Client package: django-udp-discovery-client

Role

django-udp-discovery-client implements the UDP broadcast side of the toolkit: enumerate interfaces, send the discovery payload, collect SERVER_IP: replies, and present structured DiscoveryResult objects. Django is optional; only discovery_client_django needs it.

Install paths

pip install django-udp-discovery-client                  # core only
pip install "django-udp-discovery-client[network]"       # recommended
pip install "django-udp-discovery-client[all]"          # network + django extras

[network] installs netifaces / ifaddr so discover() can broadcast per interface. Without it, discover() logs an ImportError and returns [].

Public API (discovery_client)

__all__ exports:

  • ClientConfig — dataclass with validation + from_env.

  • load_config(**kwargs) — merges defaults, DISCOVERY_CLIENT_* env vars, then kwargs.

  • DiscoveryResult — ip, port, raw_response, extra.

  • discover(config=None) → list[DiscoveryResult] — never raises for network errors; returns empty list and logs.

  • discover_one(config=None) → first result or None.

Environment variables (prefix DISCOVERY_CLIENT_)

PORT, MESSAGE, RESPONSE_PREFIX, TIMEOUT, RETRIES (stored but unused), ENABLE_SUBNET_SCAN (unused), INTERFACES_WHITELIST, INTERFACES_BLACKLIST (comma-separated names, case-sensitive).

discovery_client.network

Helpers for interface discovery and math:

  • get_interfaces(), select_interfaces(config), InterfaceInfo.

  • Netmask / broadcast utilities: netmask_to_prefix, broadcast_from_ip_and_mask, etc.

These power multi-interface broadcast selection and optional diagnostics when no servers answer.

Django integration

Add discovery_client_django to INSTALLED_APPS and run:

python manage.py discover_servers [--timeout ...] [--port ...] [--verbose]

The command builds a ClientConfig from CLI flags, calls discover(), prints a table, and emits the segmented network warning (via format_segmented_network_warning) when applicable and no hosts were found.

Behavioural notes you should know

  • Default HTTP port in results: if the server reply is only SERVER_IP:x.y.z.w (as the stock server sends), the client parser assumes port 8000 for convenience.

  • IPv4 / broadcast only: no IPv6; no multicast; broadcasts do not cross arbitrary routers/VLANs.

  • Blocking calls: plan thread boundaries accordingly.

  • Retries flag: present in config but not consumed by the socket layer today.

Further reading: django-udp-discovery-client modules.