geocode-city-api

Deployment

I personally use the Heroku Container Registry. For this repository, pushes to the main branch will automatically deploy to Heroku. To manually generate a Docker image and load it locally, you can run:

docker load < $(nix-build ./nix/docker.nix)

NOTE: the above requires a linux environment. On my Mac, I use linuxkit.

Datastores

In heroku, I use the hobby-dev Postgres add-on, and the free redis addon. One thing to note, is that for the hyperloglog entries to "fall off" as we reach max memory, I'm using the allkeys-lru eviction policy, set with:

heroku redis:maxmemory REDIS-NAME --policy allkeys-lru -a geocode-city

Database migrations (Heroku specific)

I should set up a release phase to run migrations automatically. However, I'd rather not have that overhead for something that happens somewhat seldom, so I instead use a one-off dyno:

> heroku run bash -a geocode-city
Running bash on ⬢ geocode-city... up, run.7528 (Hobby)
~ $ pwd
/opt/geocode-city-api
~ $ ls
geocode-city-api-exe  migrations
~ $ ./geocode-city-api-exe --migrate
Initializing schema
NOTICE:  relation "schema_migrations" already exists, skipping
Ok:	202101182025_geonames_raw.sql
Ok:	202101182130_non_city_tables.sql
Ok:	202101182140_city_table.sql
Ok:	202101182150_ft_and_indexes.sql
Ok:	202101191900_api_keys_table.sql
Ok:	202101201800_materialize_autocomplete.sql
Ok:	202101231600_api_quotas.sql
Execute:	202101301530_full_text_autocomplete.sql
All migrations ran.

Development

To provide repeatable builds, I use nix. To build the executable, you can either enter a nix-shell, which provides a development environment (cabal and haskell-language-server are included,) or build the project with nix-build ./nix/release.nix.

Execute

• Run nix-shell --run 'cabal new-run' to run the server with the default config (see Config.hs). You can override with environment vars: PORT and DATABASE_URL.
• Run nix-shell --run 'geocode-city-api-exe --migrate' to run any pending migrations. We endeavor to write idempotent migrations, so running it shouldn't affect an existing schema.

Run tests

nix-shell --run 'cabal test'