Lambda

Quick Reference

# List functions matching a prefix
aws lambda list-functions --query "Functions[?starts_with(FunctionName, 'staging-')].[FunctionName,Runtime,MemorySize,Timeout]" --output table

# Get function config (env vars, role, handler)
aws lambda get-function-configuration --function-name staging-EcomIndexerFunction

# Get recent invocations via CloudWatch Logs
aws logs filter-log-events \
  --log-group-name /aws/lambda/staging-EcomIndexerFunction \
  --start-time $(date -v-15M +%s000) \
  --filter-pattern "ERROR"

# Tail logs live
aws logs tail /aws/lambda/staging-EcomIndexerFunction --follow

# Check recent errors
aws logs filter-log-events \
  --log-group-name /aws/lambda/staging-EcomIndexerFunction \
  --start-time $(date -v-1H +%s000) \
  --filter-pattern "?ERROR ?Traceback ?Exception"

# Check event source mappings (SQS triggers, DDB streams)
aws lambda list-event-source-mappings --function-name staging-EcomIndexerFunction

Function Naming Convention

Two naming conventions coexist:

• Ecom/Admin stack (CDK): {env}-{FunctionName} (e.g., staging-EcomIndexerFunction)
• Controller stack (CDK): {FunctionName}-{env} (e.g., ControllerAuthLambda-staging)
• Cognito triggers (CDK): ControllerCognitoStack-{env_prefix}-{Name}{hash} (auto-generated, find via aws lambda list-functions --query "Functions[?contains(FunctionName, 'PostConfirmation')]")

Key Functions by Component

Function	Purpose	Trigger
{env}-EcomIndexerFunction	Index products into Marqo	SQS (per-shop queues)
{env}-EcomSettingsExporterLambda	Sync settings to Cloudflare KV	DDB Stream on IndexSettingsTable
{env}-EcomMetricsWorker	Process search metrics	SQS (metrics queue)
{env}-EcomMonitoringServiceLambda	Check alarms exist for indexes	EventBridge (every 10 min)
{env}-ShopifyAppAdminFunction	Shopify admin API	API Gateway
{env}-ShopifyWebhookWorker	Async webhook processing	Invoked by Admin Function
{env}-AdminLambda	Admin dashboard API	API Gateway
MerchandisingExporterLambda-{env}	Sync merchandising to CF KV	EventBridge (every 5 min)
ControllerAuthLambda-{env}	Auth for controller API	API Gateway authorizer

What to Look For

Symptom	Check
Function errors	aws logs filter-log-events with ERROR filter on the function's log group
Timeout	Check Timeout in function config vs actual duration in logs
Throttling	Check CloudWatch metric Throttles for the function
SQS not draining	Check event source mapping state: aws lambda list-event-source-mappings
DDB stream backlog	Check IteratorAge metric on the settings exporter