Merge pull request #194 from pyscript/experimental_remote_packages

Experimental remote packages

Author: ntoll

docs/user-guide/configuration.md

@@ -85,11 +85,12 @@ _single_ `<py-config>` or `<mpy-config>` tag in your HTML document:
 
 There are five core options ([`interpreter`](#interpreter), [`files`](#files),
 [`packages`](#packages), [`js_modules`](#javascript-modules) and
-[`sync_main_only`](#sync_main_only)) and an experimental flag
+[`sync_main_only`](#sync_main_only)) and two experimental flags:
 ([`experimental_create_proxy`](#experimental_create_proxy)) that can be used in
-the configuration of PyScript. The user is also free to define
-arbitrary additional configuration options that plugins or an app may require
-for their own reasons.
+the configuration of PyScript and
+([`experimental_remote_packages`](#experimental_remote_packages)) which allows
+remotely hosted packages. The user is also free to define arbitrary additional
+configuration options that plugins or an app may require for their own reasons.
 
 ### Interpreter
 
@@ -554,6 +555,37 @@ In this experimental phase, we suggest trying `0`, `30` or a value that won't
 likely bypass the browser rendering of 60fps. Of course, `1000` (i.e. a second)
 would be a fun, if greedy, experiment.
 
+### experimental_remote_packages
+
+Specially designed to allow custom pure Python packages, it is possible to
+specify a remote `.toml` or `.json` configuration file within the list of
+packages:
+
+```TOML title="Using the experimental_remote_packages flag in TOML."
+experimental_remote_packages = true
+packages = ['numpy', 'https://remote.host.com/my_package/v1/config.toml']
+```
+
+The remote config is basically a subset of any other PyScript config with the
+only exception that its `name` field must specify the package name, which will
+then be used to import such package via regular imports:
+
+```TOML title="A remote config example"
+name = "my_package"
+
+# a remote config can include packages, even remote ones
+packages = ['matplotlib']
+
+# files are resolved relatively to this config URL
+[files]
+"./__init__.py" = ""
+"./sub/module.py" = ""
+"./main.py" = ""
+```
+
+The bootstrap will take care of fetching and preparing the remote package so
+that all the code will need to do is: `from my_package import util`.
+
 ### debug
 
 When using Pyodide, if the `debug` setting is set to `true`, then Pyodide will