WIP: Add wtforms

setup.cfg

@@ -47,6 +47,9 @@ zip_safe = true
 
 [options.extras_require]
 contrib_click = click
+contrib_wtforms =
+    wtforms
+    flask-wtf
 
 [options.packages.find]
 where = src

src/easy_config/contrib/wtforms.py

@@ -0,0 +1,29 @@
+"""Test the Flask-WTF wrapper."""
+
+import dataclasses
+from typing import Type
+
+from easy_config import EasyConfig
+from flask_wtf import FlaskForm
+from wtforms import BooleanField, IntegerField, StringField
+from wtforms.validators import DataRequired
+
+type_to_field = {
+    str: StringField,
+    int: IntegerField,
+    bool: BooleanField,
+}
+
+
+def form_from_config(cls: Type[EasyConfig]):
+    """Build a Flask-WTF form based on the given EasyConfig class."""
+    attrs = {}
+
+    for field in dataclasses.fields(cls):
+        field_cls = type_to_field[field.type]
+        attribute = field_cls(field.name, validators=[DataRequired()])
+        if field.default is not dataclasses.MISSING:
+            attribute.default = field.default
+        attrs[field.name] = attribute
+
+    return type(f'{cls.NAME}Form', (FlaskForm,), attrs)

tests/test_contrib_wtforms.py

@@ -0,0 +1,35 @@
+# -*- coding: utf-8 -*-
+
+"""Test the Flask-WTF wrapper."""
+
+import flask
+
+from easy_config import EasyConfig
+from easy_config.contrib.wtforms import form_from_config
+
+
+def test_with_default():
+    """Test building a form."""
+
+    class ExampleConfig(EasyConfig):
+        """Example EasyConfig subclass to test with."""
+
+        FILES = None
+        NAME = 'MyProgram'
+
+        bool_1: bool
+        bool_2: bool = True
+        bool_3: bool = True
+
+    form_cls = form_from_config(ExampleConfig)
+    app = flask.Flask('test_app')
+
+    with app.app_context():
+        form = form_cls(csrf_enabled=False)
+        for field in form:
+            print(field)
+
+        fields = list(form)
+        assert 1 == len(fields)
+        field = fields[0]
+        assert str(field) == '<input id="number" name="number" required type="checkbox" value="y">'

tox.ini

@@ -31,6 +31,7 @@ deps =
     pytest
 extras =
     contrib_click
+    contrib_wtforms
 commands = coverage run --parallel -m pytest tests {posargs}
 description = Run pytest tests with coverage.