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-rw-r--r--middleware.go72
1 files changed, 72 insertions, 0 deletions
diff --git a/middleware.go b/middleware.go
new file mode 100644
index 0000000..a759627
--- /dev/null
+++ b/middleware.go
@@ -0,0 +1,72 @@
+package httppb
+
+// http middleware example. probably not interesting since we only pass protobufs
+// middleware concepts might, or might not be useful here
+
+/*
+// Define a key type to avoid context key collisions.
+type contextKey string
+
+const bufferedBodyKey = contextKey("bufferedBody")
+
+// bufferBodyMiddleware reads the request body and replaces it with a new reader,
+// allowing it to be read multiple times. The original body is stored in the request context.
+func bufferBodyMiddleware(next http.Handler) http.Handler {
+ return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+ // Only buffer if there's a body to read.
+ if r.Body == nil || r.ContentLength == 0 {
+ next.ServeHTTP(w, r)
+ return
+ }
+
+ bodyBytes, err := ioutil.ReadAll(r.Body)
+ if err != nil {
+ log.Printf("Error reading body in middleware: %v\n", err)
+ return
+ }
+ defer r.Body.Close()
+
+ // Store the buffered body in the context for downstream handlers.
+ ctx := context.WithValue(r.Context(), bufferedBodyKey, bodyBytes)
+
+ // Replace the original body with a new reader on the buffered bytes.
+ // This allows subsequent handlers to read the body again.
+ r.Body = ioutil.NopCloser(bytes.NewReader(bodyBytes))
+
+ // Call the next handler in the chain with the modified request.
+ next.ServeHTTP(w, r.WithContext(ctx))
+ })
+}
+
+// okHandler is the final handler. It can now safely access the body from the context,
+// knowing that other middleware might have also read it.
+func okHandler(w http.ResponseWriter, r *http.Request) {
+ // For demonstration, we can try reading the body directly here too.
+ // The middleware ensures this is a fresh stream of the buffered data.
+ bodyFromStream, err := ioutil.ReadAll(r.Body)
+ if err != nil {
+ log.Printf("Error reading body in handler: %v", err)
+ http.Error(w, "Internal Server Error", http.StatusInternalServerError)
+ return
+ }
+
+ log.Printf("Handler read %d bytes from the request body stream.", len(bodyFromStream))
+
+ // We can also retrieve the body from the context if needed.
+ bodyFromContext, ok := r.Context().Value(bufferedBodyKey).([]byte)
+ if !ok {
+ log.Println("Could not retrieve buffered body from context.")
+ http.Error(w, "Internal Server Error", http.StatusInternalServerError)
+ return
+ }
+
+ log.Printf("Handler retrieved %d bytes from context.", len(bodyFromContext))
+
+ // Prove they are the same.
+ if !bytes.Equal(bodyFromStream, bodyFromContext) {
+ log.Println("FATAL: Body from stream and context do not match!")
+ }
+
+ fmt.Fprintf(w, "Successfully read body of %d bytes.\n", len(bodyFromContext))
+}
+*/