Fusee DocsRunning it
The same workflow code runs in five arrangements. Start with the first and move when you need what the next one gives.
| Where the journal lives | Code runs in | When | |
|---|---|---|---|
| Embedded | a directory on the app's disk | the app | one process, or one per directory |
| Server | fusee server's disk | the app (workers) | several processes, one store |
| Replicated | three or five servers | the app (workers) | surviving a lost machine |
| Invoked | a server | functions it calls (Lambda, Cloud Run, Vercel) | nothing running while runs sleep |
| Kubernetes | a StatefulSet of servers | the app's pods | the above, managed |
Embedded
const engine = await Engine.open({ dir: "./data", workflows: [checkout] });The engine is a library: no server, no network. A run's records go to the
directory's log with one flush per batch; a crash loses nothing that was
acknowledged. One process opens a directory at a time (a second one is
told which process holds it). Use durability modes to
choose the flush (fsync, fullfsync on macOS) and memory for tests.
Server
fusee server --dir /var/lib/fusee --listen 0.0.0.0:7600 --token-file /etc/fusee/token --http 0.0.0.0:7601const engine = await Engine.open({ durability: "server", address: "fusee.internal:7600?token-file=/etc/fusee/token", workflows: [checkout] });Workers lease shards from the server and run their runs; when a worker
dies its shards go to another. Clients (Client.connect, the CLI, the HTTP
API) reach any run through the server. Tokens and scopes: deploying.
Details: server mode.
Replicated
Three or five servers, each with its own disk, agree on every record before it is acknowledged; a majority must be up. Workers connect to the group as to one server and follow its primary. Replication covers setup, membership changes and what is measured.
Invoked
The server calls an HTTP endpoint when a shard has work and no worker: the function opens an engine for that shard, runs it until idle, and returns. Nothing runs while workflows sleep for a week.
fusee server --dir /var/lib/fusee --listen 0.0.0.0:7600 --token-file /etc/fusee/token \
--invoke https://worker.example.com/invoke --invoke-secret-file /etc/fusee/invoke-secretEach SDK has a handler that verifies the request and runs the shard (server mode, invoked workers).
Kubernetes
helm install fusee deploy/helm/fusee --set members=3 runs a replicated
group as a StatefulSet with its token in a Secret; deploy/terraform does
the same through Terraform, deploy/systemd runs one server on a host,
and deploy/monitoring has alert rules and a dashboard over /metrics.
See deploying.
Watching it
/metrics (Prometheus), the UI on the --http address, fusee runs ls --status stuck, and the operations page: disk checks,
backups, upgrades, traces.