Add env support to instrumentation kind (#674)

* allow config customized envs on common and language specific node.

* only env name start with "OTEL_" is allowed.

* deployment env > language spec customzied env > language spec config type> common customized env > common config type

* api docs gen and code fmt

* use corev1.EnvVar instead of Env

* fixing wrong change.

* update e2e testcases

* fix unit tests

apis/v1alpha1/instrumentation_types.go

@@ -15,6 +15,7 @@
 package v1alpha1
 
 import (
+	corev1 "k8s.io/api/core/v1"
 	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
 )
 
@@ -36,6 +37,12 @@ type InstrumentationSpec struct {
 	// +optional
 	Sampler `json:"sampler,omitempty"`
 
+	// Env defines common env vars. There are four layers for env vars' definitions and
+	// the precedence order is: `original container env vars` > `language specific env vars` > `common env vars` > `instrument spec configs' vars`.
+	// If the former var had been defined, then the other vars would be ignored.
+	// +optional
+	Env []corev1.EnvVar `json:"env,omitempty"`
+
 	// Java defines configuration for java auto-instrumentation.
 	// +optional
 	Java Java `json:"java,omitempty"`
@@ -88,20 +95,38 @@ type Java struct {
 	// Image is a container image with javaagent auto-instrumentation JAR.
 	// +optional
 	Image string `json:"image,omitempty"`
+
+	// Env defines java specific env vars. There are four layers for env vars' definitions and
+	// the precedence order is: `original container env vars` > `language specific env vars` > `common env vars` > `instrument spec configs' vars`.
+	// If the former var had been defined, then the other vars would be ignored.
+	// +optional
+	Env []corev1.EnvVar `json:"env,omitempty"`
 }
 
 // NodeJS defines NodeJS SDK and instrumentation configuration.
 type NodeJS struct {
 	// Image is a container image with NodeJS SDK and auto-instrumentation.
 	// +optional
 	Image string `json:"image,omitempty"`
+
+	// Env defines nodejs specific env vars. There are four layers for env vars' definitions and
+	// the precedence order is: `original container env vars` > `language specific env vars` > `common env vars` > `instrument spec configs' vars`.
+	// If the former var had been defined, then the other vars would be ignored.
+	// +optional
+	Env []corev1.EnvVar `json:"env,omitempty"`
 }
 
 // Python defines Python SDK and instrumentation configuration.
 type Python struct {
 	// Image is a container image with Python SDK and auto-instrumentation.
 	// +optional
 	Image string `json:"image,omitempty"`
+
+	// Env defines python specific env vars. There are four layers for env vars' definitions and
+	// the precedence order is: `original container env vars` > `language specific env vars` > `common env vars` > `instrument spec configs' vars`.
+	// If the former var had been defined, then the other vars would be ignored.
+	// +optional
+	Env []corev1.EnvVar `json:"env,omitempty"`
 }
 
 // InstrumentationStatus defines status of the instrumentation.

apis/v1alpha1/instrumentation_webhook.go

@@ -17,7 +17,9 @@ package v1alpha1
 import (
 	"fmt"
 	"strconv"
+	"strings"
 
+	corev1 "k8s.io/api/core/v1"
 	"k8s.io/apimachinery/pkg/runtime"
 	ctrl "sigs.k8s.io/controller-runtime"
 	logf "sigs.k8s.io/controller-runtime/pkg/log"
@@ -28,6 +30,7 @@ const (
 	AnnotationDefaultAutoInstrumentationJava   = "instrumentation.opentelemetry.io/default-auto-instrumentation-java-image"
 	AnnotationDefaultAutoInstrumentationNodeJS = "instrumentation.opentelemetry.io/default-auto-instrumentation-nodejs-image"
 	AnnotationDefaultAutoInstrumentationPython = "instrumentation.opentelemetry.io/default-auto-instrumentation-python-image"
+	envPrefix                                  = "OTEL_"
 )
 
 // log is for logging in this package.
@@ -107,5 +110,29 @@ func (in *Instrumentation) validate() error {
 		}
 	case AlwaysOn, AlwaysOff, JaegerRemote, ParentBasedAlwaysOn, ParentBasedAlwaysOff, XRaySampler:
 	}
+
+	// validate env vars
+	if err := in.validateEnv(in.Spec.Env); err != nil {
+		return err
+	}
+	if err := in.validateEnv(in.Spec.Java.Env); err != nil {
+		return err
+	}
+	if err := in.validateEnv(in.Spec.NodeJS.Env); err != nil {
+		return err
+	}
+	if err := in.validateEnv(in.Spec.Python.Env); err != nil {
+		return err
+	}
+
+	return nil
+}
+
+func (in *Instrumentation) validateEnv(envs []corev1.EnvVar) error {
+	for _, env := range envs {
+		if !strings.HasPrefix(env.Name, envPrefix) {
+			return fmt.Errorf("env name should start with \"OTEL_\": %s", env.Name)
+		}
+	}
 	return nil
 }