Replace SQLite with BadgerDB

pkg/db/badger/badger.go

@@ -0,0 +1,53 @@
+package badger
+
+import (
+	"fmt"
+
+	"github.com/dgraph-io/badger/v3"
+)
+
+const (
+	// Key prefixes. Each prefix value should be unique.
+	projectPrefix = 0x00
+	reqLogPrefix  = 0x01
+	resLogPrefix  = 0x02
+
+	// Request log indices.
+	reqLogProjectIDIndex = 0x00
+)
+
+// Database is used to store and retrieve data from an underlying Badger database.
+type Database struct {
+	badger *badger.DB
+}
+
+// OpenDatabase opens a new Badger database.
+func OpenDatabase(opts badger.Options) (*Database, error) {
+	db, err := badger.Open(opts)
+	if err != nil {
+		return nil, fmt.Errorf("badger: failed to open database: %w", err)
+	}
+
+	return &Database{badger: db}, nil
+}
+
+// Close closes the underlying Badger database.
+func (db *Database) Close() error {
+	return db.badger.Close()
+}
+
+// DatabaseFromBadgerDB returns a Database with `db` set as the underlying
+// Badger database.
+func DatabaseFromBadgerDB(db *badger.DB) *Database {
+	return &Database{badger: db}
+}
+
+func entryKey(prefix, index byte, value []byte) []byte {
+	// Key consists of: | prefix (byte) | index (byte) | value
+	key := make([]byte, 2+len(value))
+	key[0] = prefix
+	key[1] = index
+	copy(key[2:len(value)+2], value)
+
+	return key
+}