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// This Source Code Form is subject to the terms of the Mozilla Public
// License, v. 2.0. If a copy of the MPL was not distributed with this
// file, You can obtain one at http://mozilla.org/MPL/2.0/.
package cache
import (
"database/sql"
"fmt"
"log"
"os"
_ "github.com/mattn/go-sqlite3"
)
func NewSQLiteStore(file string) *SQLiteStore {
db, err := sql.Open("sqlite3", fmt.Sprintf("file:%s?_timeout=5000&_journal=WAL", file))
if err != nil {
log.Printf("cache: failed to create database file %q: %v\n", file, err)
os.Exit(1)
}
c := &SQLiteStore{db: db}
c.migrate()
return c
}
type SQLiteStore struct {
db *sql.DB
}
func (s *SQLiteStore) Get(key string) ([]byte, bool) {
var value []byte
if err := s.db.QueryRow(`SELECT value FROM cache WHERE key = ? LIMIT 1`, key).Scan(&value); err != nil {
return nil, false
}
return value, true
}
func (s *SQLiteStore) Set(key string, value []byte) {
if _, err := s.db.Exec(`INSERT INTO cache (key, value) VALUES (?, ?)`, key, value); err != nil {
log.Printf("cache: failed to insert cache key %q: %v\n", key, value)
}
}
func (s *SQLiteStore) Close() {
s.db.Close()
}
func (s *SQLiteStore) migrate() {
if _, err := s.db.Exec(`CREATE TABLE IF NOT EXISTS cache (key TEXT, value BLOB)`); err != nil {
log.Printf("cache: failed to create cache table: %v\n", err)
os.Exit(1)
}
if _, err := s.db.Exec(`CREATE UNIQUE INDEX IF NOT EXISTS cache_key_idx ON cache(key)`); err != nil {
log.Printf("cache: failed to create cache index: %v\n", err)
os.Exit(1)
}
}
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