GitLab Runner on a Kubernetes cluster

Readme.md

1. Create namespace.yaml

apiVersion: v1
kind: Namespace
metadata:
  name: gitlab

2. kubectl create -f ./namespace.yaml

3. Create configmap.yaml, The token of "CI / CD Settings -> Runners settings" is for gitlab-runner register process. Try gitlab-runner register to get the right token in cofig.toml of local, and change token of config.toml of K8S.

apiVersion: v1
kind: ConfigMap
metadata:
  name: gitlab-runner
  namespace: gitlab
data:
  config.toml: |
    concurrent = 4

    [[runners]]
      name = "Kubernetes Runner"
      url = "https://gitlab.com/ci"
      token = "...."
      executor = "kubernetes"
      [runners.kubernetes]
        namespace = "gitlab"
        image = "busybox"

4. kubectl create -f configmap.yaml

5. Check configmap, kubectl get configmap --all-namespaces=true

6. Create deployment.yaml file

apiVersion: extensions/v1beta1
kind: Deployment
metadata:
  name: gitlab-runner
  namespace: gitlab
spec:
  replicas: 1
  selector:
    matchLabels:
      name: gitlab-runner
  template:
    metadata:
      labels:
        name: gitlab-runner
    spec:
      containers:
      - args:
        - run
        image: gitlab/gitlab-runner:latest
        imagePullPolicy: Always
        name: gitlab-runner
        volumeMounts:
        - mountPath: /etc/gitlab-runner
          name: config
        - mountPath: /etc/ssl/certs
          name: cacerts
          readOnly: true
      restartPolicy: Always
      volumes:
      - configMap:
          name: gitlab-runner
        name: config
      - hostPath:
          path: /usr/share/ca-certificates/mozilla
        name: cacerts

7. kubectl create -f deployment.yaml

going through deployment.yaml, I didn't see any mount volume for source code. Why? based on my understanding, runner will pull the code, check the syntax (per our gitlab_ci.yaml file). Without mounted volume, where store the src code?
Secondly, how gitlab talk to k8s pods? I didn't see any service created. Could anybody pls shine here? thanks

going through deployment.yaml, I didn't see any mount volume for source code. Why? based on my understanding, runner will pull the code, check the syntax (per our gitlab_ci.yaml file). Without mounted volume, where store the src code?

The gitlab-runner deployment/pod is acting like a controller here. Runner will listen for the pipeline/job events and create corresponding build pods. The source code is mounted there. You can check that with kubectl get pods -w watching for newly created build pods, then kubectl get <pod_name> -o yaml.

# ...
    volumeMounts:
    - mountPath: /builds
      name: repo
# ...

Secondly, how gitlab talk to k8s pods? I didn't see any service created. Could anybody pls shine here? thanks

Not sure about that though.