Limit to only 1 ttl database write when storing data on storage nodes (#348)

* Limit to only 1 database write

* Check file system rather than database

* Move check to storefile. We need to figure out how to fix this mess

* piecestore should not overwrite data, it should fail when trying to write to a file that already exists

* Format errors, delete unused function in psdb for checking if TTL exists

* Combine errors better

pkg/piecestore/pstore.go

@@ -56,7 +56,7 @@ func StoreWriter(id string, dir string) (io.WriteCloser, error) {
 	}
 
 	// Create File on file system
-	return os.OpenFile(dataPath, os.O_RDWR|os.O_CREATE, 0755)
+	return os.OpenFile(dataPath, os.O_CREATE|os.O_EXCL|os.O_WRONLY, 0755)
 }
 
 // RetrieveReader retrieves data from pstore directory

pkg/piecestore/rpc/server/psdb/psdb.go

@@ -201,20 +201,12 @@ func (db *DB) GetBandwidthAllocationBySignature(signature []byte) ([][]byte, err
 	return agreements, nil
 }
 
-// AddTTLToDB adds TTL into database by id
-func (db *DB) AddTTLToDB(id string, expiration int64) error {
+// AddTTL adds TTL into database by id
+func (db *DB) AddTTL(id string, expiration, size int64) error {
 	defer db.locked()()
 
 	created := time.Now().Unix()
-	_, err := db.DB.Exec("INSERT or REPLACE INTO ttl (id, created, expires) VALUES (?, ?, ?)", id, created, expiration)
-	return err
-}
-
-// UpdateTTLSize adds stored data size into database by id
-func (db *DB) UpdateTTLSize(id string, size int64) error {
-	defer db.locked()()
-
-	_, err := db.DB.Exec("UPDATE ttl SET size=? WHERE id=?", size, id)
+	_, err := db.DB.Exec("INSERT OR REPLACE INTO ttl (id, created, expires, size) VALUES (?, ?, ?, ?)", id, created, expiration, size)
 	return err
 }
 

pkg/piecestore/rpc/server/psdb/psdb_test.go

@@ -67,7 +67,7 @@ func TestHappyPath(t *testing.T) {
 			t.Run("#"+strconv.Itoa(P), func(t *testing.T) {
 				t.Parallel()
 				for _, ttl := range tests {
-					err := db.AddTTLToDB(ttl.ID, ttl.Expiration)
+					err := db.AddTTL(ttl.ID, ttl.Expiration, 0)
 					if err != nil {
 						t.Fatal(err)
 					}

pkg/piecestore/rpc/server/store.go

@@ -44,19 +44,14 @@ func (s *Server) Store(reqStream pb.PieceStoreRoutes_StoreServer) (err error) {
 		return StoreError.New("Piece ID not specified")
 	}
 
-	// If we put in the database first then that checks if the data already exists
-	if err = s.DB.AddTTLToDB(pd.GetId(), pd.GetExpirationUnixSec()); err != nil {
-		return StoreError.New("Failed to write expiration data to database")
-	}
-
 	total, err := s.storeData(ctx, reqStream, pd.GetId())
 	if err != nil {
 		return err
 	}
 
-	// If we put in the database first then that checks if the data already exists
-	if err = s.DB.UpdateTTLSize(pd.GetId(), total); err != nil {
-		return StoreError.New("Failed to write total data to ttl database")
+	if err = s.DB.AddTTL(pd.GetId(), pd.GetExpirationUnixSec(), total); err != nil {
+		deleteErr := s.deleteByID(pd.GetId())
+		return StoreError.New("failed to write piece meta data to database: %v", utils.CombineErrors(err, deleteErr))
 	}
 
 	log.Printf("Successfully stored %s.", pd.GetId())