Leaf Agent

A Go daemon that sits next to a Fossil repo and keeps it synced over NATS.

Data Flow

    right
    R: cylinder "repo.fossil" color white fill 0x3a3a3a width 1.2 height 0.5 rad 3px
    move 0.2
    arrow color white thick <->
    move 0.1
    A: box "Leaf Agent" color white fill 0x2a6b3a width 1.5 height 0.5 rad 5px
    move 0.2
    arrow color white thick "sync request" above
    move 0.1
    N: cylinder "NATS" color white fill 0x2a4a6b width 1.0 height 0.5 rad 5px
    move 0.2
    arrow color white thick
    move 0.1
    B: box "Bridge" color white fill 0x6b5a2a width 1.2 height 0.5 rad 5px
    move 0.2
    arrow color white thick "HTTP" above
    move 0.1
    F: box "Fossil" color white fill 0x6b2a2a width 1.2 height 0.5 rad 5px

How It Works

1. Opens a .fossil repo — reads project/server codes from SQLite
2. Connects to NATS
3. Polls every 5s (configurable):
   • Checks unsent/unclustered tables
   • If new artifacts found, calls sync.Sync() via NATS transport
4. SIGUSR1 triggers immediate sync
5. SIGINT/SIGTERM graceful shutdown

Usage

leaf-agent --repo /path/to/repo.fossil \
           --nats nats://localhost:4222 \
           --poll 5s \
           --push --pull

Concurrency

The poll goroutine is the sole executor of sync. SyncNow() sends on a buffered channel — it never calls sync directly. This avoids concurrent SQLite access.

See Also

• Bridge — the other half
• Home — architecture overview