backend: add some sample tests

Not comprehensive but enough of a starting point for further modifications.

Author: kahkeng

README.md

@@ -15,7 +15,23 @@ cd backend
 python3 -m venv venv
 source venv/bin/activate
 pip install -r requirements.txt
+```
+
+Seed the database
+
+```
 python seed.py
+```
+
+Run tests (optional)
+
+```
+pytest
+```
+
+Start backend server
+
+```
 flask run
 ```
 

backend/models.py

@@ -3,7 +3,7 @@
                             backref)
 from sqlalchemy.ext.declarative import declarative_base
 
-engine = create_engine('sqlite:///database.sqlite3', convert_unicode=True)
+engine = create_engine('sqlite:///database.sqlite3')
 db_session = scoped_session(sessionmaker(autocommit=False,
                                          autoflush=False,
                                          bind=engine))

backend/requirements.txt

@@ -1,4 +1,5 @@
 aniso8601==7.0.0
+attrs==19.3.0
 click==7.1.2
 Flask==1.1.2
 Flask-GraphQL==2.0.1
@@ -7,14 +8,23 @@ graphene-sqlalchemy==2.3.0
 graphql-core==2.3.2
 graphql-relay==2.0.1
 graphql-server-core==1.2.0
+importlib-metadata==1.7.0
 install==1.3.3
 itsdangerous==1.1.0
 Jinja2==2.11.2
 MarkupSafe==1.1.1
+more-itertools==8.4.0
+packaging==20.4
+pluggy==0.13.1
 promise==2.3
+py==1.9.0
+pyparsing==2.4.7
+pytest==5.4.3
 python-dotenv==0.14.0
 Rx==1.6.1
 singledispatch==3.4.0.3
 six==1.15.0
 SQLAlchemy==1.3.18
+wcwidth==0.2.5
 Werkzeug==1.0.1
+zipp==3.1.0

backend/test_models.py

@@ -0,0 +1,13 @@
+from models import User, Todo
+
+
+def test_basic():
+    me = User.query.filter(User.name == 'me').first()
+    assert me.todos.count() == 2
+    assert me.todos.filter(Todo.complete == True).count() == 1
+    assert [todo.text for todo in me.todos.all()] == ['Taste JavaScript', 'Buy a unicorn']
+
+    other = User.query.filter(User.name == 'other').first()
+    assert other.todos.count() == 2
+    assert other.todos.filter(Todo.complete == True).count() == 1
+    assert [todo.text for todo in other.todos.all()] == ['This should be hidden', 'Secret task']

backend/test_schema.py

@@ -0,0 +1,239 @@
+from graphene.test import Client
+from schema import schema
+
+
+def test_basic_query():
+    client = Client(schema)
+    executed = client.execute('''
+query {
+  user (id: "VXNlcjox") {
+    name
+  }
+}
+''')
+    assert executed == {
+        'data': {
+            'user': {
+                'name': 'me',
+            },
+        },
+    }
+
+
+def test_all_users_query():
+    client = Client(schema)
+    executed = client.execute('''
+query {
+  allUsers {
+    edges {
+      node {
+        id
+        name
+      }
+    }
+  }
+}
+''')
+    assert executed == {
+        'data': {
+            'allUsers': {
+                'edges': [{
+                    'node': {
+                        'id': 'VXNlcjox',
+                        'name': 'me'
+                    }
+                }, {
+                    'node': {
+                        'id': 'VXNlcjoy',
+                        'name': 'other'
+                    }
+                }]
+            },
+        },
+    }
+
+
+def test_viewer_query():
+    client = Client(schema)
+    executed = client.execute('''
+query {
+  viewer {
+    totalCount
+    completedCount
+    todos {
+      edges {
+        node {
+          id
+          complete
+          text
+        }
+      }
+    }
+    anyTodos: todos (status: "any") {
+      edges {
+        node {
+          id
+          complete
+          text
+        }
+      }
+    }
+    completedTodos: todos (status: "completed") {
+      edges {
+        node {
+          id
+          complete
+          text
+        }
+      }
+    }
+  }
+}
+''')
+    completed_todo = {
+        'node': {
+            'id': 'VG9kbzox',
+            'complete': True,
+            'text': 'Taste JavaScript',
+        },
+    }
+    remaining_todo = {
+        'node': {
+            'id': 'VG9kbzoy',
+            'complete': False,
+            'text': 'Buy a unicorn',
+        },
+    }
+    assert executed == {
+        'data': {
+            'viewer': {
+                'totalCount': 2,
+                'completedCount': 1,
+                'todos': {
+                    'edges': [
+                        completed_todo,
+                        remaining_todo,
+                    ],
+                },
+                'anyTodos': {
+                    'edges': [
+                        completed_todo,
+                        remaining_todo,
+                    ],
+                },
+                'completedTodos': {
+                    'edges': [
+                        completed_todo,
+                    ],
+                },
+            },
+        },
+    }
+
+
+def test_mutation():
+    client = Client(schema)
+    executed = client.execute('''
+query {
+  user (id: "VXNlcjox") {
+    completedCount
+  }
+  todo (id: "VG9kbzox") {
+    complete
+    text
+  }
+}
+''')
+    assert executed == {
+        'data': {
+            'user': {
+                'completedCount': 1,
+            },
+            'todo': {
+                'complete': True,
+                'text': 'Taste JavaScript',
+            },
+        },
+    }
+
+    variables = {
+        'input': {
+            'id': 'VG9kbzox',
+            'complete': False,
+            'clientMutationId': 0,
+        }
+    }
+    executed = client.execute('''
+mutation ($input: ChangeTodoStatusInput!) {
+  changeTodoStatus(input: $input) {
+    todo { id complete }
+    viewer { id completedCount }
+  }
+}''', variable_values=variables)
+    assert executed == {
+        'data': {
+            'changeTodoStatus': {
+                'todo': {
+                    'id': 'VG9kbzox',
+                    'complete': False,
+                },
+                'viewer': {
+                    'id': 'VXNlcjox',
+                    'completedCount': 0,
+                },
+            },
+        },
+    }
+
+    executed = client.execute('''
+query {
+  user (id: "VXNlcjox") {
+    completedCount
+  }
+  todo (id: "VG9kbzox") {
+    complete
+    text
+  }
+}
+''')
+    assert executed == {
+        'data': {
+            'user': {
+                'completedCount': 0,
+            },
+            'todo': {
+                'complete': False,
+                'text': 'Taste JavaScript',
+            },
+        },
+    }
+
+    # revert changes
+    variables = {
+        'input': {
+            'id': 'VG9kbzox',
+            'complete': True,
+            'clientMutationId': 0,
+        },
+    }
+    executed = client.execute('''
+mutation ($input: ChangeTodoStatusInput!) {
+  changeTodoStatus(input: $input) {
+    todo { id complete }
+    viewer { id completedCount }
+  }
+}''', variable_values=variables)
+    assert executed == {
+        'data': {
+            'changeTodoStatus': {
+                'todo': {
+                    'id': 'VG9kbzox',
+                    'complete': True,
+                },
+                'viewer': {
+                    'id': 'VXNlcjox',
+                    'completedCount': 1,
+                },
+            },
+        },
+    }