> ## Documentation Index
> Fetch the complete documentation index at: https://docs.screenjson.com/llms.txt
> Use this file to discover all available pages before exploring further.

# Pipelines

> Compose tasks into ordered pipelines submitted via POST /push.

A **pipeline** is an ordered list of task names submitted to the queue as a single job. Tasks run sequentially against the output of the previous step.

## Submission shape

```json theme={null}
{
  "input_key":   "screenplays/input/script.fdx",
  "output_key":  "screenplays/output/script-v1",
  "document_id": "12345",
  "tasks":       ["convert-fdx-to-screenjson", "validate-screenjson"],
  "vars":        { "encrypt_key": "secret" },
  "webhook":     "https://example.com/callback",
  "tenant_id":   "acme"
}
```

Submitted to [`POST /push`](/api-reference/greenlight/endpoint/push-job).

## Fields

| Field         | Type      | Required | Purpose                                                                 |
| ------------- | --------- | -------- | ----------------------------------------------------------------------- |
| `input_key`   | string    | ✓        | Object key of the source file in `S3_INPUT_BUCKET`.                     |
| `output_key`  | string    | ✓        | Base prefix for all pipeline outputs in `S3_OUTPUT_BUCKET`.             |
| `document_id` | string    | ✓        | Your own identifier. Included in events and webhook payloads.           |
| `tasks`       | string\[] | ✓        | One or more task names from [the catalogue](/tools/greenlight/tasks).   |
| `vars`        | object    | —        | Task variables — e.g. `encrypt_key`. Merged with task-defined `params`. |
| `webhook`     | string    | —        | Per-job webhook URL. Combined with `DEFAULT_WEBHOOK_URLS`.              |
| `tenant_id`   | string    | —        | Arbitrary tenant tag; surfaces in metrics and webhook payloads.         |

## Example pipelines

### FDX → validated ScreenJSON

```json theme={null}
{
  "input_key":   "screenplays/input/script.fdx",
  "output_key":  "screenplays/output/script",
  "document_id": "S1E04",
  "tasks": ["convert-fdx-to-screenjson", "validate-screenjson"]
}
```

### ScreenJSON → multi-format ZIP

```json theme={null}
{
  "input_key":   "screenplays/input/script.json",
  "output_key":  "screenplays/output/bundle",
  "document_id": "S1E04",
  "tasks": [
    "export-to-fdx",
    "export-to-fountain",
    "export-to-pdf",
    "zip-output"
  ]
}
```

### Convert from Fountain, encrypt for distribution

```json theme={null}
{
  "input_key":   "screenplays/input/script.fountain",
  "output_key":  "screenplays/output/encrypted",
  "document_id": "S1E04",
  "tasks": ["convert-fountain-to-screenjson", "encrypt-screenjson"],
  "vars":  { "encrypt_key": "mysecretkey123" }
}
```

## How it runs

1. A worker claims the job from Redis (`REDIS_INPUT_QUEUE`).
2. It downloads `input_key` from object storage.
3. For each task in order, it invokes `greenlight.<handler>` against the current working file. Outputs land in `{output_key}/{task.output_dir}/{stem}.{ext}`.
4. Results are written to `REDIS_RESULTS_QUEUE` with TTL `REDIS_RESULTS_TTL` hours.
5. Webhooks fire (per-job and defaults).
6. Notifications fan out to any configured drivers.

Failed tasks abort the pipeline; outputs already written stay in place.

## Status and results

Track progress with:

* [`GET /results`](/api-reference/greenlight/endpoint/list-results) — paginated list of recent jobs.
* [`GET /results/{id}`](/api-reference/greenlight/endpoint/get-result) — one specific job, including per-task timings and output keys.
* [`GET /workers`](/api-reference/greenlight/endpoint/get-workers) — live worker status.