kubernetes-mcp-server

#!/bin/bash # A more robust script header # exit on any error, exit on undeclared variable, and fail pipe commands on the first error set -euo pipefail # All variables are defined here for easy modification NAMESPACE="canary-deployment-ns" CANARY_DEPLOYMENT="engine-v2-1" STABLE_DEPLOYMENT="engine-v2-0" SERVICE="recommendation-engine" CANARY_IMAGE="nginx:1.29" CANARY_REPLICAS=2 STABLE_REPLICAS=2 EXPECTED_TOTAL_ENDPOINTS=$((CANARY_REPLICAS + STABLE_REPLICAS)) TIMEOUT="120s" # Wait for both deployments to be available and fully rolled out if ! kubectl wait deployment "$CANARY_DEPLOYMENT" -n "$NAMESPACE" \ --for=condition=Available=true \ --timeout="$TIMEOUT"; then echo "ERROR: Failed to find available canary deployment: '$CANARY_DEPLOYMENT'." exit 1 fi if ! kubectl wait deployment "$CANARY_DEPLOYMENT" -n "$NAMESPACE" \ --for=condition=Available=true \ --for=jsonpath="{.status.updatedReplicas}=${CANARY_REPLICAS}" \ --timeout="$TIMEOUT"; then echo "ERROR: Canary deployment does not have the correct amount of replicas." exit 1 fi if ! kubectl wait deployment "$STABLE_DEPLOYMENT" -n "$NAMESPACE" \ --for=condition=Available=true \ --for=jsonpath="{.status.updatedReplicas}=${STABLE_REPLICAS}" \ --timeout="$TIMEOUT"; then echo "ERROR: Stable deployment does not have the correct amount of replicas." exit 1 fi # Verify the canary deployment is using the correct container image CURRENT_CANARY_IMAGE=$(kubectl get deployment "$CANARY_DEPLOYMENT" -n "$NAMESPACE" -o jsonpath='{.spec.template.spec.containers[0].image}') if [[ "$CURRENT_CANARY_IMAGE" != "$CANARY_IMAGE" ]]; then echo "ERROR: Canary deployment image is '$CURRENT_CANARY_IMAGE', expected '$CANARY_IMAGE'." exit 1 fi # Verify the service selector targets the general app label without a version SERVICE_JSON=$(kubectl get svc "$SERVICE" -n "$NAMESPACE" -o json) SELECTOR_APP=$(echo "$SERVICE_JSON" | jq -r '.spec.selector.app') # 'jq' will output the string 'null' if the key doesn't exist SELECTOR_VERSION=$(echo "$SERVICE_JSON" | jq -r '.spec.selector.version') if [[ "$SELECTOR_APP" != "$SERVICE" ]] || [[ "$SELECTOR_VERSION" != "null" ]]; then echo "ERROR: Service selector is incorrect. It should only target 'app: $SERVICE'." echo " Found: app='$SELECTOR_APP', version='$SELECTOR_VERSION'" exit 1 fi # Wait until the service has endpoints for all pods (stable + canary) to confirm traffic is flowing to all expected pods echo "--> Waiting for service '$SERVICE' to have '$EXPECTED_TOTAL_ENDPOINTS' endpoints..." success=false # This loop will try 18 times, waiting 5 seconds between each attempt (90s total timeout) for i in {1..18}; do # Using jq for a readable and robust way to count ready addresses. count=$(kubectl get endpoints "$SERVICE" -n "$NAMESPACE" -o json 2>/dev/null | jq '([.subsets[].addresses // [] | length] | add) // 0' || echo 0) if [[ "$count" -eq "$EXPECTED_TOTAL_ENDPOINTS" ]]; then echo "Success: Service has all $count endpoints." success=true break fi echo " ($i/18) Waiting... found $count endpoints. Retrying in 5 seconds..." sleep 5 done if ! $success; then echo "ERROR: Timed out waiting for service endpoints." echo " Found $count endpoints, but expected $EXPECTED_TOTAL_ENDPOINTS." exit 1 fi echo "--- Verification Successful! ---" echo "Canary deployment is correctly configured and receiving traffic." exit 0