support credit refunds in billing report

[shaneknapp]

i sure do wish there was a better way to do this, other than scanning for a text pattern in a field... apparently there's no documented code i can find right now that will do this.

i won't merge until after i spend more time digging to see if there's a better way. :\

[jey]

meh, looks pretty reasonable to me. maybe you can parse the row objects into a namedtuple to make the code easier to read?

i think the official field names are available here: https://docs.aws.amazon.com/awsaccountbilling/latest/aboutv2/enhanced-lineitem-columns.html

[jey]

'Unauthorized Usage' in row[18]

might want to use a stricter test than just a substring check, since it's better for the script to error out if the format of the field changes, which serves as a notice to update the code for the new changes

[shaneknapp]

re: namedtuple... sure thing.

re: list of lineitem types... i found that exact page, but none of those fields actually show up in the detailed billing report. hence my sad 'Unauthorized Usage' in row[18] hack. :(

re: stricter parsing, sounds good to me.

[jey]

Hm, the way I'm reading it, I think that row[18] should be the 19th entry on that page, which is "lineItem/UsageType"? So with the namedtuple maybe it would end up looking like row.usage_type.startswith("Unauthorized Usage")?

[shaneknapp]

btw i haven't forgotten about this... more commits coming this week.