Add Google Pubsub receiver for OTLP messages

go.mod

@@ -215,6 +215,8 @@ replace github.com/open-telemetry/opentelemetry-collector-contrib/receiver/memca
 
 replace github.com/open-telemetry/opentelemetry-collector-contrib/receiver/kafkametricsreceiver => ./receiver/kafkametricsreceiver
 
+replace github.com/open-telemetry/opentelemetry-collector-contrib/receiver/googlecloudpubsubreceiver => ./receiver/googlecloudpubsubreceiver
+
 replace github.com/open-telemetry/opentelemetry-collector-contrib/processor/groupbyattrsprocessor => ./processor/groupbyattrsprocessor
 
 replace github.com/open-telemetry/opentelemetry-collector-contrib/processor/groupbytraceprocessor => ./processor/groupbytraceprocessor

receiver/googlecloudpubsubreceiver/Makefile

@@ -0,0 +1 @@
+include ../../Makefile.Common

receiver/googlecloudpubsubreceiver/README.md

@@ -0,0 +1,61 @@
+# Google Pubsub Receiver
+
+This receiver gets OTLP messages from a Google Cloud [Pubsub](https://cloud.google.com/pubsub) subscription.
+
+The following configuration options are supported:
+
+* `project` (Required): The Google Cloud Project of the client connects to.
+* `subscription` (Required): The subscription name to receive OTLP data from. The subscription name should be a 
+ fully qualified resource name (eg: `projects/otel-project/subscriptions/otlp`).
+* `encoding` (Options): The encoding that will be used to received data from the subscription. This can either be
+ `otlp_proto_trace`, `otlp_proto_metric`, `otlp_proto_log`, or `raw_text` (see `encoding`)
+
+```yaml
+receivers:
+ googlecloudpubsub:
+ project: otel-project
+ subscription: projects/otel-project/subscriptions/otlp-logs
+ encoding: raw_json
+```
+
+## Encoding
+
+You should not need to set the encoding of the subscription as the receiver will try to discover the type of the data
+by looking at the `ce-type` as `ce-datacontenttype` attributes of the message. Only when those attributes are not set 
+the `encoding` field in the configuration should be set. 
+
+| ce-type] | ce-datacontenttype | encoding | description |
+| --- | --- | --- | --- |
+| org.opentelemetry.otlp.traces.v1 | application/x-protobuf | | Decode OTLP trace message |
+| org.opentelemetry.otlp.metrics.v1 | application/x-protobuf | | Decode OTLP metric message |
+| org.opentelemetry.otlp.logs.v1 | application/json | | Decode OTLP log message |
+| - | - | otlp_proto_trace | Decode OTLP trace message |
+| - | - | otlp_proto_metric | Decode OTLP trace message |
+| - | - | otlp_proto_log | Decode OTLP trace message |
+| - | - | raw_text | Wrap in an OTLP log message |
+
+When the `encoding` configuration is set, the attributes on the message are ignored.
+
+The receiver can be used for ingesting arbitrary text message on a Pubsub subscription and wrap them in OTLP Log
+message, making it a convenient way to ingest log lines from Pubsub.
+
+## Pubsub subscription
+
+The Google Cloud [Pubsub](https://cloud.google.com/pubsub) receiver doesn't automatic create subscriptions, 
+it expects the subscription to be created upfront. Security wise it's best to give the collector its own 
+service account and give the subscription `Pub/Sub Subscriber` permission.
+
+The subscription should also be of delivery type `Pull`.
+
+### Filtering
+
+When the messages on the subscription are accompanied by the correct attributes and you only need a specific
+type in your pipeline, the messages can be [filtered](https://cloud.google.com/pubsub/docs/filtering) on the 
+subscription saving on egress fees.
+
+An example of filtering on trace message only: 
+```
+attributes.ce-type = "org.opentelemetry.otlp.traces.v1"
+AND
+attributes.ce-datacontenttype = "application/x-protobuf"
+```

receiver/googlecloudpubsubreceiver/config.go

@@ -0,0 +1,99 @@
+// Copyright The OpenTelemetry 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:https://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 googlecloudpubsubreceiver
+
+import (
+ "fmt"
+ "regexp"
+
+ "go.opentelemetry.io/collector/config"
+ "go.opentelemetry.io/collector/exporter/exporterhelper"
+)
+
+var subscriptionMatcher = regexp.MustCompile(`projects/[a-z][a-z0-9\-]*/subscriptions/.*`)
+
+type Config struct {
+ config.ReceiverSettings `mapstructure:",squash"`
+
+ // Google Cloud Project ID where the Pubsub client will connect to
+ ProjectID string `mapstructure:"project"`
+ // User agent that will be used by the Pubsub client to connect to the service
+ UserAgent string `mapstructure:"user_agent"`
+ // Override of the Pubsub endpoint
+ Endpoint string `mapstructure:"endpoint"`
+ // Only has effect if Endpoint is not ""
+ UseInsecure bool `mapstructure:"use_insecure"`
+ // Timeout for all API calls. If not set, defaults to 12 seconds.
+ exporterhelper.TimeoutSettings `mapstructure:",squash"` // squash ensures fields are correctly decoded in embedded struct.
+
+ // The fully qualified resource name of the Pubsub subscription
+ Subscription string `mapstructure:"subscription"`
+ // Lock down the encoding of the payload, leave empty for attribute based detection
+ Encoding string `mapstructure:"encoding"`
+
+ // The client id that will be used by Pubsub to make load balancing decisions
+ ClientID string `mapstructure:"client_id"`
+}
+
+func (config *Config) validateForLog() error {
+ err := config.validate()
+ if err != nil {
+ return err
+ }
+ switch config.Encoding {
+ case "":
+ case "otlp_proto_log":
+ case "raw_text":
+ case "raw_json":
+ default:
+ return fmt.Errorf("if specified, log encoding should be either otlp_proto_log, raw_text or raw_json")
+ }
+ return nil
+}
+
+func (config *Config) validateForTrace() error {
+ err := config.validate()
+ if err != nil {
+ return err
+ }
+ switch config.Encoding {
+ case "":
+ case "otlp_proto_trace":
+ default:
+ return fmt.Errorf("log format should be either otlp_proto, raw_string or raw_json")
+ }
+ return nil
+}
+
+func (config *Config) validateForMetric() error {
+ err := config.validate()
+ if err != nil {
+ return err
+ }
+ switch config.Encoding {
+ case "":
+ case "otlp_proto_metric":
+ default:
+ return fmt.Errorf("log format should be either otlp_proto, raw_string or raw_json")
+ }
+ return nil
+}
+
+func (config *Config) validate() error {
+ if !subscriptionMatcher.MatchString(config.Subscription) {
+ return fmt.Errorf("subscription '%s' is not a valide format, use 'projects/<project_id>/subscriptions/<name>'", config.Subscription)
+ }
+ return nil
+}

receiver/googlecloudpubsubreceiver/config_test.go

@@ -0,0 +1,131 @@
+// Copyright The OpenTelemetry 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:https://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 googlecloudpubsubreceiver
+
+import (
+ "path"
+ "testing"
+ "time"
+
+ "github.com/stretchr/testify/assert"
+ "github.com/stretchr/testify/require"
+ "go.opentelemetry.io/collector/component/componenttest"
+ "go.opentelemetry.io/collector/config"
+ "go.opentelemetry.io/collector/config/configtest"
+ "go.opentelemetry.io/collector/exporter/exporterhelper"
+)
+
+func TestLoadConfig(t *testing.T) {
+ factories, err := componenttest.NopFactories()
+ assert.Nil(t, err)
+
+ factory := NewFactory()
+ factories.Receivers[config.Type(typeStr)] = factory
+ cfg, err := configtest.LoadConfigFile(
+ t, path.Join(".", "testdata", "config.yaml"), factories,
+ )
+
+ require.NoError(t, err)
+ require.NotNil(t, cfg)
+
+ assert.Equal(t, len(cfg.Receivers), 2)
+
+ defaultConfig := factory.CreateDefaultConfig().(*Config)
+ assert.Equal(t, cfg.Receivers[config.NewID(typeStr)], defaultConfig)
+
+ customConfig := factory.CreateDefaultConfig().(*Config)
+ customConfig.SetIDName("customname")
+
+ customConfig.ProjectID = "my-project"
+ customConfig.UserAgent = "opentelemetry-collector-contrib {{version}}"
+ customConfig.Endpoint = "test-endpoint"
+ customConfig.UseInsecure = true
+ customConfig.TimeoutSettings = exporterhelper.TimeoutSettings{
+ Timeout: 20 * time.Second,
+ }
+ customConfig.Subscription = "projects/my-project/subscriptions/otlp-subscription"
+ assert.Equal(t, cfg.Receivers[config.NewIDWithName(typeStr, "customname")], customConfig)
+}
+
+func TestConfigValidation(t *testing.T) {
+ factory := NewFactory()
+ config := factory.CreateDefaultConfig().(*Config)
+ assert.Error(t, config.validateForTrace())
+ assert.Error(t, config.validateForLog())
+ assert.Error(t, config.validateForMetric())
+ config.Subscription = "projects/000project/subscriptions/my-subscription"
+ assert.Error(t, config.validate())
+ config.Subscription = "projects/my-project/topics/my-topic"
+ assert.Error(t, config.validate())
+ config.Subscription = "projects/my-project/subscriptions/my-subscription"
+ assert.NoError(t, config.validate())
+}
+
+func TestTraceConfigValidation(t *testing.T) {
+ factory := NewFactory()
+ config := factory.CreateDefaultConfig().(*Config)
+ config.Subscription = "projects/my-project/subscriptions/my-subscription"
+ assert.NoError(t, config.validateForTrace())
+
+ config.Encoding = "otlp_proto_metric"
+ assert.Error(t, config.validateForTrace())
+ config.Encoding = "otlp_proto_log"
+ assert.Error(t, config.validateForTrace())
+ config.Encoding = "raw_text"
+ assert.Error(t, config.validateForTrace())
+ config.Encoding = "raw_json"
+ assert.Error(t, config.validateForTrace())
+
+ config.Encoding = "otlp_proto_trace"
+ assert.NoError(t, config.validateForTrace())
+}
+
+func TestMetricConfigValidation(t *testing.T) {
+ factory := NewFactory()
+ config := factory.CreateDefaultConfig().(*Config)
+ config.Subscription = "projects/my-project/subscriptions/my-subscription"
+ assert.NoError(t, config.validateForMetric())
+
+ config.Encoding = "otlp_proto_trace"
+ assert.Error(t, config.validateForMetric())
+ config.Encoding = "otlp_proto_log"
+ assert.Error(t, config.validateForMetric())
+ config.Encoding = "raw_text"
+ assert.Error(t, config.validateForMetric())
+ config.Encoding = "raw_json"
+ assert.Error(t, config.validateForMetric())
+
+ config.Encoding = "otlp_proto_metric"
+ assert.NoError(t, config.validateForMetric())
+}
+
+func TestLogConfigValidation(t *testing.T) {
+ factory := NewFactory()
+ config := factory.CreateDefaultConfig().(*Config)
+ config.Subscription = "projects/my-project/subscriptions/my-subscription"
+ assert.NoError(t, config.validateForLog())
+
+ config.Encoding = "otlp_proto_trace"
+ assert.Error(t, config.validateForLog())
+ config.Encoding = "otlp_proto_metric"
+ assert.Error(t, config.validateForLog())
+
+ config.Encoding = "raw_text"
+ assert.NoError(t, config.validateForLog())
+ config.Encoding = "raw_json"
+ assert.NoError(t, config.validateForLog())
+ config.Encoding = "otlp_proto_log"
+ assert.NoError(t, config.validateForLog())
+}