title: Nestjs Swagger - Publishing different API docs on separate routes
body: <p>I am building an app that has public API and internal one. I would like to publish docs for these to different routes. I thought this would be accomplished by adding only certain tags to document (<code>addTag</code>) but after further reading and experiments it does not do the job.</p>
  
  <p>The docs always contain everything, all documented endpoints from all modules.</p>
  
  <p>Is this even possible? If so, how?</p>
  
  <p>I don't believe code is necessary but FWIW:</p>
  
  <pre class="lang-js prettyprint-override"><code>const pubOptions = new DocumentBuilder()
      .setTitle('Pub API Docs')
      .setDescription('Blah blah API documentation')
      .setVersion(p.version)
      .addBearerAuth()
      .addTag('public-app')
      .build();
  const document = SwaggerModule.createDocument(app, pubOptions);
  SwaggerModule.setup('public-api', app, document);
  
  const internalOptions = new DocumentBuilder()
      .setTitle('Internal API Docs')
      .setDescription('Blah blah API documentation')
      .setVersion(p.version)
      .addBearerAuth()
      .addTag('internal')
      .build();
  const iDocument = SwaggerModule.createDocument(app, internalOptions);
  SwaggerModule.setup('internal-api', app, iDocument);
  
  </code></pre>