Node.js Tesla API

This is a working draft code to interact with Tesla Fleet API and Vehicle Command API using signed protobuf messages.

This is a very stripped down version ported from original Go code, with the purpose of understanding the basics of protobuf message signing.

Usage

The following code assumes that you have already the OAuth tokens and the public and private key pair.

It will read the access_token and refresh_token from a json file, and the key pair from a .pem file.

import fs from 'fs';
import eckey from 'eckey-utils';
import { FleetApi } from './src/FleetApi.js';
import { CarServer } from './src/CarServer.js';

// Load OAuth tokens
const cfg = JSON.parse(fs.readFileSync('oauth.json'));

// Load private and public keys
const key = eckey.parsePem(fs.readFileSync('private_key.pem', 'utf8').trim());

// Fleet api config
const fleetApi = new FleetApi(cfg.client_id, cfg.access_token, cfg.refresh_token);

// CarServer initialization
const cmdApi = new CarServer(fleetApi, cfg.vin, key);

await cmdApi.startSession();
await cmdApi.chargingSetLimit(80);

The code is composed by three classes:

• FleetApi, which will forward the commands to Tesla API server.
• CarServer, which implements the protobuf protocol.
• Signer, which is an internal class used by CarServer to sign the messages.

Requirements

You need to obtain both an OAuth token for Fleet Api, and a private key to send commands. For more details, refer to Tesla Fleet Api docs.

Obtaining OAuth tokens

To abtain the authentication tokens, you need to register a third-party account at https://developer.tesla.com. Currently, you must be a bussines entity to complete the registration.

Once registered, you must submit your app details and will obtain the client-id and client-secret codes, which will be used to generate the OAuth third-party tokens.

Here is the procedure:

1. Set-up one or more "Allowed Redirect URI(s)" in the app configuration. Like for example: https://your_domain/redirect_path

2. Point your browser to the following address:

   https://auth.tesla.com/oauth2/v3/authorize?&client_id=$CLIENT_ID&locale=it-IT&prompt=login&redirect_uri=$REDIRECT_URI&response_type=code&scope=$SCOPE&state=$STATE`
   

   Where:

   • CLIENT_ID = your_app_client_id
   • REDIRECT_URI = https://your_domain/redirect_path
   • SCOPE = openid%20vehicle_device_data%20offline_access
   • STATE = 7baf90cda7baf90cda7baf90cda (random string)

   For the full list of authorization scopes see here.

3. You will be prompted to authenticate with a Tesla client account, on behalf of which the commands will be sent (it can be different from the developer account), and you must authorize the app to use the Fleet API.

4. The browser will then redirect to the forementioned URI, passing the following parameters via GET method:

   (
       "locale": "it-IT"
       "code": "EU_ab012dfegh...."
       "state": "ZjQwZDE1YjRjOWJi"
       "issuer": "https://auth.tesla.com/oauth2/v3"
   )

5. Using the "code" value, you can generete the OAuth tokens making the following POST request:

   # Authorization code token request
   CODE=<extract from callback>
   curl --request POST \
   --header 'Content-Type: application/x-www-form-urlencoded' \
   --data-urlencode 'grant_type=authorization_code' \
   --data-urlencode "client_id=$CLIENT_ID" \
   --data-urlencode "client_secret=$CLIENT_SECRET" \
   --data-urlencode "code=$CODE" \
   --data-urlencode "audience=$AUDIENCE" \
   --data-urlencode "redirect_uri=$CALLBACK" \
   'https://auth.tesla.com/oauth2/v3/token'
   # Extract access_token and refresh_token from this response
   

6. The access_token will expire after 8 hours, and to obtain new tokens you must make the following POST call:

   # Refresh token request
   REFRESH_TOKEN=the_last_valid_refresh_token
   curl --request POST \
   --header 'Content-Type: application/x-www-form-urlencoded' \
   --data-urlencode 'grant_type=refresh_token' \
   --data-urlencode "client_id=$CLIENT_ID" \
   --data-urlencode "refresh_token=$REFRESH_TOKEN" \
   'https://auth.tesla.com/oauth2/v3/token'
   

More info here: https://developer.tesla.com/docs/fleet-api#authentication.

Obtaining private and public key pair

You can generate the keys using the Tesla command line interface available at https://github.com/teslamotors/vehicle-command.

Download the Go code and build it. You will get some executable commands in the bin folder.

Run the tesla-keygen command to generate a key pair and save it to disk, like the following example:

tesla-keygen -key-file ~/tesla_private.key -keyring-type file create

This will save the key pair in PEM format in a file in your home folder.