db: refactor into interface

This refactors the SQLite-specific bits into db_sqlite.go. A future
patch will add PostgreSQL support.

cmd/soju/main.go

@@ -61,7 +61,7 @@ func main() {
 		cfg.Listen = []string{":6697"}
 	}
 
-	db, err := soju.OpenSQLDB(cfg.SQLDriver, cfg.SQLSource)
+	db, err := soju.OpenSqliteDB(cfg.SQLDriver, cfg.SQLSource)
 	if err != nil {
 		log.Fatalf("failed to open database: %v", err)
 	}

cmd/sojuctl/main.go

@@ -43,7 +43,7 @@ func main() {
 		cfg = config.Defaults()
 	}
 
-	db, err := soju.OpenSQLDB(cfg.SQLDriver, cfg.SQLSource)
+	db, err := soju.OpenSqliteDB(cfg.SQLDriver, cfg.SQLSource)
 	if err != nil {
 		log.Fatalf("failed to open database: %v", err)
 	}

contrib/znc-import.go

@@ -61,7 +61,7 @@ func main() {
 		cfg = config.Defaults()
 	}
 
-	db, err := soju.OpenSQLDB(cfg.SQLDriver, cfg.SQLSource)
+	db, err := soju.OpenSqliteDB(cfg.SQLDriver, cfg.SQLSource)
 	if err != nil {
 		log.Fatalf("failed to open database: %v", err)
 	}

db.go

@@ -1,17 +1,31 @@
 package soju
 
 import (
-	"database/sql"
 	"fmt"
-	"math"
 	"net/url"
 	"strings"
-	"sync"
 	"time"
-
-	_ "github.com/mattn/go-sqlite3"
 )
 
+type Database interface {
+	Close() error
+
+	ListUsers() ([]User, error)
+	GetUser(username string) (*User, error)
+	StoreUser(user *User) error
+	DeleteUser(id int64) error
+
+	ListNetworks(userID int64) ([]Network, error)
+	StoreNetwork(userID int64, network *Network) error
+	DeleteNetwork(id int64) error
+	ListChannels(networkID int64) ([]Channel, error)
+	StoreChannel(networKID int64, ch *Channel) error
+	DeleteChannel(id int64) error
+
+	ListDeliveryReceipts(networkID int64) ([]DeliveryReceipt, error)
+	StoreClientDeliveryReceipts(networkID int64, client string, receipts []DeliveryReceipt) error
+}
+
 type User struct {
 	ID       int64
 	Username string
@@ -128,550 +142,3 @@ type DeliveryReceipt struct {
 	Client        string
 	InternalMsgID string
 }
-
-const schema = `
-CREATE TABLE User (
-	id INTEGER PRIMARY KEY,
-	username VARCHAR(255) NOT NULL UNIQUE,
-	password VARCHAR(255),
-	admin INTEGER NOT NULL DEFAULT 0
-);
-
-CREATE TABLE Network (
-	id INTEGER PRIMARY KEY,
-	name VARCHAR(255),
-	user INTEGER NOT NULL,
-	addr VARCHAR(255) NOT NULL,
-	nick VARCHAR(255) NOT NULL,
-	username VARCHAR(255),
-	realname VARCHAR(255),
-	pass VARCHAR(255),
-	connect_commands VARCHAR(1023),
-	sasl_mechanism VARCHAR(255),
-	sasl_plain_username VARCHAR(255),
-	sasl_plain_password VARCHAR(255),
-	sasl_external_cert BLOB DEFAULT NULL,
-	sasl_external_key BLOB DEFAULT NULL,
-	FOREIGN KEY(user) REFERENCES User(id),
-	UNIQUE(user, addr, nick),
-	UNIQUE(user, name)
-);
-
-CREATE TABLE Channel (
-	id INTEGER PRIMARY KEY,
-	network INTEGER NOT NULL,
-	name VARCHAR(255) NOT NULL,
-	key VARCHAR(255),
-	detached INTEGER NOT NULL DEFAULT 0,
-	detached_internal_msgid VARCHAR(255),
-	relay_detached INTEGER NOT NULL DEFAULT 0,
-	reattach_on INTEGER NOT NULL DEFAULT 0,
-	detach_after INTEGER NOT NULL DEFAULT 0,
-	detach_on INTEGER NOT NULL DEFAULT 0,
-	FOREIGN KEY(network) REFERENCES Network(id),
-	UNIQUE(network, name)
-);
-
-CREATE TABLE DeliveryReceipt (
-	id INTEGER PRIMARY KEY,
-	network INTEGER NOT NULL,
-	target VARCHAR(255) NOT NULL,
-	client VARCHAR(255),
-	internal_msgid VARCHAR(255) NOT NULL,
-	FOREIGN KEY(network) REFERENCES Network(id),
-	UNIQUE(network, target, client)
-);
-`
-
-var migrations = []string{
-	"", // migration #0 is reserved for schema initialization
-	"ALTER TABLE Network ADD COLUMN connect_commands VARCHAR(1023)",
-	"ALTER TABLE Channel ADD COLUMN detached INTEGER NOT NULL DEFAULT 0",
-	"ALTER TABLE Network ADD COLUMN sasl_external_cert BLOB DEFAULT NULL",
-	"ALTER TABLE Network ADD COLUMN sasl_external_key BLOB DEFAULT NULL",
-	"ALTER TABLE User ADD COLUMN admin INTEGER NOT NULL DEFAULT 0",
-	`
-		CREATE TABLE UserNew (
-			id INTEGER PRIMARY KEY,
-			username VARCHAR(255) NOT NULL UNIQUE,
-			password VARCHAR(255),
-			admin INTEGER NOT NULL DEFAULT 0
-		);
-		INSERT INTO UserNew SELECT rowid, username, password, admin FROM User;
-		DROP TABLE User;
-		ALTER TABLE UserNew RENAME TO User;
-	`,
-	`
-		CREATE TABLE NetworkNew (
-			id INTEGER PRIMARY KEY,
-			name VARCHAR(255),
-			user INTEGER NOT NULL,
-			addr VARCHAR(255) NOT NULL,
-			nick VARCHAR(255) NOT NULL,
-			username VARCHAR(255),
-			realname VARCHAR(255),
-			pass VARCHAR(255),
-			connect_commands VARCHAR(1023),
-			sasl_mechanism VARCHAR(255),
-			sasl_plain_username VARCHAR(255),
-			sasl_plain_password VARCHAR(255),
-			sasl_external_cert BLOB DEFAULT NULL,
-			sasl_external_key BLOB DEFAULT NULL,
-			FOREIGN KEY(user) REFERENCES User(id),
-			UNIQUE(user, addr, nick),
-			UNIQUE(user, name)
-		);
-		INSERT INTO NetworkNew
-			SELECT Network.id, name, User.id as user, addr, nick,
-				Network.username, realname, pass, connect_commands,
-				sasl_mechanism, sasl_plain_username, sasl_plain_password,
-				sasl_external_cert, sasl_external_key
-			FROM Network
-			JOIN User ON Network.user = User.username;
-		DROP TABLE Network;
-		ALTER TABLE NetworkNew RENAME TO Network;
-	`,
-	`
-		ALTER TABLE Channel ADD COLUMN relay_detached INTEGER NOT NULL DEFAULT 0;
-		ALTER TABLE Channel ADD COLUMN reattach_on INTEGER NOT NULL DEFAULT 0;
-		ALTER TABLE Channel ADD COLUMN detach_after INTEGER NOT NULL DEFAULT 0;
-		ALTER TABLE Channel ADD COLUMN detach_on INTEGER NOT NULL DEFAULT 0;
-	`,
-	`
-		CREATE TABLE DeliveryReceipt (
-			id INTEGER PRIMARY KEY,
-			network INTEGER NOT NULL,
-			target VARCHAR(255) NOT NULL,
-			client VARCHAR(255),
-			internal_msgid VARCHAR(255) NOT NULL,
-			FOREIGN KEY(network) REFERENCES Network(id),
-			UNIQUE(network, target, client)
-		);
-	`,
-	"ALTER TABLE Channel ADD COLUMN detached_internal_msgid VARCHAR(255)",
-}
-
-type DB struct {
-	lock sync.RWMutex
-	db   *sql.DB
-}
-
-func OpenSQLDB(driver, source string) (*DB, error) {
-	sqlDB, err := sql.Open(driver, source)
-	if err != nil {
-		return nil, err
-	}
-
-	db := &DB{db: sqlDB}
-	if err := db.upgrade(); err != nil {
-		return nil, err
-	}
-
-	return db, nil
-}
-
-func (db *DB) Close() error {
-	db.lock.Lock()
-	defer db.lock.Unlock()
-	return db.db.Close()
-}
-
-func (db *DB) upgrade() error {
-	db.lock.Lock()
-	defer db.lock.Unlock()
-
-	var version int
-	if err := db.db.QueryRow("PRAGMA user_version").Scan(&version); err != nil {
-		return fmt.Errorf("failed to query schema version: %v", err)
-	}
-
-	if version == len(migrations) {
-		return nil
-	} else if version > len(migrations) {
-		return fmt.Errorf("soju (version %d) older than schema (version %d)", len(migrations), version)
-	}
-
-	tx, err := db.db.Begin()
-	if err != nil {
-		return err
-	}
-	defer tx.Rollback()
-
-	if version == 0 {
-		if _, err := tx.Exec(schema); err != nil {
-			return fmt.Errorf("failed to initialize schema: %v", err)
-		}
-	} else {
-		for i := version; i < len(migrations); i++ {
-			if _, err := tx.Exec(migrations[i]); err != nil {
-				return fmt.Errorf("failed to execute migration #%v: %v", i, err)
-			}
-		}
-	}
-
-	// For some reason prepared statements don't work here
-	_, err = tx.Exec(fmt.Sprintf("PRAGMA user_version = %d", len(migrations)))
-	if err != nil {
-		return fmt.Errorf("failed to bump schema version: %v", err)
-	}
-
-	return tx.Commit()
-}
-
-func toNullString(s string) sql.NullString {
-	return sql.NullString{
-		String: s,
-		Valid:  s != "",
-	}
-}
-
-func (db *DB) ListUsers() ([]User, error) {
-	db.lock.RLock()
-	defer db.lock.RUnlock()
-
-	rows, err := db.db.Query("SELECT id, username, password, admin FROM User")
-	if err != nil {
-		return nil, err
-	}
-	defer rows.Close()
-
-	var users []User
-	for rows.Next() {
-		var user User
-		var password sql.NullString
-		if err := rows.Scan(&user.ID, &user.Username, &password, &user.Admin); err != nil {
-			return nil, err
-		}
-		user.Password = password.String
-		users = append(users, user)
-	}
-	if err := rows.Err(); err != nil {
-		return nil, err
-	}
-
-	return users, nil
-}
-
-func (db *DB) GetUser(username string) (*User, error) {
-	db.lock.RLock()
-	defer db.lock.RUnlock()
-
-	user := &User{Username: username}
-
-	var password sql.NullString
-	row := db.db.QueryRow("SELECT id, password, admin FROM User WHERE username = ?", username)
-	if err := row.Scan(&user.ID, &password, &user.Admin); err != nil {
-		return nil, err
-	}
-	user.Password = password.String
-	return user, nil
-}
-
-func (db *DB) StoreUser(user *User) error {
-	db.lock.Lock()
-	defer db.lock.Unlock()
-
-	password := toNullString(user.Password)
-
-	var err error
-	if user.ID != 0 {
-		_, err = db.db.Exec("UPDATE User SET password = ?, admin = ? WHERE username = ?",
-			password, user.Admin, user.Username)
-	} else {
-		var res sql.Result
-		res, err = db.db.Exec("INSERT INTO User(username, password, admin) VALUES (?, ?, ?)",
-			user.Username, password, user.Admin)
-		if err != nil {
-			return err
-		}
-		user.ID, err = res.LastInsertId()
-	}
-
-	return err
-}
-
-func (db *DB) DeleteUser(id int64) error {
-	db.lock.Lock()
-	defer db.lock.Unlock()
-
-	tx, err := db.db.Begin()
-	if err != nil {
-		return err
-	}
-	defer tx.Rollback()
-
-	_, err = tx.Exec(`DELETE FROM Channel
-		WHERE id IN (
-			SELECT Channel.id
-			FROM Channel
-			JOIN Network ON Channel.network = Network.id
-			WHERE Network.user = ?
-		)`, id)
-	if err != nil {
-		return err
-	}
-
-	_, err = tx.Exec("DELETE FROM Network WHERE user = ?", id)
-	if err != nil {
-		return err
-	}
-
-	_, err = tx.Exec("DELETE FROM User WHERE id = ?", id)
-	if err != nil {
-		return err
-	}
-
-	return tx.Commit()
-}
-
-func (db *DB) ListNetworks(userID int64) ([]Network, error) {
-	db.lock.RLock()
-	defer db.lock.RUnlock()
-
-	rows, err := db.db.Query(`SELECT id, name, addr, nick, username, realname, pass,
-			connect_commands, sasl_mechanism, sasl_plain_username, sasl_plain_password,
-			sasl_external_cert, sasl_external_key
-		FROM Network
-		WHERE user = ?`,
-		userID)
-	if err != nil {
-		return nil, err
-	}
-	defer rows.Close()
-
-	var networks []Network
-	for rows.Next() {
-		var net Network
-		var name, username, realname, pass, connectCommands sql.NullString
-		var saslMechanism, saslPlainUsername, saslPlainPassword sql.NullString
-		err := rows.Scan(&net.ID, &name, &net.Addr, &net.Nick, &username, &realname,
-			&pass, &connectCommands, &saslMechanism, &saslPlainUsername, &saslPlainPassword,
-			&net.SASL.External.CertBlob, &net.SASL.External.PrivKeyBlob)
-		if err != nil {
-			return nil, err
-		}
-		net.Name = name.String
-		net.Username = username.String
-		net.Realname = realname.String
-		net.Pass = pass.String
-		if connectCommands.Valid {
-			net.ConnectCommands = strings.Split(connectCommands.String, "\r\n")
-		}
-		net.SASL.Mechanism = saslMechanism.String
-		net.SASL.Plain.Username = saslPlainUsername.String
-		net.SASL.Plain.Password = saslPlainPassword.String
-		networks = append(networks, net)
-	}
-	if err := rows.Err(); err != nil {
-		return nil, err
-	}
-
-	return networks, nil
-}
-
-func (db *DB) StoreNetwork(userID int64, network *Network) error {
-	db.lock.Lock()
-	defer db.lock.Unlock()
-
-	netName := toNullString(network.Name)
-	netUsername := toNullString(network.Username)
-	realname := toNullString(network.Realname)
-	pass := toNullString(network.Pass)
-	connectCommands := toNullString(strings.Join(network.ConnectCommands, "\r\n"))
-
-	var saslMechanism, saslPlainUsername, saslPlainPassword sql.NullString
-	if network.SASL.Mechanism != "" {
-		saslMechanism = toNullString(network.SASL.Mechanism)
-		switch network.SASL.Mechanism {
-		case "PLAIN":
-			saslPlainUsername = toNullString(network.SASL.Plain.Username)
-			saslPlainPassword = toNullString(network.SASL.Plain.Password)
-			network.SASL.External.CertBlob = nil
-			network.SASL.External.PrivKeyBlob = nil
-		case "EXTERNAL":
-			// keep saslPlain* nil
-		default:
-			return fmt.Errorf("soju: cannot store network: unsupported SASL mechanism %q", network.SASL.Mechanism)
-		}
-	}
-
-	var err error
-	if network.ID != 0 {
-		_, err = db.db.Exec(`UPDATE Network
-			SET name = ?, addr = ?, nick = ?, username = ?, realname = ?, pass = ?, connect_commands = ?,
-				sasl_mechanism = ?, sasl_plain_username = ?, sasl_plain_password = ?,
-				sasl_external_cert = ?, sasl_external_key = ?
-			WHERE id = ?`,
-			netName, network.Addr, network.Nick, netUsername, realname, pass, connectCommands,
-			saslMechanism, saslPlainUsername, saslPlainPassword,
-			network.SASL.External.CertBlob, network.SASL.External.PrivKeyBlob,
-			network.ID)
-	} else {
-		var res sql.Result
-		res, err = db.db.Exec(`INSERT INTO Network(user, name, addr, nick, username,
-				realname, pass, connect_commands, sasl_mechanism, sasl_plain_username,
-				sasl_plain_password, sasl_external_cert, sasl_external_key)
-			VALUES (?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?)`,
-			userID, netName, network.Addr, network.Nick, netUsername, realname, pass, connectCommands,
-			saslMechanism, saslPlainUsername, saslPlainPassword, network.SASL.External.CertBlob,
-			network.SASL.External.PrivKeyBlob)
-		if err != nil {
-			return err
-		}
-		network.ID, err = res.LastInsertId()
-	}
-	return err
-}
-
-func (db *DB) DeleteNetwork(id int64) error {
-	db.lock.Lock()
-	defer db.lock.Unlock()
-
-	tx, err := db.db.Begin()
-	if err != nil {
-		return err
-	}
-	defer tx.Rollback()
-
-	_, err = tx.Exec("DELETE FROM Channel WHERE network = ?", id)
-	if err != nil {
-		return err
-	}
-
-	_, err = tx.Exec("DELETE FROM Network WHERE id = ?", id)
-	if err != nil {
-		return err
-	}
-
-	return tx.Commit()
-}
-
-func (db *DB) ListChannels(networkID int64) ([]Channel, error) {
-	db.lock.RLock()
-	defer db.lock.RUnlock()
-
-	rows, err := db.db.Query(`SELECT
-			id, name, key, detached, detached_internal_msgid,
-			relay_detached, reattach_on, detach_after, detach_on
-		FROM Channel
-		WHERE network = ?`, networkID)
-	if err != nil {
-		return nil, err
-	}
-	defer rows.Close()
-
-	var channels []Channel
-	for rows.Next() {
-		var ch Channel
-		var key, detachedInternalMsgID sql.NullString
-		var detachAfter int64
-		if err := rows.Scan(&ch.ID, &ch.Name, &key, &ch.Detached, &detachedInternalMsgID, &ch.RelayDetached, &ch.ReattachOn, &detachAfter, &ch.DetachOn); err != nil {
-			return nil, err
-		}
-		ch.Key = key.String
-		ch.DetachedInternalMsgID = detachedInternalMsgID.String
-		ch.DetachAfter = time.Duration(detachAfter) * time.Second
-		channels = append(channels, ch)
-	}
-	if err := rows.Err(); err != nil {
-		return nil, err
-	}
-
-	return channels, nil
-}
-
-func (db *DB) StoreChannel(networkID int64, ch *Channel) error {
-	db.lock.Lock()
-	defer db.lock.Unlock()
-
-	key := toNullString(ch.Key)
-	detachAfter := int64(math.Ceil(ch.DetachAfter.Seconds()))
-
-	var err error
-	if ch.ID != 0 {
-		_, err = db.db.Exec(`UPDATE Channel
-			SET network = ?, name = ?, key = ?, detached = ?, detached_internal_msgid = ?, relay_detached = ?, reattach_on = ?, detach_after = ?, detach_on = ?
-			WHERE id = ?`,
-			networkID, ch.Name, key, ch.Detached, toNullString(ch.DetachedInternalMsgID), ch.RelayDetached, ch.ReattachOn, detachAfter, ch.DetachOn, ch.ID)
-	} else {
-		var res sql.Result
-		res, err = db.db.Exec(`INSERT INTO Channel(network, name, key, detached, detached_internal_msgid, relay_detached, reattach_on, detach_after, detach_on)
-			VALUES (?, ?, ?, ?, ?, ?, ?, ?, ?)`,
-			networkID, ch.Name, key, ch.Detached, toNullString(ch.DetachedInternalMsgID), ch.RelayDetached, ch.ReattachOn, detachAfter, ch.DetachOn)
-		if err != nil {
-			return err
-		}
-		ch.ID, err = res.LastInsertId()
-	}
-	return err
-}
-
-func (db *DB) DeleteChannel(id int64) error {
-	db.lock.Lock()
-	defer db.lock.Unlock()
-
-	_, err := db.db.Exec("DELETE FROM Channel WHERE id = ?", id)
-	return err
-}
-
-func (db *DB) ListDeliveryReceipts(networkID int64) ([]DeliveryReceipt, error) {
-	db.lock.RLock()
-	defer db.lock.RUnlock()
-
-	rows, err := db.db.Query(`SELECT id, target, client, internal_msgid
-		FROM DeliveryReceipt
-		WHERE network = ?`, networkID)
-	if err != nil {
-		return nil, err
-	}
-	defer rows.Close()
-
-	var receipts []DeliveryReceipt
-	for rows.Next() {
-		var rcpt DeliveryReceipt
-		var client sql.NullString
-		if err := rows.Scan(&rcpt.ID, &rcpt.Target, &client, &rcpt.InternalMsgID); err != nil {
-			return nil, err
-		}
-		rcpt.Client = client.String
-		receipts = append(receipts, rcpt)
-	}
-	if err := rows.Err(); err != nil {
-		return nil, err
-	}
-
-	return receipts, nil
-}
-
-func (db *DB) StoreClientDeliveryReceipts(networkID int64, client string, receipts []DeliveryReceipt) error {
-	db.lock.Lock()
-	defer db.lock.Unlock()
-
-	tx, err := db.db.Begin()
-	if err != nil {
-		return err
-	}
-	defer tx.Rollback()
-
-	_, err = tx.Exec("DELETE FROM DeliveryReceipt WHERE network = ? AND client = ?",
-		networkID, toNullString(client))
-	if err != nil {
-		return err
-	}
-
-	for i := range receipts {
-		rcpt := &receipts[i]
-
-		res, err := tx.Exec("INSERT INTO DeliveryReceipt(network, target, client, internal_msgid) VALUES (?, ?, ?, ?)",
-			networkID, rcpt.Target, toNullString(client), rcpt.InternalMsgID)
-		if err != nil {
-			return err
-		}
-		rcpt.ID, err = res.LastInsertId()
-		if err != nil {
-			return err
-		}
-	}
-
-	return tx.Commit()
-}

db_sqlite.go

@@ -0,0 +1,559 @@
+package soju
+
+import (
+	"database/sql"
+	"fmt"
+	"math"
+	"strings"
+	"sync"
+	"time"
+
+	_ "github.com/mattn/go-sqlite3"
+)
+
+const sqliteSchema = `
+CREATE TABLE User (
+	id INTEGER PRIMARY KEY,
+	username VARCHAR(255) NOT NULL UNIQUE,
+	password VARCHAR(255),
+	admin INTEGER NOT NULL DEFAULT 0
+);
+
+CREATE TABLE Network (
+	id INTEGER PRIMARY KEY,
+	name VARCHAR(255),
+	user INTEGER NOT NULL,
+	addr VARCHAR(255) NOT NULL,
+	nick VARCHAR(255) NOT NULL,
+	username VARCHAR(255),
+	realname VARCHAR(255),
+	pass VARCHAR(255),
+	connect_commands VARCHAR(1023),
+	sasl_mechanism VARCHAR(255),
+	sasl_plain_username VARCHAR(255),
+	sasl_plain_password VARCHAR(255),
+	sasl_external_cert BLOB DEFAULT NULL,
+	sasl_external_key BLOB DEFAULT NULL,
+	FOREIGN KEY(user) REFERENCES User(id),
+	UNIQUE(user, addr, nick),
+	UNIQUE(user, name)
+);
+
+CREATE TABLE Channel (
+	id INTEGER PRIMARY KEY,
+	network INTEGER NOT NULL,
+	name VARCHAR(255) NOT NULL,
+	key VARCHAR(255),
+	detached INTEGER NOT NULL DEFAULT 0,
+	detached_internal_msgid VARCHAR(255),
+	relay_detached INTEGER NOT NULL DEFAULT 0,
+	reattach_on INTEGER NOT NULL DEFAULT 0,
+	detach_after INTEGER NOT NULL DEFAULT 0,
+	detach_on INTEGER NOT NULL DEFAULT 0,
+	FOREIGN KEY(network) REFERENCES Network(id),
+	UNIQUE(network, name)
+);
+
+CREATE TABLE DeliveryReceipt (
+	id INTEGER PRIMARY KEY,
+	network INTEGER NOT NULL,
+	target VARCHAR(255) NOT NULL,
+	client VARCHAR(255),
+	internal_msgid VARCHAR(255) NOT NULL,
+	FOREIGN KEY(network) REFERENCES Network(id),
+	UNIQUE(network, target, client)
+);
+`
+
+var sqliteMigrations = []string{
+	"", // migration #0 is reserved for schema initialization
+	"ALTER TABLE Network ADD COLUMN connect_commands VARCHAR(1023)",
+	"ALTER TABLE Channel ADD COLUMN detached INTEGER NOT NULL DEFAULT 0",
+	"ALTER TABLE Network ADD COLUMN sasl_external_cert BLOB DEFAULT NULL",
+	"ALTER TABLE Network ADD COLUMN sasl_external_key BLOB DEFAULT NULL",
+	"ALTER TABLE User ADD COLUMN admin INTEGER NOT NULL DEFAULT 0",
+	`
+		CREATE TABLE UserNew (
+			id INTEGER PRIMARY KEY,
+			username VARCHAR(255) NOT NULL UNIQUE,
+			password VARCHAR(255),
+			admin INTEGER NOT NULL DEFAULT 0
+		);
+		INSERT INTO UserNew SELECT rowid, username, password, admin FROM User;
+		DROP TABLE User;
+		ALTER TABLE UserNew RENAME TO User;
+	`,
+	`
+		CREATE TABLE NetworkNew (
+			id INTEGER PRIMARY KEY,
+			name VARCHAR(255),
+			user INTEGER NOT NULL,
+			addr VARCHAR(255) NOT NULL,
+			nick VARCHAR(255) NOT NULL,
+			username VARCHAR(255),
+			realname VARCHAR(255),
+			pass VARCHAR(255),
+			connect_commands VARCHAR(1023),
+			sasl_mechanism VARCHAR(255),
+			sasl_plain_username VARCHAR(255),
+			sasl_plain_password VARCHAR(255),
+			sasl_external_cert BLOB DEFAULT NULL,
+			sasl_external_key BLOB DEFAULT NULL,
+			FOREIGN KEY(user) REFERENCES User(id),
+			UNIQUE(user, addr, nick),
+			UNIQUE(user, name)
+		);
+		INSERT INTO NetworkNew
+			SELECT Network.id, name, User.id as user, addr, nick,
+				Network.username, realname, pass, connect_commands,
+				sasl_mechanism, sasl_plain_username, sasl_plain_password,
+				sasl_external_cert, sasl_external_key
+			FROM Network
+			JOIN User ON Network.user = User.username;
+		DROP TABLE Network;
+		ALTER TABLE NetworkNew RENAME TO Network;
+	`,
+	`
+		ALTER TABLE Channel ADD COLUMN relay_detached INTEGER NOT NULL DEFAULT 0;
+		ALTER TABLE Channel ADD COLUMN reattach_on INTEGER NOT NULL DEFAULT 0;
+		ALTER TABLE Channel ADD COLUMN detach_after INTEGER NOT NULL DEFAULT 0;
+		ALTER TABLE Channel ADD COLUMN detach_on INTEGER NOT NULL DEFAULT 0;
+	`,
+	`
+		CREATE TABLE DeliveryReceipt (
+			id INTEGER PRIMARY KEY,
+			network INTEGER NOT NULL,
+			target VARCHAR(255) NOT NULL,
+			client VARCHAR(255),
+			internal_msgid VARCHAR(255) NOT NULL,
+			FOREIGN KEY(network) REFERENCES Network(id),
+			UNIQUE(network, target, client)
+		);
+	`,
+	"ALTER TABLE Channel ADD COLUMN detached_internal_msgid VARCHAR(255)",
+}
+
+type SqliteDB struct {
+	lock sync.RWMutex
+	db   *sql.DB
+}
+
+func OpenSqliteDB(driver, source string) (Database, error) {
+	sqlSqliteDB, err := sql.Open(driver, source)
+	if err != nil {
+		return nil, err
+	}
+
+	db := &SqliteDB{db: sqlSqliteDB}
+	if err := db.upgrade(); err != nil {
+		return nil, err
+	}
+
+	return db, nil
+}
+
+func (db *SqliteDB) Close() error {
+	db.lock.Lock()
+	defer db.lock.Unlock()
+	return db.db.Close()
+}
+
+func (db *SqliteDB) upgrade() error {
+	db.lock.Lock()
+	defer db.lock.Unlock()
+
+	var version int
+	if err := db.db.QueryRow("PRAGMA user_version").Scan(&version); err != nil {
+		return fmt.Errorf("failed to query schema version: %v", err)
+	}
+
+	if version == len(sqliteMigrations) {
+		return nil
+	} else if version > len(sqliteMigrations) {
+		return fmt.Errorf("soju (version %d) older than schema (version %d)", len(sqliteMigrations), version)
+	}
+
+	tx, err := db.db.Begin()
+	if err != nil {
+		return err
+	}
+	defer tx.Rollback()
+
+	if version == 0 {
+		if _, err := tx.Exec(sqliteSchema); err != nil {
+			return fmt.Errorf("failed to initialize schema: %v", err)
+		}
+	} else {
+		for i := version; i < len(sqliteMigrations); i++ {
+			if _, err := tx.Exec(sqliteMigrations[i]); err != nil {
+				return fmt.Errorf("failed to execute migration #%v: %v", i, err)
+			}
+		}
+	}
+
+	// For some reason prepared statements don't work here
+	_, err = tx.Exec(fmt.Sprintf("PRAGMA user_version = %d", len(sqliteMigrations)))
+	if err != nil {
+		return fmt.Errorf("failed to bump schema version: %v", err)
+	}
+
+	return tx.Commit()
+}
+
+func toNullString(s string) sql.NullString {
+	return sql.NullString{
+		String: s,
+		Valid:  s != "",
+	}
+}
+
+func (db *SqliteDB) ListUsers() ([]User, error) {
+	db.lock.RLock()
+	defer db.lock.RUnlock()
+
+	rows, err := db.db.Query("SELECT id, username, password, admin FROM User")
+	if err != nil {
+		return nil, err
+	}
+	defer rows.Close()
+
+	var users []User
+	for rows.Next() {
+		var user User
+		var password sql.NullString
+		if err := rows.Scan(&user.ID, &user.Username, &password, &user.Admin); err != nil {
+			return nil, err
+		}
+		user.Password = password.String
+		users = append(users, user)
+	}
+	if err := rows.Err(); err != nil {
+		return nil, err
+	}
+
+	return users, nil
+}
+
+func (db *SqliteDB) GetUser(username string) (*User, error) {
+	db.lock.RLock()
+	defer db.lock.RUnlock()
+
+	user := &User{Username: username}
+
+	var password sql.NullString
+	row := db.db.QueryRow("SELECT id, password, admin FROM User WHERE username = ?", username)
+	if err := row.Scan(&user.ID, &password, &user.Admin); err != nil {
+		return nil, err
+	}
+	user.Password = password.String
+	return user, nil
+}
+
+func (db *SqliteDB) StoreUser(user *User) error {
+	db.lock.Lock()
+	defer db.lock.Unlock()
+
+	password := toNullString(user.Password)
+
+	var err error
+	if user.ID != 0 {
+		_, err = db.db.Exec("UPDATE User SET password = ?, admin = ? WHERE username = ?",
+			password, user.Admin, user.Username)
+	} else {
+		var res sql.Result
+		res, err = db.db.Exec("INSERT INTO User(username, password, admin) VALUES (?, ?, ?)",
+			user.Username, password, user.Admin)
+		if err != nil {
+			return err
+		}
+		user.ID, err = res.LastInsertId()
+	}
+
+	return err
+}
+
+func (db *SqliteDB) DeleteUser(id int64) error {
+	db.lock.Lock()
+	defer db.lock.Unlock()
+
+	tx, err := db.db.Begin()
+	if err != nil {
+		return err
+	}
+	defer tx.Rollback()
+
+	_, err = tx.Exec(`DELETE FROM Channel
+		WHERE id IN (
+			SELECT Channel.id
+			FROM Channel
+			JOIN Network ON Channel.network = Network.id
+			WHERE Network.user = ?
+		)`, id)
+	if err != nil {
+		return err
+	}
+
+	_, err = tx.Exec("DELETE FROM Network WHERE user = ?", id)
+	if err != nil {
+		return err
+	}
+
+	_, err = tx.Exec("DELETE FROM User WHERE id = ?", id)
+	if err != nil {
+		return err
+	}
+
+	return tx.Commit()
+}
+
+func (db *SqliteDB) ListNetworks(userID int64) ([]Network, error) {
+	db.lock.RLock()
+	defer db.lock.RUnlock()
+
+	rows, err := db.db.Query(`SELECT id, name, addr, nick, username, realname, pass,
+			connect_commands, sasl_mechanism, sasl_plain_username, sasl_plain_password,
+			sasl_external_cert, sasl_external_key
+		FROM Network
+		WHERE user = ?`,
+		userID)
+	if err != nil {
+		return nil, err
+	}
+	defer rows.Close()
+
+	var networks []Network
+	for rows.Next() {
+		var net Network
+		var name, username, realname, pass, connectCommands sql.NullString
+		var saslMechanism, saslPlainUsername, saslPlainPassword sql.NullString
+		err := rows.Scan(&net.ID, &name, &net.Addr, &net.Nick, &username, &realname,
+			&pass, &connectCommands, &saslMechanism, &saslPlainUsername, &saslPlainPassword,
+			&net.SASL.External.CertBlob, &net.SASL.External.PrivKeyBlob)
+		if err != nil {
+			return nil, err
+		}
+		net.Name = name.String
+		net.Username = username.String
+		net.Realname = realname.String
+		net.Pass = pass.String
+		if connectCommands.Valid {
+			net.ConnectCommands = strings.Split(connectCommands.String, "\r\n")
+		}
+		net.SASL.Mechanism = saslMechanism.String
+		net.SASL.Plain.Username = saslPlainUsername.String
+		net.SASL.Plain.Password = saslPlainPassword.String
+		networks = append(networks, net)
+	}
+	if err := rows.Err(); err != nil {
+		return nil, err
+	}
+
+	return networks, nil
+}
+
+func (db *SqliteDB) StoreNetwork(userID int64, network *Network) error {
+	db.lock.Lock()
+	defer db.lock.Unlock()
+
+	netName := toNullString(network.Name)
+	netUsername := toNullString(network.Username)
+	realname := toNullString(network.Realname)
+	pass := toNullString(network.Pass)
+	connectCommands := toNullString(strings.Join(network.ConnectCommands, "\r\n"))
+
+	var saslMechanism, saslPlainUsername, saslPlainPassword sql.NullString
+	if network.SASL.Mechanism != "" {
+		saslMechanism = toNullString(network.SASL.Mechanism)
+		switch network.SASL.Mechanism {
+		case "PLAIN":
+			saslPlainUsername = toNullString(network.SASL.Plain.Username)
+			saslPlainPassword = toNullString(network.SASL.Plain.Password)
+			network.SASL.External.CertBlob = nil
+			network.SASL.External.PrivKeyBlob = nil
+		case "EXTERNAL":
+			// keep saslPlain* nil
+		default:
+			return fmt.Errorf("soju: cannot store network: unsupported SASL mechanism %q", network.SASL.Mechanism)
+		}
+	}
+
+	var err error
+	if network.ID != 0 {
+		_, err = db.db.Exec(`UPDATE Network
+			SET name = ?, addr = ?, nick = ?, username = ?, realname = ?, pass = ?, connect_commands = ?,
+				sasl_mechanism = ?, sasl_plain_username = ?, sasl_plain_password = ?,
+				sasl_external_cert = ?, sasl_external_key = ?
+			WHERE id = ?`,
+			netName, network.Addr, network.Nick, netUsername, realname, pass, connectCommands,
+			saslMechanism, saslPlainUsername, saslPlainPassword,
+			network.SASL.External.CertBlob, network.SASL.External.PrivKeyBlob,
+			network.ID)
+	} else {
+		var res sql.Result
+		res, err = db.db.Exec(`INSERT INTO Network(user, name, addr, nick, username,
+				realname, pass, connect_commands, sasl_mechanism, sasl_plain_username,
+				sasl_plain_password, sasl_external_cert, sasl_external_key)
+			VALUES (?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?)`,
+			userID, netName, network.Addr, network.Nick, netUsername, realname, pass, connectCommands,
+			saslMechanism, saslPlainUsername, saslPlainPassword, network.SASL.External.CertBlob,
+			network.SASL.External.PrivKeyBlob)
+		if err != nil {
+			return err
+		}
+		network.ID, err = res.LastInsertId()
+	}
+	return err
+}
+
+func (db *SqliteDB) DeleteNetwork(id int64) error {
+	db.lock.Lock()
+	defer db.lock.Unlock()
+
+	tx, err := db.db.Begin()
+	if err != nil {
+		return err
+	}
+	defer tx.Rollback()
+
+	_, err = tx.Exec("DELETE FROM Channel WHERE network = ?", id)
+	if err != nil {
+		return err
+	}
+
+	_, err = tx.Exec("DELETE FROM Network WHERE id = ?", id)
+	if err != nil {
+		return err
+	}
+
+	return tx.Commit()
+}
+
+func (db *SqliteDB) ListChannels(networkID int64) ([]Channel, error) {
+	db.lock.RLock()
+	defer db.lock.RUnlock()
+
+	rows, err := db.db.Query(`SELECT
+			id, name, key, detached, detached_internal_msgid,
+			relay_detached, reattach_on, detach_after, detach_on
+		FROM Channel
+		WHERE network = ?`, networkID)
+	if err != nil {
+		return nil, err
+	}
+	defer rows.Close()
+
+	var channels []Channel
+	for rows.Next() {
+		var ch Channel
+		var key, detachedInternalMsgID sql.NullString
+		var detachAfter int64
+		if err := rows.Scan(&ch.ID, &ch.Name, &key, &ch.Detached, &detachedInternalMsgID, &ch.RelayDetached, &ch.ReattachOn, &detachAfter, &ch.DetachOn); err != nil {
+			return nil, err
+		}
+		ch.Key = key.String
+		ch.DetachedInternalMsgID = detachedInternalMsgID.String
+		ch.DetachAfter = time.Duration(detachAfter) * time.Second
+		channels = append(channels, ch)
+	}
+	if err := rows.Err(); err != nil {
+		return nil, err
+	}
+
+	return channels, nil
+}
+
+func (db *SqliteDB) StoreChannel(networkID int64, ch *Channel) error {
+	db.lock.Lock()
+	defer db.lock.Unlock()
+
+	key := toNullString(ch.Key)
+	detachAfter := int64(math.Ceil(ch.DetachAfter.Seconds()))
+
+	var err error
+	if ch.ID != 0 {
+		_, err = db.db.Exec(`UPDATE Channel
+			SET network = ?, name = ?, key = ?, detached = ?, detached_internal_msgid = ?, relay_detached = ?, reattach_on = ?, detach_after = ?, detach_on = ?
+			WHERE id = ?`,
+			networkID, ch.Name, key, ch.Detached, toNullString(ch.DetachedInternalMsgID), ch.RelayDetached, ch.ReattachOn, detachAfter, ch.DetachOn, ch.ID)
+	} else {
+		var res sql.Result
+		res, err = db.db.Exec(`INSERT INTO Channel(network, name, key, detached, detached_internal_msgid, relay_detached, reattach_on, detach_after, detach_on)
+			VALUES (?, ?, ?, ?, ?, ?, ?, ?, ?)`,
+			networkID, ch.Name, key, ch.Detached, toNullString(ch.DetachedInternalMsgID), ch.RelayDetached, ch.ReattachOn, detachAfter, ch.DetachOn)
+		if err != nil {
+			return err
+		}
+		ch.ID, err = res.LastInsertId()
+	}
+	return err
+}
+
+func (db *SqliteDB) DeleteChannel(id int64) error {
+	db.lock.Lock()
+	defer db.lock.Unlock()
+
+	_, err := db.db.Exec("DELETE FROM Channel WHERE id = ?", id)
+	return err
+}
+
+func (db *SqliteDB) ListDeliveryReceipts(networkID int64) ([]DeliveryReceipt, error) {
+	db.lock.RLock()
+	defer db.lock.RUnlock()
+
+	rows, err := db.db.Query(`SELECT id, target, client, internal_msgid
+		FROM DeliveryReceipt
+		WHERE network = ?`, networkID)
+	if err != nil {
+		return nil, err
+	}
+	defer rows.Close()
+
+	var receipts []DeliveryReceipt
+	for rows.Next() {
+		var rcpt DeliveryReceipt
+		var client sql.NullString
+		if err := rows.Scan(&rcpt.ID, &rcpt.Target, &client, &rcpt.InternalMsgID); err != nil {
+			return nil, err
+		}
+		rcpt.Client = client.String
+		receipts = append(receipts, rcpt)
+	}
+	if err := rows.Err(); err != nil {
+		return nil, err
+	}
+
+	return receipts, nil
+}
+
+func (db *SqliteDB) StoreClientDeliveryReceipts(networkID int64, client string, receipts []DeliveryReceipt) error {
+	db.lock.Lock()
+	defer db.lock.Unlock()
+
+	tx, err := db.db.Begin()
+	if err != nil {
+		return err
+	}
+	defer tx.Rollback()
+
+	_, err = tx.Exec("DELETE FROM DeliveryReceipt WHERE network = ? AND client = ?",
+		networkID, toNullString(client))
+	if err != nil {
+		return err
+	}
+
+	for i := range receipts {
+		rcpt := &receipts[i]
+
+		res, err := tx.Exec("INSERT INTO DeliveryReceipt(network, target, client, internal_msgid) VALUES (?, ?, ?, ?)",
+			networkID, rcpt.Target, toNullString(client), rcpt.InternalMsgID)
+		if err != nil {
+			return err
+		}
+		rcpt.ID, err = res.LastInsertId()
+		if err != nil {
+			return err
+		}
+	}
+
+	return tx.Commit()
+}

server.go

@@ -56,7 +56,7 @@ type Server struct {
 	AcceptProxyIPs config.IPSet
 	Identd         *Identd // can be nil
 
-	db     *DB
+	db     Database
 	stopWG sync.WaitGroup
 
 	lock      sync.Mutex
@@ -64,7 +64,7 @@ type Server struct {
 	users     map[string]*user
 }
 
-func NewServer(db *DB) *Server {
+func NewServer(db Database) *Server {
 	return &Server{
 		Logger:       log.New(log.Writer(), "", log.LstdFlags),
 		HistoryLimit: 1000,