#!/bin/bash set -e echo "Preparing To-Do List Application for Kubernetes Deployment" # Create directory for application files mkdir -p ./app # Create index.html file cat > ./app/index.html << 'EOF' To-Do List

What should i do list (Reminder)

What needs to be done today

EOF # Create style.css file cat > ./app/style.css << 'EOF' body { font-family: "Helvetica Neue", sans-serif; background: linear-gradient(to bottom, #f7f7f7, #e1e1e1); display: flex; align-items: center; justify-content: center; min-height: 100vh; } .app-container { background-color: #ffffff; padding: 40px; border-radius: 20px; width: 100%; max-width: 500px; box-shadow: 0px 15px 20px rgba(0, 0, 0, 0.3); border: 1px solid #d9d9d9; } h1 { font-family: "Helvetica", sans-serif; text-align: center; margin-bottom: 20px; font-size: 30px; color: #4a4a4a; text-shadow: 0px 1px 2px rgba(0, 0, 0, 0.2); } .subtitle { font-size: 16px; color: #6d6d72; text-align: center; margin-bottom: 20px; font-weight: 300; } form { display: flex; gap: 10px; margin-bottom: 20px; } #task-input { flex-grow: 1; padding: 15px; border-radius: 8px; border: 1px solid #c7c7c7; background-color: #f0f0f0; font-size: 18px; box-shadow: inset 1px 1px 3px rgba(0, 0, 0, 0.1); } form button { padding: 15px 25px; border: none; background: linear-gradient(to bottom, #4da6ff, #0066cc); color: #ffffff; border-radius: 12px; cursor: pointer; font-weight: bold; text-shadow: 0px -1px 1px rgba(0, 0, 0, 0.3); box-shadow: 0px 5px 8px rgba(0, 0, 0, 0.2); transition: all 0.2s ease; font-size: 16px; } form button:active { background: linear-gradient(to bottom, #0066cc, #4da6ff); box-shadow: 0px 2px 5px rgba(0, 0, 0, 0.2); transform: translateY(2px); } .filter-buttons { display: flex; justify-content: space-around; margin: 20px 0; } .filter { background: linear-gradient(to bottom, #e6e6e6, #d1d1d1); border: 1px solid #c3c3c3; padding: 10px 20px; color: #4a4a4a; border-radius: 12px; cursor: pointer; font-weight: bold; text-shadow: 0px 1px 1px rgba(255, 255, 255, 0.6); box-shadow: 0px 3px 5px rgba(0, 0, 0, 0.15); transition: all 0.2s ease; font-size: 16px; } .filter.active, .filter:hover { background: linear-gradient(to bottom, #4da6ff, #0066cc); color: #ffffff; } #task-list { list-style: none; max-height: 400px; overflow-y: auto; padding: 10px 0; background-color: #ffffff; border-radius: 8px; border: 1px solid #e2e2e2; } .task-item { padding: 15px; border-radius: 10px; background-color: #ffffff; margin-bottom: 10px; box-shadow: 0 2px 5px rgba(0, 0, 0, 0.1); transition: background 0.3s ease; display: flex; justify-content: space-between; align-items: center; } .task-item:hover { background: linear-gradient(to bottom, #4da6ff, #0066cc); color: #ffffff; } .task-item.completed { text-decoration: line-through; color: #a09b8d; } .task-actions { display: flex; gap: 15px; } .task-actions button { background: none; border: none; cursor: pointer; font-size: 1.5em; } .task-actions button.complete-btn { color: #60a36e; text-shadow: 0px 1px 1px rgba(0, 0, 0, 0.2); } .task-actions button.delete-btn { color: #d9534f; text-shadow: 0px 1px 1px rgba(0, 0, 0, 0.2); } EOF # Create script.js file cat > ./app/script.js << 'EOF' // Получение элементов из HTML const taskForm = document.getElementById("task-form"); const taskInput = document.getElementById("task-input"); const taskList = document.getElementById("task-list"); const filterButtons = document.querySelectorAll(".filter"); // Загрузка задач из LocalStorage let tasks = JSON.parse(localStorage.getItem("tasks")) || []; // Переменная для отслеживания перетаскиваемой задачи let draggedTaskIndex = null; // Функция для отображения задач function displayTasks(filter = "all") { taskList.innerHTML = ""; const filteredTasks = tasks.filter(task => filter === "all" || (filter === "active" && !task.completed) || (filter === "completed" && task.completed) ); filteredTasks.forEach((task, index) => { const taskItem = document.createElement("li"); taskItem.classList.add("task-item"); taskItem.draggable = true; // Сделать элемент перетаскиваемым if (task.completed) taskItem.classList.add("completed"); taskItem.innerHTML = ` ${task.text}

`; // Добавление событий для drag-and-drop taskItem.addEventListener("dragstart", () => handleDragStart(index)); taskItem.addEventListener("dragover", (e) => handleDragOver(e)); taskItem.addEventListener("drop", () => handleDrop(index)); taskItem.addEventListener("dragend", handleDragEnd); taskList.appendChild(taskItem); }); } // Обработчик начала перетаскивания function handleDragStart(index) { draggedTaskIndex = index; } // Обработчик, предотвращающий действия по умолчанию (нужен для drop) function handleDragOver(e) { e.preventDefault(); } // Обработчик окончания перетаскивания function handleDrop(index) { if (draggedTaskIndex !== null && draggedTaskIndex !== index) { const draggedTask = tasks[draggedTaskIndex]; tasks.splice(draggedTaskIndex, 1); tasks.splice(index, 0, draggedTask); saveTasks(); displayTasks(); } draggedTaskIndex = null; } // Обработчик окончания перетаскивания function handleDragEnd() { draggedTaskIndex = null; } // Добавление новой задачи taskForm.addEventListener("submit", (e) => { e.preventDefault(); const taskText = taskInput.value.trim(); if (!taskText) return; const newTask = { id: Date.now().toString(), text: taskText, completed: false }; tasks.push(newTask); saveTasks(); displayTasks(); taskInput.value = ""; }); // Переключение статуса задачи на выполнено function toggleComplete(taskId) { tasks = tasks.map(task => task.id === taskId ? { ...task, completed: !task.completed } : task ); saveTasks(); displayTasks(); } // Удаление задачи function deleteTask(taskId) { tasks = tasks.filter(task => task.id !== taskId); saveTasks(); displayTasks(); } // Сохранение задач в LocalStorage function saveTasks() { localStorage.setItem("tasks", JSON.stringify(tasks)); console.log("Tasks saved:", tasks); } // Добавление события для фильтров filterButtons.forEach(button => { button.addEventListener("click", () => { filterButtons.forEach(btn => btn.classList.remove("active")); button.classList.add("active"); displayTasks(button.dataset.filter); }); }); // Инициализация displayTasks(); EOF # Create Dockerfile cat > ./Dockerfile << 'EOF' FROM nginx:alpine # Create app directory WORKDIR /usr/share/nginx/html # Copy application files COPY ./app/index.html . COPY ./app/style.css . COPY ./app/script.js . # Expose port EXPOSE 80 # Start nginx server CMD ["nginx", "-g", "daemon off;"] EOF # Create Kubernetes namespace file cat > ./namespace.yaml << 'EOF' apiVersion: v1 kind: Namespace metadata: name: todo-app-ns labels: app: todo-app EOF # Create deployment file cat > ./deployment.yaml << 'EOF' apiVersion: apps/v1 kind: Deployment metadata: name: todo-web-app namespace: todo-app-ns labels: app: todo-web-app spec: replicas: 2 selector: matchLabels: app: todo-web-app template: metadata: labels: app: todo-web-app spec: containers: - name: todo-web-app image: todo-web-app:latest imagePullPolicy: IfNotPresent ports: - containerPort: 80 resources: limits: cpu: "500m" memory: "256Mi" requests: cpu: "100m" memory: "128Mi" EOF # Create service file cat > ./service.yaml << 'EOF' apiVersion: v1 kind: Service metadata: name: todo-web-service namespace: todo-app-ns spec: selector: app: todo-web-app ports: - port: 80 targetPort: 80 type: NodePort EOF # Create statefulset file cat > ./statefulset.yaml << 'EOF' # PersistentVolume for storing tasks data apiVersion: v1 kind: PersistentVolume metadata: name: todo-app-pv labels: type: local spec: storageClassName: manual capacity: storage: 1Gi accessModes: - ReadWriteOnce hostPath: path: "/mnt/data/todo-app" --- # PersistentVolumeClaim for the StatefulSet apiVersion: v1 kind: PersistentVolumeClaim metadata: name: todo-app-pvc namespace: todo-app-ns spec: storageClassName: manual accessModes: - ReadWriteOnce resources: requests: storage: 1Gi --- # StatefulSet for task data persistence apiVersion: apps/v1 kind: StatefulSet metadata: name: todo-data-manager namespace: todo-app-ns spec: serviceName: "todo-data-service" replicas: 1 selector: matchLabels: app: todo-data-manager template: metadata: labels: app: todo-data-manager spec: containers: - name: todo-data-manager image: redis:alpine ports: - containerPort: 6379 name: redis volumeMounts: - name: todo-data mountPath: /data resources: limits: cpu: "300m" memory: "256Mi" requests: cpu: "100m" memory: "128Mi" volumeClaimTemplates: - metadata: name: todo-data spec: accessModes: [ "ReadWriteOnce" ] storageClassName: manual resources: requests: storage: 1Gi --- # Service for StatefulSet apiVersion: v1 kind: Service metadata: name: todo-data-service namespace: todo-app-ns labels: app: todo-data-manager spec: ports: - port: 6379 name: redis clusterIP: None selector: app: todo-data-manager EOF # Create start app script cat > ./start-app.sh << 'EOF' #!/bin/bash set -e echo "Starting To-Do List Application in Kubernetes" # Apply namespace kubectl apply -f namespace.yaml # Apply PV, PVC, and StatefulSet kubectl apply -f statefulset.yaml # Apply deployment kubectl apply -f deployment.yaml # Apply service kubectl apply -f service.yaml echo "Waiting for the application to start..." sleep 5 # Get NodePort information NODE_PORT=$(kubectl get svc todo-web-service -n todo-app-ns -o jsonpath='{.spec.ports[0].nodePort}') echo "The To-Do List application is available at: http://localhost:$NODE_PORT" echo "Application started successfully!" EOF # Create stop app script cat > ./stop-app.sh << 'EOF' #!/bin/bash set -e echo "Stopping To-Do List Application in Kubernetes" # Delete service kubectl delete -f service.yaml # Delete deployment kubectl delete -f deployment.yaml # Delete StatefulSet, PVC, and PV kubectl delete -f statefulset.yaml # Delete namespace kubectl delete -f namespace.yaml echo "Application stopped successfully!" EOF # Create README.md cat > ./README.md << 'EOF' # To-Do List Application on Kubernetes ## Application Description This is a simple To-Do List web application that allows users to: - Add new tasks - Mark tasks as completed - Delete tasks - Filter tasks by their status (All, Active, Completed) - Reorder tasks using drag-and-drop functionality The application uses local storage to persist tasks and allows users to manage their daily tasks efficiently. ## Container Images Used 1. **todo-web-app:latest**: - Custom image based on nginx:alpine - Contains the static web files (HTML, CSS, JavaScript) for the To-Do List application - Serves the web interface on port 80 2. **redis:alpine**: - Official Redis image based on Alpine Linux - Used in the StatefulSet for data persistence - Stores task data on a persistent volume - Runs on port 6379 ## Kubernetes Objects 1. **Namespace** (`todo-app-ns`): - Isolates all the application resources in a dedicated namespace 2. **Deployment** (`todo-web-app`): - Manages the web application containers - Maintains 2 replicas for high availability - Defines resource limits and requests 3. **StatefulSet** (`todo-data-manager`): - Manages Redis instances for data persistence - Uses persistent storage to maintain task data - Ensures data consistency during pod restarts 4. **PersistentVolume** (`todo-app-pv`): - Provides storage resources for the application - Uses local storage on the host at `/mnt/data/todo-app` - 1GB capacity for storing task data 5. **PersistentVolumeClaim** (`todo-app-pvc`): - Claims storage from the PersistentVolume - Used by the StatefulSet for data persistence 6. **Services**: - `todo-web-service`: NodePort service exposing the web application - `todo-data-service`: Headless service for the StatefulSet ## Network and Volume Configuration ### Networks - The application components communicate within the Kubernetes cluster using services - `todo-web-service` exposes the web interface externally using NodePort - `todo-data-service` provides internal DNS-based service discovery for the StatefulSet ### Volumes - The application uses a persistent volume mounted at `/mnt/data/todo-app` on the host - This volume is mounted into the Redis container at `/data` to persist task data - The volume uses the `manual` storage class with ReadWriteOnce access mode ## Container Configuration ### Web Application Container - Based on nginx:alpine - Configured to serve static content from `/usr/share/nginx/html` - Resource limits: 500m CPU, 256Mi memory - Resource requests: 100m CPU, 128Mi memory ### Redis Container - Based on redis:alpine - Data directory mounted to persistent storage - Resource limits: 300m CPU, 256Mi memory - Resource requests: 100m CPU, 128Mi memory ## How to Use the Application ### Prerequisites - Kubernetes cluster (Minikube or similar) - kubectl configured to communicate with your cluster - Docker for building the application image ### Prepare the Application 1. Clone this repository 2. Run the preparation script: ``` chmod +x prepare-app.sh ./prepare-app.sh ``` ### Start the Application 1. Run the start script: ``` chmod +x start-app.sh ./start-app.sh ``` 2. The script will display the URL to access the application ### Stop the Application 1. Run the stop script: ``` chmod +x stop-app.sh ./stop-app.sh ``` ### Accessing the Web Interface 1. After starting the application, note the NodePort displayed in the terminal 2. Open your web browser and navigate to `http://localhost:` 3. You should see the To-Do List application interface 4. Start adding tasks, marking them as completed, or deleting them as needed ## Troubleshooting - If pods aren't starting, check the pod status: `kubectl get pods -n todo-app-ns` - For detailed pod issues: `kubectl describe pod -n todo-app-ns` - To view logs: `kubectl logs -n todo-app-ns` EOF # Build Docker image echo "Building Docker image for the web application..." docker build -t todo-web-app:latest . # Create the host directory for PersistentVolume echo "Creating directory for persistent data..." # Use mkdir without sudo for compatibility with GitBash/Windows mkdir -p /mnt/data/todo-app 2>/dev/null || { echo "Note: Could not create /mnt/data/todo-app directory directly." echo "If you're using Minikube, you may need to create this directory inside the Minikube VM." echo "You can do this by running: minikube ssh 'sudo mkdir -p /mnt/data/todo-app && sudo chmod 777 /mnt/data/todo-app'" } # Make scripts executable chmod +x start-app.sh stop-app.sh echo "Application preparation completed successfully!"