logging - first pass

[mikeAdamss]

DEPENDS ON: ONSdigital/dp-python-tools#25

What is this

Add basic logging statements using the logger from dp-python-tools.

This will look a bit odd as its structure jsonlines but that;'s ok - this is the format requried for kibana and strcutured logging (which we will need down the line).

What to do

Sprinkle logging statments in.

Always start each function with some variation of an "I have started" function including the relvant variables.

Beyond that at any point we do a try catch either (a) log we succeeded with any relevant variables or (b) if we fail the try catch - log the problem before we send a notification.

The trick here is to think of it from the perspective of yourself if you were trying to debug unexpected behaviour in the pipeline.

Acceptance Criteria

• Logging statments added.

[martynspooner]

3pts