Writer TypeScript API Library

This library provides access to the Writer REST API from server-side TypeScript(>=4.9) or JavaScript.

The REST API documentation can be found on dev.writer.com. The full API of this library can be found in api.md.

It is generated with Stainless.

Installation

npm install writer-sdk

Requirements

You need a Writer API key to use this library.

Supported runtimes

• Web browsers (Up-to-date Chrome, Firefox, Safari, Edge, and more)
• Node.js 18 LTS or later (non-EOL) versions.
• Deno v1.28.0 or higher.
• Bun 1.0 or later.
• Cloudflare Workers.
• Vercel Edge Runtime.
• Jest 28 or greater with the "node" environment ("jsdom" is not supported at this time).
• Nitro v2.6 or greater.

React Native is not supported at this time.

If you are interested in other runtime environments, please open or upvote an issue on GitHub.

Authentication

To authenticate with the Writer API, set the WRITER_API_KEY environment variable.

$ export WRITER_API_KEY="my-api-key"

The Writer class automatically infers your API key from the WRITER_API_KEY environment variable.

import Writer from 'writer-sdk';

const client = new Writer();

You can also explicitly set the API key with the apiKey parameter:

import Writer from 'writer-sdk';

const client = new Writer({
  apiKey: 'my-api-key',
});

Never hard-code your API keys in source code or commit them to version control systems like GitHub. We recommend adding WRITER_API_KEY="My API Key" to your .env file so that your API Key is not stored in source control.

Usage

You can find the full API for this library in api.md.

import Writer from 'writer-sdk';

const client = new Writer();

async function main() {
  const chatCompletion = await client.chat.chat({
    messages: [{ content: 'Write a poem about Python', role: 'user' }],
    model: 'palmyra-x-004',
  });

  console.log(chatCompletion.choices[0].message.content);
}

main();

Streaming responses

We provide support for streaming responses using Server Sent Events (SSE).

import Writer from 'writer-sdk';

const client = new Writer();

const stream = await client.chat.chat({
  messages: [{ content: 'Write a poem about Python', role: 'user' }],
  model: 'palmyra-x-004',
  stream: true,
});
let outputText = "";
for await (const chunk of stream) {
    if (chunk.choices[0]?.delta?.content) {
        outputText += chunk.choices[0].delta.content;
    } else {
        continue;
    }
}
console.log(outputText);

If you need to cancel a stream, you can break from the loop or call stream.controller.abort().

Request and response types

This library includes TypeScript definitions for all request params and response fields. Import and use them like so:

import Writer from 'writer-sdk';

const client = new Writer();

async function main() {
  const params: Writer.ChatChatParams = {
    messages: [{ content: 'Write a poem about Python', role: 'user' }],
    model: 'palmyra-x-004',
  };
  const chatCompletion: Writer.ChatCompletion = await client.chat.chat(params);
}

main();

Documentation for each method, request parameter, and response field are available in docstrings and will appear on hover in most modern editors.

File uploads

Request parameters that correspond to file uploads can be passed in many different forms:

• File (or an object with the same structure)
• a fetch Response (or an object with the same structure)
• an fs.ReadStream
• the return value of our toFile helper

The Content-Type parameter is the MIME type of the file being uploaded. The file upload supports txt, doc, docx, ppt, pptx, jpg, png, eml, html, pdf, srt, csv, xls, and xlsx file extensions.

import fs from 'fs';
import Writer, { toFile } from 'writer-sdk';

const client = new Writer();

// If you have access to Node `fs` we recommend using `fs.createReadStream()`:
await client.files.upload({
  content: fs.createReadStream('/path/to/file.pdf'),
  'Content-Disposition': 'attachment; filename="example.pdf"',
  'Content-Type': 'application/pdf',
});

// If you have the web `File` API you can pass a `File` instance:
await client.files.upload({
  content: new File(['my bytes'], 'example.txt'),
  'Content-Disposition': 'attachment; filename="example.txt"',
  'Content-Type': 'text/plain',
});

// You can also pass a `fetch` `Response`:
await client.files.upload({
  content: await fetch('https://example.com/example.pdf'),
  'Content-Disposition': 'attachment; filename="example.pdf"',
  'Content-Type': 'application/pdf',
});

// Finally, if none of the above are convenient, you can use our `toFile` helper:
await client.files.upload({
  content: await toFile(Buffer.from('my bytes'), 'example.txt'),
  'Content-Disposition': 'attachment; filename="example.txt"',
  'Content-Type': 'text/plain',
});
await client.files.upload({
  content: await toFile(new Uint8Array([0, 1, 2]), 'example.txt'),
  'Content-Disposition': 'attachment; filename="example.txt"',
  'Content-Type': 'text/plain',
});

Error handling

When the library is unable to connect to the API (for example, due to a network connectivity problem or a firewall that doesn't allow the connection), or if the API returns a non-success status code (4xx or 5xx response), a subclass of APIError will be thrown.

If you are behind a firewall, you may need to configure it to allow connections to the Writer API at https://api.writer.com/v1.

async function main() {
  const chatCompletion = await client.chat
    .chat({ messages: [{ content: 'Write a poem about Python', role: 'user' }], model: 'palmyra-x-004' })
    .catch(async (err) => {
      if (err instanceof Writer.APIError) {
        console.log(err.status); // 400
        console.log(err.name); // BadRequestError
        console.log(err.headers); // {server: 'nginx', ...}
      } else {
        throw err;
      }
    });
}

main();

Error codes are as follows:

Status Code	Error Type
400	BadRequestError
401	AuthenticationError
403	PermissionDeniedError
404	NotFoundError
422	UnprocessableEntityError
429	RateLimitError
>=500	InternalServerError
N/A	APIConnectionError

Retries

The library automatically retries certain errors two times by default, with a short exponential backoff. Connection errors, 408 Request Timeout, 409 Conflict, 429 Rate Limit, and >=500 Internal errors are all retried by default.

You can use the maxRetries option to configure or disable this:

// Configure the default for all requests:
const client = new Writer({
  maxRetries: 0, // default is 2
});

// Or, configure per request:
await client.chat.chat({ messages: [{ content: 'Write a poem about Python', role: 'user' }], model: 'palmyra-x-004' }, {
  maxRetries: 5,
});

Timeouts

Requests time out after three minutes by default. You can configure this with a timeout option:

// Configure the default for all requests:
const client = new Writer({
  timeout: 20 * 1000, // 20 seconds (default is 3 minutes)
});

// Override per request:
await client.chat.chat({ messages: [{ content: 'Write a poem about Python', role: 'user' }], model: 'palmyra-x-004' }, {
  timeout: 5 * 1000,
});

On timeout, an APIConnectionTimeoutError is thrown.

Requests that time out will be retried twice by default.

Pagination

List methods in the Writer API are paginated. You can use the for await … of syntax to iterate through items across all pages:

async function fetchAllGraphs(params) {
  const allGraphs = [];
  // Automatically fetches more pages as needed.
  for await (const graph of client.graphs.list()) {
    allGraphs.push(graph);
  }
  return allGraphs;
}

Alternatively, you can request a single page at a time:

let page = await client.graphs.list();
for (const graph of page.data) {
  console.log(graph);
}

// Convenience methods are provided for manually paginating:
while (page.hasNextPage()) {
  page = await page.getNextPage();
  // ...
}

Advanced Usage

Accessing raw response data

When you use fetch() to make requests, you can access the raw Response through the .asResponse() method on the APIPromise type that all methods return.

You can also use the .withResponse() method to get the raw Response along with the parsed data.

const client = new Writer();

const response = await client.chat
  .chat({ messages: [{ content: 'Write a poem about Python', role: 'user' }], model: 'palmyra-x-004' })
  .asResponse();
console.log(response.headers.get('X-My-Header'));
console.log(response.statusText); // access the underlying Response object

const { data: chatCompletion, response: raw } = await client.chat
  .chat({ messages: [{ content: 'Write a poem about Python', role: 'user' }], model: 'palmyra-x-004' })
  .withResponse();
console.log(raw.headers.get('X-My-Header'));
console.log(chatCompletion.id);

Logging

Important

All log messages are intended for debugging only. The format and content of log messages may change between releases.

Log levels

The log level can be configured in two ways:

1. Via the WRITER_LOG environment variable
2. Using the logLevel client option (overrides the environment variable if set)

import Writer from 'writer-sdk';

const client = new Writer({
  logLevel: 'debug', // Show all log messages
});

Available log levels, from most to least verbose:

• 'debug' - Show debug messages, info, warnings, and errors
• 'info' - Show info messages, warnings, and errors
• 'warn' - Show warnings and errors (default)
• 'error' - Show only errors
• 'off' - Disable all logging

At the 'debug' level, all HTTP requests and responses are logged, including headers and bodies. Some authentication-related headers are redacted, but sensitive data in request and response bodies may still be visible.

Custom logger

By default, this library logs to globalThis.console. You can also provide a custom logger. Most logging libraries are supported, including pino, winston, bunyan, consola, signale, and @std/log. If your logger doesn't work, please open an issue.

When providing a custom logger, the logLevel option still controls which messages are emitted, messages below the configured level will not be sent to your logger.

import Writer from 'writer-sdk';
import pino from 'pino';

const logger = pino();

const client = new Writer({
  logger: logger.child({ name: 'Writer' }),
  logLevel: 'debug', // Send all messages to pino, allowing it to filter
});

Making custom/undocumented requests

This library is typed for convenient access to the documented API. If you need to access undocumented endpoints, parameters, or response properties, you can still use the library.

Undocumented endpoints

To make requests to undocumented endpoints, use client.get, client.post, and other HTTP verbs. Options on the client, such as retries, will be respected when making these requests.

await client.post('/some/path', {
  body: { some_prop: 'foo' },
  query: { some_query_arg: 'bar' },
});

Undocumented request parameters

To make requests using undocumented parameters, you may use // @ts-expect-error on the undocumented parameter. This library doesn't validate at runtime that the request matches the type, so any extra values you send will be sent as-is.

client.foo.create({
  foo: 'my_param',
  bar: 12,
  // @ts-expect-error baz is not yet public
  baz: 'undocumented option',
});

For requests with the GET verb, any extra parameters will be in the query. All other requests will send the extra parameter in the body of the request.

If you want to explicitly send an extra argument, you can do so with the query, body, and headers request options.

Undocumented response properties

To access undocumented response properties, access the response object with // @ts-expect-error on the response object, or cast the response object to the requisite type. Like the request parameters, we do not validate or strip extra properties from the response from the API.

Customizing the fetch client

By default, this library expects a global fetch function is defined.

If you want to use a different fetch function, you can either polyfill the global:

import fetch from 'my-fetch';

globalThis.fetch = fetch;

Or pass it to the client:

import Writer from 'writer-sdk';
import fetch from 'my-fetch';

const client = new Writer({ fetch });

Fetch options

If you want to set custom fetch options without overriding the fetch function, you can provide a fetchOptions object when instantiating the client or making a request. (Request-specific options override client options.)

import Writer from 'writer-sdk';

const client = new Writer({
  fetchOptions: {
    // `RequestInit` options
  },
});

Configuring proxies

To modify proxy behavior, you can provide custom fetchOptions that add runtime-specific proxy options to requests:

Node ^[docs]

import Writer from 'writer-sdk';
import * as undici from 'undici';

const proxyAgent = new undici.ProxyAgent('http://localhost:8888');
const client = new Writer({
  fetchOptions: {
    dispatcher: proxyAgent,
  },
});

Bun ^[docs]

import Writer from 'writer-sdk';

const client = new Writer({
  fetchOptions: {
    proxy: 'http://localhost:8888',
  },
});

Deno ^[docs]

import Writer from 'npm:writer-sdk';

const httpClient = Deno.createHttpClient({ proxy: { url: 'http://localhost:8888' } });
const client = new Writer({
  fetchOptions: {
    client: httpClient,
  },
});

Frequently Asked Questions

Semantic versioning

This package generally follows SemVer conventions, though certain backwards-incompatible changes may be released as minor versions:

1. Changes that only affect static types, without breaking runtime behavior.
2. Changes to library internals which are technically public but not intended or documented for external use. (Please open a GitHub issue to let us know if you are relying on such internals.)
3. Changes that we do not expect to impact the vast majority of users in practice.

We take backwards compatibility seriously and work hard to ensure you can rely on a smooth upgrade experience.

Feedback

We welcome feedback! Please open an issue with questions, bugs, or suggestions.