freeCodeCamp/curriculum/challenges/espanol/06-quality-assurance/advanced-node-and-express/implement-the-serialization-of-a-passport-user.md

id	title	challengeType	forumTopicId	dashedName
5895f70cf9fc0f352b528e67	Implement the Serialization of a Passport User	2	301556	implement-the-serialization-of-a-passport-user

--description--

Right now, we're not loading an actual user object since we haven't set up our database. This can be done many different ways, but for our project we will connect to the database once when we start the server and keep a persistent connection for the full life-cycle of the app. To do this, add your database's connection string (for example: mongodb+srv://:@cluster0-jvwxi.mongodb.net/?retryWrites=true&w=majority) to the environment variable MONGO_URI. This is used in the connection.js file.

You can set up a free database on MongoDB Atlas.

Now we want to connect to our database then start listening for requests. The purpose of this is to not allow requests before our database is connected or if there is a database error. To accomplish this, you will want to encompass your serialization and your app routes in the following code:

myDB(async client => {
  const myDataBase = await client.db('database').collection('users');

  // Be sure to change the title
  app.route('/').get((req, res) => {
    //Change the response to render the Pug template
    res.render('pug', {
      title: 'Connected to Database',
      message: 'Please login'
    });
  });

  // Serialization and deserialization here...

  // Be sure to add this...
}).catch(e => {
  app.route('/').get((req, res) => {
    res.render('pug', { title: e, message: 'Unable to login' });
  });
});
// app.listen out here...

Be sure to uncomment the myDataBase code in deserializeUser, and edit your done(null, null) to include the doc.

Submit your page when you think you've got it right. If you're running into errors, you can check out the project completed up to this point here.

--hints--

Database connection should be present.

(getUserInput) =>
  $.get(getUserInput('url') + '/').then(
    (data) => {
      assert.match(
        data,
        /Connected to Database/gi,
        'You successfully connected to the database!'
      );
    },
    (xhr) => {
      throw new Error(xhr.statusText);
    }
  );

Deserialization should now be correctly using the DB and done(null, null) should be called with the doc.

(getUserInput) =>
  $.get(getUserInput('url') + '/_api/server.js').then(
    (data) => {
      assert.match(
        data,
        /null,\s*doc/gi,
        'The callback in deserializeUser of (null, null) should be altered to (null, doc)'
      );
    },
    (xhr) => {
      throw new Error(xhr.statusText);
    }
  );

--solutions--

/**
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*/