Modern Treasury Node API Library

This library provides convenient access to the Modern Treasury Node REST API from server-side TypeScript or JavaScript.

The API documentation can be found here.

Installation

npm install --save modern-treasury
# or
yarn add modern-treasury

Usage

import ModernTreasury from 'modern-treasury';

const modernTreasury = new ModernTreasury({
  apiKey: 'my api key', // defaults to process.env["MODERN_TREASURY_API_KEY"]
  organizationId: 'my-organization-ID',
});

async function main() {
  const externalAccount = await modernTreasury.externalAccounts.create({
    counterparty_id: '9eba513a-53fd-4d6d-ad52-ccce122ab92a',
    name: 'my bank',
  });

  console.log(externalAccount.id);
}

main();

Request & Response types

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

import ModernTreasury from 'modern-treasury';

const modernTreasury = new ModernTreasury({
  apiKey: 'my api key', // defaults to process.env["MODERN_TREASURY_API_KEY"]
  organizationId: 'my-organization-ID',
});

async function main() {
  const params: ModernTreasury.ExternalAccountCreateParams = {
    counterparty_id: '9eba513a-53fd-4d6d-ad52-ccce122ab92a',
    name: 'my bank',
  };
  const externalAccount: ModernTreasury.ExternalAccount = await modernTreasury.externalAccounts.create(
    params,
  );
}

main();

Documentation for each method, request param, 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

import fs from 'fs';
import fetch from 'node-fetch';
import ModernTreasury, { toFile } from 'modern-treasury';

const modernTreasury = new ModernTreasury();

// If you have access to Node `fs` we recommend using `fs.createReadStream()`:
await modernTreasury.documents.create({
  documentable_id: '24c6b7a3-02...',
  documentable_type: 'counterparties',
  file: fs.createReadStream('my/file.txt'),
});

// Or if you have the web `File` API you can pass a `File` instance:
await modernTreasury.documents.create({
  documentable_id: '24c6b7a3-02...',
  documentable_type: 'counterparties',
  file: new File(['my bytes'], 'file.txt'),
});

// You can also pass a `fetch` `Response`:
await modernTreasury.documents.create({
  documentable_id: '24c6b7a3-02...',
  documentable_type: 'counterparties',
  file: await fetch('https://somesite/file.txt'),
});

// Finally, if none of the above are convenient, you can use our `toFile` helper:
await modernTreasury.documents.create({
  documentable_id: '24c6b7a3-02...',
  documentable_type: 'counterparties',
  file: await toFile(Buffer.from('my bytes'), 'file.txt'),
});
await modernTreasury.documents.create({
  documentable_id: '24c6b7a3-02...',
  documentable_type: 'counterparties',
  file: await toFile(new Uint8Array([0, 1, 2]), 'file.txt'),
});

Handling errors

When the library is unable to connect to the API, or if the API returns a non-success status code (i.e., 4xx or 5xx response), a subclass of APIError will be thrown:

async function main() {
  const externalAccount = await modernTreasury.externalAccounts
    .create({ counterparty_id: 'missing' })
    .catch((err) => {
      if (err instanceof ModernTreasury.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 followed:

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

Retries

Certain errors will be automatically retried 2 times by default, with a short exponential backoff. Connection errors (for example, due to a network connectivity problem), 409 Conflict, 429 Rate Limit, and >=500 Internal errors will all be retried by default.

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

// Configure the default for all requests:
const modernTreasury = new ModernTreasury({
  maxRetries: 0, // default is 2
  organizationId: 'my-organization-ID',
});

// Or, configure per-request:
await modernTreasury.externalAccounts.list({
  maxRetries: 5,
});

Timeouts

Requests time out after 1 minute by default. You can configure this with a timeout option:

// Configure the default for all requests:
const modernTreasury = new ModernTreasury({
  timeout: 20 * 1000, // 20 seconds (default is 1 minute)
  organizationId: 'my-organization-ID',
});

// Override per-request:
await modernTreasury.externalAccounts.list({ party_name: 'my bank' }, {
  timeout: 5 * 1000,
});

On timeout, an APIConnectionTimeoutError is thrown.

Note that requests which time out will be retried twice by default.

Auto-pagination

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

async function fetchAllExternalAccounts(params) {
  const allExternalAccounts = [];
  // Automatically fetches more pages as needed.
  for await (const externalAccount of modernTreasury.externalAccounts.list()) {
    allExternalAccounts.push(externalAccount);
  }
  return allExternalAccounts;
}

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

let page = await modernTreasury.externalAccounts.list();
for (const externalAccount of page.items) {
  console.log(externalAccount);
}

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

Advanced Usage

Accessing raw Response data (e.g., headers)

The "raw" Response returned by fetch() can be accessed 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 modernTreasury = new ModernTreasury();

const response = await modernTreasury.externalAccounts
  .create({ counterparty_id: '9eba513a-53fd-4d6d-ad52-ccce122ab92a', name: 'my bank' })
  .asResponse();
console.log(response.headers.get('X-My-Header'));
console.log(response.statusText); // access the underlying Response object

const { data: externalAccounts, response: raw } = await modernTreasury.externalAccounts
  .create({ counterparty_id: '9eba513a-53fd-4d6d-ad52-ccce122ab92a', name: 'my bank' })
  .withResponse();
console.log(raw.headers.get('X-My-Header'));
console.log(externalAccounts.id);

Configuring an HTTP(S) Agent (e.g., for proxies)

By default, this library uses a stable agent for all http/https requests to reuse TCP connections, eliminating many TCP & TLS handshakes and shaving around 100ms off most requests.

If you would like to disable or customize this behavior, for example to use the API behind a proxy, you can pass an httpAgent which is used for all requests (be they http or https), for example:

import http from 'http';
import HttpsProxyAgent from 'https-proxy-agent';

// Configure the default for all requests:
const modernTreasury = new ModernTreasury({
  httpAgent: new HttpsProxyAgent(process.env.PROXY_URL),
  organizationId: 'my-organization-ID',
});

// Override per-request:
await modernTreasury.externalAccounts.list({
  baseURL: 'http://localhost:8080/test-api',
  httpAgent: new http.Agent({ keepAlive: false }),
})

Semantic Versioning

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

Changes that only affect static types, without breaking runtime behavior.
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).
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.

We are keen for your feedback; please open an issue with questions, bugs, or suggestions.

Requirements

TypeScript >= 4.5 is supported.

The following runtimes are supported:

Node.js 16 LTS or later (non-EOL) versions.
Deno v1.28.0 or higher, using import ModernTreasury from "npm:modern-treasury". Deno Deploy is not yet supported.
Cloudflare Workers.
Vercel Edge Runtime.

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

euanlau/modern-treasury-node