You can bind a data source to a Node.js application that is deployed and running on Cloud Foundry.
You must parse the VCAP_SERVICES
environment variable in your code to get the required connection details such as host address, port, user name, and password.
For example, if you are using PostgreSQL, your VCAP_SERVICES
environment variable might look something like this:
{
"mypostgres": [{
"name": "myinstance",
"credentials": {
"uri": "postgres://myusername:[email protected]:5432/serviceinstance"
}
}]
}
This example JSON is simplified; yours might contain additional properties.
The cfenv
package provides access to Cloud Foundry application environment settings by parsing all the relevant environment. The settings are returned as JavaScript objects. cfenv
provides reasonable defaults when running locally, as well as when running as a Cloud Foundry application.
For more information, see the npm website.
First, parse the VCAP_SERVICES
environment variable.
For example:
var vcap_services = JSON.parse(process.env.VCAP_SERVICES)
Then pull out the credential information required to connect to your service. Each service packages requires different information. If you are working with Postgres, for example, you need a uri
to connect. You can assign the value of the uri
to a variable as follows:
var uri = vcap_services.mypostgres[0].credentials.uri
Once assigned, you can use your credentials as you would normally in your program to connect to your database.
You must include the appropriate package for the type of services your application uses.
For example:
Edit package.json
and add the intended module to the dependencies
section. Normally, only one is necessary, but for the sake of the example, add all of them:
{
"name": "hello-node",
"version": "0.0.1",
"dependencies": {
"express": "*",
"mongodb": "*",
"mongoose": "*",
"mysql": "*",
"pg": "*",
"redis": "*",
"amqp": "*"
},
"engines": {
"node": "0.8.x"
}
}
You must run npm shrinkwrap
to regenerate your npm-shrinkwrap.json
file after you edit package.json
file.