Add factory and new-style config for Zipkin receiver

This is part of remaining migration to new configuration format.

Github issue: open-telemetry#34

Testing done: make

receiver/zipkinreceiver/config.go

@@ -0,0 +1,22 @@
+// Copyright 2019, OpenCensus 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 zipkinreceiver
+
+import "github.com/open-telemetry/opentelemetry-service/internal/configmodels"
+
+// ConfigV2 defines configuration for Zipkin receiver.
+type ConfigV2 struct {
+	configmodels.ReceiverSettings `mapstructure:",squash"`
+}

receiver/zipkinreceiver/config_test.go

@@ -0,0 +1,54 @@
+// Copyright 2019, OpenCensus 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 zipkinreceiver
+
+import (
+	"path"
+	"testing"
+
+	"github.com/stretchr/testify/assert"
+	"github.com/stretchr/testify/require"
+
+	"github.com/open-telemetry/opentelemetry-service/internal/configmodels"
+	"github.com/open-telemetry/opentelemetry-service/internal/configv2"
+	"github.com/open-telemetry/opentelemetry-service/internal/factories"
+)
+
+var _ = configv2.RegisterTestFactories()
+
+func TestLoadConfig(t *testing.T) {
+	factory := factories.GetReceiverFactory(typeStr)
+
+	config, err := configv2.LoadConfigFile(t, path.Join(".", "testdata", "config.yaml"))
+
+	require.NoError(t, err)
+	require.NotNil(t, config)
+
+	assert.Equal(t, len(config.Receivers), 2)
+
+	r0 := config.Receivers["zipkin"]
+	assert.Equal(t, r0, factory.CreateDefaultConfig())
+
+	r1 := config.Receivers["zipkin/customname"].(*ConfigV2)
+	assert.Equal(t, r1,
+		&ConfigV2{
+			ReceiverSettings: configmodels.ReceiverSettings{
+				TypeVal:  typeStr,
+				NameVal:  "zipkin/customname",
+				Endpoint: "127.0.0.1:8765",
+				Enabled:  true,
+			},
+		})
+}

receiver/zipkinreceiver/factory.go

@@ -0,0 +1,79 @@
+// Copyright 2019, OpenCensus 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 zipkinreceiver
+
+import (
+	"context"
+
+	"github.com/open-telemetry/opentelemetry-service/consumer"
+	"github.com/open-telemetry/opentelemetry-service/internal/configmodels"
+	"github.com/open-telemetry/opentelemetry-service/internal/factories"
+	"github.com/open-telemetry/opentelemetry-service/receiver"
+)
+
+// This file implements config V2 for Zipkin receiver.
+
+var _ = factories.RegisterReceiverFactory(&ReceiverFactory{})
+
+const (
+	// The value of "type" key in configuration.
+	typeStr = "zipkin"
+
+	defaultBindEndpoint = "127.0.0.1:9411"
+)
+
+// ReceiverFactory is the factory for Zipkin receiver.
+type ReceiverFactory struct {
+}
+
+// Type gets the type of the Receiver config created by this factory.
+func (f *ReceiverFactory) Type() string {
+	return typeStr
+}
+
+// CustomUnmarshaler returns nil because we don't need custom unmarshaling for this config.
+func (f *ReceiverFactory) CustomUnmarshaler() factories.CustomUnmarshaler {
+	return nil
+}
+
+// CreateDefaultConfig creates the default configuration for Jaeger receiver.
+func (f *ReceiverFactory) CreateDefaultConfig() configmodels.Receiver {
+	return &ConfigV2{
+		ReceiverSettings: configmodels.ReceiverSettings{
+			TypeVal:  typeStr,
+			NameVal:  typeStr,
+			Endpoint: defaultBindEndpoint,
+		},
+	}
+}
+
+// CreateTraceReceiver creates a trace receiver based on provided config.
+func (f *ReceiverFactory) CreateTraceReceiver(
+	ctx context.Context,
+	cfg configmodels.Receiver,
+	nextConsumer consumer.TraceConsumer,
+) (receiver.TraceReceiver, error) {
+
+	rCfg := cfg.(*ConfigV2)
+	return New(rCfg.Endpoint, nextConsumer)
+}
+
+// CreateMetricsReceiver creates a metrics receiver based on provided config.
+func (f *ReceiverFactory) CreateMetricsReceiver(
+	cfg configmodels.Receiver,
+	consumer consumer.MetricsConsumer,
+) (receiver.MetricsReceiver, error) {
+	return nil, factories.ErrDataTypeIsNotSupported
+}

receiver/zipkinreceiver/factory_test.go

@@ -0,0 +1,49 @@
+// Copyright 2019, OpenCensus 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 zipkinreceiver
+
+import (
+	"context"
+	"testing"
+
+	"github.com/stretchr/testify/assert"
+
+	"github.com/open-telemetry/opentelemetry-service/data"
+	"github.com/open-telemetry/opentelemetry-service/internal/factories"
+)
+
+func TestCreateDefaultConfig(t *testing.T) {
+	factory := factories.GetReceiverFactory(typeStr)
+	cfg := factory.CreateDefaultConfig()
+	assert.NotNil(t, cfg, "failed to create default config")
+}
+
+type mockTraceConsumer struct {
+}
+
+func (m *mockTraceConsumer) ConsumeTraceData(ctx context.Context, td data.TraceData) error { return nil }
+
+func TestCreateReceiver(t *testing.T) {
+	factory := factories.GetReceiverFactory(typeStr)
+	cfg := factory.CreateDefaultConfig()
+
+	tReceiver, err := factory.CreateTraceReceiver(context.Background(), cfg, &mockTraceConsumer{})
+	assert.Nil(t, err, "receiver creation failed")
+	assert.NotNil(t, tReceiver, "receiver creation failed")
+
+	mReceiver, err := factory.CreateMetricsReceiver(cfg, nil)
+	assert.Equal(t, err, factories.ErrDataTypeIsNotSupported)
+	assert.Nil(t, mReceiver)
+}

receiver/zipkinreceiver/testdata/config.yaml

@@ -0,0 +1,18 @@
+receivers:
+  zipkin:
+  zipkin/customname:
+    endpoint: "127.0.0.1:8765"
+    enabled: true
+
+processors:
+  exampleprocessor:
+
+exporters:
+  exampleexporter:
+
+pipelines:
+  traces:
+   receivers: [zipkin]
+   processors: [exampleprocessor]
+   exporters: [exampleexporter]
+