Updated Readme

README.md

@@ -24,12 +24,20 @@ This is a minimal proof-of-concept for FDC3 For the Web.
 
  - In `\lib`:  A minimal implementation of web api retrieval.  This relies on the `post-message` strategy for communicating between apps and the desktop agent.  This supports two functions:
 
-   - `supply` (in `supply.ts`):  Called by the desktop agent on startup, allows it to supply FDC3 APIs to apps when they ask for one.  This takes the following parameters:
-     - A `url` of a piece of javascript that the App will load in order to initialise it's API.
-     - A `checker`, which checks the origin window for the API request.  It should be a window that the Desktop Agent is aware of.
-     - A `detailsResolver`, which returns a map of properties to send to the API requestor that should be used to instantiate the API.
+   - **For the App**: `load` (in `load.ts`): Called (with options) by an FDC3 Aoo to retrieve the API.  This retrieves `details` from the desktop agent and initialises a `DesktopAgent` API implementation, returning it in a promise.  There are various options available:
+
+    - _strategies_: This allows plugable strategies for getting the DA.  Two exist:
+      -  `electron-event` which waits for `window.fdc3` to be set and 
+      - `post-message` which fires a post message up to the opening window/iframe (or whatever is set in the `frame` option) asking for details of how to construct a `DesktopAgent` API implementation.
+
+    - _methods_:  The app can also suggest methods ways in which it might want to construct the `DesktopAgent` API.  The desktop agent is obliged to try and return a response back to the app detailing one of the approaches that the app asks for.  Two exist so far:
+      - `js-inject` : The desktop agent responds with a URL of some javascript, loaded by the app to create a `DesktopAgent` API.  (See App2 which does this)
+      - `post-message-protocol` : The app expects to communicate with the desktop agent via standard [Desktop-Agent-Bridging](https://fdc3.finos.org/docs/next/agent-bridging/spec) messages, sent and received via post-message. 
 
-   - `load` (in `load.ts`): Called (with options) by an FDC3 Aoo to retrieve the API.  This retrieves the `url` and `details` from the desktop agent and initialises a `DesktopAgent` implementation, returning it in a promise.
+
+   - **For the desktop agent**: `supply` (in `agent/supply.ts`):  Called by the desktop agent on startup, allows it to supply FDC3 APIs to apps when they ask for one via the `post-message` strategy.  This takes the following parameters:
+     - A `checker`, which checks the origin window for the API request.  It should be a window that the Desktop Agent is aware of.
+     - A map of `detailsResolver`s, which returns a map of properties to send to the API requestor (the app) that should be used to instantiate the API.  This map is keyed by the names of the _methods_ above.
 
  - In `\demo`:  A fixture for demonstrating the above, containing two apps, `app1` and `app2` and a rudimentary `dummy-desktop-agent` all of which use the `webc3.ts` library.
 
@@ -39,14 +47,13 @@ This is a minimal proof-of-concept for FDC3 For the Web.
 
 - Since this uses Vite, you can modify the code and see it running the browser immediately.
 - This currently only supports FDC3 2.0
-
+- This supports cross-origin, (at least on my machine!) you can configure hostnames in `dummy-desktop-agent.ts` to try this out.
+- Also supports the difference between frames and tabs.
 
 ## TO DO
 
- - Figure out options, setting global
  - Fallback strategy in case FDC3 API isn't available (currently promise never resolves)
  - Sanitisation of response from the Desktop Agent
  - Handing of fdc3Ready
- - Handling of Electron container injection approach