A simple Sinatra application. Once deployed to Cloud Foundry, it will echo the Environment and HTTP Request Headers.
This is especially useful to learn about service connection details ($VCAP_SERVICES) being passed to an application. Create them, bind them to this running application, and you'll see the nested JSON string that is set in $VCAP_SERVICES.
The repo contains a manifest file which creates a new application called cfenv, with a random string in the URL to avoid collisions.
To deploy:
$ cf push
Using manifest file manifest.yml
Creating cfenv... OK
Creating route cfenv-dfe2f.cfapps.io... OK
Binding cfenv-dfe2f.cfapps.io to cfenv... OK
Uploading cfenv... OK
Starting cfenv... OK
-----> Downloaded app package (64K)
-----> Using Ruby version: ruby-1.9.3
-----> Installing dependencies using Bundler version 1.3.2
Running: bundle install --without development:test --path vendor/bundle --binstubs vendor/bundle/bin --deployment
Fetching gem metadata from https://rubygems.org/..........
Fetching gem metadata from https://rubygems.org/..
Installing json_pure (1.8.0)
Installing rack (1.5.2)
Installing rack-protection (1.5.0)
Installing tilt (1.4.1)
Installing sinatra (1.4.3)
Using bundler (1.3.2)
Your bundle is complete! It was installed into ./vendor/bundle
Cleaning up the bundler cache.
-----> Uploading droplet (24M)
Checking cfenv...
Staging in progress...
Staging in progress...
Staging in progress...
1/1 instances: 1 running
OK
$ open http://cfenv-dfe2f.cfapps.io
To view a specific environment variable, you can use the /v1/:var endpoint:
$ curl http://cfenv-dfe2f.cfapps.io/v1/CF_INSTANCE_PORTS
[{"external":60148,"internal":8080},{"external":60149,"internal":2222}]
For envrionment variables that contain JSON data, you can grab individual values out of them as well (values are re-encoded to JSON):
$ curl http://cfenv-dfe2f.cfapps.io/v1/CF_INSTANCE_PORTS/0
{"external":60148,"internal":8080}
$ curl http://cfenv-dfe2f.cfapps.io/v1/CF_INSTANCE_PORTS/0/internal
8080
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