How to implement EventSource on Codeignigter app?

SO how would I do this?

First, you have to convince me that EventSource is really the right solution. 

Answering the question, "How long does this process take?" would be a good start toward convincing me it is.

It can take anywhere between 3 minutes to 3 hours, depending on the items being processed. Should I turn to websockets instead? What would you recommend?