Allow optional hak releases

internal/pipeline/build.go

@@ -44,15 +44,16 @@ type BuildManifestHAK struct {
 	Priority    int      `json:"priority"`
 	MaxBytes    int64    `json:"max_bytes"`
 	SizeBytes   int64    `json:"size_bytes"`
+	Optional    bool     `json:"optional,omitempty"`
 	Assets      []string `json:"assets"`
 	ContentHash string   `json:"content_hash,omitempty"`
 }
 
 type assetResource struct {
-	Rel        string
-	Resource   erf.Resource
-	Size       int64
-	ChangedAt  time.Time
+	Rel       string
+	Resource  erf.Resource
+	Size      int64
+	ChangedAt time.Time
 }
 
 type hakChunk struct {
@@ -476,10 +477,10 @@ func collectAssetResources(p *project.Project) ([]assetResource, error) {
 			changedAt = info.ModTime()
 		}
 		hakResources = append(hakResources, assetResource{
-			Rel:        rel,
-			Resource:   resource,
-			Size:       erf.ArchiveSize([]erf.Resource{resource}),
-			ChangedAt:  changedAt,
+			Rel:       rel,
+			Resource:  resource,
+			Size:      erf.ArchiveSize([]erf.Resource{resource}),
+			ChangedAt: changedAt,
 		})
 	}
 
@@ -834,6 +835,7 @@ func buildManifestEntry(chunk hakChunk) BuildManifestHAK {
 		Priority:    chunk.Config.Priority,
 		MaxBytes:    chunk.Config.MaxBytes,
 		SizeBytes:   chunk.Size,
+		Optional:    chunk.Config.Optional,
 		Assets:      assets,
 		ContentHash: chunkContentHash(chunk),
 	}
@@ -845,6 +847,7 @@ func chunkContentHash(chunk hakChunk) string {
 	fmt.Fprintf(sum, "group:%s\n", chunk.Config.Name)
 	fmt.Fprintf(sum, "priority:%d\n", chunk.Config.Priority)
 	fmt.Fprintf(sum, "max_bytes:%d\n", chunk.Config.MaxBytes)
+	fmt.Fprintf(sum, "optional:%t\n", chunk.Config.Optional)
 	fmt.Fprintf(sum, "size_bytes:%d\n", chunk.Size)
 	for _, asset := range chunk.Assets {
 		fmt.Fprintf(sum, "asset:%s\n", asset.Rel)
@@ -993,7 +996,12 @@ func resolveModuleHAKOrder(p *project.Project, chunks []hakChunk) ([]string, err
 	}
 
 	byGroup := map[string][]string{}
+	optionalNames := map[string]struct{}{}
 	for _, chunk := range chunks {
+		if chunk.Config.Optional {
+			optionalNames[chunk.Name] = struct{}{}
+			continue
+		}
 		byGroup[chunk.Config.Name] = append(byGroup[chunk.Config.Name], chunk.Name)
 	}
 
@@ -1016,6 +1024,9 @@ func resolveModuleHAKOrder(p *project.Project, chunks []hakChunk) ([]string, err
 			continue
 		}
 
+		if _, optional := optionalNames[entry]; optional {
+			continue
+		}
 		if _, exists := seen[entry]; exists {
 			continue
 		}