Add Amazon ECS Resource Detector

.github/dependabot.yml

@@ -37,6 +37,16 @@ updates:
     schedule:
       interval: "weekly"
       day: "sunday"
+  -
+    package-ecosystem: "gomod"
+    directory: "/detectors/aws/ecs"
+    labels:
+      - dependencies
+      - go
+      - "Skip Changelog"
+    schedule:
+      interval: "weekly"
+      day: "sunday"
   -
     package-ecosystem: "gomod"
     directory: "/detectors/gcp"

CHANGELOG.md

@@ -14,6 +14,7 @@ This project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0.htm
 
 - `otelhttp.{Get,Head,Post,PostForm}` convenience wrappers for their `http` counterparts. (#390)
 - The AWS detector now adds the cloud zone, host image ID, host type, and host name to the returned `Resource`. (#410)
+- Add Amazon ECS Resource Detector for AWS X-Ray. (#466)
 
 ### Changed
 

detectors/aws/ecs/ecs.go

@@ -0,0 +1,106 @@
+// 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://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 ecs
+
+import (
+	"context"
+	"errors"
+	"io/ioutil"
+	"os"
+	"strings"
+
+	"go.opentelemetry.io/otel/label"
+	"go.opentelemetry.io/otel/sdk/resource"
+	"go.opentelemetry.io/otel/semconv"
+)
+
+const (
+	TypeStr           = "ecs"
+	metadataV3EnvVar  = "ECS_CONTAINER_METADATA_URI"
+	metadataV4EnvVar  = "ECS_CONTAINER_METADATA_URI_V4"
+	containerIDLength = 64
+	defaultCgroupPath = "/proc/self/cgroup"
+)
+
+var (
+	empty                    = resource.Empty()
+	errCannotReadContainerID = errors.New("failed to read container ID from cGroupFile")
+	errCannotReadCGroupFile  = errors.New("ECS resource detector failed to read cGroupFile")
+	errNotOnECS              = errors.New("process is not on ECS, cannot detect environment variables from ECS")
+)
+
+// Create interface for methods needing to be mocked
+type detectorUtils interface {
+	getContainerName() (string, error)
+	getContainerID() (string, error)
+}
+
+// struct implements detectorUtils interface
+type ecsDetectorUtils struct{}
+
+// resource detector collects resource information from Elastic Container Service environment
+type ResourceDetector struct {
+	utils detectorUtils
+}
+
+// compile time assertion that ecsDetectorUtils implements detectorUtils interface
+var _ detectorUtils = (*ecsDetectorUtils)(nil)
+
+// compile time assertion that resource detector implements the resource.Detector interface.
+var _ resource.Detector = (*ResourceDetector)(nil)
+
+// Detect finds associated resources when running on ECS environment.
+func (detector *ResourceDetector) Detect(ctx context.Context) (*resource.Resource, error) {
+	metadataURIV3 := os.Getenv(metadataV3EnvVar)
+	metadataURIV4 := os.Getenv(metadataV4EnvVar)
+
+	if len(metadataURIV3) == 0 && len(metadataURIV4) == 0 {
+		return empty, errNotOnECS
+	}
+	hostName, err := detector.utils.getContainerName()
+	if err != nil {
+		return empty, err
+	}
+	containerID, err := detector.utils.getContainerID()
+	if err != nil {
+		return empty, err
+	}
+	labels := []label.KeyValue{
+		semconv.ContainerNameKey.String(hostName),
+		semconv.ContainerIDKey.String(containerID),
+	}
+
+	return resource.NewWithAttributes(labels...), nil
+}
+
+// returns docker container ID from default c group path
+func (ecsUtils ecsDetectorUtils) getContainerID() (string, error) {
+	fileData, err := ioutil.ReadFile(defaultCgroupPath)
+	if err != nil {
+		return "", errCannotReadCGroupFile
+	}
+	splitData := strings.Split(strings.TrimSpace(string(fileData)), "\n")
+	for _, str := range splitData {
+		if len(str) > containerIDLength {
+			return str[len(str)-containerIDLength:], nil
+		}
+	}
+	return "", errCannotReadContainerID
+}
+
+// returns host name reported by the kernel
+func (ecsUtils ecsDetectorUtils) getContainerName() (string, error) {
+	return os.Hostname()
+}

detectors/aws/ecs/ecs_test.go

@@ -0,0 +1,92 @@
+// 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://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 ecs
+
+import (
+	"context"
+	"os"
+	"testing"
+
+	"github.com/bmizerany/assert"
+	"github.com/stretchr/testify/mock"
+
+	"go.opentelemetry.io/otel/label"
+	"go.opentelemetry.io/otel/sdk/resource"
+	"go.opentelemetry.io/otel/semconv"
+)
+
+// Create interface for functions that need to be mocked
+type MockDetectorUtils struct {
+	mock.Mock
+}
+
+func (detectorUtils *MockDetectorUtils) getContainerID() (string, error) {
+	args := detectorUtils.Called()
+	return args.String(0), args.Error(1)
+}
+
+func (detectorUtils *MockDetectorUtils) getContainerName() (string, error) {
+	args := detectorUtils.Called()
+	return args.String(0), args.Error(1)
+}
+
+//succesfully return resource when process is running on Amazon ECS environment
+func TestDetect(t *testing.T) {
+	os.Clearenv()
+	os.Setenv(metadataV3EnvVar, "3")
+	os.Setenv(metadataV4EnvVar, "4")
+
+	detectorUtils := new(MockDetectorUtils)
+
+	detectorUtils.On("getContainerName").Return("container-Name", nil)
+	detectorUtils.On("getContainerID").Return("0123456789A", nil)
+
+	labels := []label.KeyValue{
+		semconv.ContainerNameKey.String("container-Name"),
+		semconv.ContainerIDKey.String("0123456789A"),
+	}
+	expectedResource := resource.NewWithAttributes(labels...)
+	detector := ResourceDetector{detectorUtils}
+	resource, _ := detector.Detect(context.Background())
+
+	assert.Equal(t, resource, expectedResource, "Resource returned is incorrect")
+}
+
+//returns empty resource when detector cannot read container ID
+func TestDetectCannotReadContainerID(t *testing.T) {
+	os.Clearenv()
+	os.Setenv(metadataV3EnvVar, "3")
+	os.Setenv(metadataV4EnvVar, "4")
+	detectorUtils := new(MockDetectorUtils)
+
+	detectorUtils.On("getContainerName").Return("container-Name", nil)
+	detectorUtils.On("getContainerID").Return("", errCannotReadContainerID)
+
+	detector := ResourceDetector{detectorUtils}
+	resource, err := detector.Detect(context.Background())
+
+	assert.Equal(t, errCannotReadContainerID, err)
+	assert.Equal(t, 0, len(resource.Attributes()))
+}
+
+//returns empty resource when process is not running ECS
+func TestReturnsIfNoEnvVars(t *testing.T) {
+	os.Clearenv()
+	detector := ResourceDetector{}
+	resource, err := detector.Detect(context.Background())
+
+	assert.Equal(t, errNotOnECS, err)
+	assert.Equal(t, 0, len(resource.Attributes()))
+}

detectors/aws/ecs/go.mod

@@ -0,0 +1,11 @@
+module github.com/kkelvinlo/opentelemetry-go-contrib/detectors/aws/ecs
+
+go 1.15
+
+require (
+	github.com/bmizerany/assert v0.0.0-20160611221934-b7ed37b82869
+	github.com/kr/pretty v0.2.1 // indirect
+	github.com/stretchr/testify v1.6.1
+	go.opentelemetry.io/otel v0.14.0
+	go.opentelemetry.io/otel/sdk v0.14.0
+)

detectors/aws/ecs/go.sum

@@ -0,0 +1,30 @@
+github.com/DataDog/sketches-go v0.0.1/go.mod h1:Q5DbzQ+3AkgGwymQO7aZFNP7ns2lZKGtvRBzRXfdi60=
+github.com/benbjohnson/clock v1.0.3/go.mod h1:bGMdMPoPVvcYyt1gHDf4J2KE153Yf9BuiUKYMaxlTDM=
+github.com/bmizerany/assert v0.0.0-20160611221934-b7ed37b82869 h1:DDGfHa7BWjL4YnC6+E63dPcxHo2sUxDIu8g3QgEJdRY=
+github.com/bmizerany/assert v0.0.0-20160611221934-b7ed37b82869/go.mod h1:Ekp36dRnpXw/yCqJaO+ZrUyxD+3VXMFFr56k5XYrpB4=
+github.com/davecgh/go-spew v1.1.0 h1:ZDRjVQ15GmhC3fiQ8ni8+OwkZQO4DARzQgrnXU1Liz8=
+github.com/davecgh/go-spew v1.1.0/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
+github.com/google/go-cmp v0.5.3 h1:x95R7cp+rSeeqAMI2knLtQ0DKlaBhv2NrtrOvafPHRo=
+github.com/google/go-cmp v0.5.3/go.mod h1:v8dTdLbMG2kIc/vJvl+f65V22dbkXbowE6jgT/gNBxE=
+github.com/google/gofuzz v1.1.0/go.mod h1:dBl0BpW6vV/+mYPU4Po3pmUjxk6FQPldtuIdl/M65Eg=
+github.com/kr/pretty v0.2.1 h1:Fmg33tUaq4/8ym9TJN1x7sLJnHVwhP33CNkpYV/7rwI=
+github.com/kr/pretty v0.2.1/go.mod h1:ipq/a2n7PKx3OHsz4KJII5eveXtPO4qwEXGdVfWzfnI=
+github.com/kr/pty v1.1.1/go.mod h1:pFQYn66WHrOpPYNljwOMqo10TkYh1fy3cYio2l3bCsQ=
+github.com/kr/text v0.1.0 h1:45sCR5RtlFHMR4UwH9sdQ5TC8v0qDQCHnXt+kaKSTVE=
+github.com/kr/text v0.1.0/go.mod h1:4Jbv+DJW3UT/LiOwJeYQe1efqtUx/iVham/4vfdArNI=
+github.com/pmezard/go-difflib v1.0.0 h1:4DBwDE0NGyQoBHbLQYPwSUPoCMWR5BEzIk/f1lZbAQM=
+github.com/pmezard/go-difflib v1.0.0/go.mod h1:iKH77koFhYxTK1pcRnkKkqfTogsbg7gZNVY4sRDYZ/4=
+github.com/stretchr/objx v0.1.0 h1:4G4v2dO3VZwixGIRoQ5Lfboy6nUhCyYzaqnIAPPhYs4=
+github.com/stretchr/objx v0.1.0/go.mod h1:HFkY916IF+rwdDfMAkV7OtwuqBVzrE8GR6GFx+wExME=
+github.com/stretchr/testify v1.6.1 h1:hDPOHmpOpP40lSULcqw7IrRb/u7w6RpDC9399XyoNd0=
+github.com/stretchr/testify v1.6.1/go.mod h1:6Fq8oRcR53rry900zMqJjRRixrwX3KX962/h/Wwjteg=
+go.opentelemetry.io/otel v0.14.0 h1:YFBEfjCk9MTjaytCNSUkp9Q8lF7QJezA06T71FbQxLQ=
+go.opentelemetry.io/otel v0.14.0/go.mod h1:vH5xEuwy7Rts0GNtsCW3HYQoZDY+OmBJ6t1bFGGlxgw=
+go.opentelemetry.io/otel/sdk v0.14.0 h1:Pqgd85y5XhyvHQlOxkKW+FD4DAX7AoeaNIDKC2VhfHQ=
+go.opentelemetry.io/otel/sdk v0.14.0/go.mod h1:kGO5pEMSNqSJppHAm8b73zztLxB5fgDQnD56/dl5xqE=
+golang.org/x/xerrors v0.0.0-20191204190536-9bdfabe68543 h1:E7g+9GITq07hpfrRu66IVDexMakfv52eLZ2CXBWiKr4=
+golang.org/x/xerrors v0.0.0-20191204190536-9bdfabe68543/go.mod h1:I/5z698sn9Ka8TeJc9MKroUUfqBBauWjQqLJ2OPfmY0=
+gopkg.in/check.v1 v0.0.0-20161208181325-20d25e280405 h1:yhCVgyC4o1eVCa2tZl7eS0r+SDo693bJlVdllGtEeKM=
+gopkg.in/check.v1 v0.0.0-20161208181325-20d25e280405/go.mod h1:Co6ibVJAznAaIkqp8huTwlJQCZ016jof/cbN4VW5Yz0=
+gopkg.in/yaml.v3 v3.0.0-20200313102051-9f266ea9e77c h1:dUUwHk2QECo/6vqA44rthZ8ie2QXMNeKRTHCNY2nXvo=
+gopkg.in/yaml.v3 v3.0.0-20200313102051-9f266ea9e77c/go.mod h1:K4uyk7z7BCEPqu6E+C64Yfv1cQ7kz7rIZviUmN+EgEM=