superman-detector

Considerations/Improvements

An openapi spec is provided to generate client libraries against the API. Ideally behavioral/integration level tests would be added and run against a running API. Tests should also be validating the response structure that is in the expected format in openapi.
Abstracting out the ORM. Gorm was used to communicate to the database and while this is passed via composition to the login handler, the queries are highly coupled to GORM. This should be abstracted out further, since a true dev/prod environment would be using different RDBS (Postgres, Mysql) or NoSql alternatives (Dynamo, Datastore).
Radius uncertainty, was not implemented but would have most likely added additional field related to Propagation of Error.
Caching, although the application is measuring the percentile performance of runtime geo ip lookups and travel distance. These could be possibly be cached using memoization(increased memory usage) or a caching layer LRU (redis). GeoIP rows could also have been inserted into an already created sqlite database as well.
Pprof could be added with an auth middleware protecting the route or a profiling library such as Stackdriver Profiler.

Running

As 12 Factor suggests configuration should be stored in the environment. For local purposes and running in an orchestrator setting sensitive information can be provided in other manners (volumeMounts, secrets (k8, aws ssm, aws sm), etc). Below are settings that configure the runtime and defaults.

Environment Variable Settings/Lookup

DETECTOR_API_SERVER_READ_TIMEOUT_SECONDS=5s
DETECTOR_API_SERVER_WRITE_TIMEOUT_SECONDS=10s
DETECTOR_API_SERVICE_PORT=8080
DETECTOR_API_SPEED_THRESHOLD_MILES_PER_HOUR=500
DETECTOR_API_GEO_IP_DATABASE_FILE_LOCATION=./GeoLite2-City.mmdb
DETECTOR_API_STASTD_NAMESPACE=superman-detector
DETECTOR_API_STATSD_ADDRESS=localhost:8125
DETECTOR_API_STATSD_BUFFER_POOL_SIZE=1000
DETECTOR_API_SQL_DIALECT=sqlite3
DETECTOR_API_SQLC_CONNECTION_STRING=/tmp/superman.db

Running executable/binary

make superman-detector && ./superman-detector

Running in docker

make build.docker && docker run -d superman-detector

Running in docker-compose api w/ telemetry

docker-compose up

Metrics

Application metrics are send via statsd over UDP. Docker-compose is setup to have a telegraf sidecar listening for statsd with tag support. Outputs are available as a stream, and Prometheus scraping /metrics.

Tests

make test

External Libraries

Resources/References

Go 1.13
Goland IDE (gofmt, govet, golangci-lint)
Docker 19.03.5
Docker-Compose 1.24.1
Influxdata Telegraf 1.13.2

jrxFive/superman-detector