Config Server
config-server renders and serves runtime configuration selected by host,
service ID and environment tag. The Compose distributions normally publish it
on host port 8435 and mount Rust configuration through
LIGHT_RS_CONFIG_DIR.
Inputs
| Input | Purpose |
|---|---|
| Portal database connection | Reads configuration instance, property and snapshot projections. |
LIGHT_RS_CONFIG_DIR | Local startup and template directory. |
RUST_LOG | Logging filter. |
CONFIG_LOG_ANSI | ANSI log setting. |
| OAuth/JWKS configuration | Authenticates configuration clients. |
| Controller configuration | Registers the service and supports control-plane operations. |
Snapshot selection
Clients identify an exact tuple including host, service and environment. A snapshot for a similarly named host or service is not a fallback. Each client also supplies a Portal authorization identity whose claims must be valid for the requested instance.
Downloaded snapshots are commonly retained in a named config-cache volume.
The cache is part of startup resilience, but it can hide a publication mismatch
if an operator assumes a restart always fetches new configuration.
Change behavior
Configuration becomes active at service startup or through an explicit reload of a reloadable module. Copying a file into a cache directory does not itself activate it. For a failed publication, compare the selected snapshot ID, generation and source level with the value expected from Compose.