Hot Reload

Filter pipelines are swapped atomically at runtime when the config file changes

Category: Setup-dependent integration
Task: Apply configuration changes without restarting

Prerequisites: Praxis runtime; A writable configuration file; An HTTP backend

Expected outcome: A valid file change replaces the active configuration while the process stays running.

This configuration comes from the selected release. The example has not been run here; external services are not bundled.

Download the source file.

# Hot Reload
#
# Filter pipelines are swapped atomically at runtime when the
# config file changes. In-flight requests complete on the old
# pipeline; new requests pick up the updated config.
#
# Usage:
#   cargo run -p praxis-proxy -- -c examples/configs/operations/hot-reload.yaml
#   curl http://localhost:8080/api/hello
#
#   Edit this file (e.g. change the static_response body)
#   and save. The next request reflects the change.
#
# What reloads dynamically:
#   - Filter pipeline configuration
#   - Router routes and path mappings
#   - Load balancer endpoints and weights
#   - Rate limit and circuit breaker settings
#   - Health check configuration
#
# What requires a restart:
#   - Listener add/remove/rebind
#   - Protocol changes (HTTP to TCP)
#   - Compression module addition
#   - TLS enable/disable

listeners:
  - name: gateway
    address: "0.0.0.0:8080"
    filter_chains:
      - routing
      - api

filter_chains:
  - name: routing
    filters:
      - filter: router
        routes:
          - path_prefix: "/api/"
            cluster: backend
          - path_prefix: "/health"
            cluster: backend
      - filter: load_balancer
        clusters:
          - name: backend
            endpoints:
              - "127.0.0.1:3000"
              - "127.0.0.1:3001"

  - name: api
    filters:
      - filter: request_id
      - filter: static_response
        status: 200
        body: '{"message": "hello from praxis"}'
        headers:
          - name: content-type
            value: "application/json"

insecure_options:
  allow_private_endpoints: true # example proxies to local backends