Cartesia TypeScript Library
The Cartesia TypeScript library provides convenient access to the Cartesia API from TypeScript.
Installation
npm i -s @cartesia/cartesia-js
Reference
A full reference for this library is available here.
Usage
Instantiation
Instantiate and use the client with the following:
import { CartesiaClient } from "@cartesia/cartesia-js";
const client = new CartesiaClient({ apiKey: "YOUR_API_KEY_HEADER" });
await client.tts.bytes({
modelId: "sonic-english",
transcript: "Hello, world!",
voice: {
mode: "id",
id: "694f9389-aac1-45b6-b726-9d9369183238",
},
language: "en",
outputFormat: {
container: "raw",
sampleRate: 44100,
encoding: "pcm_f32le",
},
});
TTS over WebSocket
import { CartesiaClient } from "@cartesia/cartesia-js";
const cartesia = new CartesiaClient({
apiKey: "your-api-key",
});
const websocket = cartesia.tts.websocket({
container: "raw",
encoding: "pcm_f32le",
sampleRate: 44100,
});
try {
await websocket.connect();
} catch (error) {
console.error(`Failed to connect to Cartesia: ${error}`);
}
const response = await websocket.send({
modelId: "sonic-english",
voice: {
mode: "id",
id: "a0e99841-438c-4a64-b679-ae501e7d6091",
},
transcript: "Hello, world!",
});
response.on("message", (message) => {
console.log("Received message:", message);
});
for await (const message of response.events("message")) {
console.log("Received message:", message);
}
Input Streaming with Contexts
const contextOptions = {
contextId: "my-context",
modelId: "sonic-english",
voice: {
mode: "id",
id: "a0e99841-438c-4a64-b679-ae501e7d6091",
},
};
const response = await websocket.send({
...contextOptions,
transcript: "Hello, world!",
});
await websocket.continue({
...contextOptions,
transcript: " How are you today?",
});
See the input streaming docs for more information.
Playing audio in the browser
(The WebPlayer
class only supports playing audio in the browser and the raw PCM format with fp32le encoding.)
import { WebPlayer } from "@cartesia/cartesia-js";
console.log("Playing stream...");
const player = new WebPlayer();
await player.play(response.source);
console.log("Done playing.");
Request And Response Types
The SDK exports all request and response types as TypeScript interfaces. Simply import them with the
following namespace:
import { Cartesia } from "@cartesia/cartesia-js";
const request: Cartesia.VoiceChangerBytesRequest = {
...
};
Exception Handling
When the API returns a non-success status code (4xx or 5xx response), a subclass of the following error
will be thrown.
import { CartesiaError } from "@cartesia/cartesia-js";
try {
await client.tts.bytes(...);
} catch (err) {
if (err instanceof CartesiaError) {
console.log(err.statusCode);
console.log(err.message);
console.log(err.body);
}
}
Advanced
Retries
The SDK is instrumented with automatic retries with exponential backoff. A request will be retried as long
as the request is deemed retriable and the number of retry attempts has not grown larger than the configured
retry limit (default: 2).
A request is deemed retriable when any of the following HTTP status codes is returned:
- 408 (Timeout)
- 429 (Too Many Requests)
- 5XX (Internal Server Errors)
Use the maxRetries
request option to configure this behavior.
const response = await client.tts.bytes(..., {
maxRetries: 0
});
Timeouts
The SDK defaults to a 60 second timeout. Use the timeoutInSeconds
option to configure this behavior.
const response = await client.tts.bytes(..., {
timeoutInSeconds: 30
});
Aborting Requests
The SDK allows users to abort requests at any point by passing in an abort signal.
const controller = new AbortController();
const response = await client.tts.bytes(..., {
abortSignal: controller.signal
});
controller.abort();
Runtime Compatibility
The SDK defaults to node-fetch
but will use the global fetch client if present. The SDK works in the following
runtimes:
- Node.js 18+
- Vercel
- Cloudflare Workers
- Deno v1.25+
- Bun 1.0+
- React Native
Customizing Fetch Client
The SDK provides a way for your to customize the underlying HTTP client / Fetch function. If you're running in an
unsupported environment, this provides a way for you to break glass and ensure the SDK works.
import { CartesiaClient } from "@cartesia/cartesia-js";
const client = new CartesiaClient({
...
fetcher:
});
Contributing
While we value open-source contributions to this SDK, this library is generated programmatically.
Additions made directly to this library would have to be moved over to our generation code,
otherwise they would be overwritten upon the next generated release. Feel free to open a PR as
a proof of concept, but know that we will not be able to merge it as-is. We suggest opening
an issue first to discuss with us!
On the other hand, contributions to the README are always very welcome!