diff --git a/configuration/configuration.go b/configuration/configuration.go index 7076df85d4..3e74330321 100644 --- a/configuration/configuration.go +++ b/configuration/configuration.go @@ -168,6 +168,9 @@ type Configuration struct { // Addr specifies the the redis instance available to the application. Addr string `yaml:"addr,omitempty"` + // SentinelMasterSet specifies the the redis sentinel master set name. + SentinelMasterSet string `yaml:"sentinelMasterSet,omitempty"` + // Password string to use when making a connection. Password string `yaml:"password,omitempty"` diff --git a/registry/handlers/app.go b/registry/handlers/app.go index bf56cea22a..4a7cee9a2e 100644 --- a/registry/handlers/app.go +++ b/registry/handlers/app.go @@ -3,6 +3,7 @@ package handlers import ( "context" "crypto/rand" + "errors" "expvar" "fmt" "math" @@ -16,6 +17,7 @@ import ( "strings" "time" + "github.com/FZambia/sentinel" "github.com/distribution/reference" "github.com/docker/distribution" "github.com/docker/distribution/configuration" @@ -499,6 +501,45 @@ func (app *App) configureRedis(configuration *configuration.Configuration) { return } + var getRedisAddr func() (string, error) + var testOnBorrow func(c redis.Conn, t time.Time) error + if configuration.Redis.SentinelMasterSet != "" { + sntnl := &sentinel.Sentinel{ + Addrs: strings.Split(configuration.Redis.Addr, ","), + MasterName: configuration.Redis.SentinelMasterSet, + Dial: func(addr string) (redis.Conn, error) { + c, err := redis.DialTimeout("tcp", addr, + configuration.Redis.DialTimeout, + configuration.Redis.ReadTimeout, + configuration.Redis.WriteTimeout) + if err != nil { + return nil, err + } + return c, nil + }, + } + getRedisAddr = func() (string, error) { + return sntnl.MasterAddr() + } + testOnBorrow = func(c redis.Conn, t time.Time) error { + if !sentinel.TestRole(c, "master") { + return errors.New("role check failed") + } + return nil + } + + } else { + getRedisAddr = func() (string, error) { + return configuration.Redis.Addr, nil + } + testOnBorrow = func(c redis.Conn, t time.Time) error { + // TODO(stevvooe): We can probably do something more interesting + // here with the health package. + _, err := c.Do("PING") + return err + } + } + pool := &redis.Pool{ Dial: func() (redis.Conn, error) { // TODO(stevvooe): Yet another use case for contextual timing. @@ -514,8 +555,11 @@ func (app *App) configureRedis(configuration *configuration.Configuration) { } } - conn, err := redis.DialTimeout("tcp", - configuration.Redis.Addr, + redisAddr, err := getRedisAddr() + if err != nil { + return nil, err + } + conn, err := redis.DialTimeout("tcp", redisAddr, configuration.Redis.DialTimeout, configuration.Redis.ReadTimeout, configuration.Redis.WriteTimeout) @@ -547,16 +591,11 @@ func (app *App) configureRedis(configuration *configuration.Configuration) { done(nil) return conn, nil }, - MaxIdle: configuration.Redis.Pool.MaxIdle, - MaxActive: configuration.Redis.Pool.MaxActive, - IdleTimeout: configuration.Redis.Pool.IdleTimeout, - TestOnBorrow: func(c redis.Conn, t time.Time) error { - // TODO(stevvooe): We can probably do something more interesting - // here with the health package. - _, err := c.Do("PING") - return err - }, - Wait: false, // if a connection is not available, proceed without cache. + MaxIdle: configuration.Redis.Pool.MaxIdle, + MaxActive: configuration.Redis.Pool.MaxActive, + IdleTimeout: configuration.Redis.Pool.IdleTimeout, + TestOnBorrow: testOnBorrow, + Wait: false, // if a connection is not available, proceed without cache. } app.redis = pool diff --git a/registry/handlers/app_test.go b/registry/handlers/app_test.go index 60a57e6c15..8a644d83d8 100644 --- a/registry/handlers/app_test.go +++ b/registry/handlers/app_test.go @@ -140,7 +140,29 @@ func TestAppDispatcher(t *testing.T) { // TestNewApp covers the creation of an application via NewApp with a // configuration. func TestNewApp(t *testing.T) { - ctx := context.Background() + + config := configuration.Configuration{ + Storage: configuration.Storage{ + "testdriver": nil, + "maintenance": configuration.Parameters{"uploadpurging": map[interface{}]interface{}{ + "enabled": false, + }}, + }, + Auth: configuration.Auth{ + // For now, we simply test that new auth results in a viable + // application. + "silly": { + "realm": "realm-test", + "service": "service-test", + }, + }, + } + runAppWithConfig(t, config) +} + +// TestNewApp covers the creation of an application via NewApp with a +// configuration(with redis). +func TestNewAppWithRedis(t *testing.T) { config := configuration.Configuration{ Storage: configuration.Storage{ "testdriver": nil, @@ -157,7 +179,38 @@ func TestNewApp(t *testing.T) { }, }, } + config.Redis.Addr = "127.0.0.1:6379" + config.Redis.DB = 0 + runAppWithConfig(t, config) +} +// TestNewApp covers the creation of an application via NewApp with a +// configuration(with redis sentinel cluster). +func TestNewAppWithRedisSentinelCluster(t *testing.T) { + config := configuration.Configuration{ + Storage: configuration.Storage{ + "testdriver": nil, + "maintenance": configuration.Parameters{"uploadpurging": map[interface{}]interface{}{ + "enabled": false, + }}, + }, + Auth: configuration.Auth{ + // For now, we simply test that new auth results in a viable + // application. + "silly": { + "realm": "realm-test", + "service": "service-test", + }, + }, + } + config.Redis.Addr = "192.168.0.11:26379,192.168.0.12:26379" + config.Redis.DB = 0 + config.Redis.SentinelMasterSet = "mymaster" + runAppWithConfig(t, config) +} + +func runAppWithConfig(t *testing.T, config configuration.Configuration) { + ctx := context.Background() // Mostly, with this test, given a sane configuration, we are simply // ensuring that NewApp doesn't panic. We might want to tweak this // behavior. diff --git a/vendor.conf b/vendor.conf index 33fe616b76..a8d8f58bc6 100644 --- a/vendor.conf +++ b/vendor.conf @@ -51,3 +51,4 @@ gopkg.in/yaml.v2 v2.2.1 rsc.io/letsencrypt e770c10b0f1a64775ae91d240407ce00d1a5bdeb https://github.com/dmcgowan/letsencrypt.git github.com/opencontainers/go-digest ea51bea511f75cfa3ef6098cc253c5c3609b037a # v1.0.0 github.com/opencontainers/image-spec 67d2d5658fe0476ab9bf414cec164077ebff3920 # v1.0.2 +github.com/FZambia/sentinel 5585739eb4b6478aa30161866ccf9ce0ef5847c7 https://github.com/jeremyxu2010/sentinel.git diff --git a/vendor/github.com/FZambia/sentinel/LICENSE b/vendor/github.com/FZambia/sentinel/LICENSE new file mode 100644 index 0000000000..8dada3edaf --- /dev/null +++ b/vendor/github.com/FZambia/sentinel/LICENSE @@ -0,0 +1,201 @@ + Apache License + Version 2.0, January 2004 + http://www.apache.org/licenses/ + + TERMS AND CONDITIONS FOR USE, REPRODUCTION, AND DISTRIBUTION + + 1. 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We also recommend that a + file or class name and description of purpose be included on the + same "printed page" as the copyright notice for easier + identification within third-party archives. + + Copyright {yyyy} {name of copyright owner} + + Licensed under the Apache License, Version 2.0 (the "License"); + you may not use this file except in compliance with the License. + You may obtain a copy of the License at + + http://www.apache.org/licenses/LICENSE-2.0 + + Unless required by applicable law or agreed to in writing, software + distributed under the License is distributed on an "AS IS" BASIS, + WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. + See the License for the specific language governing permissions and + limitations under the License. diff --git a/vendor/github.com/FZambia/sentinel/README.md b/vendor/github.com/FZambia/sentinel/README.md new file mode 100644 index 0000000000..f544c54ef6 --- /dev/null +++ b/vendor/github.com/FZambia/sentinel/README.md @@ -0,0 +1,39 @@ +go-sentinel +=========== + +Redis Sentinel support for [redigo](https://github.com/gomodule/redigo) library. + +Documentation +------------- + +- [API Reference](http://godoc.org/github.com/FZambia/sentinel) + +Alternative solution +-------------------- + +You can alternatively configure Haproxy between your application and Redis to proxy requests to Redis master instance if you only need HA: + +``` +listen redis + server redis-01 127.0.0.1:6380 check port 6380 check inter 2s weight 1 inter 2s downinter 5s rise 10 fall 2 + server redis-02 127.0.0.1:6381 check port 6381 check inter 2s weight 1 inter 2s downinter 5s rise 10 fall 2 backup + bind *:6379 + mode tcp + option tcpka + option tcplog + option tcp-check + tcp-check send PING\r\n + tcp-check expect string +PONG + tcp-check send info\ replication\r\n + tcp-check expect string role:master + tcp-check send QUIT\r\n + tcp-check expect string +OK + balance roundrobin +``` + +This way you don't need to use this library. + +License +------- + +Library is available under the [Apache License, Version 2.0](http://www.apache.org/licenses/LICENSE-2.0.html). diff --git a/vendor/github.com/FZambia/sentinel/sentinel.go b/vendor/github.com/FZambia/sentinel/sentinel.go new file mode 100644 index 0000000000..79209e9f0d --- /dev/null +++ b/vendor/github.com/FZambia/sentinel/sentinel.go @@ -0,0 +1,426 @@ +package sentinel + +import ( + "errors" + "fmt" + "net" + "strings" + "sync" + "time" + + "github.com/garyburd/redigo/redis" +) + +// Sentinel provides a way to add high availability (HA) to Redis Pool using +// preconfigured addresses of Sentinel servers and name of master which Sentinels +// monitor. It works with Redis >= 2.8.12 (mostly because of ROLE command that +// was introduced in that version, it's possible though to support old versions +// using INFO command). +// +// Example of the simplest usage to contact master "mymaster": +// +// func newSentinelPool() *redis.Pool { +// sntnl := &sentinel.Sentinel{ +// Addrs: []string{":26379", ":26380", ":26381"}, +// MasterName: "mymaster", +// Dial: func(addr string) (redis.Conn, error) { +// timeout := 500 * time.Millisecond +// c, err := redis.DialTimeout("tcp", addr, timeout, timeout, timeout) +// if err != nil { +// return nil, err +// } +// return c, nil +// }, +// } +// return &redis.Pool{ +// MaxIdle: 3, +// MaxActive: 64, +// Wait: true, +// IdleTimeout: 240 * time.Second, +// Dial: func() (redis.Conn, error) { +// masterAddr, err := sntnl.MasterAddr() +// if err != nil { +// return nil, err +// } +// c, err := redis.Dial("tcp", masterAddr) +// if err != nil { +// return nil, err +// } +// return c, nil +// }, +// TestOnBorrow: func(c redis.Conn, t time.Time) error { +// if !sentinel.TestRole(c, "master") { +// return errors.New("Role check failed") +// } else { +// return nil +// } +// }, +// } +// } +type Sentinel struct { + // Addrs is a slice with known Sentinel addresses. + Addrs []string + + // MasterName is a name of Redis master Sentinel servers monitor. + MasterName string + + // Dial is a user supplied function to connect to Sentinel on given address. This + // address will be chosen from Addrs slice. + // Note that as per the redis-sentinel client guidelines, a timeout is mandatory + // while connecting to Sentinels, and should not be set to 0. + Dial func(addr string) (redis.Conn, error) + + // Pool is a user supplied function returning custom connection pool to Sentinel. + // This can be useful to tune options if you are not satisfied with what default + // Sentinel pool offers. See defaultPool() method for default pool implementation. + // In most cases you only need to provide Dial function and let this be nil. + Pool func(addr string) *redis.Pool + + mu sync.RWMutex + pools map[string]*redis.Pool + addr string +} + +// NoSentinelsAvailable is returned when all sentinels in the list are exhausted +// (or none configured), and contains the last error returned by Dial (which +// may be nil) +type NoSentinelsAvailable struct { + lastError error +} + +func (ns NoSentinelsAvailable) Error() string { + if ns.lastError != nil { + return fmt.Sprintf("redigo: no sentinels available; last error: %s", ns.lastError.Error()) + } + return fmt.Sprintf("redigo: no sentinels available") +} + +// putToTop puts Sentinel address to the top of address list - this means +// that all next requests will use Sentinel on this address first. +// +// From Sentinel guidelines: +// +// The first Sentinel replying to the client request should be put at the +// start of the list, so that at the next reconnection, we'll try first +// the Sentinel that was reachable in the previous connection attempt, +// minimizing latency. +// +// Lock must be held by caller. +func (s *Sentinel) putToTop(addr string) { + addrs := s.Addrs + if addrs[0] == addr { + // Already on top. + return + } + newAddrs := []string{addr} + for _, a := range addrs { + if a == addr { + continue + } + newAddrs = append(newAddrs, a) + } + s.Addrs = newAddrs +} + +// putToBottom puts Sentinel address to the bottom of address list. +// We call this method internally when see that some Sentinel failed to answer +// on application request so next time we start with another one. +// +// Lock must be held by caller. +func (s *Sentinel) putToBottom(addr string) { + addrs := s.Addrs + if addrs[len(addrs)-1] == addr { + // Already on bottom. + return + } + newAddrs := []string{} + for _, a := range addrs { + if a == addr { + continue + } + newAddrs = append(newAddrs, a) + } + newAddrs = append(newAddrs, addr) + s.Addrs = newAddrs +} + +// defaultPool returns a connection pool to one Sentinel. This allows +// us to call concurrent requests to Sentinel using connection Do method. +func (s *Sentinel) defaultPool(addr string) *redis.Pool { + return &redis.Pool{ + MaxIdle: 3, + MaxActive: 10, + Wait: true, + IdleTimeout: 240 * time.Second, + Dial: func() (redis.Conn, error) { + return s.Dial(addr) + }, + TestOnBorrow: func(c redis.Conn, t time.Time) error { + _, err := c.Do("PING") + return err + }, + } +} + +func (s *Sentinel) get(addr string) redis.Conn { + pool := s.poolForAddr(addr) + return pool.Get() +} + +func (s *Sentinel) poolForAddr(addr string) *redis.Pool { + s.mu.Lock() + if s.pools == nil { + s.pools = make(map[string]*redis.Pool) + } + pool, ok := s.pools[addr] + if ok { + s.mu.Unlock() + return pool + } + s.mu.Unlock() + newPool := s.newPool(addr) + s.mu.Lock() + p, ok := s.pools[addr] + if ok { + s.mu.Unlock() + return p + } + s.pools[addr] = newPool + s.mu.Unlock() + return newPool +} + +func (s *Sentinel) newPool(addr string) *redis.Pool { + if s.Pool != nil { + return s.Pool(addr) + } + return s.defaultPool(addr) +} + +// close connection pool to Sentinel. +// Lock must be hold by caller. +func (s *Sentinel) close() { + if s.pools != nil { + for _, pool := range s.pools { + pool.Close() + } + } + s.pools = nil +} + +func (s *Sentinel) doUntilSuccess(f func(redis.Conn) (interface{}, error)) (interface{}, error) { + s.mu.RLock() + addrs := s.Addrs + s.mu.RUnlock() + + var lastErr error + + for _, addr := range addrs { + conn := s.get(addr) + reply, err := f(conn) + conn.Close() + if err != nil { + lastErr = err + s.mu.Lock() + pool, ok := s.pools[addr] + if ok { + pool.Close() + delete(s.pools, addr) + } + s.putToBottom(addr) + s.mu.Unlock() + continue + } + s.putToTop(addr) + return reply, nil + } + + return nil, NoSentinelsAvailable{lastError: lastErr} +} + +// MasterAddr returns an address of current Redis master instance. +func (s *Sentinel) MasterAddr() (string, error) { + res, err := s.doUntilSuccess(func(c redis.Conn) (interface{}, error) { + return queryForMaster(c, s.MasterName) + }) + if err != nil { + return "", err + } + return res.(string), nil +} + +// SlaveAddrs returns a slice with known slave addresses of current master instance. +func (s *Sentinel) SlaveAddrs() ([]string, error) { + res, err := s.doUntilSuccess(func(c redis.Conn) (interface{}, error) { + return queryForSlaveAddrs(c, s.MasterName) + }) + if err != nil { + return nil, err + } + return res.([]string), nil +} + +// Slave represents a Redis slave instance which is known by Sentinel. +type Slave struct { + ip string + port string + flags string +} + +// Addr returns an address of slave. +func (s *Slave) Addr() string { + return net.JoinHostPort(s.ip, s.port) +} + +// Available returns if slave is in working state at moment based on information in slave flags. +func (s *Slave) Available() bool { + return !strings.Contains(s.flags, "disconnected") && !strings.Contains(s.flags, "s_down") +} + +// Slaves returns a slice with known slaves of master instance. +func (s *Sentinel) Slaves() ([]*Slave, error) { + res, err := s.doUntilSuccess(func(c redis.Conn) (interface{}, error) { + return queryForSlaves(c, s.MasterName) + }) + if err != nil { + return nil, err + } + return res.([]*Slave), nil +} + +// SentinelAddrs returns a slice of known Sentinel addresses Sentinel server aware of. +func (s *Sentinel) SentinelAddrs() ([]string, error) { + res, err := s.doUntilSuccess(func(c redis.Conn) (interface{}, error) { + return queryForSentinels(c, s.MasterName) + }) + if err != nil { + return nil, err + } + return res.([]string), nil +} + +// Discover allows to update list of known Sentinel addresses. From docs: +// +// A client may update its internal list of Sentinel nodes following this procedure: +// 1) Obtain a list of other Sentinels for this master using the command SENTINEL sentinels . +// 2) Add every ip:port pair not already existing in our list at the end of the list. +func (s *Sentinel) Discover() error { + addrs, err := s.SentinelAddrs() + if err != nil { + return err + } + s.mu.Lock() + for _, addr := range addrs { + if !stringInSlice(addr, s.Addrs) { + s.Addrs = append(s.Addrs, addr) + } + } + s.mu.Unlock() + return nil +} + +// Close closes current connection to Sentinel. +func (s *Sentinel) Close() error { + s.mu.Lock() + s.close() + s.mu.Unlock() + return nil +} + +// TestRole wraps GetRole in a test to verify if the role matches an expected +// role string. If there was any error in querying the supplied connection, +// the function returns false. Works with Redis >= 2.8.12. +// It's not goroutine safe, but if you call this method on pooled connections +// then you are OK. +func TestRole(c redis.Conn, expectedRole string) bool { + role, err := getRole(c) + if err != nil || role != expectedRole { + return false + } + return true +} + +// getRole is a convenience function supplied to query an instance (master or +// slave) for its role. It attempts to use the ROLE command introduced in +// redis 2.8.12. +func getRole(c redis.Conn) (string, error) { + res, err := c.Do("ROLE") + if err != nil { + return "", err + } + rres, ok := res.([]interface{}) + if ok { + return redis.String(rres[0], nil) + } + return "", errors.New("redigo: can not transform ROLE reply to string") +} + +func queryForMaster(conn redis.Conn, masterName string) (string, error) { + res, err := redis.Strings(conn.Do("SENTINEL", "get-master-addr-by-name", masterName)) + if err != nil { + return "", err + } + if len(res) < 2 { + return "", errors.New("redigo: malformed get-master-addr-by-name reply") + } + masterAddr := net.JoinHostPort(res[0], res[1]) + return masterAddr, nil +} + +func queryForSlaveAddrs(conn redis.Conn, masterName string) ([]string, error) { + slaves, err := queryForSlaves(conn, masterName) + if err != nil { + return nil, err + } + slaveAddrs := make([]string, 0) + for _, slave := range slaves { + slaveAddrs = append(slaveAddrs, slave.Addr()) + } + return slaveAddrs, nil +} + +func queryForSlaves(conn redis.Conn, masterName string) ([]*Slave, error) { + res, err := redis.Values(conn.Do("SENTINEL", "slaves", masterName)) + if err != nil { + return nil, err + } + slaves := make([]*Slave, 0) + for _, a := range res { + sm, err := redis.StringMap(a, err) + if err != nil { + return slaves, err + } + slave := &Slave{ + ip: sm["ip"], + port: sm["port"], + flags: sm["flags"], + } + slaves = append(slaves, slave) + } + return slaves, nil +} + +func queryForSentinels(conn redis.Conn, masterName string) ([]string, error) { + res, err := redis.Values(conn.Do("SENTINEL", "sentinels", masterName)) + if err != nil { + return nil, err + } + sentinels := make([]string, 0) + for _, a := range res { + sm, err := redis.StringMap(a, err) + if err != nil { + return sentinels, err + } + sentinels = append(sentinels, fmt.Sprintf("%s:%s", sm["ip"], sm["port"])) + } + return sentinels, nil +} + +func stringInSlice(str string, slice []string) bool { + for _, s := range slice { + if s == str { + return true + } + } + return false +}