Basic service boilerplate for settings bundles

pkg/store/filesystem/store.go

@@ -0,0 +1,145 @@
+// Package store implements the go-micro store interface
+package store
+
+import (
+	"encoding/json"
+	"fmt"
+	olog "github.com/owncloud/ocis-pkg/v2/log"
+	"github.com/owncloud/ocis-settings/pkg/config"
+	"github.com/owncloud/ocis-settings/pkg/proto/v0"
+	"github.com/owncloud/ocis-settings/pkg/settings"
+	"io/ioutil"
+	"os"
+	"path"
+	"strings"
+)
+
+var (
+	// StoreName is the default name for the settings store
+	StoreName     = "ocis-settings-store"
+	managerName   = "filesystem"
+	emptyKeyError = "key cannot be empty"
+)
+
+// Store interacts with the filesystem to manage settings information
+type Store struct {
+	mountPath string
+	Logger    olog.Logger
+}
+
+// New creates a new store
+func New(cfg *config.Config) settings.Manager {
+	s := Store{}
+
+	dest := path.Join(cfg.Storage.RootMountPath, StoreName)
+	if _, err := os.Stat(dest); err != nil {
+		s.Logger.Info().Msgf("creating container on %v", dest)
+		err := os.MkdirAll(dest, 0700)
+		if err != nil {
+			s.Logger.Err(err).Msgf("providing container on %v", dest)
+		}
+	}
+
+	s.mountPath = dest
+	return &s
+}
+
+// List returns all the bundles in the mountPath folder
+func (s Store) List() ([]*proto.SettingsBundle, error) {
+	records := []*proto.SettingsBundle{}
+	bundles, err := ioutil.ReadDir(s.mountPath)
+	if err != nil {
+		s.Logger.Err(err).Msgf("error reading %v", s.mountPath)
+		return nil, err
+	}
+
+	s.Logger.Info().Msg("listing bundles")
+	for _, v := range bundles {
+		records = append(records, parseFileName(v.Name()))
+	}
+
+	return records, nil
+}
+
+// ListByExtension returns all bundles in the mountPath folder belonging to the given extension
+func (s Store) ListByExtension(extension string) ([]*proto.SettingsBundle, error) {
+	records := []*proto.SettingsBundle{}
+	bundles, err := ioutil.ReadDir(s.mountPath)
+	if err != nil {
+		s.Logger.Err(err).Msgf("error reading %v", s.mountPath)
+		return nil, err
+	}
+
+	s.Logger.Info().Msgf("listing bundles by extension %v", extension)
+	for _, v := range bundles {
+		record := parseFileName(v.Name())
+		if record.Extension == extension {
+			records = append(records, record)
+		}
+	}
+
+	return records, nil
+}
+
+// Read tries to find a bundle by the given extension and key within the mountPath
+func (s Store) Read(extension string, key string) (*proto.SettingsBundle, error) {
+	fileName := buildFileNameFromData(extension, key)
+	contents, err := ioutil.ReadFile(path.Join(s.mountPath, fileName))
+	if err != nil {
+		s.Logger.Err(err).Msgf("error reading contents for extension %v and key %v: file not found", extension, key)
+		return nil, err
+	}
+
+	record := proto.SettingsBundle{}
+	if err = json.Unmarshal(contents, &record); err != nil {
+		s.Logger.Err(err).Msg("error unmarshalling record")
+		return nil, err
+	}
+
+	return &record, nil
+}
+
+// Write writes the given record into a file within the mountPath
+func (s Store) Write(rec *proto.SettingsBundle) (*proto.SettingsBundle, error) {
+	if len(rec.Key) < 1 {
+		s.Logger.Error().Msg("key cannot be empty")
+		return nil, fmt.Errorf(emptyKeyError)
+	}
+
+	contents, err := json.Marshal(rec)
+	if err != nil {
+		s.Logger.Err(err).Msg("record could not be marshalled")
+		return nil, err
+	}
+
+	recordPath := path.Join(s.mountPath, buildFileNameFromBundle(rec))
+	if err := ioutil.WriteFile(recordPath, contents, 0644); err != nil {
+		return nil, err
+	}
+
+	s.Logger.Info().Msgf("%v bytes written to %v", len(contents), recordPath)
+	return rec, nil
+}
+
+// Builds a unique file name from the given bundle
+func buildFileNameFromBundle(bundle *proto.SettingsBundle) string {
+	return buildFileNameFromData(bundle.Extension, bundle.Key)
+}
+
+// Builds a unique file name from the given params
+func buildFileNameFromData(extension string, key string) string {
+	return extension + "__" + key + ".json"
+}
+
+// Extracts extension and key from the given fileName and builds a (minimalistic) bundle from it
+func parseFileName(fileName string) *proto.SettingsBundle {
+	parts := strings.Split(strings.Replace(fileName, ".json", "", 1), "__")
+	return &proto.SettingsBundle{
+		Key:       parts[1],
+		Extension: parts[0],
+	}
+}
+
+func init() {
+	settings.Registry[managerName] = New
+}

pkg/store/registry.go

@@ -0,0 +1,6 @@
+package store
+
+import (
+	// init filesystem store
+	_ "github.com/owncloud/ocis-settings/pkg/store/filesystem"
+)