const auth = new GoogleAuth({
  scopes: 'https://www.googleapis.com/auth/cloud-platform',
  // Pass the project ID explicitly to avoid the need to grant `roles/browser` to the service account
  // or enable Cloud Resource Manager API on the project.
  projectId: 'CLOUD_RESOURCE_PROJECT_ID',
});
<pre class="typing-tooltip"><code data-language="javascript" class="language-javascript"><span class="token keyword">const</span> auth<span class="token operator">:</span> <span class="token builtin">any</span></code></pre>

// Make a request to a protected Cloud Identity-Aware Proxy (IAP) resource
const {GoogleAuth} = require('google-auth-library');

async function main()
  const targetAudience = 'iap-client-id';
  const url = 'https://iap-url.com';
  const auth = new GoogleAuth();
  const client = await auth.getIdTokenClient(targetAudience);
  const res = await client.request({url});
  console.log(res.data);
}

main().catch(console.error);
<pre class="typing-tooltip"><code data-language="javascript" class="language-javascript"><span class="token punctuation">(</span>alias<span class="token punctuation">)</span> <span class="token keyword">class</span> <span class="token class-name">GoogleAuth</span>
<span class="token keyword">import</span> GoogleAuth</code></pre>

// Make a request to a protected Cloud Run service.
const {GoogleAuth} = require('google-auth-library');

async function main() {
  const url = 'https://cloud-run-1234-uc.a.run.app';
  const auth = new GoogleAuth();
  const client = await auth.getIdTokenClient(url);
  const res = await client.request({url});
  console.log(res.data);
}

main().catch(console.error);
<pre class="typing-tooltip"><code data-language="javascript" class="language-javascript"><span class="token punctuation">(</span>alias<span class="token punctuation">)</span> <span class="token keyword">class</span> <span class="token class-name">GoogleAuth</span>
<span class="token keyword">import</span> GoogleAuth</code></pre>

const {GoogleAuth} = require('google-auth-library');

/**
* Instead of specifying the type of client you'd like to use (JWT, OAuth2, etc)
* this library will automatically choose the right client based on the environment.
*/
async function main() {
  const auth = new GoogleAuth({
    scopes: 'https://www.googleapis.com/auth/cloud-platform'
  });
  const client = await auth.getClient();
  const projectId = await auth.getProjectId();
  const url = `https://dns.googleapis.com/dns/v1/projects/${projectId}`;
  const res = await client.request({ url });
  console.log(res.data);
}

main().catch(console.error);
<pre class="typing-tooltip"><code data-language="javascript" class="language-javascript"><span class="token punctuation">(</span>alias<span class="token punctuation">)</span> <span class="token keyword">class</span> <span class="token class-name">GoogleAuth</span>
<span class="token keyword">import</span> GoogleAuth</code></pre>

async function main() {
  const auth = new GoogleAuth({
    scopes: 'https://www.googleapis.com/auth/cloud-platform'
  });
  const client = await auth.getClient();
  const projectId = await auth.getProjectId();
  // List all buckets in a project.
  const url = `https://storage.googleapis.com/storage/v1/b?project=${projectId}`;
  const res = await client.request({ url });
  console.log(res.data);
}
<pre class="typing-tooltip"><code data-language="javascript" class="language-javascript"><span class="token keyword">function</span> <span class="token function">main</span><span class="token punctuation">(</span><span class="token punctuation">)</span><span class="token operator">:</span> <span class="token builtin">Promise</span><span class="token operator">&lt;</span><span class="token keyword">void</span><span class="token operator">></span></code></pre>

const {ExternalAccountClient} = require('google-auth-library');
const jsonConfig = require('/path/to/config.json');

async function main() {
  const client = ExternalAccountClient.fromJSON(jsonConfig);
  client.scopes = ['https://www.googleapis.com/auth/cloud-platform'];
  // List all buckets in a project.
  const url = `https://storage.googleapis.com/storage/v1/b?project=${projectId}`;
  const res = await client.request({url});
  console.log(res.data);
}
<pre class="typing-tooltip"><code data-language="javascript" class="language-javascript"><span class="token punctuation">(</span>alias<span class="token punctuation">)</span> <span class="token keyword">class</span> <span class="token class-name">ExternalAccountClient</span>
<span class="token keyword">import</span> ExternalAccountClient</code><div class="typing-tooltip-markup">Dummy class with no constructor. Developers are expected to use fromJSON.</div></pre>

const {ExternalAccountClient} = require('google-auth-library');
const jsonConfig = require('/path/to/config.json');

async function main() {
  const client = ExternalAccountClient.fromJSON(jsonConfig);
  client.scopes = ['https://www.googleapis.com/auth/cloud-platform'];
  // List all buckets in a project.
  const url = `https://storage.googleapis.com/storage/v1/b?project=${projectId}`;
  const res = await client.request({url});
  console.log(res.data);
}
<pre class="typing-tooltip"><code data-language="javascript" class="language-javascript"><span class="token punctuation">(</span>alias<span class="token punctuation">)</span> <span class="token keyword">class</span> <span class="token class-name">ExternalAccountClient</span>
<span class="token keyword">import</span> ExternalAccountClient</code><div class="typing-tooltip-markup">Dummy class with no constructor. Developers are expected to use fromJSON.</div></pre>

const {GoogleAuth} = require('google-auth-library');

/**
* Instead of specifying the type of client you'd like to use (JWT, OAuth2, etc)
* this library will automatically choose the right client based on the environment.
*/
async function main() {
  const auth = new GoogleAuth({
    scopes: 'https://www.googleapis.com/auth/cloud-platform'
  });
  const client = await auth.getClient();
  const projectId = await auth.getProjectId();
  const url = `https://dns.googleapis.com/dns/v1/projects/${projectId}`;
  const res = await client.request({ url });
  console.log(res.data);
}

main().catch(console.error);
<pre class="typing-tooltip"><code data-language="javascript" class="language-javascript"><span class="token punctuation">(</span>alias<span class="token punctuation">)</span> <span class="token keyword">class</span> <span class="token class-name">GoogleAuth</span>
<span class="token keyword">import</span> GoogleAuth</code></pre>

async function main() {
  const auth = new GoogleAuth({
    scopes: 'https://www.googleapis.com/auth/cloud-platform'
  });
  const client = await auth.getClient();
  const projectId = await auth.getProjectId();
  // List all buckets in a project.
  const url = `https://storage.googleapis.com/storage/v1/b?project=${projectId}`;
  const res = await client.request({ url });
  console.log(res.data);
}
<pre class="typing-tooltip"><code data-language="javascript" class="language-javascript"><span class="token keyword">function</span> <span class="token function">main</span><span class="token punctuation">(</span><span class="token punctuation">)</span><span class="token operator">:</span> <span class="token builtin">Promise</span><span class="token operator">&lt;</span><span class="token keyword">void</span><span class="token operator">></span></code></pre>

const {OAuth2Client} = require('google-auth-library');
const http = require('http');
const url = require('url');
const open = require('open');
const destroyer = require('server-destroy');

// Download your OAuth2 configuration from the Google
const keys = require('./oauth2.keys.json');

/**
* Start by acquiring a pre-authenticated oAuth2 client.
*/
async function main() {
  const oAuth2Client = await getAuthenticatedClient();
  // Make a simple request to the People API using our pre-authenticated client. The `request()` method
  // takes an GaxiosOptions object.  Visit https://github.com/JustinBeckwith/gaxios.
  const url = 'https://people.googleapis.com/v1/people/me?personFields=names';
  const res = await oAuth2Client.request({url});
  console.log(res.data);

  // After acquiring an access_token, you may want to check on the audience, expiration,
  // or original scopes requested.  You can do that with the `getTokenInfo` method.
  const tokenInfo = await oAuth2Client.getTokenInfo(
    oAuth2Client.credentials.access_token
  );
  console.log(tokenInfo);
}

/**
* Create a new OAuth2Client, and go through the OAuth2 content
* workflow.  Return the full client to the callback.
*/
function getAuthenticatedClient() {
  return new Promise((resolve, reject) => {
    // create an oAuth client to authorize the API call.  Secrets are kept in a `keys.json` file,
    // which should be downloaded from the Google Developers Console.
    const oAuth2Client = new OAuth2Client(
      keys.web.client_id,
      keys.web.client_secret,
      keys.web.redirect_uris[0]
    );

    // Generate the url that will be used for the consent dialog.
    const authorizeUrl = oAuth2Client.generateAuthUrl({
      access_type: 'offline',
      scope: 'https://www.googleapis.com/auth/userinfo.profile',
    });

    // Open an http server to accept the oauth callback. In this simple example, the
    // only request to our webserver is to /oauth2callback?code=<code>
    const server = http
      .createServer(async (req, res) => {
        try {
          if (req.url.indexOf('/oauth2callback') > -1) {
            // acquire the code from the querystring, and close the web server.
            const qs = new url.URL(req.url, 'http://localhost:3000')
              .searchParams;
            const code = qs.get('code');
            console.log(`Code is ${code}`);
            res.end('Authentication successful! Please return to the console.');
            server.destroy();

            // Now that we have the code, use that to acquire tokens.
            const r = await oAuth2Client.getToken(code);
            // Make sure to set the credentials on the OAuth2 client.
            oAuth2Client.setCredentials(r.tokens);
            console.info('Tokens acquired.');
            resolve(oAuth2Client);
          }
        } catch (e) {
          reject(e);
        }
      })
      .listen(3000, () => {
        // open the browser to the authorize url to start the workflow
        open(authorizeUrl, {wait: false}).then(cp => cp.unref());
      });
    destroyer(server);
  });
}

main().catch(console.error);
<pre class="typing-tooltip"><code data-language="javascript" class="language-javascript"><span class="token punctuation">(</span>alias<span class="token punctuation">)</span> <span class="token keyword">class</span> <span class="token class-name">OAuth2Client</span>
<span class="token keyword">import</span> OAuth2Client</code></pre>