storage reorganized around a pool and transactions

This commit is contained in:
Jimmy Zelinskie 2013-07-25 10:03:04 -04:00
parent d62a71847d
commit 40505091f5
6 changed files with 240 additions and 200 deletions

View file

@ -23,16 +23,22 @@ func (s Server) serveAnnounce(w http.ResponseWriter, r *http.Request) {
return
}
// Start a transaction
tx, err := s.dbConnPool.Get()
if err != nil {
log.Panicf("server: %s", err)
}
// Validate the user's passkey
passkey, _ := path.Split(r.URL.Path)
user, err := s.FindUser(passkey)
user, err := validateUser(tx, passkey)
if err != nil {
fail(err, w, r)
return
}
// Check if the user's client is whitelisted
whitelisted, err := s.dataStore.ClientWhitelisted(peerID)
whitelisted, err := tx.ClientWhitelisted(peerID)
if err != nil {
log.Panicf("server: %s", err)
}
@ -42,7 +48,7 @@ func (s Server) serveAnnounce(w http.ResponseWriter, r *http.Request) {
}
// Find the specified torrent
torrent, exists, err := s.dataStore.FindTorrent(infohash)
torrent, exists, err := tx.FindTorrent(infohash)
if err != nil {
log.Panicf("server: %s", err)
}
@ -51,15 +57,9 @@ func (s Server) serveAnnounce(w http.ResponseWriter, r *http.Request) {
return
}
// Begin a data store transaction
tx, err := s.dataStore.Begin()
if err != nil {
log.Panicf("server: %s", err)
}
// If the torrent was pruned and the user is seeding, unprune it
if !torrent.Active && left == 0 {
err := tx.Active(torrent)
err := tx.MarkActive(torrent)
if err != nil {
log.Panicf("server: %s", err)
}

View file

@ -15,24 +15,32 @@ import (
)
func (s *Server) serveScrape(w http.ResponseWriter, r *http.Request) {
passkey, _ := path.Split(r.URL.Path)
_, err := s.FindUser(passkey)
if err != nil {
fail(err, w, r)
return
}
// Parse the query
pq, err := parseQuery(r.URL.RawQuery)
if err != nil {
fail(errors.New("Error parsing query"), w, r)
return
}
// Start a transaction
tx, err := s.dbConnPool.Get()
if err != nil {
log.Fatal(err)
}
// Find and validate the user
passkey, _ := path.Split(r.URL.Path)
_, err = validateUser(tx, passkey)
if err != nil {
fail(err, w, r)
return
}
io.WriteString(w, "d")
writeBencoded(w, "files")
if pq.Infohashes != nil {
for _, infohash := range pq.Infohashes {
torrent, exists, err := s.dataStore.FindTorrent(infohash)
torrent, exists, err := tx.FindTorrent(infohash)
if err != nil {
log.Panicf("server: %s", err)
}
@ -42,7 +50,7 @@ func (s *Server) serveScrape(w http.ResponseWriter, r *http.Request) {
}
}
} else if infohash, exists := pq.Params["info_hash"]; exists {
torrent, exists, err := s.dataStore.FindTorrent(infohash)
torrent, exists, err := tx.FindTorrent(infohash)
if err != nil {
log.Panicf("server: %s", err)
}
@ -53,6 +61,7 @@ func (s *Server) serveScrape(w http.ResponseWriter, r *http.Request) {
}
io.WriteString(w, "e")
// Finish up and write headers
r.Close = true
w.Header().Add("Content-Type", "text/plain")
w.Header().Add("Connection", "close")

View file

@ -24,7 +24,7 @@ import (
type Server struct {
conf *config.Config
listener net.Listener
dataStore storage.DS
dbConnPool storage.Pool
serving bool
startTime time.Time
@ -38,14 +38,14 @@ type Server struct {
}
func New(conf *config.Config) (*Server, error) {
ds, err := storage.Open(&conf.Storage)
pool, err := storage.Open(&conf.Storage)
if err != nil {
return nil, err
}
s := &Server{
conf: conf,
dataStore: ds,
dbConnPool: pool,
Server: http.Server{
Addr: conf.Addr,
ReadTimeout: conf.ReadTimeout.Duration,
@ -75,7 +75,7 @@ func (s *Server) ListenAndServe() error {
func (s *Server) Stop() error {
s.serving = false
s.waitgroup.Wait()
err := s.dataStore.Close()
err := s.dbConnPool.Close()
if err != nil {
return err
}
@ -121,13 +121,13 @@ func fail(err error, w http.ResponseWriter, r *http.Request) {
w.(http.Flusher).Flush()
}
func (s *Server) FindUser(dir string) (*storage.User, error) {
func validateUser(tx storage.Tx, dir string) (*storage.User, error) {
if len(dir) != 34 {
return nil, errors.New("Passkey is invalid")
}
passkey := dir[1:33]
user, exists, err := s.dataStore.FindUser(passkey)
user, exists, err := tx.FindUser(passkey)
if err != nil {
log.Panicf("server: %s", err)
}

View file

@ -12,6 +12,7 @@ package redis
import (
"encoding/json"
"errors"
"strings"
"time"
@ -23,10 +24,10 @@ import (
type driver struct{}
func (d *driver) New(conf *config.Storage) storage.DS {
return &DS{
func (d *driver) New(conf *config.Storage) storage.Pool {
return &Pool{
conf: conf,
Pool: redis.Pool{
pool: redis.Pool{
MaxIdle: conf.MaxIdleConn,
IdleTimeout: conf.IdleTimeout.Duration,
Dial: makeDialFunc(conf),
@ -65,17 +66,90 @@ func testOnBorrow(c redis.Conn, t time.Time) error {
return err
}
type DS struct {
type Pool struct {
conf *config.Storage
redis.Pool
pool redis.Pool
}
func (ds *DS) FindUser(passkey string) (*storage.User, bool, error) {
conn := ds.Get()
defer conn.Close()
func (p *Pool) Close() error {
return p.pool.Close()
}
key := ds.conf.Prefix + "user:" + passkey
reply, err := redis.String(conn.Do("GET", key))
func (p *Pool) Get() (storage.Tx, error) {
return &Tx{
conf: p.conf,
done: false,
multi: false,
Conn: p.pool.Get(),
}, nil
}
// Tx represents a transaction for Redis with one gotcha:
// all reads must be done prior to any writes. Writes will
// check if the MULTI command has been sent to redis and will
// send it if it hasn't.
//
// Internally a transaction looks like:
// WATCH keyA
// GET keyA
// WATCH keyB
// GET keyB
// MULTI
// SET keyA
// SET keyB
// EXEC
type Tx struct {
conf *config.Storage
done bool
multi bool
redis.Conn
}
func (tx *Tx) close() {
if tx.done {
panic("redis: transaction closed twice")
}
tx.done = true
tx.Conn.Close()
}
func (tx *Tx) Commit() error {
if tx.done {
return storage.ErrTxDone
}
if tx.multi == true {
_, err := tx.Do("EXEC")
if err != nil {
return err
}
}
tx.close()
return nil
}
func (tx *Tx) Rollback() error {
if tx.done {
return storage.ErrTxDone
}
// Redis doesn't need to do anything. Exec is atomic.
tx.close()
return nil
}
func (tx *Tx) FindUser(passkey string) (*storage.User, bool, error) {
if tx.done {
return nil, false, storage.ErrTxDone
}
if tx.multi == true {
return nil, false, errors.New("Tried to read during MULTI")
}
key := tx.conf.Prefix + "user:" + passkey
_, err := tx.Do("WATCH", key)
if err != nil {
return nil, false, err
}
reply, err := redis.String(tx.Do("GET", key))
if err != nil {
if err == redis.ErrNil {
return nil, false, nil
@ -91,12 +165,20 @@ func (ds *DS) FindUser(passkey string) (*storage.User, bool, error) {
return user, true, nil
}
func (ds *DS) FindTorrent(infohash string) (*storage.Torrent, bool, error) {
conn := ds.Get()
defer conn.Close()
func (tx *Tx) FindTorrent(infohash string) (*storage.Torrent, bool, error) {
if tx.done {
return nil, false, storage.ErrTxDone
}
if tx.multi == true {
return nil, false, errors.New("Tried to read during MULTI")
}
key := ds.conf.Prefix + "torrent:" + infohash
reply, err := redis.String(conn.Do("GET", key))
key := tx.conf.Prefix + "torrent:" + infohash
_, err := tx.Do("WATCH", key)
if err != nil {
return nil, false, err
}
reply, err := redis.String(tx.Do("GET", key))
if err != nil {
if err == redis.ErrNil {
return nil, false, nil
@ -112,87 +194,65 @@ func (ds *DS) FindTorrent(infohash string) (*storage.Torrent, bool, error) {
return torrent, true, nil
}
func (ds *DS) ClientWhitelisted(peerID string) (bool, error) {
conn := ds.Get()
defer conn.Close()
key := ds.conf.Prefix + "whitelist"
exists, err := redis.Bool(conn.Do("SISMEMBER", key, peerID))
if err != nil {
return false, err
}
return exists, nil
}
type Tx struct {
conf *config.Storage
done bool
redis.Conn
}
func (ds *DS) Begin() (storage.Tx, error) {
conn := ds.Get()
err := conn.Send("MULTI")
if err != nil {
return nil, err
}
return &Tx{
conf: ds.conf,
Conn: conn,
}, nil
}
func (tx *Tx) close() {
func (tx *Tx) ClientWhitelisted(peerID string) (exists bool, err error) {
if tx.done {
panic("redis: transaction closed twice")
return false, storage.ErrTxDone
}
tx.done = true
tx.Conn.Close()
if tx.multi == true {
return false, errors.New("Tried to read during MULTI")
}
func (tx *Tx) Commit() error {
if tx.done {
return storage.ErrTxDone
}
_, err := tx.Do("EXEC")
key := tx.conf.Prefix + "whitelist"
_, err = tx.Do("WATCH", key)
if err != nil {
return err
return
}
tx.close()
return nil
}
// Redis doesn't need to rollback. Exec is atomic.
func (tx *Tx) Rollback() error {
if tx.done {
return storage.ErrTxDone
}
tx.close()
return nil
// TODO
return
}
func (tx *Tx) Snatch(user *storage.User, torrent *storage.Torrent) error {
if tx.done {
return storage.ErrTxDone
}
if tx.multi != true {
err := tx.Send("MULTI")
if err != nil {
return err
}
}
// TODO
return nil
}
func (tx *Tx) Active(t *storage.Torrent) error {
func (tx *Tx) MarkActive(t *storage.Torrent) error {
if tx.done {
return storage.ErrTxDone
}
key := tx.conf.Prefix + "torrent:" + t.Infohash
err := activeScript.Send(tx.Conn, key)
if tx.multi != true {
err := tx.Send("MULTI")
if err != nil {
return err
}
}
// TODO
return nil
}
func (tx *Tx) NewLeecher(t *storage.Torrent, p *storage.Peer) error {
if tx.done {
return storage.ErrTxDone
}
if tx.multi != true {
err := tx.Send("MULTI")
if err != nil {
return err
}
}
// TODO
return nil
}
@ -201,6 +261,13 @@ func (tx *Tx) SetLeecher(t *storage.Torrent, p *storage.Peer) error {
if tx.done {
return storage.ErrTxDone
}
if tx.multi != true {
err := tx.Send("MULTI")
if err != nil {
return err
}
}
// TODO
return nil
}
@ -209,6 +276,13 @@ func (tx *Tx) RmLeecher(t *storage.Torrent, p *storage.Peer) error {
if tx.done {
return storage.ErrTxDone
}
if tx.multi != true {
err := tx.Send("MULTI")
if err != nil {
return err
}
}
// TODO
return nil
}
@ -217,6 +291,13 @@ func (tx *Tx) NewSeeder(t *storage.Torrent, p *storage.Peer) error {
if tx.done {
return storage.ErrTxDone
}
if tx.multi != true {
err := tx.Send("MULTI")
if err != nil {
return err
}
}
// TODO
return nil
}
@ -225,6 +306,13 @@ func (tx *Tx) SetSeeder(t *storage.Torrent, p *storage.Peer) error {
if tx.done {
return storage.ErrTxDone
}
if tx.multi != true {
err := tx.Send("MULTI")
if err != nil {
return err
}
}
// TODO
return nil
}
@ -233,28 +321,46 @@ func (tx *Tx) RmSeeder(t *storage.Torrent, p *storage.Peer) error {
if tx.done {
return storage.ErrTxDone
}
key := tx.conf.Prefix + "torrent:" + t.Infohash
err := rmSeederScript.Send(tx.Conn, key, p.ID)
if tx.multi != true {
err := tx.Send("MULTI")
if err != nil {
return err
}
}
// TODO
return nil
}
func (tx *Tx) IncrementSlots(u *storage.User) error {
if tx.done {
return storage.ErrTxDone
}
key := tx.conf.Prefix + "user:" + u.Passkey
err := incSlotsScript.Send(tx.Conn, key)
if tx.multi != true {
err := tx.Send("MULTI")
if err != nil {
return err
}
}
// TODO
return nil
}
func (tx *Tx) DecrementSlots(u *storage.User) error {
if tx.done {
return storage.ErrTxDone
}
key := tx.conf.Prefix + "user:" + u.Passkey
err := decSlotsScript.Send(tx.Conn, key)
if tx.multi != true {
err := tx.Send("MULTI")
if err != nil {
return err
}
}
// TODO
return nil
}
func init() {
storage.Register("redis", &driver{})

View file

@ -1,67 +0,0 @@
package redis
import (
"github.com/garyburd/redigo/redis"
)
var incSlotsScript = redis.NewScript(1, incSlotsScriptSrc)
const incSlotsScriptSrc = `
if redis.call("exists", keys[1]) == 1 then
local json = redis.call("get", keys[1])
local user = cjson.decode(json)
user["slots_used"] = user["slots_used"] + 1
json = cjson.encode(user)
redis.call("set", key, json)
return user["slots_used"]
else
return nil
end
`
var decSlotsScript = redis.NewScript(1, incSlotsScriptSrc)
const decSlotsScriptSrc = `
if redis.call("exists", keys[1]) == 1 then
local json = redis.call("get", keys[1])
local user = cjson.decode(json)
if user["slots_used"] > 0
user["slots_used"] = user["slots_used"] - 1
end
json = cjson.encode(user)
redis.call("set", key, json)
return user["slots_used"]
else
return nil
end
`
var activeScript = redis.NewScript(1, decSlotsScriptSrc)
const activeScriptSrc = `
if redis.call("exists", keys[1]) == 1 then
local json = redis.call("get", keys[1])
local torrent = cjson.decode(json)
torrent["active"] = true
json = cjson.encode(torrent)
redis.call("set", key, json)
return user["slots_used"]
else
return nil
end
`
var rmSeederScript = redis.NewScript(2, rmSeederScriptSrc)
const rmSeederScriptSrc = `
if redis.call("EXISTS", keys[1]) == 1 then
local json = redis.call("GET", keys[1])
local torrent = cjson.decode(json)
table.remove(torrent["seeders"], keys[2])
json = cjson.encode(torrent)
redis.call("SET", key, json)
return 0
else
return nil
end
`

View file

@ -19,7 +19,7 @@ var (
)
type Driver interface {
New(*config.Storage) DS
New(*config.Storage) Pool
}
// Register makes a database driver available by the provided name.
@ -35,8 +35,8 @@ func Register(name string, driver Driver) {
drivers[name] = driver
}
// Open opens a data store specified by a storage configuration.
func Open(conf *config.Storage) (DS, error) {
// Open creates a pool of data store connections specified by a storage configuration.
func Open(conf *config.Storage) (Pool, error) {
driver, ok := drivers[conf.Driver]
if !ok {
return nil, fmt.Errorf(
@ -48,19 +48,11 @@ func Open(conf *config.Storage) (DS, error) {
return pool, nil
}
// DS represents a data store handle. It's expected to be safe for concurrent
// use by multiple goroutines.
//
// A pool of connections or a database/sql.DB is a great concrete type to
// implement the DS interface.
type DS interface {
// Pool represents a thread-safe pool of connections to the data store
// that can be used to obtain transactions.
type Pool interface {
Close() error
Begin() (Tx, error)
FindUser(passkey string) (*User, bool, error)
FindTorrent(infohash string) (*Torrent, bool, error)
ClientWhitelisted(peerID string) (bool, error)
Get() (Tx, error)
}
// Tx represents an in-progress data store transaction.
@ -72,20 +64,20 @@ type Tx interface {
Commit() error
Rollback() error
// Torrents
// Reads
FindUser(passkey string) (*User, bool, error)
FindTorrent(infohash string) (*Torrent, bool, error)
ClientWhitelisted(peerID string) (bool, error)
// Writes
Snatch(u *User, t *Torrent) error
Active(t *Torrent) error
// Peers
MarkActive(t *Torrent) error
NewLeecher(t *Torrent, p *Peer) error
SetLeecher(t *Torrent, p *Peer) error
RmLeecher(t *Torrent, p *Peer) error
NewSeeder(t *Torrent, p *Peer) error
SetSeeder(t *Torrent, p *Peer) error
RmLeecher(t *Torrent, p *Peer) error
RmSeeder(t *Torrent, p *Peer) error
// Users
SetLeecher(t *Torrent, p *Peer) error
SetSeeder(t *Torrent, p *Peer) error
IncrementSlots(u *User) error
DecrementSlots(u *User) error
}