chore: refactor blob storage factory (#55)

Consistent factory style. #44 #45

internal/storage/blobstorage/internal/blobstorage.go

@@ -4,7 +4,9 @@ import (
 	"context"
 
 	"go.uber.org/fx"
+	"golang.org/x/xerrors"
 
+	"github.com/coinbase/chainstorage/internal/config"
 	"github.com/coinbase/chainstorage/internal/utils/fxparams"
 	api "github.com/coinbase/chainstorage/protos/coinbase/chainstorage"
 )
@@ -25,3 +27,20 @@ type (
 		S3 BlobStorageFactory `name:"blobstorage/s3"`
 	}
 )
+
+func WithBlobStorageFactory(params BlobStorageFactoryParams) (BlobStorage, error) {
+	var factory BlobStorageFactory
+	storageType := params.Config.StorageType.BlobStorageType
+	switch storageType {
+	case config.BlobStorageType_UNSPECIFIED, config.BlobStorageType_S3:
+		factory = params.S3
+	}
+	if factory == nil {
+		return nil, xerrors.Errorf("blob storage type is not implemented: %v", storageType)
+	}
+	result, err := factory.Create()
+	if err != nil {
+		return nil, xerrors.Errorf("failed to create blob storage of type %v: %w", storageType, err)
+	}
+	return result, nil
+}

internal/storage/blobstorage/module.go

@@ -3,12 +3,17 @@ package blobstorage
 import (
 	"go.uber.org/fx"
 
-	"github.com/coinbase/chainstorage/internal/storage/blobstorage/downloader"
+	"github.com/coinbase/chainstorage/internal/storage/blobstorage/internal"
 	"github.com/coinbase/chainstorage/internal/storage/blobstorage/s3"
 )
 
+type (
+	BlobStorage              = internal.BlobStorage
+	BlobStorageFactory       = internal.BlobStorageFactory
+	BlobStorageFactoryParams = internal.BlobStorageFactoryParams
+)
+
 var Module = fx.Options(
-	fx.Provide(New),
+	fx.Provide(internal.WithBlobStorageFactory),
 	s3.Module,
-	downloader.Module,
 )