compose-mysql-helloworld-nodejs overview

compose-mysql-helloworld-nodejs is a sample IBM Cloud application which shows you how to connect to an IBM Compose for MySQL for IBM Cloud service using Node.js.

Running the app on IBM Cloud

1. If you do not already have an IBM Cloud account, sign up here

2. Download and install IBM Cloud CLI.

The IBM Cloud CLI tool tool is what you'll use to communicate with IBM Cloud from your terminal or command line.

3. Connect to IBM Cloud in the command line tool and follow the prompts to log in.

bx login

Note: If you have a federated user ID, use the bx login --sso command to log in with your single sign on ID.

4. Make sure you are targeting the correct IBM Cloud org and space.

bx target --cf

Choose from the options provided. If you have already created the service, use the same options here as you used when creating the service.

5. Create your service.

If you don't already have a Compose for MySQL service in IBM Cloud, you can create one now using the create-service command.

Note : The Compose for MySQL service does not offer a free plan. For details of pricing, see the Pricing page of the Compose for MySQL documentation.

You will need to specify the service plan that your service will use, which can be Standard or Enterprise. This readme file assumes that you will use the Standard plan. To use the Enterprise plan you will need to create an instance of the Compose Enterprise service first. Compose Enterprise is a service which provides a private isolated cluster for your Compose databases. For information on Compose Enterprise and how to provision your app into a Compose Enterprise cluster, see the Compose Enterprise for IBM Cloud help.

To create your service, use the create-service command, specifying the service identifier, compose-for-mysql, the service plan and a name for your new service instance. For example, to create a service called "my-compose-for-mysql-service" on the Standard plan, the command would be:

bx cf create-service compose-for-mysql Standard my-compose-for-mysql-service

The actual provisioning of the service can take a few minutes, so while that's happening you can clone the sample app, update it so it is ready to be bound to your service, and push the app to IBM Cloud.

6. Clone the app to your local environment from your terminal using the following command:

git clone https://github.com/IBM-Cloud/compose-mysql-helloworld-nodejs.git

7. cd into this newly created directory. The code for connecting to the service, and reading from and updating the database can be found in server.js. See Code Structure and the code comments for information on the app's functions. There's also a public directory, which contains the html, style sheets and javascript for the web app. For now, the only file you need to update is the application manifest.

8. Update the manifest.yml file.

• Change the host value to something unique. The host you choose will determinate the subdomain of your application's URL: <host>.mybluemix.net.
• Change the name value. The value you choose will be the name of the app as it appears in your IBM Cloud dashboard.

Update the service value in manifest.yml to match the name of your service.

9. Push the app to IBM Cloud. When you push the app it will automatically be bound to the service.

bx cf push

Your application is now running at <host>.mybluemix.net.

The node-mysql-helloworld app displays the contents of an examples database. To demonstrate that the app is connected to your service, add some words to the database. The words are displayed as you add them, with the most recently added words displayed first.

Code Structure

File	Description
server.js	Establishes a connection to the MySQL database using credentials from VCAP_ENV and handles create and read operations on the database.
main.js	Handles user input for a PUT command and parses the results of a GET command to output the contents of the MySQL database.

The app uses a PUT and a GET operation:

• PUT

  • takes user input from main.js
  • uses the connection.query method to add the user input to the words table

• GET

  • uses connection.query method to retrieve the contents of the words table
  • returns the response of the database command to main.js