Add language detection to auto-monitor to inject only the relevant SDK

pkg/instrumentation/auto/language_detector.go

@@ -0,0 +1,211 @@
+// Copyright Amazon.com, Inc. or its affiliates. All Rights Reserved.
+// SPDX-License-Identifier: Apache-2.0
+
+package auto
+
+import (
+	"strings"
+
+	"github.com/go-logr/logr"
+	corev1 "k8s.io/api/core/v1"
+
+	"github.com/aws/amazon-cloudwatch-agent-operator/pkg/instrumentation"
+)
+
+// languageDetector determines the application runtime language from container
+// metadata available in the pod spec: image name, env vars, and command/args.
+type languageDetector struct {
+	logger logr.Logger
+}
+
+func newLanguageDetector(logger logr.Logger) *languageDetector {
+	return &languageDetector{
+		logger: logger,
+	}
+}
+
+// detectLanguages inspects all containers in a pod template and returns the set of
+// detected languages. Returns an empty set if no language can be confidently determined.
+func (d *languageDetector) detectLanguages(podSpec *corev1.PodTemplateSpec) instrumentation.TypeSet {
+	detected := make(instrumentation.TypeSet)
+
+	for _, container := range podSpec.Spec.Containers {
+		if lang := d.detectContainer(container); lang != "" {
+			d.logger.V(2).Info("detected language from container",
+				"container", container.Name, "image", container.Image, "language", lang)
+			detected[lang] = nil
+		}
+	}
+
+	return detected
+}
+
+// detectContainer determines the language from pod-spec metadata only:
+// image name patterns, env vars, and command/args.
+func (d *languageDetector) detectContainer(container corev1.Container) instrumentation.Type {
+	if lang := d.detectFromImageName(container.Image); lang != "" {
+		return lang
+	}
+	if lang := d.detectFromEnvVars(container.Env); lang != "" {
+		return lang
+	}
+	if lang := d.detectFromCommand(container.Command, container.Args); lang != "" {
+		return lang
+	}
+	return ""
+}
+
+// detectFromImageName checks the container image reference string for language indicators.
+func (d *languageDetector) detectFromImageName(image string) instrumentation.Type {
+	lower := strings.ToLower(image)
+
+	javaPatterns := []string{
+		"openjdk", "jdk", "jre", "eclipse-temurin", "amazoncorretto",
+		"corretto", "adoptopenjdk", "ibm-semeru", "graalvm",
+		"tomcat", "jetty", "wildfly", "quarkus", "springboot",
+		"spring-boot", "maven", "gradle", "libertycore", "payara",
+	}
+	for _, p := range javaPatterns {
+		if strings.Contains(lower, p) {
+			return instrumentation.TypeJava
+		}
+	}
+	if strings.Contains(lower, "java") && !strings.Contains(lower, "javascript") {
+		return instrumentation.TypeJava
+	}
+
+	pythonPatterns := []string{
+		"python", "django", "flask", "fastapi", "uvicorn",
+		"gunicorn", "celery", "conda", "miniconda", "anaconda",
+	}
+	for _, p := range pythonPatterns {
+		if strings.Contains(lower, p) {
+			return instrumentation.TypePython
+		}
+	}
+
+	nodePatterns := []string{
+		"node:", "/node:", "nodejs", "node-", "-node",
+		"express", "nextjs", "next.js", "nestjs",
+	}
+	for _, p := range nodePatterns {
+		if strings.Contains(lower, p) {
+			return instrumentation.TypeNodeJS
+		}
+	}
+
+	dotnetPatterns := []string{
+		"dotnet", "aspnet", "asp.net", "mcr.microsoft.com/dotnet",
+	}
+	for _, p := range dotnetPatterns {
+		if strings.Contains(lower, p) {
+			return instrumentation.TypeDotNet
+		}
+	}
+
+	return ""
+}
+
+
+// detectFromEnvVars checks environment variables from the pod spec (corev1.EnvVar format).
+func (d *languageDetector) detectFromEnvVars(envVars []corev1.EnvVar) instrumentation.Type {
+	for _, env := range envVars {
+		envName := strings.ToUpper(env.Name)
+		envValue := strings.ToLower(env.Value)
+
+		if lang := d.classifyEnv(envName, envValue); lang != "" {
+			return lang
+		}
+	}
+	return ""
+}
+
+// classifyEnv determines the language from an env var name and value.
+func (d *languageDetector) classifyEnv(name, value string) instrumentation.Type {
+	switch name {
+	case "JAVA_HOME", "JAVA_TOOL_OPTIONS", "JAVA_OPTS",
+		"JVM_OPTS", "CATALINA_HOME", "CATALINA_OPTS",
+		"MAVEN_HOME", "GRADLE_HOME":
+		return instrumentation.TypeJava
+	}
+
+	switch name {
+	case "PYTHONPATH", "PYTHONHOME", "PYTHONDONTWRITEBYTECODE",
+		"PYTHONUNBUFFERED", "PIP_NO_CACHE_DIR",
+		"PYTHON_VERSION", "PYTHON_SHA256", "PYTHON_PIP_VERSION",
+		"DJANGO_SETTINGS_MODULE", "FLASK_APP":
+		return instrumentation.TypePython
+	}
+
+	switch name {
+	case "NODE_PATH", "NODE_ENV", "NODE_OPTIONS",
+		"NPM_CONFIG_PREFIX", "YARN_CACHE_FOLDER",
+		"NODE_VERSION", "YARN_VERSION":
+		return instrumentation.TypeNodeJS
+	}
+
+	switch name {
+	case "DOTNET_ROOT", "ASPNETCORE_URLS", "ASPNETCORE_ENVIRONMENT",
+		"DOTNET_RUNNING_IN_CONTAINER", "DOTNET_SYSTEM_GLOBALIZATION_INVARIANT",
+		"NUGET_PACKAGES", "CORECLR_ENABLE_PROFILING":
+		return instrumentation.TypeDotNet
+	}
+
+	if name == "PATH" {
+		if strings.Contains(value, "/usr/lib/jvm") || strings.Contains(value, "java") {
+			return instrumentation.TypeJava
+		}
+		if strings.Contains(value, "python") {
+			return instrumentation.TypePython
+		}
+		if strings.Contains(value, "/usr/local/lib/node") || strings.Contains(value, "nodejs") {
+			return instrumentation.TypeNodeJS
+		}
+		if strings.Contains(value, "dotnet") {
+			return instrumentation.TypeDotNet
+		}
+	}
+	return ""
+}
+
+// detectFromCommand checks entrypoint and command args for language indicators.
+func (d *languageDetector) detectFromCommand(command []string, args []string) instrumentation.Type {
+	allParts := append(command, args...)
+	if len(allParts) == 0 {
+		return ""
+	}
+
+	for _, part := range allParts {
+		lower := strings.ToLower(part)
+
+		if lower == "java" || strings.HasSuffix(lower, "/java") ||
+			strings.HasSuffix(lower, ".jar") ||
+			strings.Contains(lower, "-javaagent:") ||
+			strings.Contains(lower, "org.apache.catalina") ||
+			strings.Contains(lower, "org.springframework") {
+			return instrumentation.TypeJava
+		}
+
+		if lower == "python" || lower == "python3" || lower == "python2" ||
+			strings.HasSuffix(lower, "/python") || strings.HasSuffix(lower, "/python3") ||
+			strings.HasSuffix(lower, ".py") ||
+			lower == "gunicorn" || lower == "uvicorn" || lower == "celery" ||
+			lower == "django-admin" || lower == "flask" {
+			return instrumentation.TypePython
+		}
+
+		if lower == "node" || lower == "nodejs" ||
+			strings.HasSuffix(lower, "/node") ||
+			strings.HasSuffix(lower, ".js") || strings.HasSuffix(lower, ".mjs") ||
+			lower == "npm" || lower == "yarn" || lower == "npx" || lower == "pnpm" {
+			return instrumentation.TypeNodeJS
+		}
+
+		if lower == "dotnet" || strings.HasSuffix(lower, "/dotnet") ||
+			strings.HasSuffix(lower, ".dll") {
+			return instrumentation.TypeDotNet
+		}
+	}
+
+	return ""
+}