chore: export config BE handler for transformer, and unstarted http test server

testhelper/docker/resource/transformer/transformer.go

@@ -8,7 +8,7 @@ import (
 
  "github.com/samber/lo"
 
- dockerTestHelper "github.com/rudderlabs/rudder-go-kit/testhelper/docker"
+ dockertesthelper "github.com/rudderlabs/rudder-go-kit/testhelper/docker"
 
  "github.com/ory/dockertest/v3"
  "github.com/ory/dockertest/v3/docker"
@@ -56,21 +56,29 @@ func (c *config) setBackendConfigURL(url string) {
 // })
 func WithUserTransformations(transformations map[string]string, cleaner resource.Cleaner) func(*config) {
  return func(conf *config) {
- backendConfigSvc := NewTestBackendConfigServer(transformations)
+ backendConfigSvc := newTestBackendConfigServer(transformations)
 
- conf.setBackendConfigURL(dockerTestHelper.ToInternalDockerHost(backendConfigSvc.URL))
+ conf.setBackendConfigURL(dockertesthelper.ToInternalDockerHost(backendConfigSvc.URL))
  conf.extraHosts = append(conf.extraHosts, "host.docker.internal:host-gateway")
  cleaner.Cleanup(func() {
  backendConfigSvc.Close()
  })
  }
 }
 
+// WithConnectionToHostEnabled lets transformer container connect with the host machine
+// i.e. transformer container will be able to access localhost of the host machine
+func WithConnectionToHostEnabled() func(*config) {
+ return func(conf *config) {
+ conf.extraHosts = append(conf.extraHosts, "host.docker.internal:host-gateway")
+ }
+}
+
 // WithConfigBackendURL lets transformer use custom backend config server for transformations
 // WithConfigBackendURL should not be used with WithUserTransformations option
 func WithConfigBackendURL(url string) func(*config) {
  return func(conf *config) {
- conf.setBackendConfigURL(url)
+ conf.setBackendConfigURL(dockertesthelper.ToInternalDockerHost(url))
  }
 }
 

testhelper/docker/resource/transformer/transformer_backend_config.go

@@ -14,10 +14,15 @@ const (
  versionIDKey = "versionId"
 )
 
-func NewTestBackendConfigServer(transformations map[string]string) *kithttptest.Server {
+func newTestBackendConfigServer(transformations map[string]string) *kithttptest.Server {
+ return kithttptest.NewServer(NewTransformerBackendConfigHandler(transformations))
+}
+
+// NewTransformerBackendConfigHandler returns http request handler to handle all backend config requests by transformer
+func NewTransformerBackendConfigHandler(transformations map[string]string) http.Handler {
  mux := http.NewServeMux()
  mux.HandleFunc(getByVersionIdEndPoint, getByVersionIdHandler(transformations))
- return kithttptest.NewServer(mux)
+ return mux
 }
 
 func getByVersionIdHandler(transformations map[string]string) func(http.ResponseWriter, *http.Request) {

testhelper/httptest/httptest.go

@@ -10,7 +10,7 @@ import (
 // NewServer starts a new httptest server that listens on all interfaces, contrary to the standard net/httptest.Server that listens only on localhost.
 // This is useful when you want to access the test http server from within a docker container.
 func NewServer(handler http.Handler) *Server {
- ts := newUnStartedServer(handler)
+ ts := NewUnStartedServer(handler)
  ts.start()
  return ts
 }
@@ -29,7 +29,7 @@ func (s *Server) start() {
  s.URL = fmt.Sprintf("http://%s:%s", "localhost", port)
 }
 
-func newUnStartedServer(handler http.Handler) *Server {
+func NewUnStartedServer(handler http.Handler) *Server {
  return &Server{&nethttptest.Server{
  Listener: newListener(),
  Config: &http.Server{Handler: handler},

testhelper/httptest/httptest_test.go

@@ -43,3 +43,37 @@ func TestServer(t *testing.T) {
  require.Equal(t, http.StatusOK, statusCode)
  require.Equal(t, "Hello, world!", string(body))
 }
+
+func TestUnStartedServer(t *testing.T) {
+ // create a server which is not started
+ httpUnStartedServer := kithttptest.NewUnStartedServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+ _, _ = w.Write([]byte("Hello, world!"))
+ }))
+
+ var (
+ body []byte
+ statusCode int
+ )
+ require.Never(t, func() bool {
+ resp, err := http.Get("http://" + httpUnStartedServer.Listener.Addr().String())
+ defer func() { httputil.CloseResponse(resp) }()
+ return err == nil
+ }, 5*time.Second, 10*time.Millisecond, "connected to an un-started server")
+
+ // start the server now
+ httpUnStartedServer.Start()
+ defer httpUnStartedServer.Close()
+
+ require.Eventually(t, func() bool {
+ resp, err := http.Get(httpUnStartedServer.URL)
+ defer func() { httputil.CloseResponse(resp) }()
+ if err == nil {
+ statusCode = resp.StatusCode
+ body, err = io.ReadAll(resp.Body)
+ }
+ return err == nil
+ }, 2*time.Second, 100*time.Millisecond, "failed to connect to server")
+
+ require.Equal(t, http.StatusOK, statusCode)
+ require.Equal(t, "Hello, world!", string(body))
+}