How to filter (grep) output of a process in Procfile?

Question

I have a Procfile which looks like that:

electron: ./node_modules/.bin/electron .

I would like to remove all the lines whith _rawLocationToUILocation from the output. I've tried the following:

electron: sh -c './node_modules/.bin/electron . 2>&1 | grep -v rawLocationToUILocation'

but after that, all output is removed. I thought it could be linked to buffering so I used unbuffer but that did not change anything.

Any idea?

Answer 1

Found the answer myself. It was indeed related to buffering.

Using the --line-buffered option of grep resolved the problem.