Data Spec

JSON message format between Web and Native

This document describes the data format exchanged over the uniBridgeCall bridge.

The goal is simple: make it clear what JS sends to native, and how native replies with data.

Message from JS to Native

Every call from JavaScript sends a JSON object with this shape:

{
  "type": "string",
  "data": {}
}

Fields

Field	Description
`type`	Protocol name, e.g. `close-page`, `get-user-info`, `log-event`
`data`	Payload. Always an object (use `{}` when no data is needed)

For calls that need a response (library request()), iOS also includes a callbackName. Android does not use this field — the response is delivered through the callHandler callback instead.

Examples

Simple send (no response expected)

{ "type": "close-page", "data": {} }

Send with payload

{
  "type": "log-event",
  "data": { "name": "page_view", "page": "/home" }
}

Call that expects a response

{
  "type": "get-user-info",
  "data": { "userId": 42 }
}

(On iOS a callbackName field will also be present for response delivery.)

Reply from Native to JS

When JS uses request() (i.e. expects a reply), native must return a JSON string.

Recommended response format

{
  "errcode": 0,
  "errmsg": "ok",
  "data": {}
}

Examples

Success

{
  "errcode": 0,
  "errmsg": "ok",
  "data": { "name": "Alice", "id": 42 }
}

Business error (still a successful bridge call)

{
  "errcode": 1001,
  "errmsg": "insufficient balance",
  "data": null
}

How native delivers the reply

Android: Call the response callback that was passed when you registered the uniBridgeCall handler: callback.onCallBack(jsonString)
iOS: Call the global function whose name was provided in callbackName: window[callbackName](jsonString)

The JS side parses the string as JSON. If parsing fails, the promise rejects with a protocol error. Business errors (errcode != 0) are returned as resolved values — the bridge call itself succeeds.