hcp: support for multiple build block with hcl2

prepend the build block name to the component name before making any
request to hcp server

internal/hcp/registry/hcl.go

@@ -69,7 +69,8 @@ func (h *HCLRegistry) StartBuild(ctx context.Context, build sdkpacker.Build) err
 	name := build.Name()
 	cb, ok := build.(*packer.CoreBuild)
 	if ok {
-		name = cb.Type
+		// We prepend type with builder block name to prevent conflict
+		name = fmt.Sprintf("%s.%s", cb.BuildName, cb.Type)
 	}
 
 	return h.bucket.startBuild(ctx, name)
@@ -85,7 +86,8 @@ func (h *HCLRegistry) CompleteBuild(
 	buildName := build.Name()
 	cb, ok := build.(*packer.CoreBuild)
 	if ok {
-		buildName = cb.Type
+		// We prepend type with builder block name to prevent conflict
+		buildName = fmt.Sprintf("%s.%s", cb.BuildName, cb.Type)
 	}
 
 	buildMetadata, envMetadata := cb.GetMetadata(), h.metadata
@@ -103,18 +105,6 @@ func (h *HCLRegistry) VersionStatusSummary() {
 
 func NewHCLRegistry(config *hcl2template.PackerConfig, ui sdkpacker.Ui) (*HCLRegistry, hcl.Diagnostics) {
 	var diags hcl.Diagnostics
-	if len(config.Builds) > 1 {
-		diags = append(diags, &hcl.Diagnostic{
-			Severity: hcl.DiagError,
-			Summary:  "Multiple " + buildLabel + " blocks",
-			Detail: fmt.Sprintf("For HCP Packer Registry enabled builds, only one " + buildLabel +
-				" block can be defined. Please remove any additional " + buildLabel +
-				" block(s). If this " + buildLabel + " is not meant for the HCP Packer registry please " +
-				"clear any HCP_PACKER_* environment variables."),
-		})
-
-		return nil, diags
-	}
 
 	withHCLBucketConfiguration := func(bb *hcl2template.BuildBlock) bucketConfigurationOpts {
 		return func(bucket *Bucket) hcl.Diagnostics {
@@ -155,8 +145,13 @@ func NewHCLRegistry(config *hcl2template.PackerConfig, ui sdkpacker.Ui) (*HCLReg
 		return nil, diags
 	}
 
-	for _, source := range build.Sources {
-		bucket.RegisterBuildForComponent(source.String())
+	for _, build := range config.Builds {
+		for _, source := range build.Sources {
+
+			// We prepend each source with builder block name to prevent conflict
+			buildName := fmt.Sprintf("%s.%s", build.Name, source.String())
+			bucket.RegisterBuildForComponent(buildName)
+		}
 	}
 
 	ui.Say(fmt.Sprintf("Tracking build on HCP Packer with fingerprint %q", bucket.Version.Fingerprint))

internal/hcp/registry/types.bucket.go

@@ -132,16 +132,15 @@ func (bucket *Bucket) Initialize(
 	return bucket.initializeVersion(ctx, templateType)
 }
 
-func (bucket *Bucket) RegisterBuildForComponent(sourceName string) {
+func (bucket *Bucket) RegisterBuildForComponent(buildName string) {
 	if bucket == nil {
 		return
 	}
 
-	if ok := bucket.Version.HasBuild(sourceName); ok {
+	if ok := bucket.Version.HasBuild(buildName); ok {
 		return
 	}
-
-	bucket.Version.expectedBuilds = append(bucket.Version.expectedBuilds, sourceName)
+	bucket.Version.expectedBuilds = append(bucket.Version.expectedBuilds, buildName)
 }
 
 // CreateInitialBuildForVersion will create a build entry on the HCP Packer Registry for the named componentType.
@@ -658,7 +657,7 @@ func (bucket *Bucket) doCompleteBuild(
 	ctx context.Context,
 	buildName string,
 	packerSDKArtifacts []packerSDK.Artifact,
-	buildErr error,
+	_ error,
 ) ([]packerSDK.Artifact, error) {
 	for _, art := range packerSDKArtifacts {
 		var sdkImages []packerSDKRegistry.Image