func handleInvoke()

in lambda/invoke_loop.go [46:102]
44 lines of code
10 McCabe index (conditional complexity)

func handleInvoke(invoke *invoke, handler *handlerOptions) error {
	// set the deadline
	deadline, err := parseDeadline(invoke)
	if err != nil {
		return reportFailure(invoke, lambdaErrorResponse(err))
	}
	ctx, cancel := context.WithDeadline(handler.baseContext, deadline)
	defer cancel()

	// set the invoke metadata values
	lc := lambdacontext.LambdaContext{
		AwsRequestID:       invoke.id,
		InvokedFunctionArn: invoke.headers.Get(headerInvokedFunctionARN),
	}
	if err := parseClientContext(invoke, &lc.ClientContext); err != nil {
		return reportFailure(invoke, lambdaErrorResponse(err))
	}
	if err := parseCognitoIdentity(invoke, &lc.Identity); err != nil {
		return reportFailure(invoke, lambdaErrorResponse(err))
	}
	ctx = lambdacontext.NewContext(ctx, &lc)

	// set the trace id
	traceID := invoke.headers.Get(headerTraceID)
	os.Setenv("_X_AMZN_TRACE_ID", traceID)
	// nolint:staticcheck
	ctx = context.WithValue(ctx, "x-amzn-trace-id", traceID)

	// call the handler, marshal any returned error
	response, invokeErr := callBytesHandlerFunc(ctx, invoke.payload, handler.handlerFunc)
	if invokeErr != nil {
		if err := reportFailure(invoke, invokeErr); err != nil {
			return err
		}
		if invokeErr.ShouldExit {
			return fmt.Errorf("calling the handler function resulted in a panic, the process should exit")
		}
		return nil
	}
	// if the response needs to be closed (ex: net.Conn, os.File), ensure it's closed before the next invoke to prevent a resource leak
	if response, ok := response.(io.Closer); ok {
		defer response.Close()
	}

	// if the response defines a content-type, plumb it through
	contentType := contentTypeBytes
	type ContentType interface{ ContentType() string }
	if response, ok := response.(ContentType); ok {
		contentType = response.ContentType()
	}

	if err := invoke.success(response, contentType); err != nil {
		return fmt.Errorf("unexpected error occurred when sending the function functionResponse to the API: %v", err)
	}

	return nil
}