Region,
+			AccessConfig:       &b.config.AccessConfig,
+			Regions:            b.config.AMIRegions,
+			AMIKmsKeyId:        b.config.AMIKmsKeyId,
+			RegionKeyIds:       b.config.AMIRegionKMSKeyIDs,
+			EncryptBootVolume:  b.config.AMIEncryptBootVolume,
+			Name:               b.config.AMIName,
+			OriginalRegion:     *ec2conn.Config.Region,
+			AMISkipBuildRegion: b.config.AMISkipBuildRegion,
 		},
 		&awscommon.StepModifyAMIAttributes{
 			Description:    b.config.AMIDescription,

builder/amazon/ebs/step_create_ami.go

@@ -14,7 +14,8 @@ import (
 )
 
 type stepCreateAMI struct {
-	image *ec2.Image
+	image              *ec2.Image
+	AMISkipBuildRegion bool
 }
 
 func (s *stepCreateAMI) Run(ctx context.Context, state multistep.StateBag) multistep.StepAction {
@@ -25,9 +26,9 @@ func (s *stepCreateAMI) Run(ctx context.Context, state multistep.StateBag) multi
 
 	// Create the image
 	amiName := config.AMIName
-	if config.AMIEncryptBootVolume != nil {
-		// encrypt_boot was set, so we will create a temporary image
-		// and then create a copy of it with the correct encrypt_boot
+	if config.AMIEncryptBootVolume != nil || s.AMISkipBuildRegion {
+		// Create a temporary image and then create a copy of it with the
+		// correct encrypt_boot
 		amiName = random.AlphaNum(7)
 	}