# Workflow example

Here is an example of a typical ewokstomo workflow:

![Typical workflow showing ReduceDarkFlat feeding ReconstructSlice](reconstruct_from_nx.png)

The diagram shows a minimal “slice-from-NXtomo” chain:

- External inputs (blue) are dashed into the tasks: the NXtomo file
  (`nx_path`) feeds both tasks, while `config_dict` and `slice_index` go
  directly to `ReconstructSlice`.
- `ReduceDarkFlat` reads the NXtomo file and saves reduced dark and flat
  references (`<scan>_darks.hdf5` / `<scan>_flats.hdf5`) under
  `references/`.
- `ReconstructSlice` consumes the NXtomo file plus the reduced
  darks/flats and reconstructs a single slice (configurable index) into
  `slices/<scan>_*` under the scan root (see
  [tasks](../references/tasks.md) for the exact
  naming pattern).

Outputs:

- Reduced reference files in `references/`.
- A reconstructed slice file in `slices/`, along with the Nabu
  configuration and processing options returned by the task.

Each node has a set of parameters that you can find in
[tasks](../references/tasks.md).

An ewoks workflow can be represented as a json file:

```json
{
  "directed": true,
  "multigraph": false,
  "graph": {
    "id": "reconstruct_from_nx",
    "label": "Ewoks workflow 'reconstruct_from_nx'",
    "schema_version": "1.1"
  },
  "nodes": [
    {
      "id": "reduce_task",
      "task_type": "class",
      "task_identifier": "ewokstomo.tasks.reducedarkflat.ReduceDarkFlat"
    },
    {
      "id": "slice_reconstruction_task",
      "task_type": "class",
      "task_identifier": "ewokstomo.tasks.reconstruct_slice.ReconstructSlice"
    }
  ],
  "links": [
    {
      "source": "reduce_task",
      "target": "slice_reconstruction_task",
      "data_mapping": []
    }
  ]
}
```