@RestController
@RequestMapping("/api/ssafast")
public class SsafastController {
    @PostMapping("")
    ResponseEntity<?> executeOverload(@RequestBody HashMap<String, String> map) {
        System.out.println(map.get("verification"));
        return new ResponseEntity<>("success", HttpStatus.OK);
    }
}

from django.http import HttpResponse
from django.views import View

class Ssafast(View):
    def post(self, request, *args, **kwargs):
        message = request.POST.get('verification', '')
        if message == '':
            return HttpResponse('fail')
        print(message)
        return HttpResponse('success')

from flask import Flask, request

app = Flask(__name__)

@app.route('/api/ssafast', methods=['POST'])
def receive_message():
    json_data = request.get_json()
    verification = json_data.get('verification')
    if not verification:
        return 'fail'
    print(verification)
    return 'success'