Server SDK

HTTP & WebSocket API

Raw HTTP endpoints for managing P2P calls and rooms. All endpoints here accept a secret key (rad_sk_...) and must only be called from your backend.

Overview

Calls with more than two participants use rooms. Create a room from your backend, mint one room token per participant, and each participant connects to the room signaling WebSocket. Audio and video are forwarded through a mediasoup worker.

Billing

Every second each participant is connected to a room is reported to Stripe as radist_sfu_participant_seconds. The 30-day total is visible on the project billing page.

HTTP API

P2P calls

POST /api/v1/projects/:projectId/calls

Creates a call and auto-mints two participant tokens. Authenticated with Authorization: Bearer rad_sk_... and the project id path parameter.

TypeScript

const projectId = '<your project id>';

const response = await fetch(`https://radist.tech/api/v1/projects/${projectId}/calls`, {
  method: 'POST',
  headers: {
    Authorization: 'Bearer <your secret key>'
  }
});

const { callId, callTokens } = await response.json();
const [hostCallToken, guestCallToken] = callTokens;

Status	Response
200	{ "callId": "uuid", "callTokens": ["ct_...", "ct_..."] }
401	{ "error": "Missing bearer token." } or invalid project id/key
429	{ "error": "Connection limit reached." }

GET /api/v1/projects/:projectId/calls

Lists calls for the project. Query parameters: page (default 1) and limit (default 20, max 100).

TypeScript

const projectId = '<your project id>';

const response = await fetch(
  `https://radist.tech/api/v1/projects/${projectId}/calls?page=1&limit=20`,
  {
    headers: { Authorization: 'Bearer <your secret key>' }
  }
);

const page = await response.json();
// { calls: [{ callId, createdAt, tombstonedAt }], page, limit, total }

Status	Response
200	{ "calls": [...], "page": 1, "limit": 20, "total": 42 }
400	{ "error": "Invalid page query parameter." }
401	{ "error": "Missing bearer token." } or invalid project id/key

Call lifecycle

Each P2P call starts with two pending tokens from POST /api/v1/projects/:projectId/calls.
Additional tokens can be minted by the client with the public-key endpoint.
Pending tokens are consumed once and cleared after both peers are connected.
A call is tombstoned after all peers disconnect.

SFU rooms

POST /api/v1/projects/:projectId/rooms

Creates a room and auto-mints two room tokens. Authenticated with Authorization: Bearer rad_sk_... and the project id path parameter.

TypeScript

const projectId = '<your project id>';

const response = await fetch(
  `https://radist.tech/api/v1/projects/${projectId}/rooms`,
  {
    method: 'POST',
    headers: { Authorization: 'Bearer <your secret key>' }
  }
);

const { roomId, roomTokens } = await response.json();

POST /api/v1/projects/:projectId/rooms/:roomId/token

Mints an additional room token for an existing room. Authenticated with Authorization: Bearer rad_sk_....

TypeScript

const projectId = '<your project id>';

const response = await fetch(
  `https://radist.tech/api/v1/projects/${projectId}/rooms/${roomId}/token`,
  {
    method: 'POST',
    headers: { Authorization: 'Bearer <your secret key>' }
  }
);

const { roomToken } = await response.json();

SFU WebSocket signaling

Participants connect to the SFU signaling WebSocket directly using a public key and room token. See the Client SDK API reference for the full protocol.