openapi.yaml file incorrectly specifies type for before and after parameters

[jonquandt]

What kind of issue?

• Feature Request?
• Bug

User story

Please provide us with a description of the issue as a user story
As a analytics API user, I would like to be able to use the openapi.yml file in postman, so that I can do more detailed analysis of analytics.usa.gov data.

Acceptance Criteria

• before and after parameters should be specified as type: string, format:date -- currently they are type:integer, which causes failures when trying to follow the YYYY-MM-DD format specified in the parameter description

Notes

• I arrived at this issue tracker via https://open.gsa.gov/api/dap/, but I don't see the openapi.yaml file referenced here within this repo, so sorry if putting in the wrong spot.
• it looks like the yaml may be generated from annotations within the code

Tasks (Optional)