Feature: copy and override metadata.Fields

Author: pylover

setup.py

@@ -18,7 +18,7 @@
 
 
 dependencies = [
-    'yhttp >= 5.2, < 6',
+    'yhttp >= 5.3, < 6',
     'yhttp-dbmanager >= 4, < 5',
     'sqlalchemy >= 2.0.32',
 ]

tests/test_metadata.py

@@ -50,8 +50,13 @@ def post(req):
         assert response.json == dict(id=2, title='foo', alias='OOF')
 
 
-def test_metadata_args():
-    col = m.String('foo', length=(0, 20)).column()
+def test_metadata_example():
+    field = m.String('foo', length=(0, 20), example='123')
+    assert field.example == '123'
+
+
+def test_metadata_column():
+    col = m.String('foo', length=(0, 20), example='123').column()
     assert isinstance(col, MappedColumn)
     assert isinstance(col.column.type, sa.String)
     assert col.column.type.length == 20
@@ -64,3 +69,21 @@ def test_metadata_args():
     col = m.Integer('foo').column()
     assert isinstance(col, MappedColumn)
     assert isinstance(col.column.type, sa.Integer)
+
+
+def test_metadata_override():
+    foo = m.String('foo', length=(0, 20), example='123')
+    bar = foo(name='bar')
+    assert bar.name == 'bar'
+    assert bar.length == (0, 20)
+    assert bar.example == '123'
+
+    bar = foo(name='bar', length=(1, 10))
+    assert bar.name == 'bar'
+    assert bar.length == (1, 10)
+    assert bar.example == '123'
+
+    bar = bar(example='321')
+    assert bar.name == 'bar'
+    assert bar.length == (1, 10)
+    assert bar.example == '321'

yhttp/ext/sqlalchemy/metadata.py

@@ -7,9 +7,18 @@
 
 
 class FieldMixin(metaclass=abc.ABCMeta):
-    def __init__(self, *args, **kwargs):
+    def __init__(self, *args, example=None, **kwargs):
+        self.example = example
         super().__init__(*args, **kwargs)
 
+    def __call__(self, *, example=None, **kwargs):
+        kwargs['example'] = self.example if example is None else example
+
+        if 'name' not in kwargs:
+            kwargs['name'] = self.name
+
+        return super(FieldMixin, self).__call__(**kwargs)
+
     @property
     @abc.abstractmethod
     def _satype(self):