Move storage providers (#1919)

This change moves the individual storage providers to the corresponding implementation packages. This makes the server package agnostic of storage implementations, and makes it the responsibility of main.go files to import them.

CHANGELOG.md

@@ -23,7 +23,10 @@ SetAndVerifyMapLeaves method was deleted.
 The StorageProvider type and helpers have been moved from the server package to
 storage. Aliases for the old types/functions are created for backward
 compatibility, but the new code should not use them as we will remove them with
-the next major version bump.
+the next major version bump. The individual storage providers have been moved to
+the corresponding packages, and are now required to be imported explicitly by
+the main file in order to be registered. We are including only MySQL and
+cloudspanner providers by default, since these are the ones that we support.
 
 ## v1.3.2 - Module fixes
 

server/mysql_quota_provider.go

@@ -20,6 +20,7 @@ import (
 	"github.com/golang/glog"
 	"github.com/google/trillian/quota"
 	"github.com/google/trillian/quota/mysqlqm"
+	"github.com/google/trillian/storage/mysql"
 )
 
 // QuotaMySQL represents the MySQL quota implementation.
@@ -37,7 +38,7 @@ func init() {
 }
 
 func newMySQLQuotaManager() (quota.Manager, error) {
-	db, err := getMySQLDatabase()
+	db, err := mysql.GetDatabase()
 	if err != nil {
 		return nil, err
 	}

server/trillian_log_server/main.go

@@ -48,6 +48,10 @@ import (
 	_ "github.com/google/trillian/crypto/keys/pem/proto"
 	_ "github.com/google/trillian/crypto/keys/pkcs11/proto"
 
+	// Register supported storage providers.
+	_ "github.com/google/trillian/storage/cloudspanner"
+	_ "github.com/google/trillian/storage/mysql"
+
 	// Load hashers
 	_ "github.com/google/trillian/merkle/rfc6962"
 )

server/trillian_log_signer/main.go

@@ -48,6 +48,10 @@ import (
 	_ "github.com/google/trillian/crypto/keys/pem/proto"
 	_ "github.com/google/trillian/crypto/keys/pkcs11/proto"
 
+	// Register supported storage providers.
+	_ "github.com/google/trillian/storage/cloudspanner"
+	_ "github.com/google/trillian/storage/mysql"
+
 	// Load hashers
 	_ "github.com/google/trillian/merkle/rfc6962"
 )

server/trillian_map_server/main.go

@@ -45,6 +45,10 @@ import (
 	_ "github.com/google/trillian/crypto/keys/pem/proto"
 	_ "github.com/google/trillian/crypto/keys/pkcs11/proto"
 
+	// Register supported storage providers.
+	_ "github.com/google/trillian/storage/cloudspanner"
+	_ "github.com/google/trillian/storage/mysql"
+
 	// Load hashers
 	_ "github.com/google/trillian/merkle/coniks"
 	_ "github.com/google/trillian/merkle/maphasher"

server/cloudspanner_storage_provider.go → storage/cloudspanner/storage_provider.go

@@ -12,7 +12,7 @@
 // See the License for the specific language governing permissions and
 // limitations under the License.
 
-package server
+package cloudspanner
 
 import (
 	"bytes"
@@ -28,7 +28,6 @@ import (
 	"github.com/golang/glog"
 	"github.com/google/trillian/monitoring"
 	"github.com/google/trillian/storage"
-	"github.com/google/trillian/storage/cloudspanner"
 )
 
 var (
@@ -50,7 +49,7 @@ var (
 )
 
 func init() {
-	if err := RegisterStorageProvider("cloud_spanner", newCloudSpannerStorageProvider); err != nil {
+	if err := storage.RegisterProvider("cloud_spanner", newCloudSpannerStorageProvider); err != nil {
 		panic(err)
 	}
 }
@@ -88,7 +87,7 @@ func configFromFlags() spanner.ClientConfig {
 	return r
 }
 
-func newCloudSpannerStorageProvider(_ monitoring.MetricFactory) (StorageProvider, error) {
+func newCloudSpannerStorageProvider(_ monitoring.MetricFactory) (storage.Provider, error) {
 	csMu.Lock()
 	defer csMu.Unlock()
 
@@ -109,7 +108,7 @@ func newCloudSpannerStorageProvider(_ monitoring.MetricFactory) (StorageProvider
 // LogStorage builds and returns a new storage.LogStorage using CloudSpanner.
 func (s *cloudSpannerProvider) LogStorage() storage.LogStorage {
 	warn()
-	opts := cloudspanner.LogStorageOptions{}
+	opts := LogStorageOptions{}
 	frac := *csDequeueAcrossMerkleBucketsFraction
 	if frac > 1.0 {
 		frac = 1.0
@@ -121,23 +120,23 @@ func (s *cloudSpannerProvider) LogStorage() storage.LogStorage {
 	if *csReadOnlyStaleness > 0 {
 		opts.ReadOnlyStaleness = *csReadOnlyStaleness
 	}
-	return cloudspanner.NewLogStorageWithOpts(s.client, opts)
+	return NewLogStorageWithOpts(s.client, opts)
 }
 
 // MapStorage builds and returns a new storage.MapStorage using CloudSpanner.
 func (s *cloudSpannerProvider) MapStorage() storage.MapStorage {
 	warn()
-	opts := cloudspanner.MapStorageOptions{}
+	opts := MapStorageOptions{}
 	if *csReadOnlyStaleness > 0 {
 		opts.ReadOnlyStaleness = *csReadOnlyStaleness
 	}
-	return cloudspanner.NewMapStorageWithOpts(s.client, opts)
+	return NewMapStorageWithOpts(s.client, opts)
 }
 
 // AdminStorage builds and returns a new storage.AdminStorage using CloudSpanner.
 func (s *cloudSpannerProvider) AdminStorage() storage.AdminStorage {
 	warn()
-	return cloudspanner.NewAdminStorage(s.client)
+	return NewAdminStorage(s.client)
 }
 
 // Close shuts down this provider. Calls to the other methods will fail

server/memory_storage_provider.go → storage/memory/provider.go

@@ -12,43 +12,42 @@
 // See the License for the specific language governing permissions and
 // limitations under the License.
 
-package server
+package memory
 
 import (
 	"github.com/golang/glog"
 	"github.com/google/trillian/monitoring"
 	"github.com/google/trillian/storage"
-	"github.com/google/trillian/storage/memory"
 )
 
 func init() {
-	if err := RegisterStorageProvider("memory", newMemoryStorageProvider); err != nil {
+	if err := storage.RegisterProvider("memory", newMemoryStorageProvider); err != nil {
 		glog.Fatalf("Failed to register storage provider memory: %v", err)
 	}
 }
 
 type memProvider struct {
 	mf monitoring.MetricFactory
-	ts *memory.TreeStorage
+	ts *TreeStorage
 }
 
-func newMemoryStorageProvider(mf monitoring.MetricFactory) (StorageProvider, error) {
+func newMemoryStorageProvider(mf monitoring.MetricFactory) (storage.Provider, error) {
 	return &memProvider{
 		mf: mf,
-		ts: memory.NewTreeStorage(),
+		ts: NewTreeStorage(),
 	}, nil
 }
 
 func (s *memProvider) LogStorage() storage.LogStorage {
-	return memory.NewLogStorage(s.ts, s.mf)
+	return NewLogStorage(s.ts, s.mf)
 }
 
 func (s *memProvider) MapStorage() storage.MapStorage {
 	return nil
 }
 
 func (s *memProvider) AdminStorage() storage.AdminStorage {
-	return memory.NewAdminStorage(s.ts)
+	return NewAdminStorage(s.ts)
 }
 
 func (s *memProvider) Close() error {

server/memory_storage_provider_test.go → storage/memory/provider_test.go

@@ -12,14 +12,16 @@
 // See the License for the specific language governing permissions and
 // limitations under the License.
 
-package server
+package memory
 
 import (
 	"testing"
+
+	"github.com/google/trillian/storage"
 )
 
 func TestMemoryStorageProvider(t *testing.T) {
-	sp, err := NewStorageProvider("memory", nil)
+	sp, err := storage.NewProvider("memory", nil)
 	if err != nil {
 		t.Fatalf("Got an unexpected error: %v", err)
 	}
@@ -29,7 +31,7 @@ func TestMemoryStorageProvider(t *testing.T) {
 }
 
 func TestMemoryStorageProviderLogStorage(t *testing.T) {
-	sp, err := NewStorageProvider("memory", nil)
+	sp, err := storage.NewProvider("memory", nil)
 	if err != nil {
 		t.Fatalf("Got an unexpected error: %v", err)
 	}
@@ -41,7 +43,7 @@ func TestMemoryStorageProviderLogStorage(t *testing.T) {
 }
 
 func TestMemoryStorageProviderMapStorage(t *testing.T) {
-	sp, err := NewStorageProvider("memory", nil)
+	sp, err := storage.NewProvider("memory", nil)
 	if err != nil {
 		t.Fatalf("Got an unexpected error: %v", err)
 	}
@@ -53,7 +55,7 @@ func TestMemoryStorageProviderMapStorage(t *testing.T) {
 }
 
 func TestMemoryStorageProviderAdminStorage(t *testing.T) {
-	sp, err := NewStorageProvider("memory", nil)
+	sp, err := storage.NewProvider("memory", nil)
 	if err != nil {
 		t.Fatalf("Got an unexpected error: %v", err)
 	}
@@ -65,7 +67,7 @@ func TestMemoryStorageProviderAdminStorage(t *testing.T) {
 }
 
 func TestMemoryStorageProviderClose(t *testing.T) {
-	sp, err := NewStorageProvider("memory", nil)
+	sp, err := storage.NewProvider("memory", nil)
 	if err != nil {
 		t.Fatalf("Got an unexpected error: %v", err)
 	}

server/mysql_storage_provider.go → storage/mysql/provider.go

@@ -12,7 +12,7 @@
 // See the License for the specific language governing permissions and
 // limitations under the License.
 
-package server
+package mysql
 
 import (
 	"database/sql"
@@ -22,7 +22,6 @@ import (
 	"github.com/golang/glog"
 	"github.com/google/trillian/monitoring"
 	"github.com/google/trillian/storage"
-	"github.com/google/trillian/storage/mysql"
 
 	// Load MySQL driver
 	_ "github.com/go-sql-driver/mysql"
@@ -39,8 +38,18 @@ var (
 	mysqlStorageInstance *mysqlProvider
 )
 
+// GetDatabase returns an instance of MySQL database, or creates one.
+//
+// TODO(pavelkalinnikov): Make the dependency of MySQL quota provider from
+// MySQL storage provider explicit.
+func GetDatabase() (*sql.DB, error) {
+	mysqlMu.Lock()
+	defer mysqlMu.Unlock()
+	return getMySQLDatabaseLocked()
+}
+
 func init() {
-	if err := RegisterStorageProvider("mysql", newMySQLStorageProvider); err != nil {
+	if err := storage.RegisterProvider("mysql", newMySQLStorageProvider); err != nil {
 		glog.Fatalf("Failed to register storage provider mysql: %v", err)
 	}
 }
@@ -50,7 +59,7 @@ type mysqlProvider struct {
 	mf monitoring.MetricFactory
 }
 
-func newMySQLStorageProvider(mf monitoring.MetricFactory) (StorageProvider, error) {
+func newMySQLStorageProvider(mf monitoring.MetricFactory) (storage.Provider, error) {
 	mysqlMu.Lock()
 	defer mysqlMu.Unlock()
 	if mysqlStorageInstance == nil {
@@ -66,20 +75,13 @@ func newMySQLStorageProvider(mf monitoring.MetricFactory) (StorageProvider, erro
 	return mysqlStorageInstance, nil
 }
 
-// getMySQLDatabase returns an instance of MySQL database, or creates one.
-func getMySQLDatabase() (*sql.DB, error) {
-	mysqlMu.Lock()
-	defer mysqlMu.Unlock()
-	return getMySQLDatabaseLocked()
-}
-
 // getMySQLDatabaseLocked returns an instance of MySQL database, or creates
 // one. Requires mysqlMu to be locked.
 func getMySQLDatabaseLocked() (*sql.DB, error) {
 	if mysqlDB != nil || mysqlErr != nil {
 		return mysqlDB, mysqlErr
 	}
-	db, err := mysql.OpenDB(*mySQLURI)
+	db, err := OpenDB(*mySQLURI)
 	if err != nil {
 		mysqlErr = err
 		return nil, err
@@ -95,15 +97,15 @@ func getMySQLDatabaseLocked() (*sql.DB, error) {
 }
 
 func (s *mysqlProvider) LogStorage() storage.LogStorage {
-	return mysql.NewLogStorage(s.db, s.mf)
+	return NewLogStorage(s.db, s.mf)
 }
 
 func (s *mysqlProvider) MapStorage() storage.MapStorage {
-	return mysql.NewMapStorage(s.db)
+	return NewMapStorage(s.db)
 }
 
 func (s *mysqlProvider) AdminStorage() storage.AdminStorage {
-	return mysql.NewAdminStorage(s.db)
+	return NewAdminStorage(s.db)
 }
 
 func (s *mysqlProvider) Close() error {

server/mysql_storage_provider_test.go → storage/mysql/provider_test.go

@@ -12,12 +12,13 @@
 // See the License for the specific language governing permissions and
 // limitations under the License.
 
-package server
+package mysql
 
 import (
 	"flag"
 	"testing"
 
+	"github.com/google/trillian/storage"
 	"github.com/google/trillian/testonly/flagsaver"
 )
 
@@ -28,18 +29,18 @@ func TestMySQLStorageProviderErrorPersistence(t *testing.T) {
 	}
 
 	// First call: This should fail due to the Database URL being garbage.
-	_, err1 := NewStorageProvider("mysql", nil)
+	_, err1 := storage.NewProvider("mysql", nil)
 	if err1 == nil {
-		t.Fatalf("Expected 'server.NewStorageProvider' to fail")
+		t.Fatalf("Expected 'storage.NewProvider' to fail")
 	}
 
 	// Second call: This should fail with the same error.
-	_, err2 := NewStorageProvider("mysql", nil)
+	_, err2 := storage.NewProvider("mysql", nil)
 	if err2 == nil {
-		t.Fatalf("Expected second call to 'server.NewStorageProvider' to fail")
+		t.Fatalf("Expected second call to 'storage.NewProvider' to fail")
 	}
 
 	if err2 != err1 {
-		t.Fatalf("Expected second call to 'server.NewStorageProvider' to fail with %q, instead got: %q", err1, err2)
+		t.Fatalf("Expected second call to 'storage.NewProvider' to fail with %q, instead got: %q", err1, err2)
 	}
 }