helm: ability to set hostAliases on browser node deployments

[anthonybaldwin]

Description

• Add the ability to set hostAliases on browser node deployments

Motivation and Context

• App requires host entries to avoid hitting Cloudflare, so I am manually making these changes to alter every chart release
• With this change, should be able to pass in using --set (if you can figure out the syntax...) or custom-values.yaml instead
  • Or to not change at all...

Types of changes

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to change)

Checklist

• I have read the contributing document.
• My change requires a change to the documentation.
• I have updated the documentation accordingly.
• I have added tests to cover my changes.
• All new and existing tests passed.

[CLAassistant]

All committers have signed the CLA.

[anthonybaldwin]

The below may help check the change using my branch.

(Note: The force push is because I concluded 123. is bad; used documentation IPs instead. Open to replacing with hosts ending in .example if preferred, but I'm impartial.)

Save values-user.yaml to docker-selenium root:

chromeNode:
  hostAliases:
    - ip: "198.51.100.0"
      hostnames:
        - "example.com"
        - "example.net"
    - ip: "203.0.113.0"
      hostnames:
        - "example.org"
edgeNode:
  hostAliases:
    - ip: "198.51.100.0"
      hostnames:
        - "example.com"
        - "example.net"
    - ip: "203.0.113.0"
      hostnames:
        - "example.org"
firefoxNode:
  hostAliases:
    - ip: "198.51.100.0"
      hostnames:
        - "example.com"
        - "example.net"
    - ip: "203.0.113.0"
      hostnames:
        - "example.org"

Run this:

helm install selenium-grid \
  --values values-user.yaml \
  charts/selenium-grid/. \
  --dry-run --debug

The output browser deployment yamls (trimmed the rest to save space):

# Source: selenium-grid/templates/chrome-node-deployment.yaml
apiVersion: apps/v1
kind: Deployment
metadata:
  name: selenium-chrome-node
  namespace: localdev
  labels: &chrome_node_labels
    app: selenium-chrome-node
    app.kubernetes.io/name: selenium-chrome-node
    app.kubernetes.io/managed-by: helm
    app.kubernetes.io/instance: selenium-grid
    app.kubernetes.io/version: 4.2.1-20220531
    app.kubernetes.io/component: selenium-grid-4.2.1-20220531
    helm.sh/chart: selenium-grid-0.3.1
spec:
  replicas: 1
  selector:
    matchLabels:
      app: selenium-chrome-node
  template:
    metadata:
      labels: *chrome_node_labels
      annotations:
        checksum/event-bus-configmap: dd260b62645a68911eccf59059c303dc74093e3722f57bc0bb69a49d63f11ecb
    spec:
      hostAliases: 
        - hostnames:
          - example.com
          - example.net
          ip: 198.51.100.0
        - hostnames:
          - example.org
          ip: 203.0.113.0
      containers:
        - name: selenium-chrome-node
          image: selenium/node-chrome:4.2.1-20220531
          imagePullPolicy: IfNotPresent
          envFrom:
            - configMapRef:
                name: selenium-event-bus-config
          ports:
            - containerPort: 5553
              protocol: TCP
          volumeMounts:
            - name: dshm
              mountPath: /dev/shm
          resources:
            limits:
              cpu: "1"
              memory: 1Gi
            requests:
              cpu: "1"
              memory: 1Gi
      volumes:
        - name: dshm
          emptyDir:
            medium: Memory
            sizeLimit: 1Gi
---
# Source: selenium-grid/templates/edge-node-deployment.yaml
apiVersion: apps/v1
kind: Deployment
metadata:
  name: selenium-edge-node
  namespace: localdev
  labels: &edge_node_labels
    app: selenium-edge-node
    app.kubernetes.io/name: selenium-edge-node
    app.kubernetes.io/managed-by: helm
    app.kubernetes.io/instance: selenium-grid
    app.kubernetes.io/version: 4.2.1-20220531
    app.kubernetes.io/component: selenium-grid-4.2.1-20220531
    helm.sh/chart: selenium-grid-0.3.1
spec:
  replicas: 1
  selector:
    matchLabels:
      app: selenium-edge-node
  template:
    metadata:
      labels: *edge_node_labels
      annotations:
        checksum/event-bus-configmap: dd260b62645a68911eccf59059c303dc74093e3722f57bc0bb69a49d63f11ecb
    spec:
      hostAliases: 
        - hostnames:
          - example.com
          - example.net
          ip: 198.51.100.0
        - hostnames:
          - example.org
          ip: 203.0.113.0
      containers:
        - name: selenium-edge-node
          image: selenium/node-edge:4.2.1-20220531
          imagePullPolicy: IfNotPresent
          envFrom:
            - configMapRef:
                name: selenium-event-bus-config
          ports:
            - containerPort: 5553
              protocol: TCP
          volumeMounts:
            - name: dshm
              mountPath: /dev/shm
          resources:
            limits:
              cpu: "1"
              memory: 1Gi
            requests:
              cpu: "1"
              memory: 1Gi
      volumes:
        - name: dshm
          emptyDir:
            medium: Memory
            sizeLimit: 1Gi
---
# Source: selenium-grid/templates/firefox-node-deployment.yaml
apiVersion: apps/v1
kind: Deployment
metadata:
  name: selenium-firefox-node
  namespace: localdev
  labels: &firefox_node_labels
    app: selenium-firefox-node
    app.kubernetes.io/name: selenium-firefox-node
    app.kubernetes.io/managed-by: helm
    app.kubernetes.io/instance: selenium-grid
    app.kubernetes.io/version: 4.2.1-20220531
    app.kubernetes.io/component: selenium-grid-4.2.1-20220531
    helm.sh/chart: selenium-grid-0.3.1
spec:
  replicas: 1
  selector:
    matchLabels:
      app: selenium-firefox-node
  template:
    metadata:
      labels: *firefox_node_labels
      annotations:
        checksum/event-bus-configmap: dd260b62645a68911eccf59059c303dc74093e3722f57bc0bb69a49d63f11ecb
    spec:
      hostAliases: 
        - hostnames:
          - example.com
          - example.net
          ip: 198.51.100.0
        - hostnames:
          - example.org
          ip: 203.0.113.0
      containers:
        - name: selenium-firefox-node
          image: selenium/node-firefox:4.2.1-20220531
          imagePullPolicy: IfNotPresent
          envFrom:
            - configMapRef:
                name: selenium-event-bus-config
          ports:
            - containerPort: 5553
              protocol: TCP
          volumeMounts:
            - name: dshm
              mountPath: /dev/shm
          resources:
            limits:
              cpu: "1"
              memory: 1Gi
            requests:
              cpu: "1"
              memory: 1Gi
      volumes:
        - name: dshm
          emptyDir:
            medium: Memory
            sizeLimit: 1Gi
...

Matches example here (minus IP/hostnames being re-ordered, but works either way): https://kubernetes.io/docs/tasks/network/customize-hosts-file-for-pods/#adding-additional-entries-with-hostaliases

To confirm on pods (disclude --dry-run --debug on helm install):

trunk kubectl exec selenium-chrome-node-f5d78774b-lgkcx -- cat /etc/hosts
# Kubernetes-managed hosts file.
127.0.0.1	localhost
::1	localhost ip6-localhost ip6-loopback
fe00::0	ip6-localnet
fe00::0	ip6-mcastprefix
fe00::1	ip6-allnodes
fe00::2	ip6-allrouters
10.88.1.23	selenium-chrome-node-f5d78774b-lgkcx

# Entries added by HostAliases.
198.51.100.0	example.com	example.net
203.0.113.0	example.org

trunk kubectl exec selenium-edge-node-7b5d87cd5d-x96l5 -- cat /etc/hosts
# Kubernetes-managed hosts file.
127.0.0.1	localhost
::1	localhost ip6-localhost ip6-loopback
fe00::0	ip6-localnet
fe00::0	ip6-mcastprefix
fe00::1	ip6-allnodes
fe00::2	ip6-allrouters
10.88.1.22	selenium-edge-node-7b5d87cd5d-x96l5

# Entries added by HostAliases.
198.51.100.0	example.com	example.net
203.0.113.0	example.org

trunk kubectl exec selenium-firefox-node-66fb654d78-kszxp -- cat /etc/hosts
# Kubernetes-managed hosts file.
127.0.0.1	localhost
::1	localhost ip6-localhost ip6-loopback
fe00::0	ip6-localnet
fe00::0	ip6-mcastprefix
fe00::1	ip6-allnodes
fe00::2	ip6-allrouters
10.88.0.23	selenium-firefox-node-66fb654d78-kszxp

# Entries added by HostAliases.
198.51.100.0	example.com	example.net
203.0.113.0	example.org

[anthonybaldwin]

Friendly bump on this @ilpianista @diemol

[diemol]

Could you please also update Chart.yaml and the CHANGELOG so we can release right away?

[anthonybaldwin]

Done 👍

[diemol]

Thank you, @anthonybaldwin!