SMTP

501 Syntax Error in Parameters 응답 모의 테스트

The command was recognized but the parameters or arguments are syntactically invalid. The server understood what you wanted to do but could not parse the details.

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1 HTTP 응답

HTTP 응답
HTTP/1.1 501 Syntax Error in Parameters
Content-Type: application/json
Date: Tue, 25 Feb 2026 12:00:00 GMT
Content-Length: 66

{
  "error": "server_error",
  "message": "Syntax Error in Parameters"
}

2 curl로 테스트하기

terminal
curl -i https://httpbin.org/status/501

3 프레임워크에서 501 Syntax Error in Parameters 반환하기

django
from django.http import JsonResponse


def my_view(request):
    return JsonResponse(
        {"error": "server_error", "message": "Syntax Error in Parameters"},
        status=501,
    )
flask
from flask import Flask, jsonify

app = Flask(__name__)


@app.route("/endpoint")
def my_endpoint():
    return jsonify({"error": "server_error", "message": "Syntax Error in Parameters"}), 501
fastapi
from fastapi import FastAPI
from fastapi.responses import JSONResponse

app = FastAPI()


@app.get("/endpoint")
def my_endpoint():
    return JSONResponse(
        content={"error": "server_error", "message": "Syntax Error in Parameters"},
        status_code=501,
    )
express.js
// Express.js
app.get('/endpoint', (req, res) => {
  res.status(501).json({"error": "server_error", "message": "Syntax Error in Parameters"});
});
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(501)
            .body(Map.of("error", "syntax_error_in_parameters",
                         "message", "Syntax Error in Parameters"));
    }
}
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(501)
    json.NewEncoder(w).Encode(map[string]string{
        "error":   "syntax_error_in_parameters",
        "message": "Syntax Error in Parameters",
    })
}
ruby on rails
class MyController < ApplicationController
  def my_action
    render json: {"error": "server_error", "message": "Syntax Error in Parameters"},
           status: :syntax_error_in_parameters
  end
end
asp.net core
// ASP.NET Core Minimal API
app.MapGet("/endpoint", () =>
    Results.Json(
        new { error = "syntax_error_in_parameters", message = "Syntax Error in Parameters" },
        statusCode: 501
    )
);

더 많은 SMTP 모의 응답 페이지