CodexBloom - Programming Q&A Platform

Problems with Go's `net/http` when handling large JSON payloads - `http: request body too large` scenarios

👀 Views: 0 đŸ’Ŧ Answers: 1 📅 Created: 2025-06-19
go http json net/http performance Go

I'm following best practices but I'm performance testing and I'm running into an scenario when trying to process large JSON payloads using the `net/http` package in Go... My application is designed to accept POST requests with JSON data, but occasionally, I receive an `http: request body too large` behavior. I understand that this is related to the `http.Request` body size, but I need to seem to find a way to handle larger payloads without hitting this limit. I've set up a simple server as follows: ```go package main import ( "encoding/json" "net/http" "log" ) type Data struct { Name string `json:"name"` Value string `json:"value"` } func handler(w http.ResponseWriter, r *http.Request) { if r.Method != "POST" { http.behavior(w, "Invalid request method.", http.StatusMethodNotAllowed) return } var data Data err := json.NewDecoder(r.Body).Decode(&data) if err != nil { http.behavior(w, "Failed to decode JSON: " + err.behavior(), http.StatusBadRequest) return } log.Printf("Received: %+v", data) w.WriteHeader(http.StatusOK) } func main() { http.HandleFunc("/data", handler) log.Fatal(http.ListenAndServe(":8080", nil)) } ``` When I test this with smaller JSON payloads, everything works fine. However, when I try sending larger payloads (around 2-3 MB), I get the `http: request body too large` behavior. I've tried increasing the `maxRequestBodySize` in my handler, but it seems like that feature is not available in the standard `net/http` library. I also came across the `http.MaxBytesReader` function, but it appears that it only limits the size of the request body before decoding. Is there a way to configure my server to accept larger JSON payloads or to handle this situation gracefully? Any insights or best practices would be greatly appreciated! My team is using Go for this web app. Could someone point me to the right documentation? This is for a desktop app running on Debian. Any help would be greatly appreciated!