Initial QSfera import

Server/services/settings/pkg/store/metadata/cache.go

@@ -0,0 +1,170 @@
+package store
+
+import (
+	"context"
+	"path"
+
+	olog "github.com/qsfera/server/pkg/log"
+	"github.com/qsfera/server/services/settings/pkg/config"
+	"github.com/opencloud-eu/reva/v2/pkg/store"
+	"github.com/vmihailenco/msgpack/v5"
+	microstore "go-micro.dev/v4/store"
+)
+
+// CachedMDC is cache for the metadataclient
+type CachedMDC struct {
+	cfg    *config.Config
+	logger olog.Logger
+	next   MetadataClient
+
+	filesCache microstore.Store
+	dirsCache  microstore.Store
+}
+
+// SimpleDownload caches the answer from SimpleDownload or returns the cached one
+func (c *CachedMDC) SimpleDownload(ctx context.Context, id string) ([]byte, error) {
+	if b, err := c.filesCache.Read(id); err == nil && len(b) == 1 {
+		return b[0].Value, nil
+	}
+	b, err := c.next.SimpleDownload(ctx, id)
+	if err != nil {
+		return nil, err
+	}
+
+	err = c.filesCache.Write(&microstore.Record{
+		Key:    id,
+		Value:  b,
+		Expiry: c.cfg.Metadata.Cache.TTL,
+	})
+	if err != nil {
+		c.logger.Error().Err(err).Msg("SimpleDownload: failed to update to files cache")
+	}
+	return b, nil
+}
+
+// SimpleUpload caches the answer from SimpleUpload and invalidates the cache
+func (c *CachedMDC) SimpleUpload(ctx context.Context, id string, content []byte) error {
+	b, err := c.filesCache.Read(id)
+	if err == nil && len(b) == 1 && string(b[0].Value) == string(content) {
+		// no need to bug mdc
+		return nil
+	}
+
+	err = c.next.SimpleUpload(ctx, id, content)
+	if err != nil {
+		return err
+	}
+
+	// invalidate caches
+	if err = c.dirsCache.Delete(path.Dir(id)); err != nil {
+		c.logger.Error().Err(err).Msg("failed to clear dirs cache")
+	}
+
+	err = c.filesCache.Write(&microstore.Record{
+		Key:    id,
+		Value:  content,
+		Expiry: c.cfg.Metadata.Cache.TTL,
+	})
+	if err != nil {
+		c.logger.Error().Err(err).Msg("SimpleUpload: failed to update to files cache")
+	}
+	return nil
+}
+
+// Delete invalidates the cache when operation was successful
+func (c *CachedMDC) Delete(ctx context.Context, id string) error {
+	if err := c.next.Delete(ctx, id); err != nil {
+		return err
+	}
+
+	// invalidate caches
+	_ = c.removePrefix(c.filesCache, id)
+	_ = c.removePrefix(c.dirsCache, id)
+	return nil
+}
+
+// ReadDir caches the response from ReadDir or returnes the cached one
+func (c *CachedMDC) ReadDir(ctx context.Context, id string) ([]string, error) {
+	i, err := c.dirsCache.Read(id)
+	if err == nil && len(i) == 1 {
+		var ret []string
+		if err = msgpack.Unmarshal(i[0].Value, &ret); err == nil {
+			return ret, nil
+		}
+		c.logger.Error().Err(err).Msg("failed to unmarshal entry from dirs cache")
+	}
+
+	s, err := c.next.ReadDir(ctx, id)
+	if err != nil {
+		return nil, err
+	}
+
+	var value []byte
+	if value, err = msgpack.Marshal(s); err != nil {
+		c.logger.Error().Err(err).Msg("failed to marshal ReadDir result for dirs cache")
+		return s, err
+	}
+	err = c.dirsCache.Write(&microstore.Record{
+		Key:    id,
+		Value:  value,
+		Expiry: c.cfg.Metadata.Cache.TTL,
+	})
+	if err != nil {
+		c.logger.Error().Err(err).Msg("ReadDir: failed to update dirs cache")
+	}
+
+	return s, err
+}
+
+// MakeDirIfNotExist invalidates the cache
+func (c *CachedMDC) MakeDirIfNotExist(ctx context.Context, id string) error {
+	err := c.next.MakeDirIfNotExist(ctx, id)
+	if err != nil {
+		return err
+	}
+
+	// invalidate caches
+	if err = c.dirsCache.Delete(path.Dir(id)); err != nil {
+		c.logger.Error().Err(err).Msg("failed to clear dirs cache")
+	}
+	return nil
+}
+
+// Init instantiates the caches
+func (c *CachedMDC) Init(ctx context.Context, id string) error {
+	c.dirsCache = store.Create(
+		store.Store(c.cfg.Metadata.Cache.Store),
+		store.TTL(c.cfg.Metadata.Cache.TTL),
+		microstore.Nodes(c.cfg.Metadata.Cache.Nodes...),
+		microstore.Database(c.cfg.Metadata.Cache.Database),
+		microstore.Table(c.cfg.Metadata.Cache.DirectoryTable),
+		store.DisablePersistence(c.cfg.Metadata.Cache.DisablePersistence),
+		store.Authentication(c.cfg.Metadata.Cache.AuthUsername, c.cfg.Metadata.Cache.AuthPassword),
+	)
+	c.filesCache = store.Create(
+		store.Store(c.cfg.Metadata.Cache.Store),
+		store.TTL(c.cfg.Metadata.Cache.TTL),
+		microstore.Nodes(c.cfg.Metadata.Cache.Nodes...),
+		microstore.Database(c.cfg.Metadata.Cache.Database),
+		microstore.Table(c.cfg.Metadata.Cache.FileTable),
+		store.DisablePersistence(c.cfg.Metadata.Cache.DisablePersistence),
+		store.Authentication(c.cfg.Metadata.Cache.AuthUsername, c.cfg.Metadata.Cache.AuthPassword),
+	)
+	return c.next.Init(ctx, id)
+}
+
+func (c *CachedMDC) removePrefix(cache microstore.Store, prefix string) error {
+	c.logger.Debug().Str("prefix", prefix).Msg("removePrefix")
+	keys, err := cache.List(microstore.ListPrefix(prefix))
+	if err != nil {
+		c.logger.Error().Err(err).Msg("failed to list cache entries")
+	}
+	for _, k := range keys {
+		c.logger.Debug().Str("key", k).Msg("removePrefix")
+		if err := cache.Delete(k); err != nil {
+			c.logger.Error().Err(err).Msg("failed to remove prefix from cache")
+			return err
+		}
+	}
+	return nil
+}