do not make noise if entries are already in the database

pkg/cache/cache.go

@@ -506,7 +506,9 @@ func (c *Cache) putNarInfoInStore(hash string, narInfo *narinfo.NarInfo) error {
 }
 
 func (c *Cache) storeInDatabase(hash string, narInfo *narinfo.NarInfo) error {
-	c.logger.Info("storing narinfo and nar record in the database", "hash", hash, "nar-url", narInfo.URL)
+	log := c.logger.New("hash", hash, "nar-url", narInfo.URL)
+
+	log.Info("storing narinfo and nar record in the database")
 
 	tx, err := c.db.Begin()
 	if err != nil {
@@ -523,6 +525,11 @@ func (c *Cache) storeInDatabase(hash string, narInfo *narinfo.NarInfo) error {
 
 	res, err := c.db.InsertNarInfoRecord(tx, hash)
 	if err != nil {
+		if errors.Is(err, database.ErrAlreadyExists) {
+			log.Warn("narinfo record was not added to database because it already exists")
+			return nil
+		}
+
 		return fmt.Errorf("error inserting the narinfo record for hash %q in the database: %w", hash, err)
 	}
 
@@ -537,6 +544,11 @@ func (c *Cache) storeInDatabase(hash string, narInfo *narinfo.NarInfo) error {
 	}
 
 	if _, err := c.db.InsertNarRecord(tx, lid, narHash, compression, narInfo.FileSize); err != nil {
+		if errors.Is(err, database.ErrAlreadyExists) {
+			log.Warn("nar record was not added to database because it already exists")
+			return nil
+		}
+
 		return fmt.Errorf("error inserting the nar record in the database: %w", err)
 	}
 

pkg/database/sqlite.go

@@ -9,6 +9,7 @@ import (
 	"github.com/inconshreveable/log15/v3"
 
 	// Import the SQLite driver.
+	"github.com/mattn/go-sqlite3"
 	_ "github.com/mattn/go-sqlite3"
 )
 
@@ -77,6 +78,9 @@ const (
 var (
 	// ErrNotFound is returned if record is not found in the database.
 	ErrNotFound = errors.New("not found")
+
+	// ErrAlreadyExists is returned if record insertion failed due to uniqueness constraint.
+	ErrAlreadyExists = errors.New("error already exists")
 )
 
 type (
@@ -178,6 +182,11 @@ func (db *DB) InsertNarInfoRecord(tx *sql.Tx, hash string) (sql.Result, error) {
 
 	res, err := stmt.Exec(hash)
 	if err != nil {
+		sqliteErr, ok := errors.Unwrap(err).(sqlite3.Error)
+		if ok && sqliteErr.Code == sqlite3.ErrConstraint {
+			return nil, ErrAlreadyExists
+		}
+
 		return nil, fmt.Errorf("error executing the statement: %w", err)
 	}
 
@@ -250,6 +259,11 @@ func (db *DB) InsertNarRecord(tx *sql.Tx, narInfoID int64,
 
 	res, err := stmt.Exec(narInfoID, hash, compression, fileSize)
 	if err != nil {
+		sqliteErr, ok := errors.Unwrap(err).(sqlite3.Error)
+		if ok && sqliteErr.Code == sqlite3.ErrConstraint {
+			return nil, ErrAlreadyExists
+		}
+
 		return nil, fmt.Errorf("error executing the statement: %w", err)
 	}