feat: Add WithResourceOption for additional resource configuration

examples/main.go

@@ -5,12 +5,21 @@ import (
 	"log"
 
 	"go.opentelemetry.io/otel"
+	"go.opentelemetry.io/otel/attribute"
+	"go.opentelemetry.io/otel/sdk/resource"
 
 	"github.com/honeycombio/otel-config-go/otelconfig"
 )
 
 func main() {
-	otelShutdown, err := otelconfig.ConfigureOpenTelemetry()
+	otelShutdown, err := otelconfig.ConfigureOpenTelemetry(
+		otelconfig.WithResourceOption(
+			resource.WithAttributes(
+				attribute.String("resource.example_set_in_code", "CODE"),
+				attribute.String("resource.example_clobber", "CODE_WON"),
+			),
+		),
+	)
 
 	if err != nil {
 		log.Fatalf("error setting up OTel SDK - %e", err)

otelconfig/otelconfig.go

@@ -154,6 +154,14 @@ func WithResourceAttributes(attributes map[string]string) Option {
 	}
 }
 
+// WithResourceOption configures options on the resource; These are appended
+// after the default options and can override them.
+func WithResourceOption(option resource.Option) Option {
+	return func(c *Config) {
+		c.ResourceOptions = append(c.ResourceOptions, option)
+	}
+}
+
 // WithPropagators configures propagators.
 func WithPropagators(propagators []string) Option {
 	return func(c *Config) {
@@ -316,6 +324,7 @@ type Config struct {
 	ResourceAttributes              map[string]string
 	SpanProcessors                  []trace.SpanProcessor
 	Sampler                         trace.Sampler
+	ResourceOptions                 []resource.Option
 	Resource                        *resource.Resource
 	Logger                          Logger                  `json:"-"`
 	ShutdownFunctions               []func(c *Config) error `json:"-"`
@@ -411,13 +420,22 @@ func newResource(c *Config) *resource.Resource {
 
 	attributes = append(r.Attributes(), attributes...)
 
-	// These detectors can't actually fail, ignoring the error.
-	r, _ = resource.New(
-		context.Background(),
+	baseOptions := []resource.Option{
 		resource.WithSchemaURL(semconv.SchemaURL),
 		resource.WithAttributes(attributes...),
+	}
+
+	options := append(baseOptions, c.ResourceOptions...)
+
+	r, err := resource.New(
+		context.Background(),
+		options...,
 	)
 
+	if err != nil {
+		c.Logger.Debugf("error applying resource options: %s", err)
+	}
+
 	// Note: There are new detectors we may wish to take advantage
 	// of, now available in the default SDK (e.g., WithProcess(),
 	// WithOSType(), ...).

otelconfig/otelconfig_test.go

@@ -3,6 +3,7 @@ package otelconfig
 import (
 	"context"
 	"encoding/json"
+	"errors"
 	"fmt"
 	"net"
 	"net/http"
@@ -334,21 +335,23 @@ func TestEnvironmentVariables(t *testing.T) {
 	setEnvironment()
 	logger := &testLogger{}
 	handler := &testErrorHandler{}
-	config := newConfig(
+	testConfig := newConfig(
 		WithLogger(logger),
 		WithErrorHandler(handler),
 	)
 
-	attributes := []attribute.KeyValue{
+	expectedConfiguredResource := resource.NewWithAttributes(
+		semconv.SchemaURL,
 		attribute.String("host.name", host()),
+		attribute.String("resource.clobber", "ENV_WON"),
 		attribute.String("service.name", "test-service-name"),
 		attribute.String("service.version", "test-service-version"),
 		attribute.String("telemetry.sdk.name", "otelconfig"),
 		attribute.String("telemetry.sdk.language", "go"),
 		attribute.String("telemetry.sdk.version", version),
-	}
+	)
 
-	expected := &Config{
+	expectedConfig := &Config{
 		ExporterEndpoint:                "http://generic-url",
 		ExporterEndpointInsecure:        true,
 		TracesExporterEndpoint:          "http://traces-url",
@@ -365,23 +368,32 @@ func TestEnvironmentVariables(t *testing.T) {
 		TracesHeaders:                   map[string]string{},
 		MetricsHeaders:                  map[string]string{},
 		ResourceAttributes:              map[string]string{},
-		ResourceAttributesFromEnv:       "service.name=test-service-name-b",
+		ResourceAttributesFromEnv:       "service.name=test-service-name-b,resource.clobber=ENV_WON",
 		Propagators:                     []string{"b3", "w3c"},
-		Resource:                        resource.NewWithAttributes(semconv.SchemaURL, attributes...),
+		Resource:                        expectedConfiguredResource,
 		Logger:                          logger,
 		ExporterProtocol:                "grpc",
 		errorHandler:                    handler,
 		Sampler:                         trace.AlwaysSample(),
 	}
-	assert.Equal(t, expected, config)
+	assert.Equal(t, expectedConfig, testConfig)
 	unsetEnvironment()
 }
 
+type testDetector struct{}
+
+var _ resource.Detector = (*testDetector)(nil)
+
+// Detect implements resource.Detector.
+func (testDetector) Detect(ctx context.Context) (*resource.Resource, error) {
+	return resource.New(ctx)
+}
+
 func TestConfigurationOverrides(t *testing.T) {
 	setEnvironment()
 	logger := &testLogger{}
 	handler := &testErrorHandler{}
-	config := newConfig(
+	testConfig := newConfig(
 		WithServiceName("override-service-name"),
 		WithServiceVersion("override-service-version"),
 		WithExporterEndpoint("https://override-generic-url"),
@@ -397,18 +409,25 @@ func TestConfigurationOverrides(t *testing.T) {
 		WithExporterProtocol("http/protobuf"),
 		WithMetricsExporterProtocol("http/protobuf"),
 		WithTracesExporterProtocol("http/protobuf"),
+		WithResourceOption(resource.WithAttributes(
+			attribute.String("host.name", "hardcoded-hostname"),
+			attribute.String("resource.clobber", "CODE_WON"),
+		)),
+		WithResourceOption(resource.WithDetectors(&testDetector{})),
 	)
 
-	attributes := []attribute.KeyValue{
-		attribute.String("host.name", host()),
+	expectedConfiguredResource := resource.NewWithAttributes(
+		semconv.SchemaURL,
+		attribute.String("host.name", "hardcoded-hostname"),
+		attribute.String("resource.clobber", "CODE_WON"),
 		attribute.String("service.name", "override-service-name"),
 		attribute.String("service.version", "override-service-version"),
 		attribute.String("telemetry.sdk.name", "otelconfig"),
 		attribute.String("telemetry.sdk.language", "go"),
 		attribute.String("telemetry.sdk.version", version),
-	}
+	)
 
-	expected := &Config{
+	expectedConfig := &Config{
 		ServiceName:                     "override-service-name",
 		ServiceVersion:                  "override-service-version",
 		ExporterEndpoint:                "https://override-generic-url",
@@ -424,17 +443,24 @@ func TestConfigurationOverrides(t *testing.T) {
 		TracesHeaders:                   map[string]string{},
 		MetricsHeaders:                  map[string]string{},
 		ResourceAttributes:              map[string]string{},
-		ResourceAttributesFromEnv:       "service.name=test-service-name-b",
+		ResourceAttributesFromEnv:       "service.name=test-service-name-b,resource.clobber=ENV_WON",
 		Propagators:                     []string{"b3"},
-		Resource:                        resource.NewWithAttributes(semconv.SchemaURL, attributes...),
+		Resource:                        expectedConfiguredResource,
 		Logger:                          logger,
 		ExporterProtocol:                "http/protobuf",
 		TracesExporterProtocol:          "http/protobuf",
 		MetricsExporterProtocol:         "http/protobuf",
 		errorHandler:                    handler,
 		Sampler:                         trace.AlwaysSample(),
+		ResourceOptions: []resource.Option{
+			resource.WithAttributes(
+				attribute.String("host.name", "hardcoded-hostname"),
+				attribute.String("resource.clobber", "CODE_WON"),
+			),
+			resource.WithDetectors(&testDetector{}),
+		},
 	}
-	assert.Equal(t, expected, config)
+	assert.Equal(t, expectedConfig, testConfig)
 	unsetEnvironment()
 }
 
@@ -663,6 +689,41 @@ func TestConfigWithResourceAttributes(t *testing.T) {
 	defer shutdown()
 }
 
+func TestConfigWithResourceAttributesError(t *testing.T) {
+	stopper := dummyGRPCListener()
+	defer stopper()
+
+	logger := &testLogger{}
+	faultyResourceDetector := resource.StringDetector("", "", func() (string, error) {
+		return "", errors.New("faulty resource detector")
+	})
+
+	shutdown, _ := ConfigureOpenTelemetry(
+		WithLogger(logger),
+		WithResourceAttributes(map[string]string{
+			"attr1": "val1",
+			"attr2": "val2",
+		}),
+		WithResourceOption(resource.WithDetectors(faultyResourceDetector)),
+		WithShutdown(func(c *Config) error {
+			attrs := attribute.NewSet(c.Resource.Attributes()...)
+			v, ok := attrs.Value("attr1")
+			assert.Equal(t, "val1", v.AsString())
+			assert.True(t, ok)
+
+			v, ok = attrs.Value("attr2")
+			assert.Equal(t, "val2", v.AsString())
+			assert.True(t, ok)
+
+			logger.requireContains(t, "faulty resource detector")
+
+			return nil
+		}),
+		withTestExporters(),
+	)
+	defer shutdown()
+}
+
 func TestThatEndpointsFallBackCorrectly(t *testing.T) {
 	unsetEnvironment()
 	testCases := []struct {
@@ -918,7 +979,7 @@ func setEnvironment() {
 	setenv("OTEL_METRICS_ENABLED", "false")
 	setenv("OTEL_LOG_LEVEL", "debug")
 	setenv("OTEL_PROPAGATORS", "b3,w3c")
-	setenv("OTEL_RESOURCE_ATTRIBUTES", "service.name=test-service-name-b")
+	setenv("OTEL_RESOURCE_ATTRIBUTES", "service.name=test-service-name-b,resource.clobber=ENV_WON")
 	setenv("OTEL_EXPORTER_OTLP_PROTOCOL", "grpc")
 }
 

smoke-tests/docker-compose.yml

@@ -3,6 +3,7 @@ version: '3.0'
 x-env-base: &env_base
   OTEL_EXPORTER_OTLP_ENDPOINT: http://collector:4317
   OTEL_EXPORTER_OTLP_INSECURE: "true"
+  OTEL_RESOURCE_ATTRIBUTES: resource.example_set_in_env=ENV,resource.example_clobber=ENV_WON
   OTEL_SERVICE_NAME: "my-go-app"
   OTEL_METRICS_ENABLED: "false"
   DEBUG: "true"

smoke-tests/smoke-sdk-grpc.bats

@@ -27,3 +27,18 @@ teardown_file() {
 	result=$(span_names_for ${TRACER_NAME})
 	assert_equal "$result" '"doing-things"'
 }
+
+@test "Resource attributes can be set via environment variable" {
+	env_result=$(spans_received | jq ".resource.attributes[] | select(.key == \"resource.example_set_in_env\") | .value.stringValue")
+	assert_equal "$env_result" '"ENV"'
+}
+
+@test "Resource attributes can be set in code" {
+	code_result=$(spans_received | jq ".resource.attributes[] | select(.key == \"resource.example_set_in_code\") | .value.stringValue")
+	assert_equal "$code_result" '"CODE"'
+}
+
+@test "Resource attributes set in code win over matching key set in environment" {
+	clobber_result=$(spans_received | jq ".resource.attributes[] | select(.key == \"resource.example_clobber\") | .value.stringValue")
+	assert_equal "$clobber_result" '"CODE_WON"'
+}

smoke-tests/smoke-sdk-http.bats

@@ -27,3 +27,18 @@ teardown_file() {
 	result=$(span_names_for ${TRACER_NAME})
 	assert_equal "$result" '"doing-things"'
 }
+
+@test "Resource attributes can be set via environment variable" {
+	env_result=$(spans_received | jq ".resource.attributes[] | select(.key == \"resource.example_set_in_env\") | .value.stringValue")
+	assert_equal "$env_result" '"ENV"'
+}
+
+@test "Resource attributes can be set in code" {
+	code_result=$(spans_received | jq ".resource.attributes[] | select(.key == \"resource.example_set_in_code\") | .value.stringValue")
+	assert_equal "$code_result" '"CODE"'
+}
+
+@test "Resource attributes set in code win over matching key set in environment" {
+	clobber_result=$(spans_received | jq ".resource.attributes[] | select(.key == \"resource.example_clobber\") | .value.stringValue")
+	assert_equal "$clobber_result" '"CODE_WON"'
+}