Chapter 6. Automatically injecting sidecars

To enable this feature, you add the annotation sidecar.jaegertracing.io/inject set to either the string true or the Jaeger instance name as returned by oc get jaegers. When you specify true, there should be only a single Jaeger instance for the same namespace as the deployment, otherwise, the Operator cannot determine which Jaeger instance to use. A specific Jaeger instance name on a deployment has a higher precedence than true applied on its namespace.

The following snippet shows a simple application that will inject a sidecar, with the Jaeger Agent pointing to the single Jaeger instance available in the same namespace:

apiVersion: apps/v1
kind: Deployment
metadata:
  name: myapp
  annotations:
    "sidecar.jaegertracing.io/inject": "true" 
spec:
  selector:
    matchLabels:
      app: myapp
  template:
    metadata:
      labels:
        app: myapp
    spec:
      containers:
      - name: myapp
        image: acme/myapp:myversion

apiVersion: apps/v1
kind: Deployment
metadata:
  name: myapp
  annotations:
    "sidecar.jaegertracing.io/inject": "true" 

spec:
  selector:
    matchLabels:
      app: myapp
  template:
    metadata:
      labels:
        app: myapp
    spec:
      containers:
      - name: myapp
        image: acme/myapp:myversion

When the sidecar is injected, the Jaeger Agent can then be accessed at its default location on localhost.