Implement Persentance with SQLite3 (#6)

persistence/database.go

@@ -0,0 +1,6 @@
+package persistence
+
+type Database interface {
+	GetDiscordMessage(id string) (string, error)
+	SetDiscordMessage(id string, messageID string) error
+}

persistence/sql/20230401-initial-schema.sql

@@ -0,0 +1,8 @@
+-- +migrate Up
+CREATE TABLE IF NOT EXISTS discord_messages (
+    id TEXT NOT NULL PRIMARY KEY,
+    message_id TEXT NOT NULL
+);
+
+-- +migrate Down
+DROP TABLE discord_messages;

persistence/sqlite3.go

@@ -0,0 +1,104 @@
+package persistence
+
+import (
+	"database/sql"
+	"embed"
+	"fmt"
+	"log"
+
+	_ "github.com/mattn/go-sqlite3"
+	migrate "github.com/rubenv/sql-migrate"
+)
+
+//go:embed sql/*
+var migrationScripts embed.FS
+
+type Sqlite3Database struct {
+	db *sql.DB
+}
+
+func NewSqlite3Database() *Sqlite3Database {
+	db, err := sql.Open("sqlite3", "./birdbot.db")
+	if err != nil {
+		log.Printf("failed to open db: %s", err)
+		return nil
+	}
+
+	return &Sqlite3Database{
+		db: db,
+	}
+}
+
+func getMigrations() migrate.MigrationSource {
+	return &migrate.EmbedFileSystemMigrationSource{
+		FileSystem: migrationScripts,
+		Root:       "sql",
+	}
+}
+
+func (db *Sqlite3Database) MigrateUp() error {
+
+	n, err := migrate.Exec(db.db, "sqlite3", getMigrations(), migrate.Up)
+	if err != nil {
+		return fmt.Errorf("failed to migrate: %s", err)
+	}
+
+	if n != 0 {
+		log.Printf("Applied %d DB migrations!\n", n)
+	}
+	return nil
+}
+
+func (db *Sqlite3Database) MigrateDown() error {
+
+	n, err := migrate.Exec(db.db, "sqlite3", getMigrations(), migrate.Down)
+	if err != nil {
+		return fmt.Errorf("failed to migrate: %s", err)
+	}
+
+	if n != 0 {
+		log.Printf("Applied %d DB migrations!\n", n)
+	}
+	return nil
+}
+
+func (db *Sqlite3Database) GetDiscordMessage(id string) (string, error) {
+
+	var messageID string
+	row := db.db.QueryRow("SELECT message_id FROM discord_messages WHERE id = $1", id)
+
+	if err := row.Scan(&messageID); err != nil {
+		return "", fmt.Errorf("failed to get discord message from sqlite3: %s", err)
+	}
+
+	return messageID, nil
+}
+
+func (db *Sqlite3Database) SetDiscordMessage(id string, messageID string) error {
+
+	statement, err := db.db.Prepare("INSERT OR IGNORE INTO discord_messages (id, message_id) VALUES (?, ?)")
+	if err != nil {
+		return err
+	}
+
+	result, err := statement.Exec(id, messageID)
+	if err != nil {
+		return err
+	}
+
+	n, _ := result.RowsAffected()
+
+	if n == 0 {
+		statement, err := db.db.Prepare("UPDATE discord_messages SET message_id = (?) WHERE id = (?)")
+		if err != nil {
+			return err
+		}
+
+		if _, err := statement.Exec(messageID, id); err != nil {
+			return err
+		}
+
+	}
+
+	return nil
+}