From 10cc50ad2939d213e293c081137d893b2efee9cf Mon Sep 17 00:00:00 2001
From: capone <anzor.apshev@gmail.com>
Date: Tue, 23 Aug 2016 19:09:20 +0300
Subject: [PATCH 1/2] First attemt to fix issue #1636

---
 command/agent/consul/check.go  |  6 ++++++
 command/agent/consul/syncer.go | 19 ++++++++++++++++++-
 2 files changed, 24 insertions(+), 1 deletion(-)

diff --git a/command/agent/consul/check.go b/command/agent/consul/check.go
index 28df291f6..1b601ea36 100644
--- a/command/agent/consul/check.go
+++ b/command/agent/consul/check.go
@@ -47,6 +47,12 @@ func (r *CheckRunner) Start() {
 	r.started = true
 }
 
+func (r *CheckRunner) Started() bool {
+	r.startedLock.Lock()
+	defer r.startedLock.Unlock()
+	return r.started
+}
+
 // Stop is used to stop the check.
 func (r *CheckRunner) Stop() {
 	r.stopLock.Lock()
diff --git a/command/agent/consul/syncer.go b/command/agent/consul/syncer.go
index 736e15c8e..f7d78f7ef 100644
--- a/command/agent/consul/syncer.go
+++ b/command/agent/consul/syncer.go
@@ -394,7 +394,7 @@ func (c *Syncer) syncChecks() error {
 	}
 
 	// Synchronize checks with Consul
-	missingChecks, _, changedChecks, staleChecks := c.calcChecksDiff(consulChecks)
+	missingChecks, existingChecks, changedChecks, staleChecks := c.calcChecksDiff(consulChecks)
 	for _, check := range missingChecks {
 		if err := c.registerCheck(check); err != nil {
 			mErr.Errors = append(mErr.Errors, err)
@@ -403,6 +403,9 @@ func (c *Syncer) syncChecks() error {
 		c.trackedChecks[consulCheckID(check.ID)] = check
 		c.registryLock.Unlock()
 	}
+	for _, check := range existingChecks {
+		c.ensureCheckRunning(check)
+	}
 	for _, check := range changedChecks {
 		// NOTE(sean@): Do we need to deregister the check before
 		// re-registering it?  Not deregistering to avoid missing the
@@ -684,6 +687,20 @@ func (c *Syncer) registerCheck(chkReg *consul.AgentCheckRegistration) error {
 	return c.client.Agent().CheckRegister(chkReg)
 }
 
+// ensureCheckRunning verifies that registerd check is in running state
+func (c *Syncer) ensureCheckRunning(chk *consul.AgentCheckRegistration) {
+	c.registryLock.RLock()
+	defer c.registryLock.RUnlock()
+	cr, ok := c.checkRunners[consulCheckID(chk.ID)]
+	if !ok {
+		return
+	}
+	if !cr.Started() {
+		c.logger.Printf("[DEBUG] ensureCheckRunning Running existing check. %v", chk)
+		cr.Start()
+	}
+}
+
 // createCheckReg creates a Check that can be registered with Nomad. It also
 // creates a Nomad check for the check types that it can handle.
 func (c *Syncer) createCheckReg(check *structs.ServiceCheck, serviceReg *consul.AgentServiceRegistration) (*consul.AgentCheckRegistration, error) {

From ce4d236a4076f7d4b4e48aaa3485cbdcedc29c18 Mon Sep 17 00:00:00 2001
From: capone <anzor.apshev@gmail.com>
Date: Wed, 24 Aug 2016 01:33:44 +0300
Subject: [PATCH 2/2] Fixed CR defects

---
 command/agent/consul/check.go  |  1 +
 command/agent/consul/syncer.go | 10 +++-------
 2 files changed, 4 insertions(+), 7 deletions(-)

diff --git a/command/agent/consul/check.go b/command/agent/consul/check.go
index 1b601ea36..551f94b6f 100644
--- a/command/agent/consul/check.go
+++ b/command/agent/consul/check.go
@@ -47,6 +47,7 @@ func (r *CheckRunner) Start() {
 	r.started = true
 }
 
+// Started returns if the check runner has started running
 func (r *CheckRunner) Started() bool {
 	r.startedLock.Lock()
 	defer r.startedLock.Unlock()
diff --git a/command/agent/consul/syncer.go b/command/agent/consul/syncer.go
index f7d78f7ef..8ac66fd9f 100644
--- a/command/agent/consul/syncer.go
+++ b/command/agent/consul/syncer.go
@@ -687,16 +687,12 @@ func (c *Syncer) registerCheck(chkReg *consul.AgentCheckRegistration) error {
 	return c.client.Agent().CheckRegister(chkReg)
 }
 
-// ensureCheckRunning verifies that registerd check is in running state
+// ensureCheckRunning starts the check runner for a check if it's not already running
 func (c *Syncer) ensureCheckRunning(chk *consul.AgentCheckRegistration) {
 	c.registryLock.RLock()
 	defer c.registryLock.RUnlock()
-	cr, ok := c.checkRunners[consulCheckID(chk.ID)]
-	if !ok {
-		return
-	}
-	if !cr.Started() {
-		c.logger.Printf("[DEBUG] ensureCheckRunning Running existing check. %v", chk)
+	if cr, ok := c.checkRunners[consulCheckID(chk.ID)]; ok && !cr.Started() {
+		c.logger.Printf("[DEBUG] consul.syncer: starting runner for existing check. %v", chk.ID)
 		cr.Start()
 	}
 }