Instrumentations support select

.chloggen/instrumentation-support-select.yaml

@@ -0,0 +1,16 @@
+# One of 'breaking', 'deprecation', 'new_component', 'enhancement', 'bug_fix'
+change_type: enhancement
+
+# The name of the component, or a single word describing the area of concern, (e.g. collector, target allocator, auto-instrumentation, opamp, github action)
+component: auto-instrumentation
+
+# A brief description of the change. Surround your text with quotes ("") if it needs to start with a backtick (`).
+note: Instrumentations support select
+
+# One or more tracking issues related to the change
+issues: [2744]
+
+# (Optional) One or more lines of additional information to render under the primary note.
+# These lines will be padded with 2 spaces and then inserted directly into the document.
+# Use pipe (|) for multiline entries.
+subtext:

apis/v1alpha1/instrumentation_types.go

@@ -22,6 +22,10 @@ import (
 
 // InstrumentationSpec defines the desired state of OpenTelemetry SDK and instrumentation.
 type InstrumentationSpec struct {
+	// Selector is the selector label of injected Object
+	// +optional
+	Selector map[string]string `json:"selector,omitempty"`
+
 	// Exporter defines exporter configuration.
 	// +optional
 	Exporter `json:"exporter,omitempty"`

bundle/manifests/opentelemetry.io_instrumentations.yaml

@@ -1027,6 +1027,10 @@ spec:
                     - xray
                     type: string
                 type: object
+              selector:
+                additionalProperties:
+                  type: string
+                type: object
             type: object
           status:
             type: object

config/crd/bases/opentelemetry.io_instrumentations.yaml

@@ -1025,6 +1025,10 @@ spec:
                     - xray
                     type: string
                 type: object
+              selector:
+                additionalProperties:
+                  type: string
+                type: object
             type: object
           status:
             type: object

docs/api.md

@@ -172,6 +172,13 @@ Resource Types:
           <br/>
         </td>
         <td>false</td>
+      </tr><tr>
+        <td><b>selector</b></td>
+        <td>map[string]string</td>
+        <td>
+          <br/>
+        </td>
+        <td>false</td>
       </tr></tbody>
 </table>
 

pkg/instrumentation/podmutator.go

@@ -33,8 +33,7 @@ import (
 )
 
 var (
-	errMultipleInstancesPossible = errors.New("multiple OpenTelemetry Instrumentation instances available, cannot determine which one to select")
-	errNoInstancesAvailable      = errors.New("no OpenTelemetry Instrumentation instances available")
+	errNoInstancesAvailable = errors.New("no OpenTelemetry Instrumentation instances available")
 )
 
 type instPodMutator struct {
@@ -373,7 +372,7 @@ func (pm *instPodMutator) getInstrumentationInstance(ctx context.Context, ns cor
 	}
 
 	if strings.EqualFold(instValue, "true") {
-		return pm.selectInstrumentationInstanceFromNamespace(ctx, ns)
+		return pm.selectInstrumentationInstanceFromNamespace(ctx, ns, pod)
 	}
 
 	var instNamespacedName types.NamespacedName
@@ -392,18 +391,32 @@ func (pm *instPodMutator) getInstrumentationInstance(ctx context.Context, ns cor
 	return otelInst, nil
 }
 
-func (pm *instPodMutator) selectInstrumentationInstanceFromNamespace(ctx context.Context, ns corev1.Namespace) (*v1alpha1.Instrumentation, error) {
+func (pm *instPodMutator) selectInstrumentationInstanceFromNamespace(ctx context.Context, ns corev1.Namespace, pod corev1.Pod) (*v1alpha1.Instrumentation, error) {
 	var otelInsts v1alpha1.InstrumentationList
 	if err := pm.Client.List(ctx, &otelInsts, client.InNamespace(ns.Name)); err != nil {
 		return nil, err
 	}
 
-	switch s := len(otelInsts.Items); {
+	// selector
+	var availableInstrument []v1alpha1.Instrumentation
+	for _, ins := range otelInsts.Items {
+		isMatch := true
+		if len(ins.Spec.Selector) != 0 {
+			for k, v := range ins.Spec.Selector {
+				if !strings.EqualFold(v, pod.Labels[k]) {
+					isMatch = false
+				}
+			}
+		}
+		if isMatch {
+			availableInstrument = append(availableInstrument, ins)
+		}
+	}
+
+	switch s := len(availableInstrument); {
 	case s == 0:
 		return nil, errNoInstancesAvailable
-	case s > 1:
-		return nil, errMultipleInstancesPossible
 	default:
-		return &otelInsts.Items[0], nil
+		return &availableInstrument[len(availableInstrument)-1], nil
 	}
 }