Turned on :error_handling, :underspecs, and :unmatched_returns in
mix.exs dialyzer config. The 97 warnings this surfaced were fixed in
place rather than suppressed:
- unmatched_return (79): explicit discard with `_ = ...` for
fire-and-forget side effects (Process.cancel_timer, :ets.new,
send/2), and pattern-matched `:ok = ...` for control-plane
Phoenix.PubSub subscribe/unsubscribe/broadcast calls so a future
return-shape change fails loud.
- contract_supertype (18): tightened @spec arg and return types on
data_builder, historical_loader, url_params, packet_utils,
encoding_utils, aprs_symbol, weather_controller, packet_replay to
match each function's actual success typing.
No behavioural change. mix compile clean, 1008 tests pass, dialyzer
count is now 0.
Replace case/cond/if blocks with multi-clause function dispatch
and pattern matching in function heads across 9 modules:
- WeatherUnits: case to multi-clause unit_system/1, unit_labels via do_unit_labels/1
- PacketUtils: if to pattern match on %{"id" => id}, multi-clause threshold/callsign
- SetLocale: case to multi-clause extract_locale/1
- IPGeolocation: if/cond to pattern match on conn, binary prefix matching for private_ip?
- DeviceIdentification: cond to extracted pattern_matches?/2
- MobileChannel: cond to multi-clause do_callsign_match/2
- PacketProcessor: cond to dispatch_visibility/6 on {in_bounds, has_marker} tuple
- PacketManager: destructure packet_state in heads, multi-clause maybe_cleanup/3
- AprsSymbol: case/if to multi-clause get_table_id/1, normalize_symbol_code/1
This commit introduces a dual-mode caching and rate limiting system that can use
either Redis (for distributed deployments) or ETS/Cachex (for single-node setups).
Key changes:
- Add Cache abstraction layer that automatically switches between Redis and Cachex
- Implement RedisCache module with full distributed cache functionality
- Implement RedisRateLimiter with sliding window algorithm for accurate rate limiting
- Add RateLimiterWrapper to provide unified API for both implementations
- Update application startup to conditionally use Redis when REDIS_URL is set
- Migrate all cache operations to use the new Cache abstraction
- Support graceful fallback to ETS-based solutions when Redis is unavailable
The system automatically detects Redis availability via REDIS_URL environment
variable and switches between implementations without code changes. This enables
proper distributed caching and rate limiting in Kubernetes deployments while
maintaining backward compatibility for development environments.
🤖 Generated with [Claude Code](https://claude.ai/code)
Co-Authored-By: Claude <noreply@anthropic.com>
