Record AppMap Data in Kubernetes/minikube

If you use minikube to run your application locally for testing and development, you can create and access AppMap data by mounting a volume into your minikube host and making this volume available to your Kubernetes application pod.

If you are unable to mount a directory using minikube, or if your Kubernetes cluster is running remotely in a dev or test environment, you can use alternative techniques such as kubectl cp to copy AppMap data from a pod to your local machine for analysis, or you can leverage Remote Recording of your application instead.

Appmap and minikube Setup

AppMap and minikube Architecture

AppMap and minikube Architecture

Mount AppMap Data Directory into minikube Host

To get direct access to your AppMap data from within your Code Editor with the AppMap plugin you need to use the minikube mount command to map the tmp/appmap directory in your project into your minikube virtual machine.

Note: Mount this directory before you deploy your application pod to ensure the application can write into directory mount.

Refer to the minikube mount documentation for more details and requirements about this feature.

From your local machine, run the following command to map your local AppMap directory to a directory on your minikube host.

$ minikube mount <Local AppMap Dir>:<Remote minikube Dir>

For example, to mount my tmp/appmap directory from my local project to the /appmap-host directory

$ minikube mount tmp/appmap:/appmap-host 
📁  Mounting host path tmp/appmap into VM as /appmap-host ...
    ▪ Mount type:   9p
    ▪ User ID:      docker
    ▪ Group ID:     docker
    ▪ Version:      9p2000.L
    ▪ Message Size: 262144
    ▪ Options:      map[]
    ▪ Bind Address: 127.0.0.1:50300
🚀  Userspace file server: ufs starting
✅  Successfully mounted tmp/appmap to /appmap-host

📌  NOTE: This process must stay alive for the mount to be accessible ...

Connect Shared Volume into Application Pod via hostPath

After you have completed the previous step and mounted your local AppMap data directory into the minikube host, update your pod’s deployment file with a new volumeMounts configuration as well as a hostPath volume.

Add volumeMounts Configuration

In the containers section of the pod’s deployment file, add or append to the volumeMounts section with the full path to the AppMap directory within your application’s working directory.

volumeMounts:
  - name: appmap-dir
    mountPath: <Your application working directory>/tmp/appmap

For example, if your application is running in /usr/src/app, set the mountPath to /usr/src/app/tmp/appmap.

Example:

volumeMounts:
  - name: appmap-dir
    mountPath: /usr/src/app/tmp/appmap

Add a hostPath Volume to the Pod

With the volumeMounts configuration added to your pod’s deployment file, now add or append to your volumes section connecting the volume mount to the minikube host. Use the same directory you defined in the previous section using the minikube mount command

volumeMounts:
  - name: appmap-dir
    mountPath: <Remote minikube Dir>

For example, in the minikube mount command we mounted the tmp/appmap dir to the /appmap-host directory within our minikube host. We’ll set the mountPath equal to the /appmap-host directory.

volumeMounts:
  - name: appmap-dir
    mountPath: /appmap-host

Updated deployment.yml File Example

For a fully working example project example, refer to the AppMap GitHub repo.

apiVersion: apps/v1
kind: Deployment
spec:
  replicas: 1
    spec:
      containers:
        - name: django
          image: petecheslock/django_oscar:latest
          imagePullPolicy: Always
          command: ["/bin/sh"]
          args: ["-c", "python appmap-python sandbox/manage.py runserver 0.0.0.0:8000"]
          ports:
            - containerPort: 8000
          envFrom:
            - configMapRef:
                name: django-config
          resources:
            limits:
              memory: 512Mi
              cpu: "250m"
            requests:
              memory: 512Mi
              cpu: "250m"

+          volumeMounts:
+            - name: appmap-dir
+              mountPath: /usr/src/app/tmp/appmap
+
+      volumes:
+        - name: appmap-dir
+          hostPath:
+            path: /appmap-host

Video Demonstration

Add and Enable AppMap within your Application Pod Configuration

For more information about how to enable your application to create AppMap data, follow the AppMap documentation based on your language and framework.

After adding the AppMap software libraries and other necessary configurations to your application, redeploy your pod with AppMap enabled. After your application starts, use the minikube tunnel command to make a connection to your LoadBalancer services to allow ingress network connections to your application. Refer to the minikube documentation for more details and configuration settings for the tunnel command.

Remote Record Application within Kubernetes Pod

If you are unable to mount a local directory from your machine into your minikube host, you can alternatively run a Remote Recording of your application to generate AppMap Data.

To learn more how Remote Recording works with your application, refer to the AppMap documentation with language specific setup details.

Video Demonstration

Copy AppMap Data from Application Pod to Local Machine

If you are unable to mount a local directory from your machine into your minikube host you can copy files using the kubectl cp command from the container(s) in your application pod to your local machine into the tmp/appmap directory in your project.

First, get the name of the pod you wish to copy files from. Run the kubectl get pods to see a list of available pods.

$ kubectl get pods
NAME                        READY   STATUS    RESTARTS   AGE
django-d84f99988-5hvck      1/1     Running   0          62s
my-nginx-5cd6fb64d5-c86t6   1/1     Running   0          62s
my-nginx-5cd6fb64d5-c8wsm   1/1     Running   0          62s
postgres-64ff95ff77-8hk2m   1/1     Running   0          62s
redis-676d779f49-vnsvf      1/1     Running   0          62s

Then, use the kubectl cp commmand to copy the files to your local tmp/appmap directory.

$ kubectl cp <Namespace>/<Pod Name>:<Remote AppMap Data Dir> <Local AppMap Dir>

For example, to copy all of the generated AppMap data from the Django pod in the example above, run the following command.

$ kubectl cp default/django-7f4dbc8d58-z4xwl:/usr/src/app/tmp/appmap ./tmp/appmap

Refer to the Kubernetes documentation for more details and advanced options for the kubectl cp command.

Was this page helpful? thumb_up Yes thumb_down No
Thank you for your feedback!