source: code/trunk/db.go@ 262

package soju

import (
        "database/sql"
        "fmt"
        "sync"

        _ "github.com/mattn/go-sqlite3"
)

type User struct {
        Username string
        Password string // hashed
}

type SASL struct {
        Mechanism string

        Plain struct {
                Username string
                Password string
        }
}

type Network struct {
        ID       int64
        Name     string
        Addr     string
        Nick     string
        Username string
        Realname string
        Pass     string
        SASL     SASL
}

func (net *Network) GetName() string {
        if net.Name != "" {
                return net.Name
        }
        return net.Addr
}

type Channel struct {
        ID   int64
        Name string
        Key  string
}

var ErrNoSuchChannel = fmt.Errorf("soju: no such channel")

const schema = `
CREATE TABLE User (
        username VARCHAR(255) PRIMARY KEY,
        password VARCHAR(255) NOT NULL
);

CREATE TABLE Network (
        id INTEGER PRIMARY KEY,
        name VARCHAR(255),
        user VARCHAR(255) NOT NULL,
        addr VARCHAR(255) NOT NULL,
        nick VARCHAR(255) NOT NULL,
        username VARCHAR(255),
        realname VARCHAR(255),
        pass VARCHAR(255),
        sasl_mechanism VARCHAR(255),
        sasl_plain_username VARCHAR(255),
        sasl_plain_password VARCHAR(255),
        FOREIGN KEY(user) REFERENCES User(username),
        UNIQUE(user, addr, nick)
);

CREATE TABLE Channel (
        id INTEGER PRIMARY KEY,
        network INTEGER NOT NULL,
        name VARCHAR(255) NOT NULL,
        key VARCHAR(255),
        FOREIGN KEY(network) REFERENCES Network(id),
        UNIQUE(network, name)
);
`

var migrations = []string{
        "", // migration #0 is reserved for schema initialization
}

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.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 fromStringPtr(ptr *string) string {
        if ptr == nil {
                return ""
        }
        return *ptr
}

func toStringPtr(s string) *string {
        if s == "" {
                return nil
        }
        return &s
}

func (db *DB) ListUsers() ([]User, error) {
        db.lock.RLock()
        defer db.lock.RUnlock()

        rows, err := db.db.Query("SELECT username, password FROM User")
        if err != nil {
                return nil, err
        }
        defer rows.Close()

        var users []User
        for rows.Next() {
                var user User
                var password *string
                if err := rows.Scan(&user.Username, &password); err != nil {
                        return nil, err
                }
                user.Password = fromStringPtr(password)
                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 *string
        row := db.db.QueryRow("SELECT password FROM User WHERE username = ?", username)
        if err := row.Scan(&password); err != nil {
                return nil, err
        }
        user.Password = fromStringPtr(password)
        return user, nil
}

func (db *DB) CreateUser(user *User) error {
        db.lock.Lock()
        defer db.lock.Unlock()

        password := toStringPtr(user.Password)
        _, err := db.db.Exec("INSERT INTO User(username, password) VALUES (?, ?)", user.Username, password)
        return err
}

func (db *DB) UpdatePassword(user *User) error {
        db.lock.Lock()
        defer db.lock.Unlock()

        password := toStringPtr(user.Password)
        _, err := db.db.Exec(`UPDATE User
        SET password = ?
        WHERE username = ?`,
                password, user.Username)
        return err
}

func (db *DB) ListNetworks(username string) ([]Network, error) {
        db.lock.RLock()
        defer db.lock.RUnlock()

        rows, err := db.db.Query(`SELECT id, name, addr, nick, username, realname, pass,
                        sasl_mechanism, sasl_plain_username, sasl_plain_password
                FROM Network
                WHERE user = ?`,
                username)
        if err != nil {
                return nil, err
        }
        defer rows.Close()

        var networks []Network
        for rows.Next() {
                var net Network
                var name, username, realname, pass *string
                var saslMechanism, saslPlainUsername, saslPlainPassword *string
                err := rows.Scan(&net.ID, &name, &net.Addr, &net.Nick, &username, &realname,
                        &pass, &saslMechanism, &saslPlainUsername, &saslPlainPassword)
                if err != nil {
                        return nil, err
                }
                net.Name = fromStringPtr(name)
                net.Username = fromStringPtr(username)
                net.Realname = fromStringPtr(realname)
                net.Pass = fromStringPtr(pass)
                net.SASL.Mechanism = fromStringPtr(saslMechanism)
                net.SASL.Plain.Username = fromStringPtr(saslPlainUsername)
                net.SASL.Plain.Password = fromStringPtr(saslPlainPassword)
                networks = append(networks, net)
        }
        if err := rows.Err(); err != nil {
                return nil, err
        }

        return networks, nil
}

func (db *DB) StoreNetwork(username string, network *Network) error {
        db.lock.Lock()
        defer db.lock.Unlock()

        netName := toStringPtr(network.Name)
        netUsername := toStringPtr(network.Username)
        realname := toStringPtr(network.Realname)
        pass := toStringPtr(network.Pass)

        var saslMechanism, saslPlainUsername, saslPlainPassword *string
        if network.SASL.Mechanism != "" {
                saslMechanism = &network.SASL.Mechanism
                switch network.SASL.Mechanism {
                case "PLAIN":
                        saslPlainUsername = toStringPtr(network.SASL.Plain.Username)
                        saslPlainPassword = toStringPtr(network.SASL.Plain.Password)
                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 = ?,
                                sasl_mechanism = ?, sasl_plain_username = ?, sasl_plain_password = ?
                        WHERE id = ?`,
                        netName, network.Addr, network.Nick, netUsername, realname, pass,
                        saslMechanism, saslPlainUsername, saslPlainPassword, network.ID)
        } else {
                var res sql.Result
                res, err = db.db.Exec(`INSERT INTO Network(user, name, addr, nick, username,
                                realname, pass, sasl_mechanism, sasl_plain_username,
                                sasl_plain_password)
                        VALUES (?, ?, ?, ?, ?, ?, ?, ?, ?, ?)`,
                        username, netName, network.Addr, network.Nick, netUsername, realname, pass,
                        saslMechanism, saslPlainUsername, saslPlainPassword)
                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 Network WHERE id = ?", id)
        if err != nil {
                return err
        }

        _, err = tx.Exec("DELETE FROM Channel WHERE network = ?", 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 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 *string
                if err := rows.Scan(&ch.ID, &ch.Name, &key); err != nil {
                        return nil, err
                }
                ch.Key = fromStringPtr(key)
                channels = append(channels, ch)
        }
        if err := rows.Err(); err != nil {
                return nil, err
        }

        return channels, nil
}

func (db *DB) GetChannel(networkID int64, name string) (*Channel, error) {
        db.lock.RLock()
        defer db.lock.RUnlock()

        ch := &Channel{Name: name}

        var key *string
        row := db.db.QueryRow("SELECT id, key FROM Channel WHERE network = ? AND name = ?", networkID, name)
        if err := row.Scan(&ch.ID, &key); err == sql.ErrNoRows {
                return nil, ErrNoSuchChannel
        } else if err != nil {
                return nil, err
        }
        ch.Key = fromStringPtr(key)
        return ch, nil
}

func (db *DB) StoreChannel(networkID int64, ch *Channel) error {
        db.lock.Lock()
        defer db.lock.Unlock()

        key := toStringPtr(ch.Key)

        var err error
        if ch.ID != 0 {
                _, err = db.db.Exec(`UPDATE Channel
                        SET network = ?, name = ?, key = ?
                        WHERE id = ?`, networkID, ch.Name, key, ch.ID)
        } else {
                var res sql.Result
                res, err = db.db.Exec(`INSERT INTO Channel(network, name, key)
                        VALUES (?, ?, ?)`, networkID, ch.Name, key)
                if err != nil {
                        return err
                }
                ch.ID, err = res.LastInsertId()
        }
        return err
}

func (db *DB) DeleteChannel(networkID int64, name string) error {
        db.lock.Lock()
        defer db.lock.Unlock()

        _, err := db.db.Exec("DELETE FROM Channel WHERE network = ? AND name = ?", networkID, name)
        return err
}