fixed all the postgreSQL issues

assignment2/README.md

@@ -27,29 +27,30 @@ This project deploys a full-stack weather web application to Kubernetes. It incl
 
 ## ☸️ Kubernetes Objects
 
-| Object Type            | File                 | Description                                                          |
+| Object Type            | File                   | Description                                                          |
-|------------------------|----------------------|----------------------------------------------------------------------|
+|------------------------|------------------------|----------------------------------------------------------------------|
-| `Namespace`            | (inside script)       | Isolates resources under `webapp-ns`                                 |
+| `Namespace`            | (inside script)        | Isolates resources under `webapp-ns`                                 |
-| `Deployment`           | `deployment.yaml`     | Manages frontend app                                                 |
+| `Deployment`           | `deployment.yaml`      | Manages frontend app                                                 |
-| `Deployment`           | `deployment-api.yaml` | Manages the Node.js API                                              |
+| `Deployment`           | `deployment-api.yaml`  | Manages the Node.js API                                              |
-| `StatefulSet`          | `statefulset.yaml`    | Manages PostgreSQL instance with persistent volume                   |
+| `StatefulSet`          | `statefulset.yaml`     | Manages PostgreSQL instance with persistent volume                   |
-| `PersistentVolume`     | `statefulset.yaml`    | Host-mounted volume for PostgreSQL data                              |
+| `PersistentVolume`     | `statefulset.yaml`     | Host-mounted volume for PostgreSQL data                              |
-| `PersistentVolumeClaim`| `statefulset.yaml`    | Requests storage for StatefulSet                                     |
+| `PersistentVolumeClaim`| `statefulset.yaml`     | Requests storage for StatefulSet                                     |
-| `Service`              | `service.yaml`        | Exposes frontend via NodePort                                        |
+| `Service`              | `service.yaml`         | Exposes frontend via NodePort                                        |
-| `Service`              | `deployment-api.yaml` | Exposes API via NodePort                                             |
+| `Service`              | `deployment-api.yaml`  | Exposes API via NodePort                                             |
-| `ConfigMap`            | Created by script     | Stores `init-db.sql` used to create the `weather_log` table          |
+| `Service`              | `postgres-service.yaml`| Internal ClusterIP service for PostgreSQL DNS resolution             |
+| `ConfigMap`            | `db-init-script`       | Stores the SQL init script for table creation                        |
 
 ---
 
 ##  Networking & Volumes
 
 ### Virtual Networks:
-- Kubernetes handles inter-service communication via internal DNS and `ClusterIP` services.
+- Kubernetes services provide internal DNS for `postgres` and `weather-api-service`.
-- Frontend and backend are externally reachable using `NodePort` services.
+- Frontend and API exposed externally using `NodePort` services.
 
 ### Volumes:
 - `PersistentVolume` and `PersistentVolumeClaim` ensure PostgreSQL data is retained.
-- `ConfigMap` mounts the SQL init script for PostgreSQL setup.
+- `ConfigMap` used to apply `init-db.sql` manually via `psql`.
 
 ---
 
@@ -57,18 +58,18 @@ This project deploys a full-stack weather web application to Kubernetes. It incl
 
 ### Frontend
 - Dockerfile uses `nginx:alpine`
-- Serves `weather.html` (renamed as `index.html` inside container)
+- Serves `weather.html`
 - Exposed on port `80`
 
 ### Node.js API
 - Built with Node.js 18
 - Listens on port `3000`
-- Connects to PostgreSQL using service DNS
+- Connects to PostgreSQL using service DNS `postgres`
-- Accepts POST requests at `/log` with weather data
+- Accepts POST requests at `/log`
 
 ### PostgreSQL
 - `postgres:15` with `weatheruser`, `weatherpass`, and `weatherdb`
-- Init script creates a `weather_log` table with a sample row
+- Table `weather_log` is created manually after StatefulSet starts
 
 ---
 
@@ -86,30 +87,62 @@ This project deploys a full-stack weather web application to Kubernetes. It incl
 ./start-app.sh
 ```
 
-### 3. View the App
+### 3. Manually Initialize the Database
+
+```bash
+kubectl exec -it -n webapp-ns statefulset/postgres -- psql -U weatheruser -d weatherdb
+```
+
+Paste this inside the prompt:
+
+```sql
+CREATE TABLE IF NOT EXISTS weather_log (
+    id SERIAL PRIMARY KEY,
+    city VARCHAR(100),
+    temperature DECIMAL(5,2),
+    description TEXT,
+    timestamp TIMESTAMP DEFAULT CURRENT_TIMESTAMP
+);
+```
+
+Exit with:
+```sql
+\q
+```
+
+### 4. View the App
 
 ```bash
 minikube service weather-service -n webapp-ns
 ```
 
-Or get the NodePort manually:
+Or manually:
 
 ```bash
-kubectl get svc -n webapp-ns
 minikube ip
+kubectl get svc -n webapp-ns
 ```
-
 Then open:
 ```
 http://<minikube-ip>:<frontend-nodeport>
 ```
 
-### 4. Use the App
+### 5. Use the App
-- Enter a city
+- Search for a city
-- Weather will be shown
+- Weather appears
-- Data is logged in PostgreSQL automatically
+- Weather data is logged via API to PostgreSQL
 
-### 5. Stop and Clean Up
+### 6. View Logged Data
+
+```bash
+kubectl exec -it -n webapp-ns statefulset/postgres -- psql -U weatheruser -d weatherdb
+```
+
+```sql
+SELECT * FROM weather_log ORDER BY timestamp DESC;
+```
+
+### 7. Stop and Clean Up
 
 ```bash
 ./stop-app.sh
@@ -120,8 +153,7 @@ http://<minikube-ip>:<frontend-nodeport>
 ##  API Key Setup
 
 - Register at [OpenWeatherMap](https://openweathermap.org/api)
-- Get your free API key
+- Replace the key in `weather.html`:
-- Replace the placeholder in `weather.html`:
 
 ```js
 const apiKey = "YOUR_API_KEY";
@@ -129,8 +161,10 @@ const apiKey = "YOUR_API_KEY";
 
 ---
 
-##  Conclusion
+## Conclusion
+
+- Frontend fetches real-time weather from OpenWeatherMap
+- Logs are POSTed to backend and stored in PostgreSQL
+
+---
 
-- Frontend calls OpenWeatherMap and logs data to your backend
-- PostgreSQL is prepped with a table to store queries
-- You can expand the API to serve saved data or stats

assignment2/deployment-api.yaml

@@ -13,9 +13,14 @@ spec:
       labels:
         app: weather-api
     spec:
+      initContainers:
+      - name: wait-for-postgres
+        image: busybox
+        command: ['sh', '-c', 'until nslookup postgres; do echo waiting for db; sleep 2; done']
       containers:
       - name: weather-api
         image: weather-api:latest
+        imagePullPolicy: IfNotPresent
         ports:
         - containerPort: 3000
 ---

assignment2/postgres-service.yaml

@@ -0,0 +1,13 @@
+apiVersion: v1
+kind: Service
+metadata:
+  name: postgres
+  namespace: webapp-ns
+spec:
+  selector:
+    app: postgres
+  ports:
+    - protocol: TCP
+      port: 5432
+      targetPort: 5432
+

assignment2/prepare-app.sh

@@ -1,7 +1,7 @@
 #!/bin/bash
 
 IMAGE_NAME=weather-frontend
-IMAGE_TAG=latest
+IMAGE_TAG=lates
 
 echo "🔧 Building Docker image: $IMAGE_NAME:$IMAGE_TAG"
 docker build -t $IMAGE_NAME:$IMAGE_TAG .

assignment2/server.js

@@ -8,7 +8,7 @@ const port = 3000;
 app.use(bodyParser.json());
 
 const pool = new Pool({
-  host: 'postgres-0.postgres.webapp-ns.svc.cluster.local',
+  host: 'postgres',
   user: 'weatheruser',
   password: 'weatherpass',
   database: 'weatherdb',

assignment2/statefulset.yaml

@@ -39,21 +39,6 @@ spec:
       labels:
         app: postgres
     spec:
-      initContainers:
-      - name: init-db
-        image: postgres:15
-        env:
-        - name: POSTGRES_USER
-          value: "weatheruser"
-        - name: POSTGRES_PASSWORD
-          value: "weatherpass"
-        - name: POSTGRES_DB
-          value: "weatherdb"
-        volumeMounts:
-        - name: init-script
-          mountPath: /docker-entrypoint-initdb.d
-        - name: postgres-storage
-          mountPath: /var/lib/postgresql/data
       containers:
       - name: postgres
         image: postgres:15
@@ -69,10 +54,6 @@ spec:
         volumeMounts:
         - name: postgres-storage
           mountPath: /var/lib/postgresql/data
-      volumes:
-      - name: init-script
-        configMap:
-          name: db-init-script
   volumeClaimTemplates:
   - metadata:
       name: postgres-storage