LogDog: Add log rendering view.

appengine/logdog/coordinator/service.go

Index: appengine/logdog/coordinator/service.go
diff --git a/appengine/logdog/coordinator/service.go b/appengine/logdog/coordinator/service.go
index 660293f369eabeb116da508156d0ac1247a5319f..226955d261f1db536ebebcd99299af1f20faec35 100644
--- a/appengine/logdog/coordinator/service.go
+++ b/appengine/logdog/coordinator/service.go
@@ -9,6 +9,7 @@ import (
 	"github.com/luci/luci-go/common/gcloud/gs"
 	log "github.com/luci/luci-go/common/logging"
 	"github.com/luci/luci-go/server/logdog/storage"
+	"github.com/luci/luci-go/server/logdog/storage/archive"
 	"golang.org/x/net/context"
 )
 
@@ -16,12 +17,15 @@ import (
 // is primarily usable as a means of consistently stubbing out various external
 // components.
 type Service struct {
-	// StorageFunc is a function that generates an intermediate Storage instance
+	// IntermediateStorageFunc is a function that generates an intermediate Storage instance
 	// for use by this service. If nil, the production intermediate Storage
 	// instance will be used.
 	//
 	// This is provided for testing purposes.
-	StorageFunc func(context.Context) (storage.Storage, error)
+	IntermediateStorageFunc func(context.Context) (storage.Storage, error)
+
+	// ArchiveStorageFunc returns Archive storage for the specified log stream.
+	ArchiveStorageFunc func(context.Context, *LogStream) (storage.Storage, error)
 
 	// GSClientFunc is a function that generates a Google Storage client instance
 	// for use by this service. If nil, the production Google Storage Client will
@@ -29,32 +33,76 @@ type Service struct {
 	GSClientFunc func(context.Context) (gs.Client, error)
 }
 
-// Storage retrieves the configured Storage instance.
-func (s *Service) Storage(c context.Context) (storage.Storage, error) {
-	sf := s.StorageFunc
-	if sf == nil {
-		// Production: use BigTable storage.
-		sf = config.GetStorage
+// StorageForLogStream returns the Storage instance to use for a given
+// LogStream.
+//
+// The caller is responsible for calling Close on the returned Storage instance
+// when finished.
+func (s *Service) StorageForLogStream(c context.Context, ls *LogStream) (storage.Storage, error) {
+	if !ls.Archived() {
+		log.Debugf(c, "Log is not archived. Fetching from intermediate storage.")
+
+		// Logs are not archived. Fetch from intermediate storage.
+		return s.IntermediateStorage(c)
+	}
+
+	log.Debugf(c, "Log is archived. Fetching from archive storage.")
+	return s.ArchiveStorage(c, ls)
+}
+
+// IntermediateStorage retrieves the configured intermediate Storage instance.
+// The caller is responsible for calling Close on the returned Storage instance
+// when finished.
+func (s *Service) IntermediateStorage(c context.Context) (storage.Storage, error) {
+	if sf := s.IntermediateStorageFunc; sf != nil {
+		return sf(c)
+	}
+
+	// Production: use BigTable storage.
+	st, err := config.GetStorage(c)
+	if err != nil {
+		log.Errorf(log.SetError(c, err), "Failed to get BigTable Storage instance.")
+		return nil, err
+	}
+	return st, nil
+}
+
+// ArchiveStorage retrieves the configured archive Storage instance.
+// The caller is responsible for calling Close on the returned Storage instance
+// when finished.
+func (s *Service) ArchiveStorage(c context.Context, ls *LogStream) (storage.Storage, error) {
+	if sf := s.ArchiveStorageFunc; sf != nil {
+		return sf(c, ls)
+	}
+
+	gs, err := s.GSClient(c)
+	if err != nil {
+		log.WithError(err).Errorf(c, "Failed to create Google Storage client.")
+		return nil, err
 	}
 
-	st, err := sf(c)
+	st, err := archive.New(c, archive.Options{
+		IndexURL:  ls.ArchiveIndexURL,
+		StreamURL: ls.ArchiveStreamURL,
+		Client:    gs,
+	})
 	if err != nil {
-		log.Errorf(log.SetError(c, err), "Failed to get Storage instance.")
+		log.WithError(err).Errorf(c, "Failed to create Google Storage storage instance.")
 		return nil, err
 	}
 	return st, nil
 }
 
-// GSClient instantiates a Google Storage client.
+// GSClient instantiates a Google Storage client. The caller is responsible
+// for closing the client.
 func (s *Service) GSClient(c context.Context) (gs.Client, error) {
-	f := s.GSClientFunc
-	if f == nil {
-		f = gs.NewProdClient
+	if f := s.GSClientFunc; f != nil {
+		return f(c)
 	}
 
-	gsc, err := f(c)
+	gsc, err := gs.NewProdClient(c)
 	if err != nil {
-		log.Errorf(log.SetError(c, err), "Failed to get Google Storage client.")
+		log.Errorf(log.SetError(c, err), "Failed to get production Google Storage client.")
 		return nil, err
 	}
 	return gsc, nil