When done, bit.ly/1gukTyn.

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Stretch Goals

Learn about partials and use them to implement the project thumbnail and jumbotron HTML in index.handlebars and project.handlebars

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Links

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Terminal

$ bash lab4/check-setup.sh

Debug

I got the error 

bash: lab4/check-setup.sh: No such file or directory

Make sure you're in your 'introHCI' directory and that you've cloned lab4 here.

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Terminal

$ bash lab4/check-setup.sh

Debug

What's the vagrant password?

vagrant

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Terminal

$ node app.js
Express server listening on port 3000

Debug

When I try to run node app.js I get a bunch of error messages, including the line 

Error: listen EADDRINUSE

This probably happened because Node crashed. For instance, Vagrant might have disconnected you all of a sudden.
To fix this problem, tell your browser to refresh http://localhost:3000 until you get "No data received" or a similar message. Now try starting Node again. Everything should be fine.

Explanation: The message EADDRINUSE means that Node can't start listening on port 3000 because it's already in use. The problem is that the last instance of Node failed to properly release port 3000 when it crashed. By refreshing the webpage, we're getting the OS to realize 'Oh, the Node server isn't using port 3000 anymore' and consequently release it.

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Links

Debug

I get a blank page!

Make sure node is running (see previous slide).

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Code

    <div class="project" id="{{id}}">
      <a href="project" class="thumbnail">
        <img src="images/{{image}}" class="img">
        <p>{{name}}</p>
      </a>
    </div>

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Video

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Code

exports.view = function(req, res){
  res.render('index', {
    'name': 'Waiting in Line',
    'image': 'lorempixel.people.1.jpeg',
    'id': 'project1'
  });
};

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Links

Debug

My images didn't load!

Restart node, see slide 31.

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Code

  res.render('index', {
    'projects': [
      { 'name': 'Waiting in Line',
        'image': 'lorempixel.people.1.jpeg',
        'id': 'project1'
      },
      { 'name': 'Needfinding',
        'image': 'lorempixel.city.1.jpeg',
        'id': 'project2'
      },
      { 'name': 'Prototyping',
        'image': 'lorempixel.technics.1.jpeg',
        'id': 'project3'
      },
      { 'name': 'Heuristic Evaluation',
        'image': 'lorempixel.abstract.1.jpeg',
        'id': 'project4'
      },
      { 'name': 'Visualization',
        'image': 'lorempixel.abstract.8.jpeg',
        'id': 'project5'
      },
      { 'name': 'Social design',
        'image': 'lorempixel.people.2.jpeg',
        'id': 'project6'
      },
      { 'name': 'Gestural interaction',
        'image': 'lorempixel.technics.2.jpeg',
        'id': 'project7'
      },
      { 'name': 'Design tools',
        'image': 'lorempixel.city.2.jpeg',
        'id': 'project8'
      }
    ]
  });

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Solution

    {{#each projects}}
      <div class="project" id="{{id}}">
        <a href="project" class="thumbnail">
          <img src="images/{{image}}" ... />
          <p>{{name}}</p>
        </a>
      </div>
    {{/each}}

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Links

Debug

My page didn't change!

Restart node, see slide 31.

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Add a table of contents

    <ol>
    {{#each projects}}
      <li><a href="#{{id}}">{{name}}</a></li>
    {{/each}}
    </ol>

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Links

Debug

The list doesn't appear.

Restart node, see slide 31.

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Add app.js route

...

var index = require('./routes/index');
var project = require('./routes/project');
// Example route
...

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Route URL to controller

...
// Add routes here
app.get('/', index.view);
app.get('/project', project.viewProject);
// Example route
...

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Code

exports.viewProject = function(req, res) {

  // controller code goes here

};

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Code

  res.render('project');

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Links

Debug

“Error: .get() requires callback functions but got a [object Undefined]”

It couldn’t find the right controller function. The route is wrong or project.js is named incorrectly.

When I click on the project, my browser responds 'Cannot GET /project.html'

Notice that we added the route '/project' not '/project.html'. Your views/index.handlebars file probably has <a href="project.html" ... >. Just change it to <a href="project" ... >.
Reminder: You need to explicitly refresh localhost:3000 in order to see the change.

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Route URL to controller

app.get('/project/:name', project.viewProject);

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Code

  var name = req.params.name;

  console.log("The project name is: " + name);

Links

Debug

When I click on the project, I just get 'Cannot GET /project' again!

yes, again the problem is that we haven't fixed views/index.handlebars yet. However, you can type localhost:3000/project/foo directly into your address bar to test the route we just added.

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Code

  res.render('project', {
    'projectName': name
  });

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Code

    <div class="jumbotron">
      <h1>{{projectName}}</h1>
      <p>one-sentence description of project</p>
    </div>

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Code

    {{#each projects}}
      <div class="project" id="{{id}}">
        <a href="project/{{name}}" class="thumbnail">
          <img src="images/{{image}}" ... />
          <p>{{name}}</p>
        </a>
      </div>
    {{/each}}

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Video

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GitHub - Commit

git status
git add ...
git commit -m "node.js lab"

Github - Push

git push

Heroku - Create

heroku create newapplicationname

Heroku - Push

git push heroku master

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Links

When done, submit at http://hci.st/lab-submit.