Configuration for tracing in sources

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

pkg/adapter/config.go

@@ -40,6 +40,11 @@ type EnvConfig struct {
 	// This is used to configure the logging config, the config is stored in
 	// a config map inside the controllers namespace and copied here.
 	LoggingConfigJson string `envconfig:"K_LOGGING_CONFIG" required:"true"`
+
+	// TracingConfigJson is a json string of tracing.Config.
+	// This is used to configure the tracing config, the config is stored in
+	// a config map inside the controllers namespace and copied here.
+	TracingConfigJson string `envconfig:"K_TRACING_CONFIG" required:"true"`
 }
 
 // EnvConfigAccessor defines accessors for the minimal
@@ -56,6 +61,9 @@ type EnvConfigAccessor interface {
 
 	// Get the json string of logging.Config.
 	GetLoggingConfigJson() string
+
+	// Get the json string of tracubg.Config.
+	GetTracingConfigJson() string
 }
 
 func (e *EnvConfig) GetMetricsConfigJson() string {
@@ -66,6 +74,10 @@ func (e *EnvConfig) GetLoggingConfigJson() string {
 	return e.LoggingConfigJson
 }
 
+func (e *EnvConfig) GetTracingConfigJson() string {
+	return e.TracingConfigJson
+}
+
 func (e *EnvConfig) GetSinkURI() string {
 	if e.Sink != "" {
 		return e.Sink

pkg/adapter/config_test.go

@@ -33,6 +33,7 @@ func TestEnvConfig(t *testing.T) {
 	os.Setenv("NAMESPACE", "ns")
 	os.Setenv("K_METRICS_CONFIG", "metrics")
 	os.Setenv("K_LOGGING_CONFIG", "logging")
+	os.Setenv("K_TRACING_CONFIG", "tracing")
 	os.Setenv("MODE", "mymode")
 
 	var env myEnvConfig

pkg/adapter/main.go

@@ -36,6 +36,7 @@ import (
 	"knative.dev/pkg/profiling"
 	"knative.dev/pkg/signals"
 	"knative.dev/pkg/source"
+	tracingconfig "knative.dev/pkg/tracing/config"
 
 	"knative.dev/eventing/pkg/kncloudevents"
 	"knative.dev/eventing/pkg/tracing"
@@ -115,7 +116,12 @@ func MainWithContext(ctx context.Context, component string, ector EnvConfigConst
 		logger.Error("error building statsreporter", zap.Error(err))
 	}
 
-	if err = tracing.SetupStaticPublishing(logger, "", tracing.OnePercentSampling); err != nil {
+	// Retrieve tracing config
+	config, err := tracingconfig.JsonToTracingConfig(env.GetTracingConfigJson())
+	if err != nil {
+		logger.Warn("failed to create tracing options, using defaults", zap.Error(err))
+	}
+	if err := tracing.SetupStaticPublishing(logger, component, config); err != nil {
 		// If tracing doesn't work, we will log an error, but allow the adapter
 		// to continue to start.
 		logger.Error("Error setting up trace publishing", zap.Error(err))

pkg/adapter/main_message_adapter.go

@@ -26,6 +26,7 @@ import (
 
 	"knative.dev/pkg/profiling"
 	"knative.dev/pkg/signals"
+	tracingconfig "knative.dev/pkg/tracing/config"
 
 	"github.com/kelseyhightower/envconfig"
 	"go.opencensus.io/stats/view"
@@ -112,7 +113,12 @@ func MainMessageAdapterWithContext(ctx context.Context, component string, ector
 		logger.Error("error building statsreporter", zap.Error(err))
 	}
 
-	if err = tracing.SetupStaticPublishing(logger, "", tracing.OnePercentSampling); err != nil {
+	// Retrieve tracing config
+	config, err := tracingconfig.JsonToTracingConfig(env.GetTracingConfigJson())
+	if err != nil {
+		logger.Warn("failed to create tracing options, using defaults", zap.Error(err))
+	}
+	if err := tracing.SetupStaticPublishing(logger, component, config); err != nil {
 		// If tracing doesn't work, we will log an error, but allow the adapter
 		// to continue to start.
 		logger.Error("Error setting up trace publishing", zap.Error(err))

pkg/adapter/v2/config.go

@@ -19,10 +19,13 @@ import (
 	"encoding/json"
 
 	"go.uber.org/zap"
+	tracingconfig "knative.dev/pkg/tracing/config"
 
 	duckv1 "knative.dev/pkg/apis/duck/v1"
 	"knative.dev/pkg/logging"
 	"knative.dev/pkg/metrics"
+
+	"knative.dev/eventing/pkg/tracing"
 )
 
 type EnvConfigConstructor func() EnvConfigAccessor
@@ -58,6 +61,11 @@ type EnvConfig struct {
 	// This is used to configure the logging config, the config is stored in
 	// a config map inside the controllers namespace and copied here.
 	LoggingConfigJson string `envconfig:"K_LOGGING_CONFIG" required:"true"`
+
+	// TracingConfigJson is a json string of tracing.Config.
+	// This is used to configure the tracing config, the config is stored in
+	// a config map inside the controllers namespace and copied here.
+	TracingConfigJson string `envconfig:"K_TRACING_CONFIG" required:"true"`
 }
 
 // EnvConfigAccessor defines accessors for the minimal
@@ -81,6 +89,9 @@ type EnvConfigAccessor interface {
 	// Get the parsed logger.
 	GetLogger() *zap.SugaredLogger
 
+	// Setup tracing
+	SetupTracing(*zap.SugaredLogger) error
+
 	GetCloudEventOverrides() (*duckv1.CloudEventOverrides, error)
 }
 
@@ -126,6 +137,14 @@ func (e *EnvConfig) GetName() string {
 	return e.Name
 }
 
+func (e *EnvConfig) SetupTracing(logger *zap.SugaredLogger) error {
+	config, err := tracingconfig.JsonToTracingConfig(e.TracingConfigJson)
+	if err != nil {
+		logger.Error("Tracing configuration is invalid, using the no-op default", zap.Error(err))
+	}
+	return tracing.SetupStaticPublishing(logger, e.Component, config)
+}
+
 func (e *EnvConfig) GetCloudEventOverrides() (*duckv1.CloudEventOverrides, error) {
 	var ceOverrides duckv1.CloudEventOverrides
 	if len(e.CEOverrides) > 0 {

pkg/adapter/v2/config_test.go

@@ -33,6 +33,7 @@ func TestEnvConfig(t *testing.T) {
 	os.Setenv("NAMESPACE", "ns")
 	os.Setenv("K_METRICS_CONFIG", "metrics")
 	os.Setenv("K_LOGGING_CONFIG", "logging")
+	os.Setenv("K_TRACING_CONFIG", "tracing")
 	os.Setenv("MODE", "mymode") // note: custom to this test impl
 
 	var env myEnvConfig

pkg/adapter/v2/main.go

@@ -24,7 +24,6 @@ import (
 	"time"
 
 	cloudevents "github.com/cloudevents/sdk-go/v2"
-
 	"github.com/kelseyhightower/envconfig"
 	"go.opencensus.io/stats/view"
 	"go.uber.org/zap"
@@ -33,8 +32,6 @@ import (
 	"knative.dev/pkg/profiling"
 	"knative.dev/pkg/signals"
 	"knative.dev/pkg/source"
-
-	"knative.dev/eventing/pkg/tracing"
 )
 
 type Adapter interface {
@@ -95,7 +92,8 @@ func MainWithContext(ctx context.Context, component string, ector EnvConfigConst
 		logger.Error("error building statsreporter", zap.Error(err))
 	}
 
-	if err = tracing.SetupStaticPublishing(logger, "", tracing.OnePercentSampling); err != nil {
+	// Setup tracing
+	if err := env.SetupTracing(logger); err != nil {
 		// If tracing doesn't work, we will log an error, but allow the adapter
 		// to continue to start.
 		logger.Error("Error setting up trace publishing", zap.Error(err))

vendor/knative.dev/pkg/tracing/config/tracing.go

@@ -17,6 +17,7 @@ limitations under the License.
 package config
 
 import (
+	"encoding/json"
 	"errors"
 	"fmt"
 	"reflect"
@@ -139,3 +140,43 @@ func NewTracingConfigFromMap(cfgMap map[string]string) (*Config, error) {
 func NewTracingConfigFromConfigMap(config *corev1.ConfigMap) (*Config, error) {
 	return NewTracingConfigFromMap(config.Data)
 }
+
+// JsonToTracingConfig converts a json string of a Config.
+// Returns a non-nil Config always and an eventual error.
+func JsonToTracingConfig(jsonCfg string) (*Config, error) {
+	if jsonCfg == "" {
+		return defaultConfig(), errors.New("empty json tracing config")
+	}
+
+	var configMap map[string]string
+	if err := json.Unmarshal([]byte(jsonCfg), &configMap); err != nil {
+		return defaultConfig(), err
+	}
+
+	cfg, err := NewTracingConfigFromMap(configMap)
+	if err != nil {
+		return defaultConfig(), nil
+	}
+	return cfg, nil
+}
+
+// TracingConfigToJson converts a Config to a json string.
+func TracingConfigToJson(cfg *Config) (string, error) {
+	if cfg == nil {
+		return "", nil
+	}
+
+	out := make(map[string]string, 5)
+	out[backendKey] = string(cfg.Backend)
+	if cfg.ZipkinEndpoint != "" {
+		out[zipkinEndpointKey] = cfg.ZipkinEndpoint
+	}
+	if cfg.StackdriverProjectID != "" {
+		out[stackdriverProjectIDKey] = cfg.StackdriverProjectID
+	}
+	out[debugKey] = strconv.FormatBool(cfg.Debug)
+	out[sampleRateKey] = strconv.FormatFloat(cfg.SampleRate, 'f', -1, 64)
+
+	jsonCfg, err := json.Marshal(out)
+	return string(jsonCfg), err
+}