autocompleted

A tag autocomplete API service for Fennec, written in Rust using actix-web. It queries a PostgreSQL database for matching tags and caches results in memory. Used for GayFurCity.

Endpoints

Method	Path	Description
GET	/	Autocomplete tags
GET	/up	Health check (returns 204)

Prometheus metrics are served separately, on METRICS_ADDR, so /metrics is never reachable through the public reverse proxy:

Method	Path	Description
GET	/metrics	Prometheus metrics (on METRICS_ADDR, not SERVER_ADDR)

Exposes standard actix-web-prom HTTP metrics (autocompleted_http_requests_total, autocompleted_http_requests_duration_seconds) plus:

• autocompleted_cache_hits_total / autocompleted_cache_misses_total — in-memory cache effectiveness
• autocompleted_db_query_duration_seconds — tag lookup query latency

GET /?search[name_matches]=<prefix>

Returns a JSON array of matching tags. The prefix must be 3–100 characters.

Example:

GET /?search[name_matches]=cani

Response:

[
  {"id": 1, "name": "canine", "post_count": 12345, "category_id": 0, "antecedent_name": null}
]

Responses are cached for 6 hours (up to 15,000 entries). Supports * as a wildcard in the prefix.

Configuration

Copy .env.sample to .env and fill in the values:

SERVER_ADDR=0.0.0.0:3000
METRICS_ADDR=0.0.0.0:9396
PG__USER=postgres
PG__PASSWORD=secret
PG__HOST=localhost
PG__PORT=5432
PG__DBNAME=mydb
PG__POOL__MAX_SIZE=16

Running

# Development
cargo run

# Docker
docker compose up

Building

cargo build --release

License

See LICENSE.