Add DeregisterCriticalServiceAfter to Consul checks

Consul can automatically deregister services if the health check is critical for a given amount of time. This is useful if fabio exits abnormally without deregistering services.
fabiolb · Feb 7, 2018 · 9ece33a · 9ece33a
1 parent dc1cd89
commit 9ece33a
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Showing 5 changed files with 49 additions and 32 deletions.
diff --git a/config/config.go b/config/config.go
@@ -126,19 +126,20 @@ type File struct {
 }
 
 type Consul struct {
-	Addr               string
-	Scheme             string
-	Token              string
-	KVPath             string
-	NoRouteHTMLPath    string
-	TagPrefix          string
-	Register           bool
-	ServiceAddr        string
-	ServiceName        string
-	ServiceTags        []string
-	ServiceStatus      []string
-	CheckInterval      time.Duration
-	CheckTimeout       time.Duration
-	CheckScheme        string
-	CheckTLSSkipVerify bool
+	Addr                                string
+	Scheme                              string
+	Token                               string
+	KVPath                              string
+	NoRouteHTMLPath                     string
+	TagPrefix                           string
+	Register                            bool
+	ServiceAddr                         string
+	ServiceName                         string
+	ServiceTags                         []string
+	ServiceStatus                       []string
+	CheckInterval                       time.Duration
+	CheckTimeout                        time.Duration
+	CheckScheme                         string
+	CheckTLSSkipVerify                  bool
+	CheckDeregisterCriticalServiceAfter string
 }
diff --git a/config/default.go b/config/default.go
@@ -47,18 +47,19 @@ var defaultConfig = &Config{
 	Registry: Registry{
 		Backend: "consul",
 		Consul: Consul{
-			Addr:            "localhost:8500",
-			Scheme:          "http",
-			KVPath:          "/fabio/config",
-			NoRouteHTMLPath: "/fabio/noroute.html",
-			TagPrefix:       "urlprefix-",
-			Register:        true,
-			ServiceAddr:     ":9998",
-			ServiceName:     "fabio",
-			ServiceStatus:   []string{"passing"},
-			CheckInterval:   time.Second,
-			CheckTimeout:    3 * time.Second,
-			CheckScheme:     "http",
+			Addr:                                "localhost:8500",
+			Scheme:                              "http",
+			KVPath:                              "/fabio/config",
+			NoRouteHTMLPath:                     "/fabio/noroute.html",
+			TagPrefix:                           "urlprefix-",
+			Register:                            true,
+			ServiceAddr:                         ":9998",
+			ServiceName:                         "fabio",
+			ServiceStatus:                       []string{"passing"},
+			CheckInterval:                       time.Second,
+			CheckTimeout:                        3 * time.Second,
+			CheckScheme:                         "http",
+			CheckDeregisterCriticalServiceAfter: "90m",
 		},
 		Timeout: 10 * time.Second,
 		Retry:   500 * time.Millisecond,

diff --git a/config/load.go b/config/load.go
@@ -175,7 +175,8 @@ func load(cmdline, environ, envprefix []string, props *properties.Properties) (c
 	f.StringSliceVar(&cfg.Registry.Consul.ServiceStatus, "registry.consul.service.status", defaultConfig.Registry.Consul.ServiceStatus, "valid service status values")
 	f.DurationVar(&cfg.Registry.Consul.CheckInterval, "registry.consul.register.checkInterval", defaultConfig.Registry.Consul.CheckInterval, "service check interval")
 	f.DurationVar(&cfg.Registry.Consul.CheckTimeout, "registry.consul.register.checkTimeout", defaultConfig.Registry.Consul.CheckTimeout, "service check timeout")
-	f.BoolVar(&cfg.Registry.Consul.CheckTLSSkipVerify, "registry.consul.register.checkTLSSkipVerify", defaultConfig.Registry.Consul.CheckTLSSkipVerify, "service check TLS verifcation")
+	f.BoolVar(&cfg.Registry.Consul.CheckTLSSkipVerify, "registry.consul.register.checkTLSSkipVerify", defaultConfig.Registry.Consul.CheckTLSSkipVerify, "service check TLS verification")
+	f.StringVar(&cfg.Registry.Consul.CheckDeregisterCriticalServiceAfter, "registry.consul.register.checkDeregisterCriticalServiceAfter", defaultConfig.Registry.Consul.CheckDeregisterCriticalServiceAfter, "critical service deregistration timeout")
 	f.IntVar(&cfg.Runtime.GOGC, "runtime.gogc", defaultConfig.Runtime.GOGC, "sets runtime.GOGC")
 	f.IntVar(&cfg.Runtime.GOMAXPROCS, "runtime.gomaxprocs", defaultConfig.Runtime.GOMAXPROCS, "sets runtime.GOMAXPROCS")
 	f.StringVar(&cfg.UI.Access, "ui.access", defaultConfig.UI.Access, "access mode, one of [ro, rw]")

diff --git a/fabio.properties b/fabio.properties
@@ -718,6 +718,19 @@
 # registry.consul.register.checkTLSSkipVerify = false
 
 
+# registry.consul.register.checkDeregisterCriticalServiceAfter configures
+# automatic deregistration of a service after the health check is critical for
+# this length of time.
+#
+# Fabio registers an http health check on http(s)://${ui.addr}/health
+# and this value tells consul to deregister the associated service if the check
+# is critical for the specified duration.
+#
+# The default is
+#
+# registry.consul.register.checkDeregisterCriticalServiceAfter = 90m
+
+
 # metrics.target configures the backend the metrics values are
 # sent to.
 #

diff --git a/registry/consul/register.go b/registry/consul/register.go
@@ -116,10 +116,11 @@ func serviceRegistration(cfg *config.Consul, serviceName string) (*api.AgentServ
 		Port:    port,
 		Tags:    cfg.ServiceTags,
 		Check: &api.AgentServiceCheck{
-			HTTP:          checkURL,
-			Interval:      cfg.CheckInterval.String(),
-			Timeout:       cfg.CheckTimeout.String(),
-			TLSSkipVerify: cfg.CheckTLSSkipVerify,
+			HTTP:                           checkURL,
+			Interval:                       cfg.CheckInterval.String(),
+			Timeout:                        cfg.CheckTimeout.String(),
+			TLSSkipVerify:                  cfg.CheckTLSSkipVerify,
+			DeregisterCriticalServiceAfter: cfg.CheckDeregisterCriticalServiceAfter,
 		},
 	}