Design async data injection mechanism

[justsml]

Sometimes business rules need access to external data (from a Database, HTTP API, AI/ML Service, etc.)

Goals

• [ ] Support JSON config-style declaration.
• [ ] Securely reference API keys.
• [ ] Pluggable / layered design. (Similar to inputMap & outputMap designs.)
• [ ] Rely on existing 'client' APIs. (fetch, pg, etc)

[chhatch]

Are you thinking something like this?

{
  map: '$IO::fetchItems()',
  run: { return: '$item.id' },
}

// fetchItems.config.json
{
  "url": "items.com/api?key=$ApiKey",
  "ApiKey": "SECURE_ENV_VAR",
  "method": "GET",
  "headers": [...],
  "dataPath": "body.data.items",
  "validator": "./validator.js"
}