Execute fast smoke tests validating critical functionality after deployment.
Use when performing specialized testing.
Trigger with phrases like "run smoke tests", "quick validation", or "test critical paths".
Execute fast, high-confidence smoke tests that validate critical application functionality after deployment or build. Smoke tests verify that the application starts, core user flows work, and key integrations respond -- without running the full test suite.
Prerequisites
Application deployed and accessible at a known URL or running locally
HTTP client available (curl, wget, node-fetch, or Playwright)
List of critical endpoints and user flows to validate
Expected response codes and content patterns for each check
CI/CD pipeline hook for post-deployment validation
Instructions
Identify the critical paths that constitute a "working" application:
Health check endpoint returns 200 with expected body.
Homepage loads and contains key UI elements.
Authentication flow succeeds with test credentials.
Primary API endpoint returns valid data.
Database connection is active and responding.
Create a smoke test configuration listing each check:
URL or command to execute.
Expected HTTP status code (200, 301, etc.).
Response body pattern to match (substring or regex).
Maximum acceptable response time (e.g., 3 seconds).
Write the smoke test suite as a lightweight script or test file:
Use curl for HTTP checks or Playwright for browser-based checks.
Run checks sequentially for simplicity (parallel for speed if independent).
Fail fast on the first critical failure.
Log each check result with pass/fail, response time, and status code.
Implement timeout guards:
Set a global timeout of 60 seconds for the entire smoke suite.
Set per-check timeouts of 5-10 seconds.
Treat timeouts as failures, not retries.
Add deployment-gate integration:
On success: proceed with deployment promotion or traffic shifting.
On failure: trigger rollback and send alert notification.
Report results to CI/CD dashboard and Slack/Teams webhook.
Store smoke test results as CI artifacts for audit trail.
Schedule periodic smoke runs (every 5 minutes in production) as synthetic monitoring.
Output
Smoke test script (scripts/smoke-test.sh or tests/smoke.test.ts)
Pass/fail result for each critical check with response times
Deployment gate verdict (PASS or FAIL with reason)
CI artifact with timestamped smoke test log
Alert payload for failed checks (Slack webhook, PagerDuty, etc.)
Error Handling
Error
Cause
Solution
Connection refused
Application not yet ready after deployment
Add a startup wait with exponential backoff (max 30 seconds) before running smoke tests
503 Service Unavailable
Application is starting or behind a load balancer draining
Retry with 2-second delay up to 3 times; check load balancer health check status
Unexpected redirect (301/302)
URL changed or SSL redirect not accounted for
Follow redirects with curl -L; update expected URLs in smoke config
Content mismatch
Page content changed but smoke test pattern is too specific
Use broad patterns (check for <title> or key element IDs, not exact text)
Timeout on database check
Database migration running or connection pool exhausted
Increase timeout for database checks; verify migration completed before smoke tests
Examples
Shell-based smoke test script:
#!/bin/bash
set -e
BASE_URL="${1:-http://localhost:3000}" # 3000: 3 seconds in ms
PASS=0; FAIL=0
check() {
local name="$1" url="$2" expected="$3"
status=$(curl -s -o /dev/null -w '%{http_code}' --max-time 5 "$url")
if [ "$status" = "$expected" ]; then
echo "PASS: $name (HTTP $status)"
((PASS++))
else
echo "FAIL: $name (expected $expected, got $status)"
((FAIL++))
fi
}
check "Health check" "$BASE_URL/health" "200" # HTTP 200 OK
check "Homepage" "$BASE_URL/" "200" # HTTP 200 OK
check "API status" "$BASE_URL/api/status" "200" # HTTP 200 OK
check "Login page" "$BASE_URL/login" "200" # HTTP 200 OK
echo "Results: $PASS passed, $FAIL failed"
[ "$FAIL" -eq 0 ] || exit 1