Merge pull request #18 from dpwrussell/include_overidden_by_fk_field_…

…that_should_be_serialized

Include overidden by fk field that should be serialized

marshmallow_sqlalchemy/convert.py

@@ -57,8 +57,14 @@ def fields_for_model(self, model, include_fk=False, fields=None):
             if fields and prop.key not in fields:
                 continue
             if hasattr(prop, 'columns'):
-                if not include_fk and prop.columns[0].foreign_keys:
-                    continue
+                if not include_fk:
+                    # Only skip a column if there is no overriden column
+                    # which does not have a Foreign Key.
+                    for column in prop.columns:
+                        if not column.foreign_keys:
+                            break
+                    else:
+                        continue
             field = self.property2field(prop)
             if field:
                 result[prop.key] = field

tests/test_marshmallow_sqlalchemy.py

@@ -118,6 +118,30 @@ class SubstituteTeacher(Base):
         id = sa.Column(sa.Integer, sa.ForeignKey('teacher.id'),
                        primary_key=True)
 
+    class Paper(Base):
+        __tablename__ = 'paper'
+
+        satype = sa.Column(sa.String(50))
+        __mapper_args__ = {
+            'polymorphic_identity': 'paper',
+            'polymorphic_on': satype
+        }
+
+        id = sa.Column(sa.Integer, primary_key=True)
+        name = sa.Column(sa.String, nullable=False, unique=True)
+
+    class GradedPaper(Paper):
+        __tablename__ = 'gradedpaper'
+
+        __mapper_args__ = {
+            'polymorphic_identity': 'gradedpaper'
+        }
+
+        id = sa.Column(sa.Integer, sa.ForeignKey('paper.id'),
+                       primary_key=True)
+
+        marks_available = sa.Column(sa.Integer)
+
     # So that we can access models with dot-notation, e.g. models.Course
     class _models(object):
         def __init__(self):
@@ -126,6 +150,8 @@ def __init__(self):
             self.Student = Student
             self.Teacher = Teacher
             self.SubstituteTeacher = SubstituteTeacher
+            self.Paper = Paper
+            self.GradedPaper = GradedPaper
     return _models()
 
 @pytest.fixture()
@@ -153,6 +179,15 @@ class Meta:
     class SubstituteTeacherSchema(ModelSchema):
         class Meta:
             model = models.SubstituteTeacher
+
+    class PaperSchema(ModelSchema):
+        class Meta:
+            model = models.Paper
+            sqla_session = session
+
+    class GradedPaperSchema(ModelSchema):
+        class Meta:
+            model = models.GradedPaper
             sqla_session = session
 
     class HyperlinkStudentSchema(ModelSchema):
@@ -168,6 +203,8 @@ def __init__(self):
             self.StudentSchema = StudentSchema
             self.TeacherSchema = TeacherSchema
             self.SubstituteTeacherSchema = SubstituteTeacherSchema
+            self.PaperSchema = PaperSchema
+            self.GradedPaperSchema = GradedPaperSchema
             self.HyperlinkStudentSchema = HyperlinkStudentSchema
     return _schemas()
 
@@ -227,6 +264,11 @@ def test_include_fk(self, models):
         student_fields2 = fields_for_model(models.Student, include_fk=True)
         assert 'current_school_id' in student_fields2
 
+    def test_overridden_with_fk(self, models):
+        graded_paper_fields = fields_for_model(models.GradedPaper,
+                                               include_fk=False)
+        assert 'id' in graded_paper_fields
+
 def make_property(*column_args, **column_kwargs):
     return column_property(sa.Column(*column_args, **column_kwargs))