Backports and skip tracing (#959)

* Update pingsource-mt-adapter.yaml

* Like on 0.18.3, we skip the tracing tests

Signed-off-by: Matthias Wessendorf <mwessend@redhat.com>

* [release-0.18] Retry on network failures (knative#4454) (knative#4457)

* Retry on network failures (knative#4454)

Signed-off-by: Pierangelo Di Pilato <pierangelodipilato@gmail.com>

* nethttp -> http

Signed-off-by: Pierangelo Di Pilato <pierangelodipilato@gmail.com>

* Backport knative#4465 (knative#4468)

Signed-off-by: Francesco Guardiani <francescoguard@gmail.com>

* [0.18] Backport knative#4466 (knative#4471)

* Remove double invocations to responseWriter.WriteHeader in filter handler (knative#4466)

* Fix knative#4464

Signed-off-by: Francesco Guardiani <francescoguard@gmail.com>

* Docs

Signed-off-by: Francesco Guardiani <francescoguard@gmail.com>

* Moar tests

Signed-off-by: Francesco Guardiani <francescoguard@gmail.com>

* Linting

Signed-off-by: Francesco Guardiani <francescoguard@gmail.com>

* Nit with metrics

Signed-off-by: Francesco Guardiani <francescoguard@gmail.com>

(cherry picked from commit a6fc540)
Signed-off-by: Francesco Guardiani <francescoguard@gmail.com>

* Nit

Signed-off-by: Francesco Guardiani <francescoguard@gmail.com>

* fixed wrong marshall in apiserversouece which will fix the missing ceOverrides extension  (knative#4477) (knative#4480)

* fixed wrong marshall

* fixed UT

* [0.18] Readyness probe in broker ingress (knative#4483)

* Fix knative#4473

Signed-off-by: Francesco Guardiani <francescoguard@gmail.com>

* Massage the filter yaml

Signed-off-by: Francesco Guardiani <francescoguard@gmail.com>

Co-authored-by: Matthias Wessendorf <mwessend@redhat.com>
Co-authored-by: Pierangelo Di Pilato <pierangelodipilato@gmail.com>
Co-authored-by: Francesco Guardiani <francescoguard@gmail.com>
Co-authored-by: capri-xiyue <52932582+capri-xiyue@users.noreply.github.com>

cmd/mtbroker/ingress/main.go

@@ -127,6 +127,7 @@ func main() {
 		MaxIdleConns:        defaultMaxIdleConnections,
 		MaxIdleConnsPerHost: defaultMaxIdleConnectionsPerHost,
 	}
+	kncloudevents.ConfigureConnectionArgs(&connectionArgs)
 	sender, err := kncloudevents.NewHttpMessageSender(&connectionArgs, "")
 	if err != nil {
 		logger.Fatal("Unable to create message sender", zap.Error(err))

config/brokers/mt-channel-broker/deployments/broker-filter.yaml

@@ -34,16 +34,18 @@ spec:
       - name: filter
         terminationMessagePolicy: FallbackToLogsOnError
         image: ko://knative.dev/eventing/cmd/mtbroker/filter
-        livenessProbe:
+        readinessProbe: &probe
           failureThreshold: 3
           httpGet:
             path: /healthz
             port: 8080
             scheme: HTTP
-          initialDelaySeconds: 5
           periodSeconds: 2
           successThreshold: 1
           timeoutSeconds: 1
+        livenessProbe:
+          <<: *probe
+          initialDelaySeconds: 5
         resources:
           requests:
             cpu: 100m

config/brokers/mt-channel-broker/deployments/broker-ingress.yaml

@@ -34,16 +34,18 @@ spec:
       - name: ingress
         terminationMessagePolicy: FallbackToLogsOnError
         image: ko://knative.dev/eventing/cmd/mtbroker/ingress
-        livenessProbe:
+        readinessProbe: &probe
           failureThreshold: 3
           httpGet:
             path: /healthz
             port: 8080
             scheme: HTTP
-          initialDelaySeconds: 5
           periodSeconds: 2
           successThreshold: 1
           timeoutSeconds: 1
+        livenessProbe:
+          <<: *probe
+          initialDelaySeconds: 5
         resources:
           requests:
             cpu: 100m

config/core/deployments/pingsource-mt-adapter.yaml

@@ -38,6 +38,7 @@ spec:
           image: ko://knative.dev/eventing/cmd/mtping
           env:
             - name: SYSTEM_NAMESPACE
+              value: ''
               valueFrom:
                 fieldRef:
                   apiVersion: v1

pkg/kncloudevents/http_client.go

@@ -0,0 +1,106 @@
+/*
+Copyright 2020 The Knative Authors
+
+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.
+*/
+
+package kncloudevents
+
+import (
+	nethttp "net/http"
+	"sync"
+	"time"
+
+	"go.opencensus.io/plugin/ochttp"
+	"knative.dev/pkg/tracing/propagation/tracecontextb3"
+)
+
+const (
+	defaultRetryWaitMin = 1 * time.Second
+	defaultRetryWaitMax = 30 * time.Second
+)
+
+type holder struct {
+	clientMutex    sync.Mutex
+	connectionArgs *ConnectionArgs
+	client         **nethttp.Client
+}
+
+var clientHolder = holder{}
+
+// The used HTTP client is a singleton, so the same http client is reused across all the application.
+// If connection args is modified, client is cleaned and a new one is created.
+func getClient() *nethttp.Client {
+	clientHolder.clientMutex.Lock()
+	defer clientHolder.clientMutex.Unlock()
+
+	if clientHolder.client == nil {
+		// Add connection options to the default transport.
+		var base = nethttp.DefaultTransport.(*nethttp.Transport).Clone()
+		clientHolder.connectionArgs.configureTransport(base)
+		c := &nethttp.Client{
+			// Add output tracing.
+			Transport: &ochttp.Transport{
+				Base:        base,
+				Propagation: tracecontextb3.TraceContextEgress,
+			},
+		}
+		clientHolder.client = &c
+	}
+
+	return *clientHolder.client
+}
+
+// ConfigureConnectionArgs configures the new connection args.
+// The existing client won't be affected, but a new one will be created.
+// Use sparingly, because it might lead to creating a lot of clients, none of them sharing their connection pool!
+func ConfigureConnectionArgs(ca *ConnectionArgs) {
+	clientHolder.clientMutex.Lock()
+	defer clientHolder.clientMutex.Unlock()
+
+	// Check if same config
+	if clientHolder.connectionArgs != nil &&
+		ca != nil &&
+		ca.MaxIdleConns == clientHolder.connectionArgs.MaxIdleConns &&
+		ca.MaxIdleConnsPerHost == clientHolder.connectionArgs.MaxIdleConnsPerHost {
+		return
+	}
+
+	if clientHolder.client != nil {
+		// Let's try to clean up a bit the existing client
+		// Note: this won't remove it nor close it
+		(*clientHolder.client).CloseIdleConnections()
+
+		// Setting client to nil
+		clientHolder.client = nil
+	}
+
+	clientHolder.connectionArgs = ca
+}
+
+// ConnectionArgs allow to configure connection parameters to the underlying
+// HTTP Client transport.
+type ConnectionArgs struct {
+	// MaxIdleConns refers to the max idle connections, as in net/http/transport.
+	MaxIdleConns int
+	// MaxIdleConnsPerHost refers to the max idle connections per host, as in net/http/transport.
+	MaxIdleConnsPerHost int
+}
+
+func (ca *ConnectionArgs) configureTransport(transport *nethttp.Transport) {
+	if ca == nil {
+		return
+	}
+	transport.MaxIdleConns = ca.MaxIdleConns
+	transport.MaxIdleConnsPerHost = ca.MaxIdleConnsPerHost
+}

pkg/kncloudevents/http_client_test.go

@@ -0,0 +1,72 @@
+/*
+Copyright 2020 The Knative Authors
+
+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.
+*/
+
+package kncloudevents
+
+import (
+	nethttp "net/http"
+	"testing"
+
+	"github.com/stretchr/testify/require"
+	"go.opencensus.io/plugin/ochttp"
+)
+
+func TestConfigureConnectionArgs(t *testing.T) {
+	// Set connection args
+	ConfigureConnectionArgs(&ConnectionArgs{
+		MaxIdleConnsPerHost: 1000,
+		MaxIdleConns:        1000,
+	})
+	client1 := getClient()
+
+	require.Same(t, getClient(), client1)
+	require.Equal(t, 1000, castToTransport(client1).MaxIdleConns)
+	require.Equal(t, 1000, castToTransport(client1).MaxIdleConnsPerHost)
+
+	// Set other connection args
+	ConfigureConnectionArgs(&ConnectionArgs{
+		MaxIdleConnsPerHost: 2000,
+		MaxIdleConns:        2000,
+	})
+	client2 := getClient()
+
+	require.Same(t, getClient(), client2)
+	require.Equal(t, 2000, castToTransport(client2).MaxIdleConns)
+	require.Equal(t, 2000, castToTransport(client2).MaxIdleConnsPerHost)
+
+	// Try to set the same value and client should not be cleaned up
+	ConfigureConnectionArgs(&ConnectionArgs{
+		MaxIdleConnsPerHost: 2000,
+		MaxIdleConns:        2000,
+	})
+	require.Same(t, getClient(), client2)
+
+	// Set back to nil
+	ConfigureConnectionArgs(nil)
+	client3 := getClient()
+
+	require.Same(t, getClient(), client3)
+	require.Equal(t, nethttp.DefaultTransport.(*nethttp.Transport).MaxIdleConns, castToTransport(client3).MaxIdleConns)
+	require.Equal(t, nethttp.DefaultTransport.(*nethttp.Transport).MaxIdleConnsPerHost, castToTransport(client3).MaxIdleConnsPerHost)
+
+	require.NotSame(t, client1, client2)
+	require.NotSame(t, client1, client3)
+	require.NotSame(t, client2, client3)
+}
+
+func castToTransport(client *nethttp.Client) *nethttp.Transport {
+	return client.Transport.(*ochttp.Transport).Base.(*nethttp.Transport)
+}

pkg/kncloudevents/message_sender.go

@@ -25,17 +25,10 @@ import (
 
 	"github.com/hashicorp/go-retryablehttp"
 	"github.com/rickb777/date/period"
-	"go.opencensus.io/plugin/ochttp"
-	"knative.dev/pkg/tracing/propagation/tracecontextb3"
 
 	duckv1 "knative.dev/eventing/pkg/apis/duck/v1"
 )
 
-const (
-	defaultRetryWaitMin = 1 * time.Second
-	defaultRetryWaitMax = 30 * time.Second
-)
-
 var noRetries = RetryConfig{
 	RetryMax: 0,
 	CheckRetry: func(ctx context.Context, resp *nethttp.Response, err error) (bool, error) {
@@ -46,41 +39,15 @@ var noRetries = RetryConfig{
 	},
 }
 
-// ConnectionArgs allow to configure connection parameters to the underlying
-// HTTP Client transport.
-type ConnectionArgs struct {
-	// MaxIdleConns refers to the max idle connections, as in net/http/transport.
-	MaxIdleConns int
-	// MaxIdleConnsPerHost refers to the max idle connections per host, as in net/http/transport.
-	MaxIdleConnsPerHost int
-}
-
-func (ca *ConnectionArgs) ConfigureTransport(transport *nethttp.Transport) {
-	if ca == nil {
-		return
-	}
-	transport.MaxIdleConns = ca.MaxIdleConns
-	transport.MaxIdleConnsPerHost = ca.MaxIdleConnsPerHost
-}
-
 type HttpMessageSender struct {
 	Client *nethttp.Client
 	Target string
 }
 
-func NewHttpMessageSender(connectionArgs *ConnectionArgs, target string) (*HttpMessageSender, error) {
-	// Add connection options to the default transport.
-	var base = nethttp.DefaultTransport.(*nethttp.Transport).Clone()
-	connectionArgs.ConfigureTransport(base)
-	// Add output tracing.
-	client := &nethttp.Client{
-		Transport: &ochttp.Transport{
-			Base:        base,
-			Propagation: tracecontextb3.TraceContextEgress,
-		},
-	}
-
-	return &HttpMessageSender{Client: client, Target: target}, nil
+// Deprecated: Don't use this anymore, now it has the same effect of NewHTTPMessageSenderWithTarget
+// If you need to modify the connection args, use ConfigureConnectionArgs sparingly.
+func NewHttpMessageSender(ca *ConnectionArgs, target string) (*HttpMessageSender, error) {
+	return &HttpMessageSender{Client: getClient(), Target: target}, nil
 }
 
 func (s *HttpMessageSender) NewCloudEventRequest(ctx context.Context) (*nethttp.Request, error) {
@@ -184,6 +151,6 @@ func RetryConfigFromDeliverySpec(spec duckv1.DeliverySpec) (RetryConfig, error)
 	return retryConfig, nil
 }
 
-func checkRetry(_ context.Context, resp *nethttp.Response, _ error) (bool, error) {
-	return resp != nil && resp.StatusCode >= 300, nil
+func checkRetry(_ context.Context, resp *nethttp.Response, err error) (bool, error) {
+	return !(resp != nil && resp.StatusCode < 300), err
 }