The watch command (truss chains watch) combines
the best of local development and full deployment. watch lets you run on an
exact copy of the production hardware and interface but gives you live code
patching that lets you test changes in seconds without creating a new
deployment.
To use truss chains watch:
- Push a chain in development mode (i.e.
publish and promote flags are
false).
- Run the watch command
truss chains watch SOURCE. You can also add the
watch option to the push command and combine both to a single step.
- Each time you edit a file and save the changes, the watcher patches the
remote deployments. Updating the deployments might take a moment, but is
generally much faster than creating a new deployment.
- You can call the chain with test data via
cURL or the playground dialogue
in the UI and observe the result and logs.
- Iterate steps 3. and 4. until your chain behaves in the desired way.
Selective Watch
Some large ML models might have a slow cycle time to reload (e.g. if the
weights are huge). For this case, we provide a “selective” watch option. For
example if your chain has such a heavy model Chainlet and other Chainlets
that contain only business logic, you can iterate on those, while not patching
and reloading the heavy model Chainlet.
This feature is really useful for advanced use case, but must be used with
caution.
If you change the code of a Chainlet not watched, in particular I/O types,
you get an inconsistent deployment.
truss chains watch ... --experimental-chainlet-names=ChainletA,ChainletB
