> ## Documentation Index
> Fetch the complete documentation index at: https://notes.kodekloud.com/llms.txt
> Use this file to discover all available pages before exploring further.
# DEMO Image Automation Controller Repository
> This tutorial demonstrates using Flux's ImageRepository to automate image tag fetching from Docker Hub.
In this tutorial, we’ll use Flux’s `ImageRepository` Custom Resource Definition (CRD) to connect to a Docker Hub repository and fetch image tags automatically. Flux provides three subcommands under `flux create image`: `policy`, `repository`, and `update`. We’ll focus on the **repository** subcommand to set up continuous image discovery and metadata polling.
## Overview of Flux Image Commands
| Subcommand | Purpose | Example |
| ---------- | ---------------------------------------------- | --------------------------------------------------------------- |
| policy | Define rules for selecting image tags | `flux create image policy my-policy --image nginx` |
| repository | Register an image source for Flux to scan | `flux create image repository my-repo --image nginx` |
| update | Manually bump image tags on Kubernetes objects | `flux create image update deployment/my-app --policy my-policy` |
## 1. Create an ImageRepository
First, verify the available options:
```bash theme={null}
root ~/block-buster/flux-clusters/dev-cluster main
➜ flux create image
policy repository update
```
Define an `ImageRepository` manifest that points to your Docker Hub image and polls it at a regular interval:
```yaml theme={null}
apiVersion: image.toolkit.fluxcd.io/v1beta2
kind: ImageRepository
metadata:
name: bb-app-image-repo
namespace: flux-system
spec:
image: docker.io/siddharth67/bb-app-flux-demo
interval: 10s
```
Make sure your Git repository includes the `flux-system` namespace and the Flux controllers are installed before applying this manifest.
You can export this manifest directly with the Flux CLI:
```bash theme={null}
root ~/block-buster/flux-clusters/dev-cluster main
➜ flux create image repository bb-app-image-repo \
--image docker.io/siddharth67/bb-app-flux-demo \
--interval 10s \
--export > bb-app-image-repo.yaml
```
Commit and push the YAML to your Git repository, then trigger reconciliation:
```bash theme={null}
➜ flux reconcile source git flux-system
✔ GitRepository annotated
✔ waiting for GitRepository reconciliation
✔ fetched revision main@sha1:dc9922e7f45b3bcd8d085e68766869b15a17919c
```
Verify the repository registration and initial scan:
```bash theme={null}
➜ flux get image all
NAME LAST SCAN SUSPENDED READY MESSAGE
imagerepository/bb-app-image-repo 2023-04-06T19:19:02+05:30 False True successful scan: found 1 tags
```
At this point, Flux has detected the `7.8.0` tag in your Docker Hub repository.
## 2. Update the Application and Push a New Tag
### 2.1 Modify the PHP Source
Open `bb-app-source/src/index.php` (and `level2.php`) and update the styling as well as the app version to **7.8.1**:
```php theme={null}
Pod Name |
". getenv("MY_POD_NAME") ." |
Pod IP |
". getenv("MY_POD_IP") ." |
Namespace |
". getenv("MY_POD_NAMESPACE") ." |
K8S Node |
". getenv("MY_NODE_NAME") ." |
App Version |
7.8.1 (minor color change) |
What’s New |
BugFix – HighScore is persisted |
";
?>
```
Be sure to update **all** source files (e.g., `level2.php`) to keep version consistency.
### 2.2 Build and Push the Docker Image
Ensure your `Dockerfile` includes the necessary PHP extensions and copies your application files:
```dockerfile theme={null}
FROM php:7.4-apache
RUN docker-php-ext-install mysqli
COPY highscore.php index.php level2.php /var/www/html/
COPY images /var/www/html/images
EXPOSE 80
```
Build and tag the new image version **7.8.1**:
```bash theme={null}
root ~/block-buster/flux-clusters/dev-cluster main
cd ../bb-app-source/src
➜ docker build -t siddharth67/bb-app-flux-demo:7.8.1 .
```
Push the updated image to Docker Hub:
```bash theme={null}
➜ docker push siddharth67/bb-app-flux-demo:7.8.1
```
After pushing, verify on Docker Hub that the `7.8.1` tag is available.
## 3. Flux Scans the New Tag
Trigger an immediate reconciliation for the `ImageRepository`:
```bash theme={null}
➜ flux reconcile image repository bb-app-image-repo
```
Re-run the `flux get image` command to confirm that two tags are now detected:
```bash theme={null}
➜ flux get image all
NAME LAST SCAN SUSPENDED READY MESSAGE
imagerepository/bb-app-image-repo 2023-04-06T19:23:30+05:30 False True successful scan: found 2 tags
```
Alternatively, inspect the resource via `kubectl`:
```bash theme={null}
kubectl -n flux-system get imagerepositories.image.toolkit.fluxcd.io bb-app-image-repo -o yaml
```
```yaml theme={null}
status:
lastScanResult:
latestTags:
- "7.8.1"
- "7.8.0"
tagCount: 2
```
Even though two tags exist, your Deployment is still running the old version:
```bash theme={null}
kubectl -n a-demo get deploy block-buster -o wide
```
```plaintext theme={null}
NAME READY UP-TO-DATE AVAILABLE AGE CONTAINERS IMAGES SELECTOR
block-buster 1/1 1 1 15m app siddharth67/bb-app-flux-demo:7.8.0 app=block-buster
```
## Next Steps
Automate tag selection and deployment by creating a Flux **ImagePolicy** that matches your versioning scheme (e.g., semver or regex). This will ensure your Kubernetes workload always uses the latest approved image.
***
## Links and References
* [Flux Image Automation](https://fluxcd.io/docs/components/image/)
* [Kubernetes API Reference](https://kubernetes.io/docs/reference/)
* [Docker Hub Repository](https://hub.docker.com/)
* [GitOps with Flux](https://fluxcd.io/)