feat: add musl build to python autoinstrumentation

Author: ilyamochalov

README.md

@@ -250,8 +250,13 @@ instrumentation.opentelemetry.io/inject-nodejs: "true"
 ```
 
 Python:
+Python auto-instrumentation also honors an annotation that will be used to set Python runtime C library implementation.
+Currently, two C library implementations are supported: `linux-x64` and `linux-musl-x64`.
+By default `linux-x64` is used.
 ```bash
-instrumentation.opentelemetry.io/inject-python: "true"
+instrumentation.opentelemetry.io/inject-: "true"
+instrumentation.opentelemetry.io/otel-python-auto-runtime: "linux-x64" # for Linux glibc based images, this is default value and can be omitted
+instrumentation.opentelemetry.io/otel-python-auto-runtime: "linux-musl-x64"  # for Linux musl based images
 ```
 
 .NET:

autoinstrumentation/python/Dockerfile

@@ -9,6 +9,7 @@
 # - Grant the necessary access to `/autoinstrumentation` directory. `chmod -R go+r /autoinstrumentation`
 # - For auto-instrumentation by container injection, the Linux command cp is
 #   used and must be availabe in the image.
+# - Please note that we build twice. First time for environments with libc and second time with musl C implementations
 FROM python:3.11 AS build
 
 WORKDIR /operator-build
@@ -17,8 +18,18 @@ ADD requirements.txt .
 
 RUN mkdir workspace && pip install --target workspace -r requirements.txt
 
+FROM python:3.11-alpine AS build-musl
+
+WORKDIR /operator-build
+
+ADD requirements.txt .
+
+RUN apk add --update --no-cache gcc musl-dev linux-headers
+RUN mkdir workspace && pip install --target workspace -r requirements.txt
+
 FROM busybox
 
-COPY --from=build /operator-build/workspace /autoinstrumentation
+COPY --from=build /operator-build/workspace /autoinstrumentation/linux-x64
+COPY --from=build-musl /operator-build/workspace /autoinstrumentation/linux-musl-x64
 
 RUN chmod -R go+r /autoinstrumentation

pkg/instrumentation/annotation.go

@@ -29,6 +29,7 @@ const (
 	annotationInjectNodeJS                    = "instrumentation.opentelemetry.io/inject-nodejs"
 	annotationInjectNodeJSContainersName      = "instrumentation.opentelemetry.io/nodejs-container-names"
 	annotationInjectPython                    = "instrumentation.opentelemetry.io/inject-python"
+	annotationPythonRuntime                   = "instrumentation.opentelemetry.io/otel-python-auto-runtime"
 	annotationInjectPythonContainersName      = "instrumentation.opentelemetry.io/python-container-names"
 	annotationInjectDotNet                    = "instrumentation.opentelemetry.io/inject-dotnet"
 	annotationDotNetRuntime                   = "instrumentation.opentelemetry.io/otel-dotnet-auto-runtime"

pkg/instrumentation/podmutator.go

@@ -252,6 +252,7 @@ func (pm *instPodMutator) Mutate(ctx context.Context, ns corev1.Namespace, pod c
 	}
 	if featuregate.EnablePythonAutoInstrumentationSupport.IsEnabled() || inst == nil {
 		insts.Python.Instrumentation = inst
+		insts.Python.AdditionalAnnotations = map[string]string{annotationPythonRuntime: annotationValue(ns.ObjectMeta, pod.ObjectMeta, annotationPythonRuntime)}
 	} else {
 		logger.Error(nil, "support for Python auto instrumentation is not enabled")
 		pm.Recorder.Event(pod.DeepCopy(), "Warning", "InstrumentationRequestRejected", "support for Python auto instrumentation is not enabled")

pkg/instrumentation/podmutator_test.go

@@ -1205,7 +1205,7 @@ func TestMutatePod(t *testing.T) {
 								},
 								{
 									Name:  "PYTHONPATH",
-									Value: fmt.Sprintf("%s:%s", pythonPathPrefix, pythonPathSuffix),
+									Value: fmt.Sprintf("%s:%s", pythonPathGlibcPrefix, pythonPathGlibcSuffix),
 								},
 								{
 									Name:  "OTEL_EXPORTER_OTLP_TRACES_PROTOCOL",
@@ -1393,7 +1393,7 @@ func TestMutatePod(t *testing.T) {
 								},
 								{
 									Name:  "PYTHONPATH",
-									Value: fmt.Sprintf("%s:%s", pythonPathPrefix, pythonPathSuffix),
+									Value: fmt.Sprintf("%s:%s", pythonPathGlibcPrefix, pythonPathGlibcSuffix),
 								},
 								{
 									Name:  "OTEL_EXPORTER_OTLP_TRACES_PROTOCOL",
@@ -1472,7 +1472,7 @@ func TestMutatePod(t *testing.T) {
 								},
 								{
 									Name:  "PYTHONPATH",
-									Value: fmt.Sprintf("%s:%s", pythonPathPrefix, pythonPathSuffix),
+									Value: fmt.Sprintf("%s:%s", pythonPathGlibcPrefix, pythonPathGlibcSuffix),
 								},
 								{
 									Name:  "OTEL_EXPORTER_OTLP_TRACES_PROTOCOL",
@@ -3743,7 +3743,7 @@ func TestMutatePod(t *testing.T) {
 								},
 								{
 									Name:  "PYTHONPATH",
-									Value: fmt.Sprintf("%s:%s", pythonPathPrefix, pythonPathSuffix),
+									Value: fmt.Sprintf("%s:%s", pythonPathGlibcPrefix, pythonPathGlibcSuffix),
 								},
 								{
 									Name:  "OTEL_TRACES_EXPORTER",
@@ -3806,7 +3806,7 @@ func TestMutatePod(t *testing.T) {
 								},
 								{
 									Name:  "PYTHONPATH",
-									Value: fmt.Sprintf("%s:%s", pythonPathPrefix, pythonPathSuffix),
+									Value: fmt.Sprintf("%s:%s", pythonPathGlibcPrefix, pythonPathGlibcSuffix),
 								},
 								{
 									Name:  "OTEL_TRACES_EXPORTER",
@@ -4401,7 +4401,7 @@ func TestMutatePod(t *testing.T) {
 								},
 								{
 									Name:  "PYTHONPATH",
-									Value: fmt.Sprintf("%s:%s", pythonPathPrefix, pythonPathSuffix),
+									Value: fmt.Sprintf("%s:%s", pythonPathGlibcPrefix, pythonPathGlibcSuffix),
 								},
 								{
 									Name:  "OTEL_TRACES_EXPORTER",
@@ -4464,7 +4464,7 @@ func TestMutatePod(t *testing.T) {
 								},
 								{
 									Name:  "PYTHONPATH",
-									Value: fmt.Sprintf("%s:%s", pythonPathPrefix, pythonPathSuffix),
+									Value: fmt.Sprintf("%s:%s", pythonPathGlibcPrefix, pythonPathGlibcSuffix),
 								},
 								{
 									Name:  "OTEL_TRACES_EXPORTER",

pkg/instrumentation/python.go

@@ -28,14 +28,21 @@ const (
 	envOtelMetricsExporter             = "OTEL_METRICS_EXPORTER"
 	envOtelExporterOTLPTracesProtocol  = "OTEL_EXPORTER_OTLP_TRACES_PROTOCOL"
 	envOtelExporterOTLPMetricsProtocol = "OTEL_EXPORTER_OTLP_METRICS_PROTOCOL"
-	pythonPathPrefix                   = "/otel-auto-instrumentation-python/opentelemetry/instrumentation/auto_instrumentation"
-	pythonPathSuffix                   = "/otel-auto-instrumentation-python"
+	pythonPathGlibcPrefix              = "/otel-auto-instrumentation-python/linux-x64/opentelemetry/instrumentation/auto_instrumentation"
+	pythonPathGlibcSuffix              = "/otel-auto-instrumentation-python/linux-x64"
+	pythonPathMuslPrefix               = "/otel-auto-instrumentation-python/linux-musl-x64/opentelemetry/instrumentation/auto_instrumentation"
+	pythonPathMuslSuffix               = "/otel-auto-instrumentation-python/linux-musl-x64"
 	pythonInstrMountPath               = "/otel-auto-instrumentation-python"
 	pythonVolumeName                   = volumeName + "-python"
 	pythonInitContainerName            = initContainerName + "-python"
 )
 
-func injectPythonSDK(pythonSpec v1alpha1.Python, pod corev1.Pod, index int) (corev1.Pod, error) {
+const (
+	pythonRuntimeLinuxGlibc = "linux-x64"
+	pythonRuntimeLinuxMusl  = "linux-musl-x64"
+)
+
+func injectPythonSDK(pythonSpec v1alpha1.Python, pod corev1.Pod, index int, runtime string) (corev1.Pod, error) {
 	// caller checks if there is at least one container.
 	container := &pod.Spec.Containers[index]
 
@@ -44,6 +51,19 @@ func injectPythonSDK(pythonSpec v1alpha1.Python, pod corev1.Pod, index int) (cor
 		return pod, err
 	}
 
+	pythonPathPrefix := ""
+	pythonPathSuffix := ""
+	switch runtime {
+	case "", pythonRuntimeLinuxGlibc:
+		pythonPathPrefix = pythonPathGlibcPrefix
+		pythonPathSuffix = pythonPathGlibcSuffix
+	case pythonRuntimeLinuxMusl:
+		pythonPathPrefix = pythonPathMuslPrefix
+		pythonPathSuffix = pythonPathMuslSuffix
+	default:
+		return pod, fmt.Errorf("provided instrumentation.opentelemetry.io/otel-python-auto-runtime annotation value '%s' is not supported", runtime)
+	}
+
 	// inject Python instrumentation spec env vars.
 	for _, env := range pythonSpec.Env {
 		idx := getIndexOfEnv(container.Env, env.Name)