litefs.yml

# LiteFS production configuration for SettlerEngine
# This file manages SQLite database replication across multiple nodes.

# The directory where LiteFS mounts the FUSE file system.
# The SQLite database should reside within this directory to be replicated.
fuse:
  dir: "/litefs"

# The directory where LiteFS stores its internal state, transactional logs, and local databases.
# This directory should be backed by a persistent volume to preserve state across restarts.
data:
  dir: "/var/lib/litefs"

# The lease management configuration. This governs leader election for database writes.
# Only the leader (primary node) can write to the database; others are read-only replicas.
lease:
  type: "consul"
  
  # How other nodes can reach this node's internal API over private networking.
  advertise-url: "http://${HOSTNAME}.vm.${FLY_APP_NAME}.internal:20202"
  
  # If true, this node participates in leader elections.
  # Typically set dynamically so only nodes in the primary region can become candidates.
  candidate: ${FLY_REGION == PRIMARY_REGION}
  
  # Automatically promote this node to primary if no other primary is available.
  promote: true
  
  # Consul backend connection details (e.g., provided on Fly.io)
  consul:
    url: "${FLY_CONSUL_URL}"
    key: "litefs/${FLY_APP_NAME}"

# Intercept database HTTP traffic to auto-forward or handle write-routing in LiteFS proxy
proxy:
  addr: ":8080"
  target: "localhost:8081"
  db: "settler.db"

# Optional: Commands to run after LiteFS mounts the file system.
# This ensures that settlerd only starts after FUSE mount is active.
exec:
  - cmd: "bin/settlerd"