manifest.json

The manifest.json file is critical - it declares all external resources your app needs. Domo uses this to:

1. Know which datasets, collections, workflows, and code engine functions to connect
2. Map aliases (used in your code) to actual Domo resource IDs (configured at publish time)

For package create/update lifecycle details that feed packagesMapping, use:

• ~/.agents/skills/code-engine-create/SKILL.md
• ~/.agents/skills/code-engine-update/SKILL.md

Basic structure

{
  "name": "My App Name",
  "version": "1.0.0",
  "id": "xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx",
  "fullpage": true,
  "size": {
    "width": 4,
    "height": 3
  },
  "datasetsMapping": [],
  "collections": [],
  "workflowMapping": [],
  "packagesMapping": []
}

Key properties

• name / version - App metadata
• id - Generated on first publish (see deployment section)
• fullpage - Set true for full-page apps
• size - Card dimensions (width/height in grid units)
• datasetsMapping - Datasets the app can query
• collections - AppDB collections for storage
• workflowMapping - Workflows the app can trigger
• packagesMapping - Code Engine function mappings and contracts

Required files

• manifest.json - App configuration (required)
• thumbnail.png - App thumbnail image (required, must be 300x300 pixels, must be alongside manifest.json)

Dataset Mapping Structure

{
  "datasetsMapping": [
    {
      "alias": "transactions",           // Used in code: new Query().fetch('transactions')
      "dataSetId": "abc-123-def-456",   // ⚠️ Use 'dataSetId' NOT 'id'
      "fields": []                       // ⚠️ REQUIRED - must be present even if empty
    }
  ]
}

Critical points:

• Use dataSetId (not id) for the dataset identifier
• fields array is required - must be present even if empty []
• Omitting fields causes: Cannot read properties of undefined (reading 'map')
• Alias names must be identifier-safe: letters/numbers only (recommended ^[A-Za-z][A-Za-z0-9]*$)
• Do not use spaces, hyphens, dots, or other special characters in aliases

Alias naming constraints (all mappings)

Applies to dataset aliases, Code Engine aliases, workflow aliases, and any alias your app code references.

✅ Good: storeSales, Sales2026, RevenuePulse
❌ Bad: store-sales, store sales, store.sales, store@sales

If an alias includes special characters, runtime calls can fail or mappings can be hard to resolve consistently.

Code Engine packagesMapping structure

{
  "packagesMapping": [
    {
      "name": "myPackage",
      "alias": "myFunction",
      "packageId": "00000000-0000-0000-0000-000000000000",
      "version": "1.0.0",
      "functionName": "myFunction",
      "parameters": [
        {
          "name": "param1",
          "displayName": "param1",
          "type": "decimal",
          "value": null,
          "nullable": false,
          "isList": false,
          "children": [],
          "entitySubType": null,
          "alias": "param1"
        }
      ],
      "output": {
        "name": "result",
        "displayName": "result",
        "type": "number",
        "value": null,
        "nullable": false,
        "isList": false,
        "children": [],
        "entitySubType": null,
        "alias": "result"
      }
    }
  ]
}

Code Engine manifest gotchas:

• Use packagesMapping (with s), not packageMapping.
• Include full contract fields on each parameter and output.
• Ensure parameter names/types/nullability match what app code actually sends.
• Set explicit packagesMapping[].version (for example "1.0.0") when you want deterministic behavior.
• version: null is treated as unpinned/latest behavior and will usually remain/display as null after publish.

Collection Mapping Structure (collectionsMapping)

When wiring an app to an existing AppDB collection in published manifests, use collectionsMapping entries with id + name.

{
  "collectionsMapping": [
    {
      "id": "47bd2c9e-b22d-4436-8265-4798be8b218e",
      "name": "RandomFunIdeas",
      "syncEnabled": false
    }
  ]
}

Collection mapping gotchas:

• Do not use ad-hoc keys like alias + collectionId in collectionsMapping; this can fail manifest parsing.
• name is required for mapped collection objects.
• For existing collection wiring, default syncEnabled to false unless app requirements explicitly call for synchronized dataset behavior.

FileSets — no manifest entry needed

FileSets are the exception to the "declare everything in manifest" pattern. There is no filesetsMapping or equivalent key. Reference the fileset ID directly as a constant in your service code:

// src/services/filesetApi.js
const FILESET_ID = 'b6ebf7e9-64ae-4e6d-b8ca-b356fe62923f';

The fileset ID is a UUID you get from the Domo UI or via community-domo-cli filesets search. See the fileset-api skill for the full API pattern.