Overview

This used to be part of the NodeRoutesBasics assignment but now can be safely ignore.

More Complex Example

This does not directly relate to the current assignment, but I’m leaving it here for now. It still has jQuery code in it, so it is old fashioned, bordering on obsolete. You can ignore this entire section.

Now an example showing how to call a route with parameters:

function callServerWithParms() {

	// Get Data We Want to Pass to the Server
	var dirsToWalk = document.getElementById('dirsToWalk');
	var directory = dirsToWalk.options[sourceIndex].value;
	var destinationDirs = document.getElementById('destinationDirs');
	var destinationDir = destinationDirs.options[destinationIndex].value;

	var highlight = $('#highlight').prop('checked');

	// Put that data in JavaScript Object
	var requestQuery = {
		directoryToWalk: directory,
		destinationDir: destinationDir,
		highlight: highlight,
	};

	// Call the server and pass the data as a parameter.
	$.getJSON('/walk', requestQuery, function (result) {
		elf.display.showApacheFiles(result.htmlFilesWritten, result.destinationDir);
		elf.display.fillDisplayArea(JSON.stringify(result, null, 4));
	}).done(function () {
			elf.display.showDebug('Walk loaded second success');
		})
		.fail(function (jqxhr, textStatus, error) {
			elf.display.showDebug('Walk loaded error: ' + jqxhr.status + ' ' + textStatus + ' ' + error);
		})
		.always(function () {
			elf.display.showDebug('Walk loaded complete');
		});

}

Below, in the next section, we look more closely at passing parameters.

Client Server Interactions

Look at these code excerpts from the code shown above. We look specifically at the call to the server:


	// Put that data in JavaScript Object
	var requestQuery = {
		directoryToWalk: directory,
		destinationDir: destinationDir,
		highlight: highlight,
	};

	// Call the server and pass the data as a parameter.
	$.getJSON('/walk', requestQuery, function (result) { ... });

And here is what it looks like on the server. Notice how we use the request object to discover the parameters passed by the client:


router.get('/walk', function(request, response) {
    'use strict';
    console.log('In walk', request.query);
    var directoryToWalk = request.query.directoryToWalk;
    var destinationDir = request.query.destinationDir;
    var highlight = request.query.highlight;
    etc
});

Update Out of Date Packages

$ npm install -g npm-check-updates
$ ncu
$ ncu -u
$ npm install

Also, be sure to remove phantomjs from packages.json.

See here:

Setting up the Port

Let’s allways use the following:

var port = process.env.PORT || 30025;

// Code omitted here...

app.listen(port);
console.log('Listening on port :' + port);

We want to pick a particular port because in some situations, such as running on EC2, we need to open the port ahead of time. By choosing one port, and always using it, you won’t have to edit my code before you can run it, and vice versa.

Node Express Routing Basics

Express offers support for HTTP verbs such as Get, Post, Put, etc.

The verbs provide a response to specific routes, such as ‘/’:

app.get('/', function(req, res) {
    console.log("root request sent");
});

Or here is request that uses a wildcards or regular expressions:

app.get('/a*', function(req, res) {
    console.log("A request sent that begins with an a");
});

Working with numbers:

app.get('/book/:id((d+)', function(req, res) {
    console.log("Only requests that are numbers");
});

Node Express Serving up Static Pages

Put your static files in a particular directory and tell express about the directory:

app.use("/public", express.static(__dirname + '/public'));

Server them up like this:

app.get('/', function(req, res) {
    var html = fs.readFileSync('public/index.html');
    res.writeHeader(200, {"Content-Type": "text/html"});
    res.end(html);
});

Temp directory

This is optional. Skip if you are not interested.

Instead of running npm install and bower install, do this:

  • Copy a reasonably up to date version of node_modules from one of your projects to ~/tmp.
  • Copy a reasonably up to date version of public/components from one of your projects to ~/tmp.

For instance

mkdir ~/tmp
cp ~/Git/isit322-lastname-2016/Week04-Middleware/node_modules ~/tmp
cp ~/Git/isit322-lastname-2016/Week04-Middleware/public/components ~/tmp

You might want to also copy the package.json and bower.json files to tmp. As needed, update your files to the latest:

cd ~/tmp
npm outdated --depth=0

And then get the latest of everything as needed.

Now go back to your project and create symbolic links to these packages. The best way to do this is to use

  • the run alias from ~/.bash_aliases
  • or the nm and component aliases from ~/.bash_aliases.

Just as an fyi, here they are:

alias run="nm && components && npm start"
alias nm="ln -s ~/tmp/node_modules/"
alias components="ln -s ~/tmp/components/ public/components"

For this project, do the following in ~/tmp, or, if you have completed the above, in your project:

npm install supertest –save-dev npm install jasmine –save-dev npm install -g jasmine

NOTE: The point of setting up this ~/tmp directory is to put an end to long npm installs during class. Talk to Adam, he knows all about this.