Introduction #

We welcome developers to build applications and products that are powered by Alpaca while also protecting the privacy and security of our users. To build using Alpaca’s APIs, please follow the guide below.

Alpaca implements OAuth 2.0 to allow third party applications to access Alpaca Trading API on behalf of the end-users. This document describes how you can integrate with Alpaca through OAuth.

Note that these materials are supplementary to our API documentation. Please read the API documentation for topics outside of OAuth integration.

How To Get Access Tokens #

Once the application is registered, we will issue a Client ID and Client Secret for it.

To integrate your application with Alpaca, use the following flow:

Flow Chart

1: End user requests service from application. Application redirect users to request Alpaca access #

GET https://app.alpaca.markets/oauth/authorize?response_type=code&client_id=YOUR_CLIENT_ID&redirect_uri=YOUR_REDIRECT_URL&state=SOMETHING_RANDOM&scope=account:write%20trading

When redirecting a user to Alpaca to authorize access to your application, you’ll need to construct the authorization URL with the correct parameters and scopes. Here’s a list of parameters you should always specify:

Parameter Description
response_type Required Must be code to request an authorization code.
client_id Required The Client ID you received when you registered the application.
redirect_uri Required The URL where the user will be sent after authorization. It must match one of the whitelisted redirect URIs for your application.
state Optional An unguessable random string, used to protect against request forgery attacks.
scope Optional A space-delimited list of scopes your application requests access to. Read-only endpoint access is assumed by default.

Allowed Scopes:

Scope Description
account:write Write access for account configurations and watchlists.
trading Place, cancel or modify orders.
data Access to the Data API.

Example authorization URL:

GET https://app.alpaca.markets/oauth/authorize?response_type=code&client_id=fc9c55efa3924f369d6c1148e668bbe8&redirect_uri=https%3A%2F%2Fexample.com%2Foauth%2Fcallback&state=8e02c9c6a3484fadaaf841fb1df290e1&scope=account:write%20trading

2: End user authorizes API access for the applications #

From the user side, they will see the following authorization screen:

Authorization Page

3: Alpaca redirects end user to application with an authorization code #

If the user approves access, Alpaca will redirect them back to your redirect_uri with a temporary code parameter. If you specified a state parameter in step 1, it will be returned as well. The parameter will always match the value specified in step 1. If the values don’t match, the request should not be trusted.

Example of the redirect:

GET https://example.com/oauth/callback?code=67f74f5a-a2cc-4ebd-88b4-22453fe07994&state=8e02c9c6a3484fadaaf841fb1df290e1

4: Application receives the authorization code #

You can use this code to exchange for an access token.

5: Application exchanges the authorization code with an access token from Alpaca #

After you have received the temporary code, you can exchange it for an access token. This can be done by making a POST call:

POST https://api.alpaca.markets/oauth/token

With following parameters:

Parameter Description
grant_type Required Must be set to authorization_code for an access token request.
code Required The authorization code received in step 4
client_id Required The Client ID you received when you registered the application.
client_secret Required The Client Secret you received when you registered the application.
redirect_uri Required The redirect URI you used for the authorization code request.

Note: this request should take place behind-the-scenes from your backend server and shouldn’t be visible to the end users for security purposes.

The content type must be application/x-www-form-urlencoded as defined in RFC.

Example request:

curl -X POST https://api.alpaca.markets/oauth/token \
  -d 'grant_type=authorization_code&code=67f74f5a-a2cc-4ebd-88b4-22453fe07994&client_id=fc9c55efa3924f369d6c1148e668bbe8&client_secret=5b8027074d8ab434882c0806833e76508861c366&redirect_uri=https://example.com/oauth/callback'

After a successful request, a valid access token will be returned in the response:

{
    "access_token": "79500537-5796-4230-9661-7f7108877c60",
    "token_type": "bearer",
    "scope": "account:write trading"
}

API Calls #

Once you have integrated and have a valid access token you can start make calls to Alpaca Trading API v2 on behalf of the end-user.

Example requests:

curl https://api.alpaca.markets/v2/account /
  -H 'Authorization: Bearer 79500537-5796-4230-9661-7f7108877c60'
curl https://paper-api.alpaca.markets/v2/orders /
  -H 'Authorization: Bearer 79500537-5796-4230-9661-7f7108877c60'

The OAuth token can also be used for the trade update websockets stream.

{
  "action": "authenticate",
  "data": {
    "oauth_token": "79500537-5796-4230-9661-7f7108877c60"
  }
}