SMTP

502 Command Not Implemented 응답 모의 테스트

The command is recognized by the SMTP specification but is not implemented on this server. The server understands the command but has chosen not to support it.

전체 레퍼런스 보기 →

1 HTTP 응답

HTTP 응답
HTTP/1.1 502 Command Not Implemented
Content-Type: application/json
Date: Tue, 25 Feb 2026 12:00:00 GMT
Content-Length: 60

{
  "error": "bad_gateway",
  "message": "Upstream server error"
}

2 curl로 테스트하기

terminal
curl -i https://httpbin.org/status/502

3 프레임워크에서 502 Command Not Implemented 반환하기

django
from django.http import JsonResponse


def my_view(request):
    return JsonResponse(
        {"error": "bad_gateway", "message": "Upstream server error"},
        status=502,
    )
flask
from flask import Flask, jsonify

app = Flask(__name__)


@app.route("/endpoint")
def my_endpoint():
    return jsonify({"error": "bad_gateway", "message": "Upstream server error"}), 502
fastapi
from fastapi import FastAPI
from fastapi.responses import JSONResponse

app = FastAPI()


@app.get("/endpoint")
def my_endpoint():
    return JSONResponse(
        content={"error": "bad_gateway", "message": "Upstream server error"},
        status_code=502,
    )
express.js
// Express.js
app.get('/endpoint', (req, res) => {
  res.status(502).json({"error": "bad_gateway", "message": "Upstream server error"});
});
spring boot
import org.springframework.http.ResponseEntity;
import org.springframework.web.bind.annotation.*;
import java.util.Map;

@RestController
public class MyController {

    @GetMapping("/endpoint")
    public ResponseEntity<Map<String, Object>> myEndpoint() {
        return ResponseEntity
            .status(502)
            .body(Map.of("error", "command_not_implemented",
                         "message", "Command Not Implemented"));
    }
}
go net/http
package main

import (
    "encoding/json"
    "net/http"
)

func myHandler(w http.ResponseWriter, r *http.Request) {
    w.Header().Set("Content-Type", "application/json")
    w.WriteHeader(502)
    json.NewEncoder(w).Encode(map[string]string{
        "error":   "command_not_implemented",
        "message": "Command Not Implemented",
    })
}
ruby on rails
class MyController < ApplicationController
  def my_action
    render json: {"error": "bad_gateway", "message": "Upstream server error"},
           status: :command_not_implemented
  end
end
asp.net core
// ASP.NET Core Minimal API
app.MapGet("/endpoint", () =>
    Results.Json(
        new { error = "command_not_implemented", message = "Command Not Implemented" },
        statusCode: 502
    )
);

더 많은 SMTP 모의 응답 페이지