bst_date is a date field. Comparing dates with datetimes in postgres
gets confusing and dangerous. See this example, where a date evaluates
as older than midnight that same day.
```
notification_api=# select '2019-04-01' >= '2019-04-01 00:00';
?column?
----------
f
(1 row)
```
By only using dates everywhere, we reduce the chance of these bugs
happening
This is still a work in progress but it would be good to get some eyes on it.
This commit includes creating and updating a row in the monthly billing table and a method to fetch the results.
There is a command to populate the monthly billing for a service and month so we can try it out.
The total cost at the moment are wrong, they do not take into account the free allowance - see notes below about adding that to the table.
Left to do:
create a nightly task to run to update the monthly totals.
create an endpoint to return the yearly billing, the current day will need to be calculated on the fly and added to the totals.
Add the free allowance into the total costs.
Once we have the new columns in notifications table, the query will need to include the rate multiplier and if the number is international.
The monthly billing query will be built next.
