Add filter storage method

Also remove de/encryption in cloud storage, can be provided with a
filter storage

2 files changed, 47 insertions, 5 deletions

diff --git a/storage/registry/filter_conf.go b/storage/registry/filter_conf.go
new file mode 100644
index 0000000..593f238
--- /dev/null
+++ b/storage/registry/filter_conf.go
@@ -0,0 +1,39 @@
+package registry
+
+import (
+	"code.laria.me/petrific/config"
+	"code.laria.me/petrific/storage"
+	"code.laria.me/petrific/storage/filter"
+)
+
+// Unlike the other storage engines, we can not define FilterStorages
+// *FromConfig function in the package itself, because we need to reference the
+// registry package and circular imports are not allowed
+
+func filterStorageFromConfig(conf config.Config, name string) (storage.Storage, error) {
+	var storage_conf struct {
+		Base   string
+		Encode []string
+		Decode []string
+	}
+
+	if err := conf.GetStorageConfData(name, &storage_conf); err != nil {
+		return nil, err
+	}
+
+	base, err := LoadStorage(conf, storage_conf.Base)
+	if err != nil {
+		return nil, err
+	}
+
+	st := filter.FilterStorage{Base: base}
+
+	if len(storage_conf.Encode) > 0 {
+		st.Encode = filter.PipeFilter(storage_conf.Encode)
+	}
+	if len(storage_conf.Decode) > 0 {
+		st.Decode = filter.PipeFilter(storage_conf.Decode)
+	}
+
+	return st, nil
+}
diff --git a/storage/registry/registry.go b/storage/registry/registry.go
index f792946..4b48ef4 100644
--- a/storage/registry/registry.go
+++ b/storage/registry/registry.go
@@ -11,10 +11,13 @@ import (
 )
 
 // List af all available storage types
-var StorageTypes = map[string]storage.CreateStorageFromConfig{
-	"local":           local.LocalStorageFromConfig,
-	"memory":          memory.MemoryStorageFromConfig,
-	"openstack-swift": cloud.SwiftStorageCreator(),
+func getStorageTypes() map[string]storage.CreateStorageFromConfig {
+	return map[string]storage.CreateStorageFromConfig{
+		"local":           local.LocalStorageFromConfig,
+		"memory":          memory.MemoryStorageFromConfig,
+		"filter":          filterStorageFromConfig,
+		"openstack-swift": cloud.SwiftStorageCreator(),
+	}
 }
 
 var notFoundErr = errors.New("Storage not found")
@@ -41,7 +44,7 @@ func loadStorage(conf config.Config, storageName string) (storage.Storage, error
 		return nil, err
 	}
 
-	st, ok := StorageTypes[method]
+	st, ok := getStorageTypes()[method]
 	if !ok {
 		return nil, unknownMethodErr(method)
 	}