@octokit/auth-app

GitHub App authentication for JavaScript

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auth-app.js
GitHub App authentication for JavaScript

@latest Build Status
@octokit/auth-app implements authentication for GitHub Apps using JSON Web Token, installation access tokens, and OAuth user-to-server access tokens.

- Authenticate as GitHub App (JSON Web Token) - Authenticate as OAuth App (client ID/client secret) - Authenticate as installation - Authenticate as user - JSON Web Token (JWT) Authentication - OAuth App authentication - Installation authentication - User authentication (web flow) - User authentication (device flow) - JSON Web Token (JWT) authentication - OAuth App authentication - Installation access token authentication - GitHub APP user authentication token with expiring disabled - GitHub APP user authentication token with expiring enabled

Standalone usage

Browsers
⚠️ @octokit/auth-app is not meant for usage in the browser. A private key and client secret must not be exposed to users.
The private keys provided by GitHub are in PKCS#1 format, but the WebCrypto API only supports PKCS#8. You need to convert it first:
openssl pkcs8 -topk8 -inform PEM -outform PEM -nocrypt -in private-key.pem -out private-key-pkcs8.key

The OAuth APIs to create user-to-server tokens cannot be used because they do not have CORS enabled.
If you know what you are doing, load @octokit/auth-app directly from cdn.skypack.dev
<script type="module">
  import { createAppAuth } from "https://cdn.skypack.dev/@octokit/auth-app";
</script>

Node
Install with npm install @octokit/auth-app
const { createAppAuth } = require("@octokit/auth-app");
// or: import { createAppAuth } from "@octokit/auth-app";

Authenticate as GitHub App (JSON Web Token)

const auth = createAppAuth({
  appId: 1,
  privateKey: "-----BEGIN PRIVATE KEY-----\n...",
  clientId: "lv1.1234567890abcdef",
  clientSecret: "1234567890abcdef12341234567890abcdef1234",
});

// Retrieve JSON Web Token (JWT) to authenticate as app
const appAuthentication = await auth({ type: "app" });

resolves with
{
  "type": "app",
  "token": "jsonwebtoken123",
  "appId": 123,
  "expiresAt": "2018-07-07T00:09:30.000Z"
}

Authenticate as OAuth App (client ID/client secret)

The OAuth Application APIs require the app to authenticate using clientID/client as Basic Authentication
const auth = createAppAuth({
  appId: 1,
  privateKey: "-----BEGIN PRIVATE KEY-----\n...",
  clientId: "lv1.1234567890abcdef",
  clientSecret: "1234567890abcdef12341234567890abcdef1234",
});

const appAuthentication = await auth({
  type: "oauth-app",
});

resolves with
{
  "type": "oauth-app",
  "clientId": "lv1.1234567890abcdef",
  "clientSecret": "1234567890abcdef1234567890abcdef12345678",
  "headers": {
    "authorization": "basic bHYxLjEyMzQ1Njc4OTBhYmNkZWY6MTIzNDU2Nzg5MGFiY2RlZjEyMzQ1Njc4OTBhYmNkZWYxMjM0NTY3OA=="
  }
}

Authenticate as installation

const auth = createAppAuth({
  appId: 1,
  privateKey: "-----BEGIN PRIVATE KEY-----\n...",
  clientId: "lv1.1234567890abcdef",
  clientSecret: "1234567890abcdef12341234567890abcdef1234",
});

// Retrieve installation access token
const installationAuthentication = await auth({
  type: "installation",
  installationId: 123,
});

resolves with
{
  "type": "token",
  "tokenType": "installation",
  "token": "token123",
  "installationId": 123,
  "createdAt": "2018-07-07T00:00:00.000Z",
  "expiresAt": "2018-07-07T00:59:00.000Z"
}

Authenticate as user

const auth = createAppAuth({
  appId: 1,
  privateKey: "-----BEGIN PRIVATE KEY-----\n...",
  clientId: "lv1.1234567890abcdef",
  clientSecret: "1234567890abcdef12341234567890abcdef1234",
});

// Retrieve an oauth-access token
const userAuthentication = await auth({ type: "oauth-user", code: "123456" });

Resolves with
{
  "type": "token",
  "tokenType": "oauth",
  "token": "token123"
}

Usage with Octokit


Browsers

⚠️ @octokit/auth-app is not meant for usage in the browser. A private key and client secret must not be exposed to users.
The private keys provided by GitHub are in PKCS#1 format, but the WebCrypto API only supports PKCS#8. You need to convert it first:
openssl pkcs8 -topk8 -inform PEM -outform PEM -nocrypt -in private-key.pem -out private-key-pkcs8.key

The OAuth APIs to create user-to-server tokens cannot be used because they do not have CORS enabled.
If you know what you are doing, load @octokit/auth-app and @octokit/core (or a compatible module) directly from cdn.skypack.dev
<script type="module">
  import { createAppAuth } from "https://cdn.skypack.dev/@octokit/auth-app";
  import { Octokit } from "https://cdn.skypack.dev/@octokit/core";
</script>


Node

Install with npm install @octokit/core @octokit/auth-app. Optionally replace @octokit/core with a compatible module
const { Octokit } = require("@octokit/core");
const { createAppAuth, createOAuthUserAuth } = require("@octokit/auth-app");


const appOctokit = new Octokit({
  authStrategy: createAppAuth,
  auth: {
    appId: 1,
    privateKey: "-----BEGIN PRIVATE KEY-----\n...",
    clientId: "1234567890abcdef1234",
    clientSecret: "1234567890abcdef1234567890abcdef12345678",
  },
});

// Send requests as GitHub App
const { slug } = await appOctokit.request("GET /user");
console.log("authenticated as %s", slug);

// Send requests as OAuth App
await appOctokit.request("POST /application/{client_id}/token", {
  client_id: "1234567890abcdef1234",
  access_token: "existingtoken123",
});
console.log("token is valid");

// create a new octokit instance that is authenticated as the user
const userOctokit = await appOctokit.auth({
  type: "oauth-user",
  code: "code123",
  factory: (options) => {
    return new Octokit({
      authStrategy: createOAuthUserAuth,
      auth: options,
    });
  },
});

// Exchanges the code for the user access token authentication on first request
// and caches the authentication for successive requests
const {
  data: { login },
} = await userOctokit.request("GET /user");
console.log("Hello, %s!", login);

In order to create an octokit instance that is authenticated as an installation, with automated installation token refresh, set installationId as auth option
const installationOctokit = new Octokit({
  authStrategy: createAppAuth,
  auth: {
    appId: 1,
    privateKey: "-----BEGIN PRIVATE KEY-----\n...",
    installationId: 123,
  },
});

// transparently creates an installation access token the first time it is needed
// and refreshes it when it expires
await installationOctokit.request("POST /repos/{owner}/{repo}/issues", {
  owner: "octocat",
  repo: "hello-world",
  title: "title",
});

createAppAuth(options) or new Octokit({ auth })

<tr>
  <th width=150>
    name
  </th>
  <th width=70>
    type
  </th>
  <th>
    description
  </th>
</tr>
<tr>
  <th>
    <code>appId</code>
  </th>
  <th>
    <code>number</code>
  </th>
  <td>
    <strong>Required</strong>. Find <strong>App ID</strong> on the app’s about page in settings.
  </td>
</tr>
<tr>
  <th>
    <code>privateKey</code>
  </th>
  <th>
    <code>string</code>
  </th>
  <td>
    <strong>Required</strong>. Content of the <code>*.pem</code> file you downloaded from the app’s about page. You can generate a new private key if needed.
  </td>
</tr>
<tr>
  <th>
    <code>installationId</code>
  </th>
  <th>
    <code>number</code>
  </th>
  <td>
    Default <code>installationId</code> to be used when calling <code>auth({ type: "installation" })</code>.
  </td>
</tr>
<tr>
  <th>
    <code>clientId</code>
  </th>
  <th>
    <code>string</code>
  </th>
  <td>
    The client ID of the GitHub App.
  </td>
</tr>
<tr>
  <th>
    <code>clientSecret</code>
  </th>
  <th>
    <code>string</code>
  </th>
  <td>
    A client secret for the GitHub App.
  </td>
</tr>
<tr>
  <th>
    <code>request</code>
  </th>
  <th>
    <code>function</code>
  </th>
  <td>
Automatically set to octokit.request when using with an Octokit constructor.
For standalone usage, you can pass in your own @octokit/request instance. For usage with enterprise, set baseUrl to the hostname + /api/v3. Example:
const { request } = require("@octokit/request");
createAppAuth({
  appId: 1,
  privateKey: "-----BEGIN PRIVATE KEY-----\n...",
  request: request.defaults({
    baseUrl: "https://ghe.my-company.com/api/v3",
  }),
});

<tr>
  <th>
    <code>cache</code>
  </th>
  <th>
    <code>object</code>
  </th>
  <td>
    Installation tokens expire after an hour. By default, <code>@octokit/auth-app</code> is caching up to 15000 tokens simultaneously using <a href="https://github.com/isaacs/node-lru-cache">lru-cache</a>. You can pass your own cache implementation by passing <code>options.cache.{get,set}</code> to the constructor. Example:
const CACHE = {};
createAppAuth({
  appId: 1,
  privateKey: "-----BEGIN PRIVATE KEY-----\n...",
  cache: {
    async get(key) {
      return CACHE[key];
    },
    async set(key, value) {
      CACHE[key] = value;
    },
  },
});

<th>
  <code>log</code>
</th>
<th>
  <code>object</code>
</th>
<td>
  You can pass in your preferred logging tool by passing <code>option.log</code> to the constructor. If you would like to make the log level configurable using an environment variable or external option, we recommend the console-log-level package. For example:
createAppAuth({
  appId: 1,
  privateKey: "-----BEGIN PRIVATE KEY-----\n...",
  log: require("console-log-level")({ level: "info" }),
});

auth(options) or octokit.auth(options)

The async auth() method accepts different options depending on your use case

JSON Web Token (JWT) Authentication

Authenticate as the GitHub app to list installations, repositories, and create installation access tokens.
<tr>
  <th width=150>
    name
  </th>
  <th width=70>
    type
  </th>
  <th>
    description
  </th>
</tr>
<tr>
  <th>
    <code>type</code>
  </th>
  <th>
    <code>string</code>
  </th>
  <td>
    <strong>Required</strong>. Must be either <code>"app"</code>.
  </td>
</tr>

OAuth App authentication

Create, reset, refresh, delete OAuth user-to-server tokens
<tr>
  <th width=150>
    name
  </th>
  <th width=70>
    type
  </th>
  <th>
    description
  </th>
</tr>
<tr>
  <th>
    <code>type</code>
  </th>
  <th>
    <code>string</code>
  </th>
  <td>
    <strong>Required</strong>. Must be either <code>"oauth-app"</code>.
  </td>
</tr>

Installation authentication

<tr>
  <th width=150>
    name
  </th>
  <th width=70>
    type
  </th>
  <th>
    description
  </th>
</tr>
<tr>
  <th>
    <code>type</code>
  </th>
  <th>
    <code>string</code>
  </th>
  <td>
    <strong>Required</strong>. Must be <code>"installation"</code>.
  </td>
</tr>
<tr>
  <th>
    <code>installationId</code>
  </th>
  <th>
    <code>number</code>
  </th>
  <td>
    <strong>Required unless a default <code>installationId</code> was passed to <code>createAppAuth()</code></strong>. ID of installation to retrieve authentication for.
  </td>
</tr>
<tr>
  <th>
    <code>repositoryIds</code>
  </th>
  <th>
    <code>array of numbers</code>
  </th>
  <td>
    The <code>id</code> of the repositories that the installation token can access. Also known as a <code>databaseID</code> when querying the repository object in GitHub's GraphQL API. This option is **(recommended)** over <code>repositoryNames</code> when needing to limit the scope of the access token, due to <code>repositoryNames</code> having the possibility of changing. Additionally, you should only include either <code>repositoryIds</code> or <code>repositoryNames</code>, but not both.
  </td>
</tr>
<tr>
  <th>
    <code>repositoryNames</code>
  </th>
  <th>
    <code>array of strings</code>
  </th>
  <td>
    The <code>name</code> of the repositories that the installation token can access. As mentioned in the <code>repositoryIds</code> description, you should only include either <code>repositoryIds</code> or <code>repositoryNames</code>, but not both.
  </td>
</tr>
<tr>
  <th>
    <code>permissions</code>
  </th>
  <th>
    <code>object</code>
  </th>
  <td>
    The permissions granted to the access token. The permissions object includes the permission names and their access type. For a complete list of permissions and allowable values, see <a href="https://docs.github.com/en/developers/apps/creating-a-github-app-using-url-parameters#github-app-permissions">GitHub App permissions</a>.
  </td>
</tr>
<tr>
  <th>
    <code>factory</code>
  </th>
  <th>
    <code>function</code>
  </th>
  <td>
The auth({type: "installation", installationId, factory }) call with resolve with whatever the factory function returns. The factory function will be called with all the strategy option that auth was created with, plus the additional options passed to auth, besides type and factory.
For example, you can create a new auth instance for an installation which shares the internal state (especially the access token cache) with the calling auth instance:
const appAuth = createAppAuth({
  appId: 1,
  privateKey: "-----BEGIN PRIVATE KEY-----\n...",
});

const installationAuth123 = await appAuth({
  type: "installation",
  installationId: 123,
  factory: createAppAuth,
});

</tr>
<tr>
  <th>
    <code>refresh</code>
  </th>
  <th>
    <code>boolean</code>
  </th>
  <td>
Installation tokens expire after one hour. By default, tokens are cached and returned from cache until expired. To bypass and update a cached token for the given installationId, set refresh to true.
Defaults to false.
</tr>

User authentication (web flow)

Exchange code received from the web flow redirect described in step 2 of GitHub's OAuth web flow
<tr>
  <th width=150>
    name
  </th>
  <th width=70>
    type
  </th>
  <th>
    description
  </th>
</tr>
<tr>
  <th>
    <code>type</code>
  </th>
  <th>
    <code>string</code>
  </th>
  <td>
    <strong>Required</strong>. Must be <code>"oauth-user"</code>.
  </td>
</tr>
<tr>
  <th>
    <code>factory</code>
  </th>
  <th>
    <code>function</code>
  </th>
  <td>
The auth({type: "oauth-user", factory }) call with resolve with whatever the factory function returns. The factory function will be called with all the strategy option that auth was created with, plus the additional options passed to auth, besides type and factory.
For example, you can create a new auth instance for an installation which shares the internal state (especially the access token cache) with the calling auth instance:
const {
  createAppAuth,
  createOAuthUserAuth,
} = require("@octokit/auth-oauth-app");

const appAuth = createAppAuth({
  appId: 1,
  privateKey: "-----BEGIN PRIVATE KEY-----\n...",
  clientId: "lv1.1234567890abcdef",
  clientSecret: "1234567890abcdef1234567890abcdef12345678",
});

const userAuth = await appAuth({
  type: "oauth-user",
  code,
  factory: createOAuthUserAuth,
});

// will create token upon first call, then cache authentication for successive calls,
// until token needs to be refreshed (if enabled for the GitHub App)
const authentication = await userAuth();

</tr>
<tr>
  <th>
    <code>code</code>
  </th>
  <th>
    <code>string</code>
  </th>
  <td>
    The authorization <code>code</code> which was passed as query parameter to the callback URL from the <a href="https://docs.github.com/en/developers/apps/authorizing-oauth-apps#2-users-are-redirected-back-to-your-site-by-github">OAuth web application flow</a>.
  </td>
</tr>
<tr>
  <th>
    <code>redirectUrl</code>
  </th>
  <th>
    <code>string</code>
  </th>
  <td>
    The URL in your application where users are sent after authorization. See <a href="https://docs.github.com/en/developers/apps/authorizing-oauth-apps#redirect-urls">redirect urls</a>.
  </td>
</tr>
<tr>
  <th>
    <code>state</code>
  </th>
  <th>
    <code>string</code>
  </th>
  <td>
    The unguessable random string you provided in Step 1 of the <a href="https://docs.github.com/en/developers/apps/authorizing-oauth-apps#2-users-are-redirected-back-to-your-site-by-github">OAuth web application flow</a>.
  </td>
</tr>

User authentication (device flow)

Create a token using GitHub's device flow.
The device flow does not require a client secret, but it is required as strategy option for @octokit/auth-app, even for the device flow. If you want to implement the device flow without requiring a client secret, use @octokit/auth-oauth-device.
<tr>
  <th width=150>
    name
  </th>
  <th width=70>
    type
  </th>
  <th>
    description
  </th>
</tr>
<tr>
  <th>
    <code>type</code>
  </th>
  <th>
    <code>string</code>
  </th>
  <td>
    <strong>Required</strong>. Must be <code>"oauth-user"</code>.
  </td>
</tr>
<tr>
  <th>
    <code>onVerification</code>
  </th>
  <th>
    <code>function</code>
  </th>
  <td>
Required. A function that is called once the device and user codes were retrieved.
The onVerification() callback can be used to pause until the user completes step 2, which might result in a better user experience.
const auth = auth({
  type: "oauth-user",
  onVerification(verification) {
    console.log("Open %s", verification.verification_uri);
    console.log("Enter code: %s", verification.user_code);
    await prompt("press enter when you are ready to continue");
  },
});

</tr>
<tr>
  <th>
    <code>factory</code>
  </th>
  <th>
    <code>function</code>
  </th>
  <td>
The auth({type: "oauth-user", factory }) call with resolve with whatever the factory function returns. The factory function will be called with all the strategy option that auth was created with, plus the additional options passed to auth, besides type and factory.
For example, you can create a new auth instance for an installation which shares the internal state (especially the access token cache) with the calling auth instance:
const {
  createAppAuth,
  createOAuthUserAuth,
} = require("@octokit/auth-oauth-app");

const appAuth = createAppAuth({
  appId: 1,
  privateKey: "-----BEGIN PRIVATE KEY-----\n...",
  clientId: "lv1.1234567890abcdef",
  clientSecret: "1234567890abcdef1234567890abcdef12345678",
});

const userAuth = await appAuth({
  type: "oauth-user",
  code,
  factory: createOAuthUserAuth,
});

// will create token upon first call, then cache authentication for successive calls,
// until token needs to be refreshed (if enabled for the GitHub App)
const authentication = await userAuth();

</tr>

Authentication object

Depending on on the auth() call, the resulting authentication object can be one of
  1. JSON Web Token (JWT) authentication
  2. OAuth App authentication
  3. Installation access token authentication
  4. GitHub APP user authentication token with expiring disabled
  5. GitHub APP user authentication token with expiring enabled

JSON Web Token (JWT) authentication

<tr>
  <th width=150>
    name
  </th>
  <th width=70>
    type
  </th>
  <th>
    description
  </th>
</tr>
<tr>
  <th>
    <code>type</code>
  </th>
  <th>
    <code>string</code>
  </th>
  <td>
    <code>"app"</code>
  </td>
</tr>
<tr>
  <th>
    <code>token</code>
  </th>
  <th>
    <code>string</code>
  </th>
  <td>
    The JSON Web Token (JWT) to authenticate as the app.
  </td>
</tr>
<tr>
  <th>
    <code>appId</code>
  </th>
  <th>
    <code>number</code>
  </th>
  <td>
    GitHub App database ID.
  </td>
</tr>
<tr>
  <th>
    <code>expiresAt</code>
  </th>
  <th>
    <code>string</code>
  </th>
  <td>
    Timestamp in UTC format, e.g. <code>"2018-07-07T00:09:30.000Z"</code>. A Date object can be created using <code>new Date(authentication.expiresAt)</code>.
  </td>
</tr>

OAuth App authentication

<tr>
  <th width=150>
    name
  </th>
  <th width=70>
    type
  </th>
  <th>
    description
  </th>
</tr>
<tr>
  <th>
    <code>type</code>
  </th>
  <th>
    <code>string</code>
  </th>
  <td>
    <code>"oauth-app"</code>
  </td>
</tr>
<tr>
  <th>
    <code>clientType</code>
  </th>
  <th>
    <code>string</code>
  </th>
  <td>
    <code>"github-app"</code>
  </td>
</tr>
<tr>
  <th>
    <code>clientId</code>
  </th>
  <th>
    <code>string</code>
  </th>
  <td>
    The client ID as passed to the constructor.
  </td>
</tr>
<tr>
  <th>
    <code>clientSecret</code>
  </th>
  <th>
    <code>string</code>
  </th>
  <td>
    The client secret as passed to the constructor.
  </td>
</tr>
<tr>
  <th>
    <code>headers</code>
  </th>
  <th>
    <code>object</code>
  </th>
  <td>
    <code>{ authorization }</code>.
  </td>
</tr>

Installation access token authentication

<tr>
  <th width=150>
    name
  </th>
  <th width=70>
    type
  </th>
  <th>
    description
  </th>
</tr>
<tr>
  <th>
    <code>type</code>
  </th>
  <th>
    <code>string</code>
  </th>
  <td>
    <code>"token"</code>
  </td>
</tr>
<tr>
  <th>
    <code>token</code>
  </th>
  <th>
    <code>string</code>
  </th>
  <td>
    The installation access token.
  </td>
</tr>
<tr>
  <th>
    <code>tokenType</code>
  </th>
  <th>
    <code>string</code>
  </th>
  <td>
    <code>"installation"</code>
  </td>
</tr>
<tr>
  <th>
    <code>installationId</code>
  </th>
  <th>
    <code>number</code>
  </th>
  <td>
    Installation database ID.
  </td>
</tr>
<tr>
  <th>
    <code>createdAt</code>
  </th>
  <th>
    <code>string</code>
  </th>
  <td>
    Timestamp in UTC format, e.g. <code>"2018-07-07T00:00:00.000Z"</code>. A Date object can be created using <code>new Date(authentication.expiresAt)</code>.
  </td>
</tr>
<tr>
  <th>
    <code>expiresAt</code>
  </th>
  <th>
    <code>string</code>
  </th>
  <td>
    Timestamp in UTC format, e.g. <code>"2018-07-07T00:59:00.000Z"</code>. A Date object can be created using <code>new Date(authentication.expiresAt)</code>.
  </td>
</tr>
<tr>
  <th>
    <code>repositoryIds</code>
  </th>
  <th>
    <code>array of numbers</code>
  </th>
  <td>
    Only present if <code>repositoryIds</code> option passed to <code>auth(options)</code>.
  </td>
</tr>
<tr>
  <th>
    <code>repositoryNames</code>
  </th>
  <th>
    <code>array of strings</code>
  </th>
  <td>
    Only present if <code>repositoryNames</code> option passed to <code>auth(options)</code>.
  </td>
</tr>
<tr>
  <th>
    <code>permissions</code>
  </th>
  <th>
    <code>object</code>
  </th>
  <td>
    An object where keys are the permission name and the value is either <code>"read"</code> or <code>"write"</code>. See the list of all <a href="https://docs.github.com/en/rest/reference/permissions-required-for-github-apps">GitHub App Permissions</a>.
  </td>
</tr>
<tr>
  <th>
    <code>singleFileName</code>
  </th>
  <th>
    <code>string</code>
  </th>
  <td>
    If the <a herf="https://docs.github.com/en/rest/reference/permissions-required-for-github-apps#permission-on-single-file">single file permission</a> is enabled, the <code>singleFileName</code> property is set to the path of the accessible file.
  </td>
</tr>

GitHub APP user authentication token with expiring disabled

<tr>
  <th width=150>
    name
  </th>
  <th width=70>
    type
  </th>
  <th>
    description
  </th>
</tr>
<tr>
  <th>
    <code>type</code>
  </th>
  <th>
    <code>string</code>
  </th>
  <td>
    <code>"token"</code>
  </td>
</tr>
<tr>
  <th>
    <code>tokenType</code>
  </th>
  <th>
    <code>string</code>
  </th>
  <td>
    <code>"oauth"</code>
  </td>
</tr>
<tr>
  <th>
    <code>clientType</code>
  </th>
  <th>
    <code>string</code>
  </th>
  <td>
    <code>"github-app"</code>
  </td>
</tr>
<tr>
  <th>
    <code>clientId</code>
  </th>
  <th>
    <code>string</code>
  </th>
  <td>
    The app's <code>Client ID</code>
  </td>
</tr>
<tr>
  <th>
    <code>clientSecret</code>
  </th>
  <th>
    <code>string</code>
  </th>
  <td>
    One of the app's client secrets
  </td>
</tr>
<tr>
  <th>
    <code>token</code>
  </th>
  <th>
    <code>string</code>
  </th>
  <td>
    The user access token
  </td>
</tr>

GitHub APP user authentication token with expiring enabled

<tr>
  <th width=150>
    name
  </th>
  <th width=70>
    type
  </th>
  <th>
    description
  </th>
</tr>
<tr>
  <th>
    <code>type</code>
  </th>
  <th>
    <code>string</code>
  </th>
  <td>
    <code>"token"</code>
  </td>
</tr>
<tr>
  <th>
    <code>tokenType</code>
  </th>
  <th>
    <code>string</code>
  </th>
  <td>
    <code>"oauth"</code>
  </td>
</tr>
<tr>
  <th>
    <code>clientType</code>
  </th>
  <th>
    <code>string</code>
  </th>
  <td>
    <code>"github-app"</code>
  </td>
</tr>
<tr>
  <th>
    <code>clientId</code>
  </th>
  <th>
    <code>string</code>
  </th>
  <td>
    The app's <code>Client ID</code>
  </td>
</tr>
<tr>
  <th>
    <code>clientSecret</code>
  </th>
  <th>
    <code>string</code>
  </th>
  <td>
    One of the app's client secrets
  </td>
</tr>
<tr>
  <th>
    <code>token</code>
  </th>
  <th>
    <code>string</code>
  </th>
  <td>
    The user access token
  </td>
</tr>
<tr>
  <th>
    <code>refreshToken</code>
  </th>
  <th>
    <code>string</code>
  </th>
  <td>
    The refresh token
  </td>
</tr>
<tr>
  <th>
    <code>expiresAt</code>
  </th>
  <th>
    <code>string</code>
  </th>
  <td>
    Date timestamp in <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Date/toISOString">ISO 8601</a> standard. Example: <code>2022-01-01T08:00:0.000Z</code>
  </td>
</tr>
<tr>
  <th>
    <code>refreshTokenExpiresAt</code>
  </th>
  <th>
    <code>string</code>
  </th>
  <td>
    Date timestamp in <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Date/toISOString">ISO 8601</a> standard. Example: <code>2021-07-01T00:00:0.000Z</code>
  </td>
</tr>

auth.hook(request, route, parameters) or auth.hook(request, options)

auth.hook() hooks directly into the request life cycle. It amends the request to authenticate either as app or as installation based on the request URL. Although the "machine-man" preview has graduated to the official API, https://developer.github.com/changes/2020-08-20-graduate-machine-man-and-sailor-v-previews/, it is still required in versions of GitHub Enterprise up to 2.21 so it automatically sets the "machine-man" preview for all endpoints requiring JWT authentication.
The request option is an instance of @octokit/request. The arguments are the same as for the request() method.
auth.hook() can be called directly to send an authenticated request
const { data: installations } = await auth.hook(
  request,
  "GET /app/installations"
);

Or it can be passed as option to request().
const requestWithAuth = request.defaults({
  request: {
    hook: auth.hook,
  },
});

const { data: installations } = await requestWithAuth("GET /app/installations");

Note that auth.hook() does not create and set an OAuth authentication token. But you can use @octokit/auth-oauth-app for that functionality. And if you don't plan on sending requests to routes that require authentication with client_id and client_secret, you can just retrieve the token and then create a new instance of request() with the authentication header set:
const { token } = await auth({
  type: "oauth-user",
  code: "123456",
});
const requestWithAuth = request.defaults({
  headers: {
    authentication: `token ${token}`,
  },
});

Types

import {
  // strategy options
  StrategyOptions,
  // auth options
  AuthOptions,
  AppAuthOptions,
  OAuthAppAuthOptions,
  InstallationAuthOptions,
  OAuthWebFlowAuthOptions,
  OAuthDeviceFlowAuthOptions,
  // authentication objects
  Authentication,
  AppAuthentication,
  OAuthAppAuthentication,
  InstallationAccessTokenAuthentication,
  GitHubAppUserAuthentication,
  GitHubAppUserAuthenticationWithExpiration,
} from "@octokit/auth-app";

Implementation details

When creating a JSON Web Token, it sets the "issued at time" (iat) to 30s in the past as we have seen people running situations where the GitHub API claimed the iat would be in future. It turned out the clocks on the different machine were not in sync.
Installation access tokens are valid for 60 minutes. This library invalidates them after 59 minutes to account for request delays.
All OAuth features are implemented internally using @octokit/auth-oauth-app.

License

MIT