Diffio JS SDK

The Diffio JS SDK helps you call the Diffio API from Node. This version covers project creation, upload, generation, progress checks, and download URLs.

Install

npm install diffio

For local development:

cd diffio-js
npm install

Configuration

Set the API key with DIFFIO_API_KEY. If you need to set the base URL explicitly, use the production endpoint with DIFFIO_API_BASE_URL.

export DIFFIO_API_KEY="diffio_live_..."
export DIFFIO_API_BASE_URL="https://api.diffio.ai/v1"

Request options

Use request options to override headers, timeouts, retries, or the API key per request.

import { DiffioClient } from "diffio";

const client = new DiffioClient({ apiKey: "diffio_live_..." });
const projects = await client.listProjects({
  requestOptions: {
    headers: { "X-Debug": "1" },
    timeoutInSeconds: 30,
    maxRetries: 2,
    retryBackoff: 0.5
  }
});

Create a project and generation

createProject uploads the file and returns the project metadata.

import { DiffioClient } from "diffio";

const client = new DiffioClient({ apiKey: "diffio_live_..." });
const filePath = "sample.wav";

const project = await client.createProject({
  filePath
});

const generation = await client.createGeneration({
  apiProjectId: project.apiProjectId,
  model: "diffio-3.5",
  sampling: { steps: 12, guidance: 1.5 },
  idempotencyKey: "restore-sample-001"
});

console.log(generation.generationId, generation.idempotentReplay ?? false);

Reuse the same idempotencyKey when retrying generation creation for a project. The API then returns the existing generation with idempotentReplay: true instead of creating another generation.

Generation creation automatically retries only when you supply a nonblank idempotencyKey, reusing the same key and request body for every attempt. Without a key, generation creation is attempted once, including on network errors, even if client or request options enable retries. Other requests retain their configured retry policy. Reuse your original key and request body when manually retrying after an uncertain response.

waitForGeneration and generations.waitForComplete wait for the overall status to become complete. Individual stages reaching 100% or complete do not end polling while video publication or usage settlement is still pending. For Diffio 2.0, complete means restored media is ready; transcription can still be pending, become available later, or finish as unavailable. Read progress.transcription?.status independently. Older responses omit transcription; absence does not establish availability. Unavailable transcription does not fail completed Diffio 2.0 media. Diffio 3.5 requires its transcript before restoration can complete.

Audio isolation helper

import { DiffioClient } from "diffio";

const client = new DiffioClient({ apiKey: "diffio_live_..." });
const result = await client.audioIsolation.isolate({
  filePath: "sample.wav",
  model: "diffio-3.5",
  sampling: { steps: 12, guidance: 1.5 },
  idempotencyKey: "restore-sample-001"
});

console.log(result.generation.generationId);

The isolation helpers create a new project before creating its generation. Their idempotencyKey protects retries of that generation request; it does not deduplicate a separate helper call or upload.

Restore audio in one call

This helper runs the full flow and returns the downloaded bytes plus a metadata object.

import fs from "node:fs";
import { DiffioClient } from "diffio";

const client = new DiffioClient({ apiKey: "diffio_live_..." });
const [audioBytes, info] = await client.restoreAudio({
  filePath: "sample.wav",
  model: "diffio-3.5",
  sampling: { steps: 12, guidance: 1.5 },
  idempotencyKey: "restore-sample-001",
  onProgress: (progress) => console.log(progress.status)
});

if (info.error) {
  console.log(info.error);
} else if (audioBytes) {
  fs.writeFileSync("restored.mp3", Buffer.from(audioBytes));
}

console.log(info.apiProjectId, info.generationId);

Generation progress

import { DiffioClient } from "diffio";

const client = new DiffioClient({ apiKey: "diffio_live_..." });
const progress = await client.generations.getProgress({
  generationId: "gen_123",
  apiProjectId: "proj_123"
});

console.log(progress.status);
console.log(progress.transcription?.status ?? "not reported");

Generation download

import { DiffioClient } from "diffio";

const client = new DiffioClient({ apiKey: "diffio_live_..." });
const download = await client.generations.getDownload({
  generationId: "gen_123",
  apiProjectId: "proj_123",
  downloadType: "audio"
});

console.log(download.downloadUrl);

Set downloadType to "transcript" to fetch the transcript JSON artifact when available. Pending transcripts raise DiffioApiError with statusCode === 409 and error code TRANSCRIPT_PENDING. Unavailable transcripts return 404 with TRANSCRIPT_UNAVAILABLE. The responseBody also includes transcription.status. Check the error code to distinguish these from other 409 or 404 errors.

import { DiffioApiError } from "diffio";

try {
  const transcript = await client.generations.getDownload({
    generationId: "gen_123",
    apiProjectId: "proj_123",
    downloadType: "transcript"
  });
  console.log(transcript.downloadUrl);
} catch (error) {
  if (!(error instanceof DiffioApiError)) throw error;
  const body = error.responseBody;
  const code = body && typeof body === "object" && "code" in body ? body.code : undefined;
  if (error.statusCode === 409 && code === "TRANSCRIPT_PENDING") {
    console.log("Transcript pending; check progress and retry later.");
  } else if (error.statusCode === 404 && code === "TRANSCRIPT_UNAVAILABLE") {
    console.log("Transcript unavailable; restored media remains available.");
  } else {
    throw error;
  }
}

restoreAudio with downloadType: "transcript" also attempts a transcript download after media completion. It does not wait for pending transcription. With the default raiseOnError: false, it returns [null, info] and preserves info.statusCode and info.responseBody; info.status can still be complete because media restoration succeeded. With raiseOnError: true, it throws DiffioApiError and attaches metadata as error.restoreInfo. Poll progress and retry the download explicitly for the same generation. Audio and video downloads proceed independently of transcription.

Account, keys, usage, and webhook configuration

Agent keys can manage account settings, scoped keys, usage, and webhook endpoints.

const settings = await client.account.getSettings();
const key = await client.apiKeys.create({
  label: "Backend worker",
  scopes: ["projects:read", "projects:write", "generations:read", "generations:write", "artifacts:read"]
});
const usage = await client.usage.summary({ apiKeyId: key.keyId });
const webhook = await client.webhooks.configure({
  mode: "live",
  url: "https://example.com/webhooks/diffio",
  eventTypes: ["generation.completed", "generation.failed"],
  apiKeyId: key.keyId
});

List projects

import { DiffioClient } from "diffio";

const client = new DiffioClient({ apiKey: "diffio_live_..." });
const projects = await client.projects.list();

for (const project of projects.projects) {
  console.log(project.apiProjectId, project.status);
}

List project generations

import { DiffioClient } from "diffio";

const client = new DiffioClient({ apiKey: "diffio_live_..." });
const generations = await client.projects.listGenerations({ apiProjectId: "proj_123" });

for (const generation of generations.generations) {
  console.log(generation.generationId, generation.status);
}

Send a test webhook event

import { DiffioClient } from "diffio";

const client = new DiffioClient({ apiKey: "diffio_live_..." });
const event = await client.webhooks.sendTestEvent({
  eventType: "generation.completed",
  mode: "live",
  samplePayload: { apiProjectId: "proj_123" }
});

console.log(event.svixMessageId);

Verify webhook signatures

Use the raw request body (not parsed JSON) plus the svix-* headers and your webhook signing secret.

Verified events expose the same optional event.transcription object as generation progress. A Diffio 2.0 generation.completed event can report pending or unavailable transcription. Later transcript publication does not emit another completion event; poll progress when you need to follow a pending transcript. Older events can omit transcription.

import express from "express";
import { DiffioClient } from "diffio";

const app = express();
const client = new DiffioClient({ apiKey: process.env.DIFFIO_API_KEY });

app.post("/webhooks/diffio", express.raw({ type: "application/json" }), (req, res) => {
  const payload = req.body;
  const headers = {
    "svix-id": req.header("svix-id"),
    "svix-timestamp": req.header("svix-timestamp"),
    "svix-signature": req.header("svix-signature")
  };

  try {
    const event = client.webhooks.verifySignature({
      payload,
      headers,
      secret: process.env.DIFFIO_WEBHOOK_SECRET
    });
    console.log("Webhook received", event.eventType);
    res.status(200).send("ok");
  } catch (err) {
    res.status(400).send("Invalid signature");
  }
});

Runtime compatibility

Use Node 18 or later so fetch is available without extra packages. Examples use ES modules. Save files with a .mjs extension or set "type": "module" in your package.json.

Tests

cd diffio-js
npm run build