I applied online. I interviewed at bp (London, England) in Jan 2017
Interview
First you need to take the online assessment, then a phone interview, technical interview and assessment centre. The technical interview in my case were some simple coding problems where they wanted to look at your way of analysing a problem rather than whether you knew the language or not.
Interview questions [1]
Question 1
In the assessment centre they provide you with a case where you need to assess what is the best possible path the company should take