SIP
Mock 183 Session Progress Response
Used to convey information about the progress of the call that is not otherwise classified. Often carries early media (ringback tones, announcements) via SDP.
View full reference →1 HTTP Response
HTTP/1.1 183 Session Progress Content-Type: application/json Date: Tue, 25 Feb 2026 12:00:00 GMT
2 Test with curl
curl -i https://httpbin.org/status/183
3 Return 183 Session Progress in Your Framework
django
from django.http import HttpResponse
def my_view(request):
return HttpResponse(status=183) # Session Progress
flask
from flask import Flask
app = Flask(__name__)
@app.route("/endpoint")
def my_endpoint():
return "", 183 # Session Progress
fastapi
from fastapi import FastAPI
from fastapi.responses import Response
app = FastAPI()
@app.get("/endpoint")
def my_endpoint():
return Response(status_code=183) # Session Progress
express.js
// Express.js
app.get('/endpoint', (req, res) => {
res.sendStatus(183); // Session Progress
});
spring boot
import org.springframework.http.ResponseEntity;
import org.springframework.web.bind.annotation.*;
@RestController
public class MyController {
@GetMapping("/endpoint")
public ResponseEntity<Void> myEndpoint() {
return ResponseEntity
.status(183) // Session Progress
.build();
}
}
go net/http
package main
import "net/http"
func myHandler(w http.ResponseWriter, r *http.Request) {
w.WriteHeader(183) // Session Progress
}
ruby on rails
class MyController < ApplicationController
def my_action
head :session_progress
end
end
asp.net core
// ASP.NET Core Minimal API
app.MapGet("/endpoint", () =>
Results.StatusCode(183) // Session Progress
);