For ASP .NET developers, there are a few terms and technologies that need defining. As with any new technology stack, there is a learning curve involved. We’ll be using the following technologies in this Node.js Heroku tutorial:
Jade: A template engine for writing the views for our node.js MVC web application. Jade is similar to Razor in MVC ASP .NET, but with different formatting. Jade provides simplified HTML coding and allows omitting closing tags through the use of tabs for indentation (to mark begin/end blocks in HTML code).
Heroku: A cloud-based application platform for hosting web applications that were developed in a variety of languages. Heroku provides hosting for web apps written in Ruby, Java, Python, Scala, and of course, Node.js. One of the most appealing features of Heroku is its open-source friendliness with its free-plan pricing structure.
Git: A versioning system for keeping track of file changes. Similar to SVN (and TFS, with respect that they’re both version control systems), Git allows pushing and pulling code from and to local or remote repositories. A local repository can be created in a simple folder in Windows. Any folder can have its own repository. Git also supports remote repositories. Heroku provides a Git repository that you can commit to. GitHub and BitBucket also provide Git repositories for online storage of code.
Before we get started, we’ll need to install the required software for creating a node.js web application, committing to a Git repository, and working with Heroku. We’ll start with Git.
Install Git, the server software
Install a Git client (for creating repositories, committing files, and working with Git). I recommend using Tortoise Git for Windows
Create an account on Heroku, for hosting your node.js app
Install the Heroku tools, for creating projects, hosting, and configuring
Open a command prompt in Windows with administrator access (type cmd, right-click the result and select Run As Administrator).
At the command prompt, type: npm login
Enter your Heroku account email address and password.
This will log you into the Heroku toolkit so that you can publish your files to the server.
With the tools installed, we’ll now need to configure Heroku with an SSH key for publishing our files. First, we’ll generate a key and then we’ll add it to our Heroku account.
Run Puttygen in Windows (installed with Git). You can do this by clicking Start and typing: puttygen
In Puttygen, click the Generate button to create an SSH key.
Click Save Private Key and choose Yes when prompted if you wish to save the key without a password (you can choose to enter a password, if you wish, but for the sake of simplicity with this tutorial, we’ll choose not to create one).
Save the file as heroku_key.ppk to any folder of your choice.
Copy the key text from the textbox, paste it into Notepad, and save it to C:\Users[username].ssh\id_rsa.pub (if a file already exists, overwrite it).
Run Pageant in Windows (installed with Git). You can do this by clicking Start and typing: pageant
Right-click the pageant icon in the system tray next to your clock and click Add Key.
Select heroku_key.ppk that you saved in step 4 above and click Open.
At the Windows command prompt, type: heroku keys:add (this will let you add the key to your Heroku account)
At the Windows command prompt, type: heroku create (this will make a new app url). Copy the git: url in the output and save it for later. You’ll need this in order to save your files into your repository for publishing. If you forget the url, you can find it in your Heroku account, online.
In Windows, create a folder for your code files.
At the Windows command prompt, navigate to the folder you created in step 11.
Type: npm install express jade stylus (this will install the Express, Jade, and Stylus libraries for node.js)
With our tools installed and our working environment created, we can begin writing our first node.js code file. In Windows, open the folder you created in step 11 above and create a new file named “helloworld.js”. Type the following code into the file:
The above code uses the Express framework to simplify our node.js web application code. We first reference the required api (Express). We then establish a route to the root url /. When a user accesses the root url, we’ll print the text “Hello World!” to the web browser. The final block of code tells the Node.js web server to listen on a configured port for incoming connections to our web application.
In Windows, open a command prompt, navigate to your project folder, and type: node helloworld
This should begin running your helloworld.js web application.
Open a web browser and navigate to http://localhost:3000
You should see your web applicaiton running, displaying the text “Hello World!”.
We’ve successfully ran our node.js web application locally and loaded the page in our web browser. Now it’s time to publish the code to our Heroku server for the world to see. We’ll first need to create two configuration files for Heroku, as follows:
- Create a file in your project folder, named package.json with the following contents:
- Create a file named Procfile. It must contain a capital ‘P’. In Windows, you can first save a file from Notepad as “procfile.txt” then rename it to “Procfile” in the Windows Explorer. It should have the following contents:
web: node helloworld.js
Test Heroku locally, by opening a command prompt with Administrator access, navigate to your app’s folder, and type: foreman start
Open a web browser and navigate to http://localhost:5000
You should be able to see your web application running, displaying the text “Hello World!”
With Heroku setup locally and our code ready to deploy, it’s time to commit our code to a Git repository and publish it live. We can do this as follows:
Create a new Git repository in your app folder by right-clicking the folder in Windows and selecting Git Clone.
In the Git clone dialog, for the field “URL:”, paste the Git url that you copied from Step 10 above under “Setting up Heroku”. Click OK to clone the repository.
Move the files that you created for the project into the new Git folder.
Navigate into the new folder.
Create a new text file named .gitignore with the following contents:
Right-click in the folder and click Git Commit -> master.
Enter a description for the message, checkmark all files (.gitignore, Procfile, helloworld.js, package.json), and click OK.
To publish to Heroku, right-click the folder again and select TortoiseGit->Push. Under “Destination”, select “Remote“ and verify the drop-down is set to “origin“ (which points to Heroku). Alternatively, you could edit the field “Arbitrary URL” and paste the Git url that you created earlier in this article). Click OK to commit.
Open a Windows command prompt and navigate to your project’s Git folder. Then type: heroku ps:scale web=1
Your node.js web application should now be running live! Navigate to your app’s url (you can find it in your heroku account on the web site)
Create a Cloud9 account
On your dashboard, click the “Show your SSH key“ link, along the right-side.
Copy the SSH key text and paste it into Notepad. Save the file as C:\Users[username].ssh\cloud9.pub
Open a command prompt in Windows and type: heroku keys:add
Select the file cloud9.pub that you saved from step 3 above.
In Cloud9, click Create New Workspace and choose Clone From Url.
Paste the Git url for your Heroku project (you can find it in your Heroku account, under My Apps).
Click Start Editing.
At the Cloud9 command prompt, type: npm install express
Double-click helloworld.js and modify the text for “Hello World!”, such as changing it to “Hello World, modified by Cloud9 IDE”.
Click the Run icon and double-click the .js file to run. You can then browse to the Cloud9 debug url to see it in action.
Click Stop to end debugging.
To commit the changes, at the Cloud9 command prompt type: git commit -m -a
Then type: git push
This article was written by Kory Becker, software developer and architect, skilled in a range of technologies, including web application development, machine learning, artificial intelligence, and data science.rs.