Massive JS Client

You can enable automatic pagination by passing pagination: true within the globalFetchOptions object when initializing the restClient. When enabled, the client will automatically follow next_url links in the API responses and return the accumulated data.

import { restClient } from '@massive.com/client-js';

const globalFetchOptions = {
	pagination: true,
};

const rest = restClient(process.env.MASSIVE_API_KEY, "https://api.massive.com", globalFetchOptions);

rest.getStocksAggregates({
  stocksTicker: "AAPL",
  multiplier: "1",
  timespan: "day",
  from: "2025-11-01",
  to: "2025-11-30"
}).then((response) => {
	const data = response.data; // convert axios-wrapped response
	const resultCount = data.resultsCount;
	console.log("Result count:", resultCount);
}).catch(e => {
	console.error('An error happened:', e);
});

To make permanent changes to the generated code, you must modify the templates in templates/typescript-axios/ rather than editing src/rest/** directly. The generator uses the -t flag to apply these local templates during the build.

Key templates include:

• apiInner.mustache: Controls the generated API surface.
• common.mustache: Used to add an explicit Promise<R> return type to createRequestFunction. This is a workaround for an Axios issue (tracked as axios/axios#11116) where Axios >= 1.19 defaults a generic to a non-exported symbol, breaking TypeScript declaration emission.

Warning: If you upgrade the openapi-generator version (pinned in openapitools.json), you must re-copy the new upstream templates and re-apply your local changes, or your customizations will be lost.

The TypeScript REST client is automatically generated from the Massive.com OpenAPI specification. While the REST endpoints in src/rest are generated, the WebSocket client (src/websockets/) and the main client glue (src/main.ts) are hand-written and are not affected by regeneration.

To manually regenerate the client from the repository root, ensure you have the openapi-generator JDK on your PATH and that devDependencies are installed via npm ci.

npm run generate

To use the Massive REST and WebSocket API in your project, install the @massive.com/client-js package via npm.

npm install --save '@massive.com/client-js'

Once initialized, use the rest instance to call API methods. Methods are mapped from the OpenAPI specification (e.g., getStocksAggregates, getLastStocksTrade, getLastStocksQuote, getStocksSnapshotTicker).

import { restClient } from '@massive.com/client-js';

const apiKey = "XXXX";
const rest = restClient(apiKey, 'https://api.massive.com');

async function example_getStocksAggregates() {
  try {
    const response = await rest.getStocksAggregates(
      {
        stocksTicker: "AAPL",
        multiplier: "1",
        timespan: "day",
        from: "2025-11-01",
        to: "2025-11-30",
        adjusted: "true",
        sort: "asc",
        limit: "120"
      }
    );
    console.log('Response:', response);
  } catch (e) {
    console.error('An error happened:', e);
  }
}

example_getStocksAggregates();

To use WebSockets, import websocketClient. You can access specific topic clients (like .stocks()) after initializing. Use .send() to subscribe to data and the .onmessage handler to process incoming events.

import { websocketClient } from "@massive.com/client-js";

const stocksWS = websocketClient(process.env.MASSIVE_API_KEY, 'wss://delayed.massive.com').stocks();

stocksWS.onmessage = ({response}) => {
  const [message] = JSON.parse(response);

  // Example subscription
  stocksWS.send('{"action":"subscribe", "params":"AM.MSFT,A.MSFT"}');

  switch (message.ev) {
    case "AM":
      // handle trade message
      break;
    case "A":
      // handle trade message
      break;
  }
};

// Subscribe to a specific ticker
stocksWS.send({ action: "subscribe", params: "T.MSFT" });

Create a REST client instance by importing restClient and providing your API key. You can optionally specify a custom API base URL. By default, the client uses https://api.massive.com.

import { restClient } from '@massive.com/client-js';

// Basic initialization
const rest = restClient(process.env.MASSIVE_API_KEY);

// Initialization with custom base URL
const rest = restClient(process.env.MASSIVE_API_KEY, 'https://api.massive.com');

The following scripts are used to manage the client generation process:

Use getStocksWebsocket to establish a connection to the Massive.com stocks WebSocket stream. It requires an apiKey and accepts an optional apiBase URL (defaults to wss://socket.massive.com). The function returns a websocket.w3cwebsocket instance which you can use to listen for real-time stock events.

import { getStocksWebsocket } from '@massive.com/client-js';

const ws = getStocksWebsocket('YOUR_API_KEY');

ws.onmessage = (event) => {
  const data = JSON.parse(event.data);
  console.log('Received stock event:', data);
};

Use getOptionsWebsocket to establish a connection to the Massive.com Options WebSocket stream. It requires an apiKey and accepts an optional apiBase URL (defaults to wss://socket.massive.com). The function returns a websocket.w3cwebsocket instance which you can use to listen for real-time options data events.

import { getOptionsWebsocket } from '@massive.com/client-js';

const ws = getOptionsWebsocket('YOUR_API_KEY');

ws.onmessage = (event) => {
  const data = JSON.parse(event.data);
  console.log('Received options data:', data);
};

ws.onopen = () => console.log('Connected to Options WebSocket');
ws.onerror = (err) => console.error('WebSocket error:', err);

The BaseAPI class is the foundation for all REST API calls in the client. You can instantiate it with a Configuration object to override the default basePath or provide a custom AxiosInstance for specialized request handling (e.g., adding custom interceptors or middleware).

import { BaseAPI } from '@massive.com/client-js';
import { Configuration } from '@massive.com/client-js';
import axios from 'axios';

const config = new Configuration({ 
  basePath: 'https://custom-api.massive.com' 
});

// You can also pass a custom axios instance
const customAxios = axios.create();
const api = new BaseAPI(config, 'https://custom-api.massive.com', customAxios);