# VS Code in the browser (code-server) in a Nitro sandbox, on a persistent EBS workspace. # # One agent-sandbox Sandbox. Its pod runs the prebuilt code-server image as a # non-root user, serves the VS Code workbench on port 8080 inside the guest, and # keeps the project folder on an Amazon EBS volume from volumeClaimTemplates. # # Nothing publishes that port outside the cluster: there is no Ingress, no # LoadBalancer and no NodePort anywhere in this sample. service: true asks the # controller for a headless ClusterIP Service, and the way in is # `kubectl port-forward` from the operator's own machine. The egress policy # refuses every connection from the pod network; see its header for the one # thing a network policy cannot deny, the pod's own node. # # The editor's password is an argon2 hash the operator generated on their own # machine, held in the Kubernetes Secret named below. The pod spec carries only a # reference to it: no password and no hash appear in this file. # # __NAMESPACE__, __STORAGE_CLASS__ and __IMAGE__ are filled in at apply time by # scripts/setup.sh, so an overridden name reaches this object too. Never apply # this file with the placeholders in place. apiVersion: agents.x-k8s.io/v1beta1 kind: Sandbox metadata: name: ide namespace: __NAMESPACE__ labels: app.kubernetes.io/name: ide spec: # Ask the controller for the Sandbox's headless Service, so the editor has a # stable in-cluster name. It is a ClusterIP Service with no cluster IP, which # publishes nothing outside the cluster. service: true podTemplate: metadata: labels: app.kubernetes.io/name: ide # The egress network policy selects the pod by this label. app: ide annotations: # The workspace claim is ReadWriteOncePod, so the EBS volume is attached # to one node at a time. Pin the node while the pod runs, so Auto Mode # does not consolidate it out from under the attachment. karpenter.sh/do-not-disrupt: "true" spec: # The one line that puts the pod in a Nitro sandbox. No node selector, # toleration or sidecar: the RuntimeClass carries the scheduling # constraints, and EKS Auto Mode brings up a sandbox-capable node. runtimeClassName: isolated-sandbox # The editor calls no Kubernetes API, so it mounts no ServiceAccount token. automountServiceAccountToken: false securityContext: # code-server runs as uid 1000 (coder) in this image. runAsUser pins that # identity, and runAsNonRoot makes "never root" explicit: the kubelet # refuses to start the container if the image would resolve to root. runAsNonRoot: true runAsUser: 1000 runAsGroup: 1000 # A freshly provisioned EBS volume mounts as root:root 0755. fsGroup has # the kubelet set the volume's group owner and make it group-writable on # mount, so uid 1000 can write the workspace with no init container and # no privileged container. fsGroup: 1000 seccompProfile: type: RuntimeDefault containers: - name: code-server image: __IMAGE__ imagePullPolicy: IfNotPresent # The image's entrypoint runs code-server with its own default flags # appended ("--bind-addr 0.0.0.0:8080 ."). Naming the entrypoint here # replaces those defaults with the flags below, so the command line the # editor runs with is exactly this and nothing is passed twice. command: ["/usr/bin/entrypoint.sh"] args: # Listen on the pod's own interface inside the guest, not only on the # guest's loopback: a kubectl port-forward stream reaches the editor # from the pod's own node, which code-server logs as a connection # from the node's address, so the socket has to accept the pod's # address too. Nothing publishes the port outside the cluster, and # the egress policy denies all ingress from the pod network, so the # port-forward tunnel is the way in. - --bind-addr=0.0.0.0:8080 # Keep the editor off the network it does not need: no telemetry and # no update check, so the egress policy has fewer hosts to allow. - --disable-telemetry - --disable-update-check # The folder the workbench opens, which is the EBS workspace below. - /home/coder/project env: # code-server reads the argon2 hash from this variable and prefers it # over a plaintext password (code-server FAQ, "Can I store my password # hashed?"). The value comes from the Secret, so the hash is not in # this file; the plaintext never leaves the operator's machine. - name: HASHED_PASSWORD valueFrom: secretKeyRef: name: ide-password key: hashed-password ports: - name: http containerPort: 8080 readinessProbe: # Ready on the Sandbox means its pod is Ready, and an IDE takes longer # to serve than it takes to start. Gate Ready on code-server's own # /healthz endpoint, so `kubectl wait` waits for a serving editor. # The kubelet probes from the node, which Kubernetes always allows # even with all ingress denied. httpGet: path: /healthz port: http periodSeconds: 5 failureThreshold: 60 volumeMounts: # This name matches the volumeClaimTemplates entry below. The # controller synthesizes the pod volume; do not add a matching # spec.volumes entry yourself. - name: workspace mountPath: /home/coder/project resources: # The guest VM is sized from the pod's requests, and the small # default guest is not enough for an IDE: code-server's Node.js # server plus the workbench's extension host need the memory below. # Most samples on this site set no requests at all. requests: memory: 2Gi securityContext: # The sandbox already runs this pod in its own VM; these keep the # container itself least-privileged. Nothing here builds an image, so # no capability and no privileged container is needed. A variant that # built a devcontainer at boot would need root and privileged, which # is the contrast the page draws. allowPrivilegeEscalation: false capabilities: drop: ["ALL"] # volumeClaimTemplates is immutable after the Sandbox is created (CEL-validated # on the CRD). Changing the size, class or access mode means deleting and # recreating the Sandbox, which deletes the workspace. volumeClaimTemplates: - metadata: name: workspace labels: app.kubernetes.io/name: ide spec: accessModes: # ReadWriteOncePod, not ReadWriteOnce: only one pod may mount the # workspace at a time. Plain ReadWriteOnce promises only one node, so # two pods on that node could mount the same workspace together. - ReadWriteOncePod # The class setup chose, rendered in here at apply time. A StorageClass is # chosen, never changed: setup uses the cluster's default when exactly one # fits (ebs.csi.eks.amazonaws.com, gp3, encrypted), otherwise the sample's # own class ide-gp3 from deploy/storage-class.yaml. storageClassName: __STORAGE_CLASS__ resources: requests: # Rendered from WORKSPACE_SIZE at apply time, which is also the value # setup compares with an existing Sandbox's claim template. storage: __STORAGE_SIZE__ # The resulting PVC is named "