Abacus Express wrapper falsely emits listen success

[ghost]

Hi,

In abacus-express we override the listen function of express. However, when we perform an server.listen operation, we never check for an error, hence we always emit a successful start, which may not be the case if, for example, the port is in use.

As you can see below, we ignore any errors in the callback.

https://github.com/cloudfoundry-incubator/cf-abacus/blob/0597f7fbe5de1387389c2c5de8ac4ca27237736b/lib/utils/express/src/index.js#L598-L607

[cf-gitbot]

We have created an issue in Pivotal Tracker to manage this:

https://www.pivotaltracker.com/story/show/151434176

The labels on this github issue will be updated when the story is started.