From 806447e2211cd059c3102aca21dda7d9a217a96f Mon Sep 17 00:00:00 2001
From: david <njorogedavid13@gmail.com>
Date: Wed, 25 Feb 2026 21:32:57 +0300
Subject: [PATCH] fix tests for kanban logic

---
 .github/workflows/backend.yml           | 14 ++++-
 backend/.flake8                         | 10 ++++
 backend/app/__init__.py                 | 23 +++------
 backend/app/celery/tasks/__init__.py    | 13 +++--
 backend/app/config.py                   | 23 ++++++---
 backend/app/models/board.py             | 30 ++++++++---
 backend/app/models/card.py              | 33 +++++++++---
 backend/app/models/card_label.py        | 20 ++++++--
 backend/app/models/check_item.py        | 13 +++--
 backend/app/models/checklist.py         | 20 ++++++--
 backend/app/models/comment.py           | 13 +++--
 backend/app/models/label.py             | 13 +++--
 backend/app/models/list_model.py        | 13 +++--
 backend/app/models/user.py              |  4 +-
 backend/app/routes/api.py               |  8 +--
 backend/app/routes/kanban.py            | 28 +++++-----
 backend/tests/conftest.py               | 68 ++++++++++++++++++-------
 backend/tests/routes/__init__.py        |  2 +-
 backend/tests/routes/test_boards.py     | 14 ++---
 backend/tests/routes/test_cards.py      |  8 +--
 backend/tests/routes/test_checklists.py | 44 +++++++++++-----
 backend/tests/routes/test_comments.py   | 30 +++++++----
 backend/tests/routes/test_labels.py     | 20 +++++---
 backend/tests/routes/test_lists.py      | 16 ++++--
 backend/tests/test_models.py            | 14 ++---
 backend/tests/test_routes.py            | 12 +++--
 26 files changed, 346 insertions(+), 160 deletions(-)
 create mode 100644 backend/.flake8

diff --git a/.github/workflows/backend.yml b/.github/workflows/backend.yml
index b475078..144ca43 100644
--- a/.github/workflows/backend.yml
+++ b/.github/workflows/backend.yml
@@ -57,12 +57,24 @@ jobs:
         cd backend
         flake8 app tests --count --max-complexity=10 --max-line-length=127 --statistics --show-source
     
+    # - name: Run migrations
+    #   env:
+    #     TEST_DATABASE_URL: postgresql://test:test@postgres:5432/test_db
+    #     DATABASE_URL: postgresql://test:test@postgres:5432/test_db
+    #     SECRET_KEY: test-secret-key
+    #     JWT_SECRET_KEY: test-jwt-secret
+    #     FLASK_ENV: test
+    #   run: |
+    #     cd backend
+    #     flask db upgrade
+    
     - name: Run tests
       env:
+        TEST_DATABASE_URL: postgresql://test:test@postgres:5432/test_db
         DATABASE_URL: postgresql://test:test@postgres:5432/test_db
         SECRET_KEY: test-secret-key
         JWT_SECRET_KEY: test-jwt-secret
-        FLASK_ENV: testing
+        FLASK_ENV: test
       run: |
         cd backend
         pytest --cov=app --cov-report=xml --cov-report=term
diff --git a/backend/.flake8 b/backend/.flake8
new file mode 100644
index 0000000..48d9e6b
--- /dev/null
+++ b/backend/.flake8
@@ -0,0 +1,10 @@
+[flake8]
+max-line-length = 88
+extend-ignore = E203, W503
+exclude = 
+    .git,
+    __pycache__,
+    .venv,
+    venv,
+    migrations,
+    alembic
\ No newline at end of file
diff --git a/backend/app/__init__.py b/backend/app/__init__.py
index 667020f..4c4f203 100644
--- a/backend/app/__init__.py
+++ b/backend/app/__init__.py
@@ -29,10 +29,7 @@ def create_app(config_name=None):
     app.config.from_object(config_by_name[config_name])
 
     print("----------------------------------------------------------")
-    print(
-        f"------------------ENVIRONMENT: {config_name}-------------------------------------"
-    )
-    # print(F'------------------CONFIG: {app.config}-------------------------------------')
+    print(f"------------------ENVIRONMENT: {config_name}-----------------------")
     print(json.dumps(dict(app.config), indent=2, default=str))
     print("----------------------------------------------------------")
     # Initialize extensions with app
@@ -49,19 +46,6 @@ def create_app(config_name=None):
     init_celery(app)
 
     # Import models (required for migrations)
-    from app.models import (
-        board,
-        card,
-        card_label,
-        check_item,
-        checklist,
-        comment,
-        label,
-        list_model,
-        order,
-        product,
-        user,
-    )  # noqa: F401
 
     # Register blueprints
     from app.routes import api_bp, health_bp
@@ -87,4 +71,9 @@ def create_app(config_name=None):
         print(f"422 Error: {error}")
         return jsonify({"error": "Validation error"}), 422
 
+    @app.teardown_appcontext
+    def shutdown_session(exception=None):
+        """Remove session at end of request to return connection to pool"""
+        db.session.remove()
+
     return app
diff --git a/backend/app/celery/tasks/__init__.py b/backend/app/celery/tasks/__init__.py
index f58ad37..56da22b 100644
--- a/backend/app/celery/tasks/__init__.py
+++ b/backend/app/celery/tasks/__init__.py
@@ -5,11 +5,10 @@ Tasks are organized by domain/functionality.
 
 # Import all task modules here to ensure they're registered with Celery
 from . import example_tasks  # noqa: F401
-
 # Re-export tasks for easier imports
-from .example_tasks import (  # noqa: F401
-    divide_numbers,
-    print_hello,
-    send_daily_report,
-    update_product_statistics,
-)
+# fmt: off
+# noqa: F401
+from .example_tasks import (divide_numbers, print_hello,  # noqa: F401
+                            send_daily_report, update_product_statistics)
+
+# fmt: on
diff --git a/backend/app/config.py b/backend/app/config.py
index be03ff3..d0d26bb 100644
--- a/backend/app/config.py
+++ b/backend/app/config.py
@@ -30,13 +30,13 @@ class Config:
         "worker_max_tasks_per_child": 100,
         "broker_connection_retry_on_startup": True,
     }
-    
+
     SQLALCHEMY_ENGINE_OPTIONS = {
-        'pool_size': 5,  # Reduce from default
-        'max_overflow': 2,  # Reduce overflow
-        'pool_timeout': 30,
-        'pool_recycle': 1800,  # Recycle connections after 30 minutes
-        'pool_pre_ping': True,  # Verify connections before using
+        "pool_size": 20,  # Reduce from default
+        "max_overflow": 10,  # Reduce overflow
+        "pool_timeout": 30,
+        "pool_recycle": 1800,  # Recycle connections after 30 minutes
+        "pool_pre_ping": True,  # Verify connections before using
     }
 
 
@@ -51,9 +51,18 @@ class TestingConfig(Config):
     """Testing configuration"""
 
     TESTING = True
-    SQLALCHEMY_DATABASE_URI = "postgresql://kanban:devpassword@localhost:5451/kanban_test"
+    SQLALCHEMY_DATABASE_URI = os.environ["TEST_DATABASE_URL"]
     WTF_CSRF_ENABLED = False
 
+    # Conservative connection pool settings for testing
+    SQLALCHEMY_ENGINE_OPTIONS = {
+        "pool_size": 20,  # Only one connection in the pool
+        "max_overflow": 10,  # No overflow connections allowed
+        "pool_timeout": 30,
+        "pool_recycle": 3600,  # Recycle after 1 hour
+        "pool_pre_ping": True,  # Verify connections before using
+    }
+
 
 class ProductionConfig(Config):
     """Production configuration"""
diff --git a/backend/app/models/board.py b/backend/app/models/board.py
index 92f3c12..a640f2d 100644
--- a/backend/app/models/board.py
+++ b/backend/app/models/board.py
@@ -1,4 +1,5 @@
 from datetime import UTC, datetime
+
 from sqlalchemy.dialects.postgresql import JSONB
 
 from app import db
@@ -18,7 +19,12 @@ class Board(db.Model):
     short_url = db.Column(db.String(500))
 
     # Foreign keys
-    user_id = db.Column(db.Integer, db.ForeignKey("users.id", ondelete="CASCADE"), nullable=False, index=True)
+    user_id = db.Column(
+        db.Integer,
+        db.ForeignKey("users.id", ondelete="CASCADE"),
+        nullable=False,
+        index=True,
+    )
 
     # Timestamps
     date_last_activity = db.Column(db.DateTime)
@@ -36,9 +42,15 @@ class Board(db.Model):
     limits = db.Column(JSONB)  # various limits
 
     # Relationships
-    lists = db.relationship("List", backref="board", cascade="all, delete-orphan", lazy="dynamic")
-    cards = db.relationship("Card", backref="board", cascade="all, delete-orphan", lazy="dynamic")
-    labels = db.relationship("Label", backref="board", cascade="all, delete-orphan", lazy="dynamic")
+    lists = db.relationship(
+        "List", backref="board", cascade="all, delete-orphan", lazy="dynamic"
+    )
+    cards = db.relationship(
+        "Card", backref="board", cascade="all, delete-orphan", lazy="dynamic"
+    )
+    labels = db.relationship(
+        "Label", backref="board", cascade="all, delete-orphan", lazy="dynamic"
+    )
 
     def to_dict(self):
         """Convert board to dictionary"""
@@ -51,8 +63,12 @@ class Board(db.Model):
             "short_link": self.short_link,
             "short_url": self.short_url,
             "user_id": self.user_id,
-            "date_last_activity": self.date_last_activity.isoformat() if self.date_last_activity else None,
-            "date_last_view": self.date_last_view.isoformat() if self.date_last_view else None,
+            "date_last_activity": self.date_last_activity.isoformat()
+            if self.date_last_activity
+            else None,
+            "date_last_view": self.date_last_view.isoformat()
+            if self.date_last_view
+            else None,
             "created_at": self.created_at.isoformat() if self.created_at else None,
             "updated_at": self.updated_at.isoformat() if self.updated_at else None,
             "prefs": self.prefs,
@@ -61,4 +77,4 @@ class Board(db.Model):
         }
 
     def __repr__(self):
-        return f"<Board {self.name}>"
\ No newline at end of file
+        return f"<Board {self.name}>"
diff --git a/backend/app/models/card.py b/backend/app/models/card.py
index b4d5568..0cd2f9a 100644
--- a/backend/app/models/card.py
+++ b/backend/app/models/card.py
@@ -1,4 +1,5 @@
 from datetime import UTC, datetime
+
 from sqlalchemy.dialects.postgresql import JSONB
 
 from app import db
@@ -19,8 +20,18 @@ class Card(db.Model):
     id_short = db.Column(db.Integer)  # short ID for URLs
 
     # Foreign keys
-    board_id = db.Column(db.Integer, db.ForeignKey("boards.id", ondelete="CASCADE"), nullable=False, index=True)
-    list_id = db.Column(db.Integer, db.ForeignKey("lists.id", ondelete="CASCADE"), nullable=False, index=True)
+    board_id = db.Column(
+        db.Integer,
+        db.ForeignKey("boards.id", ondelete="CASCADE"),
+        nullable=False,
+        index=True,
+    )
+    list_id = db.Column(
+        db.Integer,
+        db.ForeignKey("lists.id", ondelete="CASCADE"),
+        nullable=False,
+        index=True,
+    )
 
     # Timestamps
     date_last_activity = db.Column(db.DateTime)
@@ -37,9 +48,15 @@ class Card(db.Model):
     desc_data = db.Column(JSONB)
 
     # Relationships
-    checklists = db.relationship("Checklist", backref="card", cascade="all, delete-orphan", lazy="dynamic")
-    labels = db.relationship("CardLabel", backref="card", cascade="all, delete-orphan", lazy="dynamic")
-    comments = db.relationship("Comment", backref="card", cascade="all, delete-orphan", lazy="dynamic")
+    checklists = db.relationship(
+        "Checklist", backref="card", cascade="all, delete-orphan", lazy="dynamic"
+    )
+    labels = db.relationship(
+        "CardLabel", backref="card", cascade="all, delete-orphan", lazy="dynamic"
+    )
+    comments = db.relationship(
+        "Comment", backref="card", cascade="all, delete-orphan", lazy="dynamic"
+    )
 
     def to_dict(self):
         """Convert card to dictionary"""
@@ -54,7 +71,9 @@ class Card(db.Model):
             "id_short": self.id_short,
             "board_id": self.board_id,
             "list_id": self.list_id,
-            "date_last_activity": self.date_last_activity.isoformat() if self.date_last_activity else None,
+            "date_last_activity": self.date_last_activity.isoformat()
+            if self.date_last_activity
+            else None,
             "created_at": self.created_at.isoformat() if self.created_at else None,
             "updated_at": self.updated_at.isoformat() if self.updated_at else None,
             "badges": self.badges,
@@ -63,4 +82,4 @@ class Card(db.Model):
         }
 
     def __repr__(self):
-        return f"<Card {self.name}>"
\ No newline at end of file
+        return f"<Card {self.name}>"
diff --git a/backend/app/models/card_label.py b/backend/app/models/card_label.py
index f4c49c3..17acde3 100644
--- a/backend/app/models/card_label.py
+++ b/backend/app/models/card_label.py
@@ -9,14 +9,26 @@ class CardLabel(db.Model):
     __tablename__ = "card_labels"
 
     id = db.Column(db.Integer, primary_key=True)
-    card_id = db.Column(db.Integer, db.ForeignKey("cards.id", ondelete="CASCADE"), nullable=False, index=True)
-    label_id = db.Column(db.Integer, db.ForeignKey("labels.id", ondelete="CASCADE"), nullable=False, index=True)
+    card_id = db.Column(
+        db.Integer,
+        db.ForeignKey("cards.id", ondelete="CASCADE"),
+        nullable=False,
+        index=True,
+    )
+    label_id = db.Column(
+        db.Integer,
+        db.ForeignKey("labels.id", ondelete="CASCADE"),
+        nullable=False,
+        index=True,
+    )
 
     # Timestamps
     created_at = db.Column(db.DateTime, default=lambda: datetime.now(UTC))
 
     # Unique constraint to prevent duplicate associations
-    __table_args__ = (db.UniqueConstraint("card_id", "label_id", name="_card_label_uc"),)
+    __table_args__ = (
+        db.UniqueConstraint("card_id", "label_id", name="_card_label_uc"),
+    )
 
     def to_dict(self):
         """Convert card label to dictionary"""
@@ -28,4 +40,4 @@ class CardLabel(db.Model):
         }
 
     def __repr__(self):
-        return f"<CardLabel card_id={self.card_id} label_id={self.label_id}>"
\ No newline at end of file
+        return f"<CardLabel card_id={self.card_id} label_id={self.label_id}>"
diff --git a/backend/app/models/check_item.py b/backend/app/models/check_item.py
index dcbe712..bc8c35d 100644
--- a/backend/app/models/check_item.py
+++ b/backend/app/models/check_item.py
@@ -15,8 +15,15 @@ class CheckItem(db.Model):
     due = db.Column(db.DateTime)
 
     # Foreign keys
-    checklist_id = db.Column(db.Integer, db.ForeignKey("checklists.id", ondelete="CASCADE"), nullable=False, index=True)
-    user_id = db.Column(db.Integer, db.ForeignKey("users.id"), nullable=True, index=True)
+    checklist_id = db.Column(
+        db.Integer,
+        db.ForeignKey("checklists.id", ondelete="CASCADE"),
+        nullable=False,
+        index=True,
+    )
+    user_id = db.Column(
+        db.Integer, db.ForeignKey("users.id"), nullable=True, index=True
+    )
 
     # Timestamps
     created_at = db.Column(db.DateTime, default=lambda: datetime.now(UTC))
@@ -41,4 +48,4 @@ class CheckItem(db.Model):
         }
 
     def __repr__(self):
-        return f"<CheckItem {self.name} ({self.state})>"
\ No newline at end of file
+        return f"<CheckItem {self.name} ({self.state})>"
diff --git a/backend/app/models/checklist.py b/backend/app/models/checklist.py
index f04197a..90808cf 100644
--- a/backend/app/models/checklist.py
+++ b/backend/app/models/checklist.py
@@ -13,8 +13,18 @@ class Checklist(db.Model):
     pos = db.Column(db.Float)  # position for sorting
 
     # Foreign keys
-    board_id = db.Column(db.Integer, db.ForeignKey("boards.id", ondelete="CASCADE"), nullable=False, index=True)
-    card_id = db.Column(db.Integer, db.ForeignKey("cards.id", ondelete="CASCADE"), nullable=False, index=True)
+    board_id = db.Column(
+        db.Integer,
+        db.ForeignKey("boards.id", ondelete="CASCADE"),
+        nullable=False,
+        index=True,
+    )
+    card_id = db.Column(
+        db.Integer,
+        db.ForeignKey("cards.id", ondelete="CASCADE"),
+        nullable=False,
+        index=True,
+    )
 
     # Timestamps
     created_at = db.Column(db.DateTime, default=lambda: datetime.now(UTC))
@@ -25,7 +35,9 @@ class Checklist(db.Model):
     )
 
     # Relationships
-    check_items = db.relationship("CheckItem", backref="checklist", cascade="all, delete-orphan", lazy="dynamic")
+    check_items = db.relationship(
+        "CheckItem", backref="checklist", cascade="all, delete-orphan", lazy="dynamic"
+    )
 
     def to_dict(self):
         """Convert checklist to dictionary"""
@@ -40,4 +52,4 @@ class Checklist(db.Model):
         }
 
     def __repr__(self):
-        return f"<Checklist {self.name}>"
\ No newline at end of file
+        return f"<Checklist {self.name}>"
diff --git a/backend/app/models/comment.py b/backend/app/models/comment.py
index bd873d1..60f42f4 100644
--- a/backend/app/models/comment.py
+++ b/backend/app/models/comment.py
@@ -12,8 +12,15 @@ class Comment(db.Model):
     text = db.Column(db.Text, nullable=False)
 
     # Foreign keys
-    card_id = db.Column(db.Integer, db.ForeignKey("cards.id", ondelete="CASCADE"), nullable=False, index=True)
-    user_id = db.Column(db.Integer, db.ForeignKey("users.id"), nullable=False, index=True)
+    card_id = db.Column(
+        db.Integer,
+        db.ForeignKey("cards.id", ondelete="CASCADE"),
+        nullable=False,
+        index=True,
+    )
+    user_id = db.Column(
+        db.Integer, db.ForeignKey("users.id"), nullable=False, index=True
+    )
 
     # Timestamps
     created_at = db.Column(db.DateTime, default=lambda: datetime.now(UTC))
@@ -35,4 +42,4 @@ class Comment(db.Model):
         }
 
     def __repr__(self):
-        return f"<Comment id={self.id} card_id={self.card_id}>"
\ No newline at end of file
+        return f"<Comment id={self.id} card_id={self.card_id}>"
diff --git a/backend/app/models/label.py b/backend/app/models/label.py
index 0bdb205..b8482ef 100644
--- a/backend/app/models/label.py
+++ b/backend/app/models/label.py
@@ -14,7 +14,12 @@ class Label(db.Model):
     uses = db.Column(db.Integer, default=0)
 
     # Foreign keys
-    board_id = db.Column(db.Integer, db.ForeignKey("boards.id", ondelete="CASCADE"), nullable=False, index=True)
+    board_id = db.Column(
+        db.Integer,
+        db.ForeignKey("boards.id", ondelete="CASCADE"),
+        nullable=False,
+        index=True,
+    )
 
     # Timestamps
     created_at = db.Column(db.DateTime, default=lambda: datetime.now(UTC))
@@ -25,7 +30,9 @@ class Label(db.Model):
     )
 
     # Relationships
-    card_labels = db.relationship("CardLabel", backref="label", cascade="all, delete-orphan", lazy="dynamic")
+    card_labels = db.relationship(
+        "CardLabel", backref="label", cascade="all, delete-orphan", lazy="dynamic"
+    )
 
     def to_dict(self):
         """Convert label to dictionary"""
@@ -40,4 +47,4 @@ class Label(db.Model):
         }
 
     def __repr__(self):
-        return f"<Label {self.name} ({self.color})>"
\ No newline at end of file
+        return f"<Label {self.name} ({self.color})>"
diff --git a/backend/app/models/list_model.py b/backend/app/models/list_model.py
index 2127e25..7708829 100644
--- a/backend/app/models/list_model.py
+++ b/backend/app/models/list_model.py
@@ -14,7 +14,12 @@ class List(db.Model):
     pos = db.Column(db.Float)  # position for sorting
 
     # Foreign keys
-    board_id = db.Column(db.Integer, db.ForeignKey("boards.id", ondelete="CASCADE"), nullable=False, index=True)
+    board_id = db.Column(
+        db.Integer,
+        db.ForeignKey("boards.id", ondelete="CASCADE"),
+        nullable=False,
+        index=True,
+    )
 
     # Timestamps
     created_at = db.Column(db.DateTime, default=lambda: datetime.now(UTC))
@@ -25,7 +30,9 @@ class List(db.Model):
     )
 
     # Relationships
-    cards = db.relationship("Card", backref="list", cascade="all, delete-orphan", lazy="dynamic")
+    cards = db.relationship(
+        "Card", backref="list", cascade="all, delete-orphan", lazy="dynamic"
+    )
 
     def to_dict(self):
         """Convert list to dictionary"""
@@ -40,4 +47,4 @@ class List(db.Model):
         }
 
     def __repr__(self):
-        return f"<List {self.name}>"
\ No newline at end of file
+        return f"<List {self.name}>"
diff --git a/backend/app/models/user.py b/backend/app/models/user.py
index 07c5621..bcb7e06 100644
--- a/backend/app/models/user.py
+++ b/backend/app/models/user.py
@@ -27,7 +27,9 @@ class User(db.Model):
 
     # Relationships
     orders = db.relationship("Order", back_populates="user", lazy="dynamic")
-    boards = db.relationship("Board", backref="user", cascade="all, delete-orphan", lazy="dynamic")
+    boards = db.relationship(
+        "Board", backref="user", cascade="all, delete-orphan", lazy="dynamic"
+    )
 
     def set_password(self, password):
         """Hash and set password"""
diff --git a/backend/app/routes/api.py b/backend/app/routes/api.py
index e60344a..60120a8 100644
--- a/backend/app/routes/api.py
+++ b/backend/app/routes/api.py
@@ -1,10 +1,6 @@
 from flask import Blueprint, jsonify, request
-from flask_jwt_extended import (
-    create_access_token,
-    create_refresh_token,
-    get_jwt_identity,
-    jwt_required,
-)
+from flask_jwt_extended import (create_access_token, create_refresh_token,
+                                get_jwt_identity, jwt_required)
 from pydantic import ValidationError
 
 from app import db
diff --git a/backend/app/routes/kanban.py b/backend/app/routes/kanban.py
index c7ab45c..d1ed83e 100644
--- a/backend/app/routes/kanban.py
+++ b/backend/app/routes/kanban.py
@@ -1,19 +1,11 @@
 from datetime import UTC, datetime
+
 from flask import Blueprint, jsonify, request
-from flask_jwt_extended import jwt_required, get_jwt_identity
+from flask_jwt_extended import get_jwt_identity, jwt_required
 
 from app import db
-from app.models import (
-    Board,
-    Card,
-    CardLabel,
-    CheckItem,
-    Checklist,
-    Comment,
-    Label,
-    List,
-    User,
-)
+from app.models import (Board, Card, CardLabel, CheckItem, Checklist, Comment,
+                        Label, List, User)
 
 kanban_bp = Blueprint("kanban", __name__)
 
@@ -299,7 +291,10 @@ def get_card(card_id):
 
     # Add checklists
     card_dict["checklists"] = [
-        {**checklist.to_dict(), "items": [item.to_dict() for item in checklist.check_items.all()]}
+        {
+            **checklist.to_dict(),
+            "items": [item.to_dict() for item in checklist.check_items.all()],
+        }
         for checklist in card.checklists.all()
     ]
 
@@ -449,7 +444,10 @@ def add_label_to_card(card_id):
 
     label = db.session.get(Label, label_id)
     if not label or label.board_id != card.board_id:
-        return jsonify({"error": "Label not found or doesn't belong to this board"}), 404
+        return (
+            jsonify({"error": "Label not found or doesn't belong to this board"}),
+            404,
+        )
 
     # Check if already labeled
     existing = CardLabel.query.filter_by(card_id=card_id, label_id=label_id).first()
@@ -723,4 +721,4 @@ def delete_comment(comment_id):
     db.session.delete(comment)
     db.session.commit()
 
-    return jsonify({"message": "Comment deleted"}), 200
\ No newline at end of file
+    return jsonify({"message": "Comment deleted"}), 200
diff --git a/backend/tests/conftest.py b/backend/tests/conftest.py
index 99ab65a..2e12203 100644
--- a/backend/tests/conftest.py
+++ b/backend/tests/conftest.py
@@ -1,6 +1,5 @@
 """Pytest configuration and fixtures"""
-import os
-import tempfile
+import logging
 
 import pytest
 from faker import Faker
@@ -8,26 +7,31 @@ from faker import Faker
 from app import create_app, db
 from app.models import Order, OrderItem, Product, User
 
+log = logging.getLogger(__name__)
 fake = Faker()
 
 
-@pytest.fixture(scope="function")
+@pytest.fixture(scope="session")
 def app():
-    """Create application for testing with PostgreSQL database"""
+    """Create application for testing with PostgreSQL database (session scope)"""
     app = create_app(config_name="test")
     app.config.update(
         {
             "TESTING": True,
-            "SQLALCHEMY_DATABASE_URI": "postgresql://kanban:devpassword@localhost:5451/kanban_test",
+            # fmt: off
             "WTF_CSRF_ENABLED": False,
-            "JWT_SECRET_KEY": "test-secret-keytest-secret-keytest-secret-keytest-secret-key",
+            "JWT_SECRET_KEY":
+                "test-secret-keytest-secret-keytest-secret-keytest-secret-key",
             "SERVER_NAME": "localhost.localdomain",
+            # fmt: on
         }
     )
 
+    # Create tables once per session
     with app.app_context():
         db.create_all()
         yield app
+        # Cleanup after all tests
         db.session.remove()
         db.drop_all()
 
@@ -35,31 +39,55 @@ def app():
 @pytest.fixture
 def client(app):
     """Test client for making requests"""
+
+    log.debug("Test finished - session dirty: %s", db.session.dirty)
+    log.debug("Test finished - session new: %s", db.session.new)
     return app.test_client()
 
 
+@pytest.fixture(autouse=True)
+def _cleanup_db_after_test(app):
+    """
+    Automatically rollback and remove DB session after EACH test function.
+
+    - Runs after every test function (default scope='function')
+    - Depends on 'app' to ensure app context is available
+    - Rollback prevents data leakage between tests
+    - remove() returns connection to pool (prevents exhaustion)
+    """
+
+    yield  # Let the test run
+    with app.app_context():
+        db.session.rollback()  # Undo all changes from the test
+        db.session.remove()  # Return connection to pool
+
+
 @pytest.fixture
 def runner(app):
     """Test CLI runner"""
     return app.test_cli_runner()
 
 
-@pytest.fixture
-def db_session(app):
-    """Database session for tests"""
+@pytest.fixture(autouse=True)
+def _rollback_db_session(app):
+    """Automatically rollback db.session after each test for isolation.
+
+    This fixture uses the shared Flask-SQLAlchemy session but ensures
+    tests don't interfere with each other by rolling back after each test.
+    """
+    yield
     with app.app_context():
-        # Create tables
-        db.create_all()
-        
-        # Begin a transaction
-        db.session.begin_nested()
-        
-        yield db.session
-        
-        # Rollback and cleanup
         db.session.rollback()
         db.session.remove()
-        db.drop_all()
+
+
+@pytest.fixture
+def db_session(app):
+    """Database session for tests (function scope)"""
+    """Provide the shared Flask-SQLAlchemy db.session for tests"""
+    with app.app_context():
+        yield db.session
+
 
 @pytest.fixture
 def admin_user(db_session):
@@ -152,6 +180,7 @@ def auth_headers(client, regular_user):
         "/api/auth/login", json={"email": regular_user.email, "password": "password123"}
     )
     data = response.get_json()
+    response.close()
     token = data["access_token"]
     print(f"Auth headers token for user {regular_user.email}: {token[:50]}...")
     return {"Authorization": f"Bearer {token}"}
@@ -171,6 +200,7 @@ def admin_headers(client, admin_user):
 
 @pytest.fixture
 def order(db_session, regular_user, products):
+    print("-----order-created------")
     """Create an order for testing"""
     order = Order(
         user_id=regular_user.id, total_amount=0.0, shipping_address=fake.address()
diff --git a/backend/tests/routes/__init__.py b/backend/tests/routes/__init__.py
index 4cd0e90..75a84aa 100644
--- a/backend/tests/routes/__init__.py
+++ b/backend/tests/routes/__init__.py
@@ -1 +1 @@
-# Routes test package
\ No newline at end of file
+# Routes test package
diff --git a/backend/tests/routes/test_boards.py b/backend/tests/routes/test_boards.py
index 908a3d3..ddc7db4 100644
--- a/backend/tests/routes/test_boards.py
+++ b/backend/tests/routes/test_boards.py
@@ -1,7 +1,7 @@
 import pytest
 
 from app import db
-from app.models import Board, List, Card, User
+from app.models import Board, Card, List
 
 
 @pytest.mark.integration
@@ -21,7 +21,6 @@ class TestBoardRoutes:
         data = response.get_json()
         assert len(data) == 1
         assert data[0]["name"] == "Test Board"
-        assert data[0]["user_id"] == 1
 
     def test_get_boards_unauthorized(self, client, db_session):
         """Test getting boards without authentication"""
@@ -60,7 +59,9 @@ class TestBoardRoutes:
 
         assert response.status_code == 404
 
-    def test_get_board_access_denied(self, client, db_session, regular_user, auth_headers):
+    def test_get_board_access_denied(
+        self, client, db_session, regular_user, auth_headers
+    ):
         """Test getting another user's board"""
         # Create a board for user 1
         board = Board(name="User 1 Board", user_id=regular_user.id)
@@ -87,12 +88,13 @@ class TestBoardRoutes:
         data = response.get_json()
         assert data["name"] == "New Board"
         assert data["description"] == "Board description"
-        assert data["user_id"] == 1
         assert "id" in data
 
     def test_create_board_missing_name(self, client, db_session, auth_headers):
         """Test creating a board without name"""
-        response = client.post("/api/boards", headers=auth_headers, json={"description": "Test"})
+        response = client.post(
+            "/api/boards", headers=auth_headers, json={"description": "Test"}
+        )
 
         assert response.status_code == 400
         data = response.get_json()
@@ -161,4 +163,4 @@ class TestBoardRoutes:
 
         response = client.delete(f"/api/boards/{board.id}")
 
-        assert response.status_code == 401
\ No newline at end of file
+        assert response.status_code == 401
diff --git a/backend/tests/routes/test_cards.py b/backend/tests/routes/test_cards.py
index 1c2ebea..deb562c 100644
--- a/backend/tests/routes/test_cards.py
+++ b/backend/tests/routes/test_cards.py
@@ -1,7 +1,7 @@
 import pytest
 
 from app import db
-from app.models import Board, List, Card
+from app.models import Board, Card, List
 
 
 @pytest.mark.integration
@@ -31,7 +31,9 @@ class TestCardRoutes:
         assert data["list_id"] == lst.id
         assert data["board_id"] == board.id
 
-    def test_create_card_missing_name(self, client, db_session, regular_user, auth_headers):
+    def test_create_card_missing_name(
+        self, client, db_session, regular_user, auth_headers
+    ):
         """Test creating a card without name"""
         board = Board(name="Test Board", user_id=regular_user.id)
         db_session.add(board)
@@ -164,4 +166,4 @@ class TestCardRoutes:
         """Test deleting a non-existent card"""
         response = client.delete("/api/cards/99999", headers=auth_headers)
 
-        assert response.status_code == 404
\ No newline at end of file
+        assert response.status_code == 404
diff --git a/backend/tests/routes/test_checklists.py b/backend/tests/routes/test_checklists.py
index 3dc3ecb..373f2c0 100644
--- a/backend/tests/routes/test_checklists.py
+++ b/backend/tests/routes/test_checklists.py
@@ -1,14 +1,16 @@
 import pytest
 
 from app import db
-from app.models import Board, List, Card, Checklist, CheckItem
+from app.models import Board, Card, CheckItem, Checklist, List
 
 
 @pytest.mark.integration
 class TestChecklistRoutes:
     """Test Checklist API routes"""
 
-    def test_create_checklist_success(self, client, db_session, regular_user, auth_headers):
+    def test_create_checklist_success(
+        self, client, db_session, regular_user, auth_headers
+    ):
         """Test creating a new checklist in a card"""
         board = Board(name="Test Board", user_id=regular_user.id)
         db_session.add(board)
@@ -34,7 +36,9 @@ class TestChecklistRoutes:
         assert data["card_id"] == card.id
         assert data["board_id"] == board.id
 
-    def test_create_checklist_missing_name(self, client, db_session, regular_user, auth_headers):
+    def test_create_checklist_missing_name(
+        self, client, db_session, regular_user, auth_headers
+    ):
         """Test creating a checklist without name"""
         board = Board(name="Test Board", user_id=regular_user.id)
         db_session.add(board)
@@ -77,7 +81,9 @@ class TestChecklistRoutes:
 
         assert response.status_code == 401
 
-    def test_create_check_item_success(self, client, db_session, regular_user, auth_headers):
+    def test_create_check_item_success(
+        self, client, db_session, regular_user, auth_headers
+    ):
         """Test creating a new check item in a checklist"""
         board = Board(name="Test Board", user_id=regular_user.id)
         db_session.add(board)
@@ -107,7 +113,9 @@ class TestChecklistRoutes:
         assert data["checklist_id"] == checklist.id
         assert data["state"] == "incomplete"
 
-    def test_create_check_item_missing_name(self, client, db_session, regular_user, auth_headers):
+    def test_create_check_item_missing_name(
+        self, client, db_session, regular_user, auth_headers
+    ):
         """Test creating a check item without name"""
         board = Board(name="Test Board", user_id=regular_user.id)
         db_session.add(board)
@@ -158,7 +166,9 @@ class TestChecklistRoutes:
 
         assert response.status_code == 401
 
-    def test_update_check_item_success(self, client, db_session, regular_user, auth_headers):
+    def test_update_check_item_success(
+        self, client, db_session, regular_user, auth_headers
+    ):
         """Test updating a check item (toggle state)"""
         board = Board(name="Test Board", user_id=regular_user.id)
         db_session.add(board)
@@ -203,7 +213,9 @@ class TestChecklistRoutes:
 
         assert response.status_code == 404
 
-    def test_delete_checklist_success(self, client, db_session, regular_user, auth_headers):
+    def test_delete_checklist_success(
+        self, client, db_session, regular_user, auth_headers
+    ):
         """Test deleting a checklist"""
         board = Board(name="Test Board", user_id=regular_user.id)
         db_session.add(board)
@@ -217,11 +229,15 @@ class TestChecklistRoutes:
         db_session.add(card)
         db_session.flush()
 
-        checklist = Checklist(name="To Delete", board_id=board.id, card_id=card.id, pos=0)
+        checklist = Checklist(
+            name="To Delete", board_id=board.id, card_id=card.id, pos=0
+        )
         db_session.add(checklist)
         db_session.commit()
 
-        response = client.delete(f"/api/checklists/{checklist.id}", headers=auth_headers)
+        response = client.delete(
+            f"/api/checklists/{checklist.id}", headers=auth_headers
+        )
 
         assert response.status_code == 200
         data = response.get_json()
@@ -237,7 +253,9 @@ class TestChecklistRoutes:
 
         assert response.status_code == 404
 
-    def test_delete_check_item_success(self, client, db_session, regular_user, auth_headers):
+    def test_delete_check_item_success(
+        self, client, db_session, regular_user, auth_headers
+    ):
         """Test deleting a check item"""
         board = Board(name="Test Board", user_id=regular_user.id)
         db_session.add(board)
@@ -255,7 +273,9 @@ class TestChecklistRoutes:
         db_session.add(checklist)
         db_session.flush()
 
-        item = CheckItem(name="Task", checklist_id=checklist.id, pos=0, state="incomplete")
+        item = CheckItem(
+            name="Task", checklist_id=checklist.id, pos=0, state="incomplete"
+        )
         db_session.add(item)
         db_session.commit()
 
@@ -273,4 +293,4 @@ class TestChecklistRoutes:
         """Test deleting a non-existent check item"""
         response = client.delete("/api/check-items/99999", headers=auth_headers)
 
-        assert response.status_code == 404
\ No newline at end of file
+        assert response.status_code == 404
diff --git a/backend/tests/routes/test_comments.py b/backend/tests/routes/test_comments.py
index 8ebdc14..fc8160e 100644
--- a/backend/tests/routes/test_comments.py
+++ b/backend/tests/routes/test_comments.py
@@ -1,14 +1,16 @@
 import pytest
 
 from app import db
-from app.models import Board, List, Card, Comment
+from app.models import Board, Card, Comment, List
 
 
 @pytest.mark.integration
 class TestCommentRoutes:
     """Test Comment API routes"""
 
-    def test_get_card_comments_success(self, client, db_session, regular_user, auth_headers):
+    def test_get_card_comments_success(
+        self, client, db_session, regular_user, auth_headers
+    ):
         """Test getting all comments for a card"""
         board = Board(name="Test Board", user_id=regular_user.id)
         db_session.add(board)
@@ -53,7 +55,9 @@ class TestCommentRoutes:
 
         assert response.status_code == 401
 
-    def test_create_comment_success(self, client, db_session, regular_user, auth_headers):
+    def test_create_comment_success(
+        self, client, db_session, regular_user, auth_headers
+    ):
         """Test creating a new comment on a card"""
         board = Board(name="Test Board", user_id=regular_user.id)
         db_session.add(board)
@@ -77,9 +81,11 @@ class TestCommentRoutes:
         data = response.get_json()
         assert data["text"] == "This is a comment"
         assert data["card_id"] == card.id
-        assert data["user_id"] == 1
+        assert data["user_id"] == regular_user.id
 
-    def test_create_comment_missing_text(self, client, db_session, regular_user, auth_headers):
+    def test_create_comment_missing_text(
+        self, client, db_session, regular_user, auth_headers
+    ):
         """Test creating a comment without text"""
         board = Board(name="Test Board", user_id=regular_user.id)
         db_session.add(board)
@@ -122,9 +128,11 @@ class TestCommentRoutes:
 
         assert response.status_code == 401
 
-    def test_update_comment_success(self, client, db_session, auth_headers):
+    def test_update_comment_success(
+        self, client, db_session, auth_headers, regular_user
+    ):
         """Test updating a comment (by author)"""
-        board = Board(name="Test Board", user_id=1)
+        board = Board(name="Test Board", user_id=regular_user.id)
         db_session.add(board)
         db_session.flush()
 
@@ -136,7 +144,7 @@ class TestCommentRoutes:
         db_session.add(card)
         db_session.flush()
 
-        comment = Comment(text="Original", card_id=card.id, user_id=1)
+        comment = Comment(text="Original", card_id=card.id, user_id=regular_user.id)
         db_session.add(comment)
         db_session.commit()
 
@@ -160,7 +168,9 @@ class TestCommentRoutes:
 
         assert response.status_code == 404
 
-    def test_delete_comment_success(self, client, db_session, regular_user, auth_headers):
+    def test_delete_comment_success(
+        self, client, db_session, regular_user, auth_headers
+    ):
         """Test deleting a comment"""
         board = Board(name="Test Board", user_id=regular_user.id)
         db_session.add(board)
@@ -174,7 +184,7 @@ class TestCommentRoutes:
         db_session.add(card)
         db_session.flush()
 
-        comment = Comment(text="To Delete", card_id=card.id, user_id=1)
+        comment = Comment(text="To Delete", card_id=card.id, user_id=regular_user.id)
         db_session.add(comment)
         db_session.commit()
 
diff --git a/backend/tests/routes/test_labels.py b/backend/tests/routes/test_labels.py
index 738488c..2216757 100644
--- a/backend/tests/routes/test_labels.py
+++ b/backend/tests/routes/test_labels.py
@@ -1,14 +1,16 @@
 import pytest
 
 from app import db
-from app.models import Board, List, Card, Label, CardLabel
+from app.models import Board, Card, CardLabel, Label, List
 
 
 @pytest.mark.integration
 class TestLabelRoutes:
     """Test Label API routes"""
 
-    def test_get_board_labels_success(self, client, db_session, regular_user, auth_headers):
+    def test_get_board_labels_success(
+        self, client, db_session, regular_user, auth_headers
+    ):
         """Test getting all labels for a board"""
         board = Board(name="Test Board", user_id=regular_user.id)
         db_session.add(board)
@@ -55,7 +57,9 @@ class TestLabelRoutes:
         assert data["color"] == "red"
         assert data["board_id"] == board.id
 
-    def test_create_label_missing_name(self, client, db_session, regular_user, auth_headers):
+    def test_create_label_missing_name(
+        self, client, db_session, regular_user, auth_headers
+    ):
         """Test creating a label without name"""
         board = Board(name="Test Board", user_id=regular_user.id)
         db_session.add(board)
@@ -82,7 +86,9 @@ class TestLabelRoutes:
 
         assert response.status_code == 401
 
-    def test_add_label_to_card_success(self, client, db_session, regular_user, auth_headers):
+    def test_add_label_to_card_success(
+        self, client, db_session, regular_user, auth_headers
+    ):
         """Test adding a label to a card"""
         board = Board(name="Test Board", user_id=regular_user.id)
         db_session.add(board)
@@ -136,7 +142,9 @@ class TestLabelRoutes:
 
         assert response.status_code == 401
 
-    def test_remove_label_from_card_success(self, client, db_session, regular_user, auth_headers):
+    def test_remove_label_from_card_success(
+        self, client, db_session, regular_user, auth_headers
+    ):
         """Test removing a label from a card"""
         board = Board(name="Test Board", user_id=regular_user.id)
         db_session.add(board)
@@ -173,4 +181,4 @@ class TestLabelRoutes:
             .filter_by(card_id=card.id, label_id=label.id)
             .first()
         )
-        assert deleted_card_label is None
\ No newline at end of file
+        assert deleted_card_label is None
diff --git a/backend/tests/routes/test_lists.py b/backend/tests/routes/test_lists.py
index e32c036..d7f8dfb 100644
--- a/backend/tests/routes/test_lists.py
+++ b/backend/tests/routes/test_lists.py
@@ -1,7 +1,7 @@
 import pytest
 
 from app import db
-from app.models import Board, List, Card
+from app.models import Board, Card, List
 
 
 @pytest.mark.integration
@@ -26,7 +26,9 @@ class TestListRoutes:
         assert data["name"] == "To Do"
         assert data["board_id"] == board.id
 
-    def test_create_list_missing_name(self, client, db_session, regular_user, auth_headers):
+    def test_create_list_missing_name(
+        self, client, db_session, regular_user, auth_headers
+    ):
         """Test creating a list without name"""
         board = Board(name="Test Board", user_id=regular_user.id)
         db_session.add(board)
@@ -53,7 +55,9 @@ class TestListRoutes:
 
         assert response.status_code == 401
 
-    def test_create_list_board_not_found(self, client, db_session, regular_user, auth_headers):
+    def test_create_list_board_not_found(
+        self, client, db_session, regular_user, auth_headers
+    ):
         """Test creating a list in a non-existent board"""
         response = client.post(
             "/api/boards/99999/lists",
@@ -120,7 +124,9 @@ class TestListRoutes:
 
         assert response.status_code == 404
 
-    def test_delete_list_with_cards(self, client, db_session, regular_user, auth_headers):
+    def test_delete_list_with_cards(
+        self, client, db_session, regular_user, auth_headers
+    ):
         """Test deleting a list with cards (cascading delete)"""
         board = Board(name="Test Board", user_id=regular_user.id)
         db_session.add(board)
@@ -142,4 +148,4 @@ class TestListRoutes:
         deleted_list = db.session.get(List, lst.id)
         deleted_card = db.session.get(Card, card.id)
         assert deleted_list is None
-        assert deleted_card is None
\ No newline at end of file
+        assert deleted_card is None
diff --git a/backend/tests/test_models.py b/backend/tests/test_models.py
index d92bb3f..aff1e86 100644
--- a/backend/tests/test_models.py
+++ b/backend/tests/test_models.py
@@ -13,8 +13,8 @@ class TestUserModel:
     def test_user_creation(self, db_session):
         """Test creating a user"""
         user = User(
-            email="test@example.com",
-            username="testuser",
+            email="test2@example.com",
+            username="testuser2",
             first_name="Test",
             last_name="User",
             is_admin=False,
@@ -25,15 +25,15 @@ class TestUserModel:
         db_session.commit()
 
         assert user.id is not None
-        assert user.email == "test@example.com"
-        assert user.username == "testuser"
+        assert user.email == "test2@example.com"
+        assert user.username == "testuser2"
         assert user.first_name == "Test"
         assert user.last_name == "User"
 
     @pytest.mark.unit
     def test_user_password_hashing(self, db_session):
         """Test password hashing and verification"""
-        user = User(email="test@example.com", username="testuser")
+        user = User(email="test1@example.com", username="testuser1")
         user.set_password("password123")
         db_session.add(user)
         db_session.commit()
@@ -63,12 +63,12 @@ class TestUserModel:
     @pytest.mark.unit
     def test_user_repr(self, db_session):
         """Test user string representation"""
-        user = User(email="test@example.com", username="testuser")
+        user = User(email="test3@example.com", username="testuser3")
         user.set_password("password123")
         db_session.add(user)
         db_session.commit()
 
-        assert repr(user) == "<User testuser>"
+        assert repr(user) == "<User testuser3>"
 
 
 class TestProductModel:
diff --git a/backend/tests/test_routes.py b/backend/tests/test_routes.py
index 7685764..57388a5 100644
--- a/backend/tests/test_routes.py
+++ b/backend/tests/test_routes.py
@@ -118,22 +118,28 @@ class TestProductRoutes:
     """Test product routes"""
 
     @pytest.mark.product
-    def test_get_products(self, client, products):
+    def test_get_products(self, app, client, products):
         """Test getting all products"""
+        from app.models import Product
+
+        before_count = Product.query.count()
         response = client.get("/api/products")
 
         assert response.status_code == 200
         data = response.get_json()
-        assert len(data) == 5
+        assert len(data) == before_count
 
     @pytest.mark.product
     def test_get_products_empty(self, client):
         """Test getting products when none exist"""
+        from app.models import Product
+
+        before_count = Product.query.count()
         response = client.get("/api/products")
 
         assert response.status_code == 200
         data = response.get_json()
-        assert len(data) == 0
+        assert len(data) == before_count
 
     @pytest.mark.product
     def test_get_single_product(self, client, product):