Fix #24 -- Move config to pyproject.yaml

The python community has widely adopeted PIP 621. Therefore,
it seems the best place to implement it in this package too.

There are two key changes:

1. The config moves to `tool.importmap`.
2. The importmap config allows adding multiple entries.

Additionally, this commits removes two dependencies:
* marshmellow
* tomli (python_version>=12.0)

README.md

@@ -31,21 +31,23 @@ INSTALLED_APPS = [
 ]
 ```
 
-### 2. Create an `importmap.toml` file
+### 2. Configuring an import map
 
-This should live next to your `manage.py` file.
-Here you'll add a list of "packages" you want to use.
+You JavaScript dependencies are conveniently located in your`pyproject.toml` file.
 
-The "name" can be anything, but should probably be the same as what it you would import from in typical bundling setups (i.e. `import React from "react"`).
-
-The "source" will get passed on to the [jspm.org generator](https://jspm.org/docs/api#install), but is basically the `<npm package>@<version>` you want to use.
+They are listed under `[tool.importmap.dependencies]` and you can add them there. The format is `name = "version"`,
+similar to how you would add a dependency to your `package.json` file.
 
 ```toml
-[[packages]]
-name = "react"
-source = "[email protected]"
+# pyproject.toml
+[tool.importmap.dependencies]
+react = "17.0.2"
+react-dom = "17.0.2"
 ```
 
+[jspm.org generator](https://jspm.org/docs/api#install) is used lock and serve the dependencies,
+but is basically just like installing them via `npm i <npm package>@<version>`.
+
 ### 3. Run `importmap_generate`
 
 To resolve the import map, you'll need to run `python manage.py importmap_generate`.

importmap/core.py

@@ -2,36 +2,22 @@
 import json
 import logging
 import os
+from pathlib import Path
 
-import tomli
-from marshmallow import Schema, fields
+try:
+    import tomllib
+except ImportError:
+    import tomli as tomllib
 
 from .generator import ImportmapGenerator
 
 logger = logging.getLogger(__name__)
 
 
-DEFAULT_CONFIG_FILENAME = "importmap.toml"
+DEFAULT_CONFIG_FILENAME = "pyproject.toml"
 DEFAULT_LOCK_FILENAME = "importmap.lock"
 
 
-class PackageSchema(Schema):
-    name = fields.String(required=True)
-    source = fields.String(required=True)
-    # preload
-    # vendor, or vendor all is one option?
-
-
-class ConfigSchema(Schema):
-    packages = fields.List(fields.Nested(PackageSchema), required=True)
-
-
-class LockfileSchema(Schema):
-    config_hash = fields.String(required=True)
-    importmap = fields.Dict(required=True)
-    importmap_dev = fields.Dict(required=True)
-
-
 def hash_for_data(data):
     return hashlib.md5(json.dumps(data, sort_keys=True).encode("utf-8")).hexdigest()
 
@@ -42,8 +28,8 @@ def __init__(
         config_filename=DEFAULT_CONFIG_FILENAME,
         lock_filename=DEFAULT_LOCK_FILENAME,
     ):
-        self.config_filename = config_filename
-        self.lock_filename = lock_filename
+        self.config_file = Path(config_filename)
+        self.lock_file = Path(lock_filename)
         self.load()
 
     @classmethod
@@ -70,7 +56,7 @@ def load(self):
             # No config = no map and no lockfile
             self.map = {}
             self.map_dev = {}
-            self.delete_lockfile()
+            self.lock_file.unlink(missing_ok=True)
             return
 
         lockfile = self.load_lockfile()
@@ -95,34 +81,23 @@ def generate(self, force=False):
             self.save_lockfile(lockfile)
 
     def load_config(self):
-        # TODO raise custom exceptions
-
-        if not os.path.exists(self.config_filename):
-            logger.warning(f"{self.config_filename} not found")
+        if not self.config_file.exists():
             return {}
+        with self.config_file.open("rb") as f:
+            pyproject = tomllib.load(f)
 
-        with open(self.config_filename, "r") as f:
-            # why doesn't tomli.load(f) work?
-            toml_data = tomli.loads(f.read())
-
-        return ConfigSchema().load(toml_data)
+        return pyproject["tool"]["importmap"]
 
     def load_lockfile(self):
-        if not os.path.exists(self.lock_filename):
+        if not self.lock_file.exists():
             return {}
 
-        with open(self.lock_filename, "r") as f:
-            json_data = json.load(f)
-
-        return LockfileSchema().load(json_data)
+        with self.lock_file.open("r") as f:
+            return json.load(f)
 
     def save_lockfile(self, lockfile):
-        with open(self.lock_filename, "w+") as f:
+        with self.lock_file.open("w+") as f:
             json.dump(lockfile, f, indent=2, sort_keys=True)
 
-    def delete_lockfile(self):
-        if os.path.exists(self.lock_filename):
-            os.remove(self.lock_filename)
-
     def generate_map(self, *args, **kwargs):
         return ImportmapGenerator.from_config(self.config, *args, **kwargs).generate()

importmap/generator.py

@@ -17,12 +17,11 @@ def __init__(self, targets, development=False, provider="jspm"):
 
     @classmethod
     def from_config(cls, config, *args, **kwargs):
-        targets = []
-
-        for map in config["packages"]:
-            targets.append(map["source"])
-
-        return cls(targets, *args, **kwargs)
+        return cls(
+            [f"{package}@{version}" for package, version in config["dependencies"].items()],
+            *args,
+            **kwargs,
+        )
 
     def get_env(self):
         if self.development: