Remove broken Workhorse Redis settings

This removes the following Redis config settings from Workhorse:

- KeepAlivePeriod
- ReadTimeout
- WriteTimeout

These settings have been broken for 4 years (since
0e777472). If you tried
setting them in config.toml, Workhorse would fail to start up.

Because this is a major failure (failing to start) and no-one has
fixed it after 4 years I think we can conclude nobody uses these
settings and we can remove them.

workhorse/doc/operations/configuration.md

@@ -103,15 +103,11 @@ Optional fields are as follows:
 ```
 [redis]
 DB = 0
-ReadTimeout = "1s"
-KeepAlivePeriod = "5m"
 MaxIdle = 1
 MaxActive = 1
 ```
 
 - `DB` is the Database to connect to. Defaults to `0`
-- `ReadTimeout` is how long a redis read-command can take. Defaults to `1s`
-- `KeepAlivePeriod` is how long the redis connection is to be kept alive without anything flowing through it. Defaults to `5m`
 - `MaxIdle` is how many idle connections can be in the redis-pool at once. Defaults to 1
 - `MaxActive` is how many connections the pool can keep. Defaults to 1
 

workhorse/internal/config/config.go

@@ -70,16 +70,13 @@ type AzureCredentials struct {
 }
 
 type RedisConfig struct {
-	URL             TomlURL
-	Sentinel        []TomlURL
-	SentinelMaster  string
-	Password        string
-	DB              *int
-	ReadTimeout     *TomlDuration
-	WriteTimeout    *TomlDuration
-	KeepAlivePeriod *TomlDuration
-	MaxIdle         *int
-	MaxActive       *int
+	URL            TomlURL
+	Sentinel       []TomlURL
+	SentinelMaster string
+	Password       string
+	DB             *int
+	MaxIdle        *int
+	MaxActive      *int
 }
 
 type ImageResizerConfig struct {

workhorse/internal/redis/redis.go

@@ -113,21 +113,9 @@ var poolDialFunc func() (redis.Conn, error)
 var workerDialFunc func() (redis.Conn, error)
 
 func timeoutDialOptions(cfg *config.RedisConfig) []redis.DialOption {
-	readTimeout := defaultReadTimeout
-	writeTimeout := defaultWriteTimeout
-
-	if cfg != nil {
-		if cfg.ReadTimeout != nil {
-			readTimeout = cfg.ReadTimeout.Duration
-		}
-
-		if cfg.WriteTimeout != nil {
-			writeTimeout = cfg.WriteTimeout.Duration
-		}
-	}
 	return []redis.DialOption{
-		redis.DialReadTimeout(readTimeout),
-		redis.DialWriteTimeout(writeTimeout),
+		redis.DialReadTimeout(defaultReadTimeout),
+		redis.DialWriteTimeout(defaultWriteTimeout),
 	}
 }
 
@@ -148,47 +136,45 @@ func dialOptionsBuilder(cfg *config.RedisConfig, setTimeouts bool) []redis.DialO
 	return dopts
 }
 
-func keepAliveDialer(timeout time.Duration) func(string, string) (net.Conn, error) {
-	return func(network, address string) (net.Conn, error) {
-		addr, err := net.ResolveTCPAddr(network, address)
-		if err != nil {
-			return nil, err
-		}
-		tc, err := net.DialTCP(network, nil, addr)
-		if err != nil {
-			return nil, err
-		}
-		if err := tc.SetKeepAlive(true); err != nil {
-			return nil, err
-		}
-		if err := tc.SetKeepAlivePeriod(timeout); err != nil {
-			return nil, err
-		}
-		return tc, nil
+func keepAliveDialer(network, address string) (net.Conn, error) {
+	addr, err := net.ResolveTCPAddr(network, address)
+	if err != nil {
+		return nil, err
 	}
+	tc, err := net.DialTCP(network, nil, addr)
+	if err != nil {
+		return nil, err
+	}
+	if err := tc.SetKeepAlive(true); err != nil {
+		return nil, err
+	}
+	if err := tc.SetKeepAlivePeriod(defaultKeepAlivePeriod); err != nil {
+		return nil, err
+	}
+	return tc, nil
 }
 
 type redisDialerFunc func() (redis.Conn, error)
 
-func sentinelDialer(dopts []redis.DialOption, keepAlivePeriod time.Duration) redisDialerFunc {
+func sentinelDialer(dopts []redis.DialOption) redisDialerFunc {
 	return func() (redis.Conn, error) {
 		address, err := sntnl.MasterAddr()
 		if err != nil {
 			errorCounter.WithLabelValues("master", "sentinel").Inc()
 			return nil, err
 		}
-		dopts = append(dopts, redis.DialNetDial(keepAliveDialer(keepAlivePeriod)))
+		dopts = append(dopts, redis.DialNetDial(keepAliveDialer))
 		return redisDial("tcp", address, dopts...)
 	}
 }
 
-func defaultDialer(dopts []redis.DialOption, keepAlivePeriod time.Duration, url url.URL) redisDialerFunc {
+func defaultDialer(dopts []redis.DialOption, url url.URL) redisDialerFunc {
 	return func() (redis.Conn, error) {
 		if url.Scheme == "unix" {
 			return redisDial(url.Scheme, url.Path, dopts...)
 		}
 
-		dopts = append(dopts, redis.DialNetDial(keepAliveDialer(keepAlivePeriod)))
+		dopts = append(dopts, redis.DialNetDial(keepAliveDialer))
 
 		// redis.DialURL only works with redis[s]:// URLs
 		if url.Scheme == "redis" || url.Scheme == "rediss" {
@@ -231,15 +217,11 @@ func countDialer(dialer redisDialerFunc) redisDialerFunc {
 
 // DefaultDialFunc should always used. Only exception is for unit-tests.
 func DefaultDialFunc(cfg *config.RedisConfig, setReadTimeout bool) func() (redis.Conn, error) {
-	keepAlivePeriod := defaultKeepAlivePeriod
-	if cfg.KeepAlivePeriod != nil {
-		keepAlivePeriod = cfg.KeepAlivePeriod.Duration
-	}
 	dopts := dialOptionsBuilder(cfg, setReadTimeout)
 	if sntnl != nil {
-		return countDialer(sentinelDialer(dopts, keepAlivePeriod))
+		return countDialer(sentinelDialer(dopts))
 	}
-	return countDialer(defaultDialer(dopts, keepAlivePeriod, cfg.URL.URL))
+	return countDialer(defaultDialer(dopts, cfg.URL.URL))
 }
 
 // Configure redis-connection

workhorse/internal/redis/redis_test.go

@@ -96,13 +96,11 @@ func TestConfigureMinimalConfig(t *testing.T) {
 
 func TestConfigureFullConfig(t *testing.T) {
 	i, a := 4, 10
-	r := config.TomlDuration{Duration: 3}
 	cfg := &config.RedisConfig{
-		URL:         config.TomlURL{},
-		Password:    "",
-		MaxIdle:     &i,
-		MaxActive:   &a,
-		ReadTimeout: &r,
+		URL:       config.TomlURL{},
+		Password:  "",
+		MaxIdle:   &i,
+		MaxActive: &a,
 	}
 	Configure(cfg, DefaultDialFunc)
 
@@ -219,11 +217,7 @@ func TestDialOptionsBuildersSetTimeouts(t *testing.T) {
 }
 
 func TestDialOptionsBuildersSetTimeoutsConfig(t *testing.T) {
-	cfg := &config.RedisConfig{
-		ReadTimeout:  &config.TomlDuration{Duration: time.Second * time.Duration(15)},
-		WriteTimeout: &config.TomlDuration{Duration: time.Second * time.Duration(15)},
-	}
-	dopts := dialOptionsBuilder(cfg, true)
+	dopts := dialOptionsBuilder(nil, true)
 	require.Equal(t, 2, len(dopts))
 }