使用 yq 编辑 YAML 配置文件

# Install yq (Go version) on Linux
wget -q https://github.com/mikefarah/yq/releases/latest/download/yq_linux_amd64 \
  -O /usr/local/bin/yq
chmod +x /usr/local/bin/yq

# Confirm version
yq --version

# Create a sample deployment YAML
cat > /tmp/deployment.yaml << 'EOF'
apiVersion: apps/v1
kind: Deployment
metadata:
  name: my-app
  namespace: production
spec:
  replicas: 3
  template:
    spec:
      containers:
        - name: app
          image: my-app:1.0.0
EOF

# Read individual fields
echo "App name:    $(yq '.metadata.name' /tmp/deployment.yaml)"
echo "Replicas:    $(yq '.spec.replicas' /tmp/deployment.yaml)"
echo "Image:       $(yq '.spec.template.spec.containers[0].image' /tmp/deployment.yaml)"

# Start with the deployment from the previous scene
echo 'Before:' && yq '.spec.replicas' /tmp/deployment.yaml

# Edit in place: scale to 5 replicas
yq -i '.spec.replicas = 5' /tmp/deployment.yaml

echo 'After:' && yq '.spec.replicas' /tmp/deployment.yaml

NEW_TAG="my-app:2.1.0"
CONTAINER_NAME="app"

# Robust update: target by container name, not index
yq -i \
  "(.spec.template.spec.containers[] | select(.name == \"${CONTAINER_NAME}\")).image = \"${NEW_TAG}\"" \
  /tmp/deployment.yaml

# Verify
yq '.spec.template.spec.containers[0].image' /tmp/deployment.yaml

# Add a label to the deployment
yq -i '.metadata.labels.version = "v2"' /tmp/deployment.yaml
yq -i '.metadata.labels.managed-by = "ci-pipeline"' /tmp/deployment.yaml

echo '--- Labels after adding ---'
yq '.metadata.labels' /tmp/deployment.yaml

# Delete one label
yq -i 'del(.metadata.labels.managed-by)' /tmp/deployment.yaml

echo '--- Labels after delete ---'
yq '.metadata.labels' /tmp/deployment.yaml

cat > /tmp/multi.yaml << 'EOF'
apiVersion: apps/v1
kind: Deployment
metadata:
  name: web
spec:
  replicas: 1
---
apiVersion: v1
kind: Service
metadata:
  name: web-svc
spec:
  port: 80
EOF

# Scale ONLY the Deployment, leave Service untouched
yq -i 'select(.kind == "Deployment").spec.replicas = 4' /tmp/multi.yaml

echo '--- Deployment replicas ---'
yq 'select(.kind == "Deployment").spec.replicas' /tmp/multi.yaml

echo '--- Service port (unchanged) ---'
yq 'select(.kind == "Service").spec.port' /tmp/multi.yaml

cat > /tmp/ci.yml << 'EOF'
name: CI
on: [push]
jobs:
  build:
    runs-on: ubuntu-22.04
    steps:
      - uses: actions/checkout@v3
      - uses: actions/setup-node@v3
        with:
          node-version: 18
      - run: npm test
  lint:
    runs-on: ubuntu-22.04
    steps:
      - uses: actions/checkout@v3
      - run: npm run lint
EOF

# Bump all checkout steps from v3 → v4
yq -i '(.jobs[].steps[] | select(.uses == "actions/checkout@v3")).uses = "actions/checkout@v4"' \
  /tmp/ci.yml

# Verify both jobs were updated
yq '.jobs[].steps[] | select(.uses | test("checkout")).uses' /tmp/ci.yml

export APP_IMAGE="my-app:3.0.0"
export REPLICA_COUNT=6

# Set image using strenv() — result is a YAML string
yq -i '.spec.template.spec.containers[0].image = strenv(APP_IMAGE)' \
  /tmp/deployment.yaml

# Set replicas using env() — result is a YAML integer
yq -i '.spec.replicas = env(REPLICA_COUNT)' \
  /tmp/deployment.yaml

# Confirm types are correct in the output
yq '.spec.replicas, .spec.template.spec.containers[0].image' /tmp/deployment.yaml

cat > /tmp/base.yaml << 'EOF'
app:
  name: my-service
  port: 8080
  debug: false
database:
  host: localhost
  port: 5432
EOF

cat > /tmp/patch.yaml << 'EOF'
app:
  port: 9090
  debug: true
database:
  host: db.production.svc
EOF

# Deep-merge patch into base (stdout preview first)
yq '. *= load("/tmp/patch.yaml")' /tmp/base.yaml

# Apply in place
yq -i '. *= load("/tmp/patch.yaml")' /tmp/base.yaml

# Validate YAML (exits 0 on success, 1 on parse error)
if yq '.' /tmp/deployment.yaml > /dev/null 2>&1; then
  echo "YAML is valid"
else
  echo "YAML parse error!" >&2
  exit 1
fi

# Convert to JSON and query with jq
yq -o=json '.' /tmp/deployment.yaml \
  | jq '{name: .metadata.name, image: .spec.template.spec.containers[0].image}'

# Round-trip: JSON snippet back to YAML
echo '{"replicas": 7, "strategy": "RollingUpdate"}' \
  | yq -P '.'

#!/usr/bin/env bash
set -euo pipefail

MANIFEST="/tmp/deployment.yaml"
export NEW_IMAGE="my-app:$(date +%Y%m%d)-abc1234"
export NEW_REPLICAS=3
export DEPLOY_TIME="$(date -u +%Y-%m-%dT%H:%M:%SZ)"
export CONTAINER="app"

# 1. Validate before patching
yq '.' "$MANIFEST" > /dev/null

# 2. Update image (by container name)
yq -i \
  '(.spec.template.spec.containers[] | select(.name == strenv(CONTAINER))).image = strenv(NEW_IMAGE)' \
  "$MANIFEST"

# 3. Set replicas
yq -i '.spec.replicas = env(NEW_REPLICAS)' "$MANIFEST"

# 4. Stamp annotation
yq -i '.metadata.annotations."deploy-time" = strenv(DEPLOY_TIME)' "$MANIFEST"

# 5. Validate result
yq '.' "$MANIFEST" > /dev/null && echo "Patch applied successfully"

# 6. Show diff summary
yq '{image: .spec.template.spec.containers[0].image, replicas: .spec.replicas}' "$MANIFEST"