MapPrism

Writing a Recipe ​

This walkthrough builds a real recipe step by step: reproject a point cloud, then build a Potree tileset.

1. Decide what the pipeline should do ​

Goal: take a raw LAS file in a local coordinate system, reproject it to Web Mercator (EPSG:3857), and produce a Potree-compatible tileset for web visualization.

Steps needed:

  1. REPROJECT_LAS — transform the coordinate system
  2. BUILD_POTREE — produce the tileset

2. Check executor contracts ​

From the executor reference:

TypeAcceptsProducesParams
REPROJECT_LASinput_las: lasoutput_las: lassource_epsg, target_epsg
BUILD_POTREEinput_las: lasoutput_potree: potreenone

3. Plan artifact flow ​

  • Job input: job:input_las (the raw LAS file)
  • After reproject: step:reproject.output_las
  • After build: step:build_potree.output_potree

4. Write the step list ​

json
"recipe": [
  {
    "id": "reproject",
    "type": "REPROJECT_LAS",
    "inputs":  { "input_las": "job:input_las" },
    "outputs": { "output_las": "step:reproject.output_las" },
    "param_keys": ["source_epsg", "target_epsg"]
  },
  {
    "id": "build_potree",
    "type": "BUILD_POTREE",
    "inputs":  { "input_las": "step:reproject.output_las" },
    "outputs": { "output_potree": "step:build_potree.output_potree" }
  }
]

Key checks:

  • input_las in REPROJECT_LAS.inputs matches the executor's accepts slot name
  • output_las in REPROJECT_LAS.outputs matches the executor's produces slot name
  • build_potree reads from step:reproject.output_las — the value reproject wrote

5. Add an on_exit hook (optional but recommended) ​

Add a CALL_WEBHOOK to notify when the job finishes. It needs to wait for something — use the last artifact produced:

json
"on_exit": {
  "id": "call_webhook",
  "type": "CALL_WEBHOOK",
  "inputs": { "waits_for": "step:build_potree.output_potree" },
  "param_keys": ["webhook_url"]
}

6. Assemble the full recipe ​

json
{
  "name": "reproject-and-build-potree",
  "version": "1.0.0",
  "definition": {
    "recipe": [
      {
        "id": "reproject",
        "type": "REPROJECT_LAS",
        "inputs":  { "input_las": "job:input_las" },
        "outputs": { "output_las": "step:reproject.output_las" },
        "param_keys": ["source_epsg", "target_epsg"]
      },
      {
        "id": "build_potree",
        "type": "BUILD_POTREE",
        "inputs":  { "input_las": "step:reproject.output_las" },
        "outputs": { "output_potree": "step:build_potree.output_potree" }
      }
    ],
    "on_exit": {
      "id": "call_webhook",
      "type": "CALL_WEBHOOK",
      "inputs": { "waits_for": "step:build_potree.output_potree" },
      "param_keys": ["webhook_url"]
    }
  }
}

7. Submit a job using this recipe ​

bash
curl -X POST https://dev.mapprism.com/ordo/jobs \
  -H "Authorization: Bearer <API_TOKEN>" \
  -H "Content-Type: application/json" \
  -d '{
    "recipe": {
      "name": "reproject-and-build-potree",
      "version": "1.0.0",
      "definition": { ... }
    },
    "inputs": {
      "job:input_las": {
        "type": "las",
        "uri": "development/survey/dataset.las",
        "hash": "abc123"
      }
    },
    "params": {
      "reproject": {
        "source_epsg": "EPSG:2271",
        "target_epsg": "EPSG:3857"
      },
      "call_webhook": {
        "webhook_url": "https://myapp.example.com/hooks/processing-done"
      }
    },
    "outputs": {
      "step:build_potree.output_potree": {
        "path": "development/results/survey/potree"
      }
    }
  }'

Response:

json
{ "id": 7 }

Poll with GET /ordo/jobs/7 until job.status is success or failed.