refactor(ls-api): extract shared LS↔RIE API types into internal/lsapi

InvokeRequest, LogResponse, and ErrorResponse were duplicated across
cmd/localstack and cmd/ls-api. Moving them to internal/lsapi/types.go
makes both packages use the same definitions and removes the duplication
flagged in the PR review.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

Author: joe4dev

cmd/localstack/custom_interop.go

@@ -18,6 +18,7 @@ import (
 	"github.com/aws/aws-lambda-runtime-interface-emulator/internal/lambda/interop"
 	"github.com/aws/aws-lambda-runtime-interface-emulator/internal/lambda/rapidcore"
 	"github.com/aws/aws-lambda-runtime-interface-emulator/internal/lambda/rapidcore/standalone"
+	"github.com/aws/aws-lambda-runtime-interface-emulator/internal/lsapi"
 	"github.com/go-chi/chi/v5"
 	log "github.com/sirupsen/logrus"
 )
@@ -51,7 +52,7 @@ func (l *LocalStackAdapter) SendStatus(status LocalStackStatus, payload []byte)
 }
 
 // SendLogs posts the captured invocation logs to LocalStack.
-func (l *LocalStackAdapter) SendLogs(invokeId string, logs LogResponse) error {
+func (l *LocalStackAdapter) SendLogs(invokeId string, logs lsapi.LogResponse) error {
 	serialized, err := json.Marshal(logs)
 	if err != nil {
 		return err
@@ -81,22 +82,6 @@ func (l *LocalStackAdapter) SendResult(invokeId string, body []byte, isError boo
 	return err
 }
 
-// The InvokeRequest is sent by LocalStack to trigger an invocation
-type InvokeRequest struct {
-	InvokeId           string `json:"invoke-id"`
-	InvokedFunctionArn string `json:"invoked-function-arn"`
-	Payload            string `json:"payload"`
-	TraceId            string `json:"trace-id"`
-}
-
-// The ErrorResponse is sent TO LocalStack when encountering an error
-type ErrorResponse struct {
-	ErrorMessage string   `json:"errorMessage"`
-	ErrorType    string   `json:"errorType,omitempty"`
-	RequestId    string   `json:"requestId,omitempty"`
-	StackTrace   []string `json:"stackTrace,omitempty"`
-}
-
 func NewCustomInteropServer(lsOpts *LsOpts, delegate interop.Server, logCollector *LogCollector) (server *CustomInteropServer) {
 	server = &CustomInteropServer{
 		delegate:         delegate.(*rapidcore.Server),
@@ -112,7 +97,7 @@ func NewCustomInteropServer(lsOpts *LsOpts, delegate interop.Server, logCollecto
 	go func() {
 		r := chi.NewRouter()
 		r.Post("/invoke", func(w http.ResponseWriter, r *http.Request) {
-			invokeR := InvokeRequest{}
+			invokeR := lsapi.InvokeRequest{}
 			bytess, err := io.ReadAll(r.Body)
 			if err != nil {
 				log.Error(err)
@@ -154,7 +139,7 @@ func NewCustomInteropServer(lsOpts *LsOpts, delegate interop.Server, logCollecto
 					case errors.Is(err, rapidcore.ErrInvokeTimeout):
 						log.Debugf("Got invoke timeout")
 						isErr = true
-						errorResponse := ErrorResponse{
+						errorResponse := lsapi.ErrorResponse{
 							ErrorMessage: fmt.Sprintf(
 								"%s %s Task timed out after %d.00 seconds",
 								time.Now().Format("2006-01-02T15:04:05Z"),

cmd/localstack/custom_interop_test.go

@@ -7,6 +7,7 @@ import (
 	"net/http/httptest"
 	"testing"
 
+	"github.com/aws/aws-lambda-runtime-interface-emulator/internal/lsapi"
 	"github.com/stretchr/testify/assert"
 	"github.com/stretchr/testify/require"
 )
@@ -28,7 +29,7 @@ func TestInvokeRequestContract(t *testing.T) {
 		"trace-id":             "Root=1-abc;Parent=def;Sampled=1"
 	}`
 
-	var req InvokeRequest
+	var req lsapi.InvokeRequest
 	require.NoError(t, json.Unmarshal([]byte(raw), &req))
 
 	assert.Equal(t, "abc-123", req.InvokeId)
@@ -42,7 +43,7 @@ func TestInvokeRequestContract(t *testing.T) {
 func TestLogResponseContract(t *testing.T) {
 	raw := `{"logs":"START RequestId: abc\nEND RequestId: abc\n"}`
 
-	var lr LogResponse
+	var lr lsapi.LogResponse
 	require.NoError(t, json.Unmarshal([]byte(raw), &lr))
 
 	assert.Equal(t, "START RequestId: abc\nEND RequestId: abc\n", lr.Logs)
@@ -84,7 +85,7 @@ func TestSendStatus_ErrorSendsToCorrectPath(t *testing.T) {
 
 func TestSendLogs_SendsJSONWithLogsKey(t *testing.T) {
 	var capturedPath string
-	var capturedBody LogResponse
+	var capturedBody lsapi.LogResponse
 	srv := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
 		capturedPath = r.URL.Path
 		body, _ := io.ReadAll(r.Body)
@@ -94,7 +95,7 @@ func TestSendLogs_SendsJSONWithLogsKey(t *testing.T) {
 	defer srv.Close()
 
 	adapter := &LocalStackAdapter{UpstreamEndpoint: srv.URL}
-	logs := LogResponse{Logs: "START RequestId: invoke-1\nEND RequestId: invoke-1\n"}
+	logs := lsapi.LogResponse{Logs: "START RequestId: invoke-1\nEND RequestId: invoke-1\n"}
 	require.NoError(t, adapter.SendLogs("invoke-1", logs))
 
 	assert.Equal(t, "/invocations/invoke-1/logs", capturedPath)

cmd/localstack/logs.go

@@ -3,11 +3,9 @@ package main
 import (
 	"strings"
 	"sync"
-)
 
-type LogResponse struct {
-	Logs string `json:"logs"`
-}
+	"github.com/aws/aws-lambda-runtime-interface-emulator/internal/lsapi"
+)
 
 type LogCollector struct {
 	mutex       *sync.Mutex
@@ -37,10 +35,10 @@ func (lc *LogCollector) reset() {
 	lc.RuntimeLogs = []string{}
 }
 
-func (lc *LogCollector) getLogs() LogResponse {
+func (lc *LogCollector) getLogs() lsapi.LogResponse {
 	lc.mutex.Lock()
 	defer lc.mutex.Unlock()
-	response := LogResponse{
+	response := lsapi.LogResponse{
 		Logs: strings.Join(lc.RuntimeLogs, ""),
 	}
 	lc.RuntimeLogs = []string{}

cmd/ls-api/main.go

@@ -5,11 +5,13 @@ import (
 	"bytes"
 	"encoding/json"
 	"fmt"
+	"io"
+	"net/http"
+
+	"github.com/aws/aws-lambda-runtime-interface-emulator/internal/lsapi"
 	"github.com/go-chi/chi"
 	"github.com/go-chi/chi/middleware"
 	log "github.com/sirupsen/logrus"
-	"io"
-	"net/http"
 )
 
 const apiPort = 9563
@@ -30,7 +32,7 @@ func main() {
 	router.Post("/status/{runtime_id}/{status}", statusHandler)
 
 	router.Get("/success", func(w http.ResponseWriter, r *http.Request) {
-		invokeRequest, _ := json.Marshal(InvokeRequest{InvokeId: uid, Payload: "{\"counter\":0}"})
+		invokeRequest, _ := json.Marshal(lsapi.InvokeRequest{InvokeId: uid, Payload: "{\"counter\":0}"})
 		_, err := http.Post(invokeUrl, "application/json", bytes.NewReader(invokeRequest))
 		if err != nil {
 			log.Error(err)
@@ -44,7 +46,7 @@ func main() {
 	})
 
 	router.Get("/fail", func(w http.ResponseWriter, r *http.Request) {
-		invokeRequest, _ := json.Marshal(InvokeRequest{InvokeId: uid, Payload: "{\"counter\":0, \"fail\": \"yes\"}"})
+		invokeRequest, _ := json.Marshal(lsapi.InvokeRequest{InvokeId: uid, Payload: "{\"counter\":0, \"fail\": \"yes\"}"})
 		_, err := http.Post(invokeUrl, "application/json", bytes.NewReader(invokeRequest))
 		if err != nil {
 			log.Error(err)
@@ -67,7 +69,7 @@ func main() {
 func invokeLogsHandler(w http.ResponseWriter, r *http.Request) {
 	invokeId := chi.URLParam(r, "invoke_id")
 	log.Println(invokeId)
-	var logResponse LogResponse
+	var logResponse lsapi.LogResponse
 	if err := json.NewDecoder(r.Body).Decode(&logResponse); err != nil {
 		log.Error("invalid logs payload: ", err)
 	} else {
@@ -76,26 +78,13 @@ func invokeLogsHandler(w http.ResponseWriter, r *http.Request) {
 	w.WriteHeader(http.StatusAccepted)
 }
 
-// InvokeRequest is sent by LocalStack to trigger an invocation.
-type InvokeRequest struct {
-	InvokeId           string `json:"invoke-id"`
-	InvokedFunctionArn string `json:"invoked-function-arn"`
-	Payload            string `json:"payload"`
-	TraceId            string `json:"trace-id"`
-}
-
-// LogResponse is sent by the runtime to report logs for a completed invocation.
-type LogResponse struct {
-	Logs string `json:"logs"`
-}
-
 func statusHandler(w http.ResponseWriter, r *http.Request) {
 	runtime_id := chi.URLParam(r, "runtime_id")
 	status := chi.URLParam(r, "status")
 	log.Println(runtime_id + " + " + status)
 	if status == "ready" {
 		go func() {
-			invokeRequest, _ := json.Marshal(InvokeRequest{InvokeId: "12345", Payload: "{\"counter\":0}"})
+			invokeRequest, _ := json.Marshal(lsapi.InvokeRequest{InvokeId: "12345", Payload: "{\"counter\":0}"})
 			_, err := http.Post(invokeUrl, "application/json", bytes.NewReader(invokeRequest))
 			if err != nil {
 				log.Error(err)

cmd/ls-api/main_test.go

@@ -8,6 +8,7 @@ import (
 	"testing"
 	"time"
 
+	"github.com/aws/aws-lambda-runtime-interface-emulator/internal/lsapi"
 	"github.com/go-chi/chi"
 	"github.com/stretchr/testify/assert"
 	"github.com/stretchr/testify/require"
@@ -71,7 +72,7 @@ func TestInvocationLogsReturns202(t *testing.T) {
 	srv := httptest.NewServer(newTestRouter())
 	defer srv.Close()
 
-	logPayload, err := json.Marshal(LogResponse{
+	logPayload, err := json.Marshal(lsapi.LogResponse{
 		Logs: "START RequestId: " + testInvokeID + " Version: $LATEST\nEND RequestId: " + testInvokeID + "\n",
 	})
 	require.NoError(t, err)
@@ -91,9 +92,9 @@ func TestInvocationLogsReturns202(t *testing.T) {
 //   - returns 202 Accepted (matching LocalStack executor_endpoint.py status_ready)
 //   - asynchronously sends a POST to the invoke endpoint with a valid InvokeRequest body
 func TestStatusReadyReturns202AndTriggersInvoke(t *testing.T) {
-	invokeCh := make(chan InvokeRequest, 1)
+	invokeCh := make(chan lsapi.InvokeRequest, 1)
 	captureServer := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
-		var req InvokeRequest
+		var req lsapi.InvokeRequest
 		require.NoError(t, json.NewDecoder(r.Body).Decode(&req))
 		invokeCh <- req
 		w.WriteHeader(http.StatusOK)

internal/lsapi/types.go

@@ -0,0 +1,22 @@
+package lsapi
+
+// InvokeRequest is sent by LocalStack to trigger an invocation.
+type InvokeRequest struct {
+	InvokeId           string `json:"invoke-id"`
+	InvokedFunctionArn string `json:"invoked-function-arn"`
+	Payload            string `json:"payload"`
+	TraceId            string `json:"trace-id"`
+}
+
+// LogResponse is sent by the runtime to report logs for a completed invocation.
+type LogResponse struct {
+	Logs string `json:"logs"`
+}
+
+// ErrorResponse is sent to LocalStack when encountering an error.
+type ErrorResponse struct {
+	ErrorMessage string   `json:"errorMessage"`
+	ErrorType    string   `json:"errorType,omitempty"`
+	RequestId    string   `json:"requestId,omitempty"`
+	StackTrace   []string `json:"stackTrace,omitempty"`
+}