Containerize new back end

[akittredge]

In spring 2025, Carto finally discontinued its Legacy product. Boundaries Map relied on Legacy Carto for its back end. The back end consisted of a single table of all boundaries which could be queried by API.

The replacement back end is a PostgreSQL + PostGIS database with a Flask API running on an EC2 instance. The functionality is largely the same, with a few minor improvements:

• The SQL commands are defined on the server side, rather than being passed via the Legacy Carto API URL:
  • https://bm-api.beta.nyc/bounds_new?id=cd
  • https://bm-api.beta.nyc/district_int_new?boundid=cc&featureid=1
• All district intersections are pre-computed and stored in their own table
• Boundaries are simplified using ST_SimplifyPreserveTopology with a threshold of 0.00001˚ (approximately one quarter of the width of a major NYC street)

Additionally, all boundaries have been updated using Nathan Storey's improved methodology.

The next major improvement to this repo will include the new back end setup.