Pass context to WaitReady of alertmanager Peer interface. (cortexproject#3931)

* Update alertmanager.

Signed-off-by: Steve Simpson <steve.simpson@grafana.com>

* Pass context to WaitReady of alertmanager Peer interface.

Signed-off-by: Steve Simpson <steve.simpson@grafana.com>

Author: stevesg

go.mod

@@ -43,7 +43,7 @@ require (
 	github.com/opentracing-contrib/go-stdlib v1.0.0
 	github.com/opentracing/opentracing-go v1.2.0
 	github.com/pkg/errors v0.9.1
-	github.com/prometheus/alertmanager v0.21.1-0.20210303154452-7866b9bb0927
+	github.com/prometheus/alertmanager v0.21.1-0.20210310093010-0f9cab6991e6
 	github.com/prometheus/client_golang v1.9.0
 	github.com/prometheus/client_model v0.2.0
 	github.com/prometheus/common v0.18.0

go.sum

@@ -1037,8 +1037,8 @@ github.com/prometheus/alertmanager v0.21.0/go.mod h1:h7tJ81NA0VLWvWEayi1QltevFkL
 github.com/prometheus/alertmanager v0.21.1-0.20200911160112-1fdff6b3f939/go.mod h1:imXRHOP6QTsE0fFsIsAV/cXimS32m7gVZOiUj11m6Ig=
 github.com/prometheus/alertmanager v0.21.1-0.20201106142418-c39b78780054 h1:NgCRBfzDpyIhX6Pjh7XSWPHUC8T5dA1yVuK/gwXM7Jw=
 github.com/prometheus/alertmanager v0.21.1-0.20201106142418-c39b78780054/go.mod h1:imXRHOP6QTsE0fFsIsAV/cXimS32m7gVZOiUj11m6Ig=
-github.com/prometheus/alertmanager v0.21.1-0.20210303154452-7866b9bb0927 h1:BLdqq8kRvpCWghcXjU32mi4pzJlyo8InM5hfmIqFyoc=
-github.com/prometheus/alertmanager v0.21.1-0.20210303154452-7866b9bb0927/go.mod h1:MTqVn+vIupE0dzdgo+sMcNCp37SCAi8vPrvKTTnTz9g=
+github.com/prometheus/alertmanager v0.21.1-0.20210310093010-0f9cab6991e6 h1:WeazuhFA+g8Xce5wgqskDP+b48oQKk7smH72dxO2beA=
+github.com/prometheus/alertmanager v0.21.1-0.20210310093010-0f9cab6991e6/go.mod h1:MTqVn+vIupE0dzdgo+sMcNCp37SCAi8vPrvKTTnTz9g=
 github.com/prometheus/client_golang v0.8.0/go.mod h1:7SWBe2y4D6OKWSNQJUaRYU/AaXPKyh/dDVn+NZz0KFw=
 github.com/prometheus/client_golang v0.9.1/go.mod h1:7SWBe2y4D6OKWSNQJUaRYU/AaXPKyh/dDVn+NZz0KFw=
 github.com/prometheus/client_golang v0.9.2/go.mod h1:OsXs2jCmiKlQ1lTBmv21f2mNfw4xf/QclQDMrYNZzcM=

pkg/alertmanager/alertmanager.go

@@ -113,7 +113,7 @@ func init() {
 type State interface {
 	AddState(string, cluster.State, prometheus.Registerer) cluster.ClusterChannel
 	Position() int
-	WaitReady()
+	WaitReady(context.Context) error
 }
 
 // New creates a new Alertmanager.
@@ -426,11 +426,11 @@ func md5HashAsMetricValue(data []byte) float64 {
 // In a multi-tenant environment, we choose not to expose these to tenants and thus are not implemented.
 type NilPeer struct{}
 
-func (p *NilPeer) Name() string                   { return "" }
-func (p *NilPeer) Status() string                 { return "ready" }
-func (p *NilPeer) Peers() []cluster.ClusterMember { return nil }
-func (p *NilPeer) Position() int                  { return 0 }
-func (p *NilPeer) WaitReady()                     {}
+func (p *NilPeer) Name() string                    { return "" }
+func (p *NilPeer) Status() string                  { return "ready" }
+func (p *NilPeer) Peers() []cluster.ClusterMember  { return nil }
+func (p *NilPeer) Position() int                   { return 0 }
+func (p *NilPeer) WaitReady(context.Context) error { return nil }
 func (p *NilPeer) AddState(string, cluster.State, prometheus.Registerer) cluster.ClusterChannel {
 	return &NilChannel{}
 }

pkg/alertmanager/state_replication.go

@@ -129,11 +129,17 @@ func (s *state) Settle(ctx context.Context, _ time.Duration) {
 }
 
 // WaitReady is needed for the pipeline builder to know whenever we've settled and the state is up to date.
-func (s *state) WaitReady() {
+func (s *state) WaitReady(ctx context.Context) error {
 	//TODO: At the moment, we settle in a separate go-routine (see multitenant.go as we create the Peer) we should
 	// mimic that behaviour here once we have full state replication.
-	s.Settle(context.Background(), time.Second)
-	<-s.readyc
+	s.Settle(ctx, time.Second)
+
+	select {
+	case <-ctx.Done():
+		return ctx.Err()
+	case <-s.readyc:
+		return nil
+	}
 }
 
 func (s *state) Ready() bool {