This app demonstrates various usages of the Monio library's monads, especially the IO and IOx (aka "reactive IO" or "observable IO") monads.

1. Clone this repo

2. run npm install

3. run npm start

By default, this will start the server locally on port 8090, and the client can thus be viewed in the browser at http://localhost:8090.

To run the server on a different port than the default 8090, set the PORT environment variable to a different number, such as PORT=3000 npm start.

By default, the client defined in the client-1 directory will be served up via the browser. To select a different client in a different directory, set the MONIO_DEMO_CLIENT_DIR to a relative (from the project root) or absolute path, such as MONIO_DEMO_CLIENT_DIR=/tmp/other-client npm start. Note that the specified directory will be treated as the web-root.

The client code uses imports with friendly specifiers (e.g., "monio/io") rather than full paths (e.g., "/js/monio/io/io.mjs") as browsers typically require. It does so by relying on Import Maps, a browser feature that allows the browser to automatically translate specifiers like "monio/io" to "/js/monio/io/io.mjs" when it finds them in import statements.

Unfortunately, browser support for Import Maps isn't so great; at time of writing, it's only Chrome/Chromium-based browsers.

To work around this limitation, the original client code (in /js/ directory) is also transpiled, with a tool called Import-Remap, so that all the import specifiers have already been translated. The outcome is that any non-Chromium browsers (Firefox, Safari, etc) will load the client files from the /js-nim/ directory rather than from the /js/ directory.

If you modify any of the client files in /js/, and want to see those changes reflected in all browsers (besides Chromium), you'll need to rebuild the /js-nim/ directory tree. In the scripts/ directory of this repository, a helper tool (scripts/build-client) is provided to perform this re-build.

To run the tool:

npm run build

Note: This tool is also automatically run whenever you start the server with npm start.

That defaults to rebuilding the client code under the /client-1/ directory. However, you can also tell the tool to run against a different client directory, like this:

npm run build -- --client=/path/to/another/client

The build tool will assume to build ESM files from the specified client directory's /js/ sub-directory to a /js-nim/ sub-directory (which must already exist).

All code and documentation are (c) 2022 Kyle Simpson and Brian Lonsdorf, and released under the MIT License. A copy of the MIT License is also included.