first commit

README.md

@@ -0,0 +1,56 @@
+**Project**: inftools-cn
+
+**Purpose**: This repository contains a small helper container image and scripts to build and run a debugging/admin container for working with Docker and lightweight Kubernetes (k3d). The image includes `kubectl`, the Docker CLI, and `k3d` so you can create and administer a local k3d cluster from inside the container.
+
+**Key Files**:
+- `Dockerfile`: Builds the helper image (Debian Bookworm) with `kubectl`, `k3d`, and the Docker CLI.
+- `build.sh`: Ensures the `inftools-cn:latest` image exists, creates a user Docker network (`student-net`) if missing, and (when needed) runs `k3d cluster create mycluster` inside the helper container. It also edits the kubeconfig stored in the `mykube` Docker volume so the cluster API uses the load-balancer node.
+- `run.sh`: Launches an interactive shell in the helper container, mounting the Docker socket and the `mykube` volume.
+
+**Image / Resources**:
+- Image name: `inftools-cn:latest`
+- Docker network used: `student-net`
+- Docker volume used for kubeconfig: `mykube`
+
+**Requirements**:
+- Docker must be installed and the user must be able to access the Docker daemon (the scripts bind-mount `/var/run/docker.sock`).
+- Host can run containers and create networks/volumes.
+
+**Quick Usage**:
+
+- Build and create the k3d cluster (recommended):
+
+  ```bash
+  ./build.sh
+  ```
+
+- Start an interactive shell inside the helper container (uses the pre-built `inftools-cn:latest` image):
+
+  ```bash
+  ./run.sh
+  ```
+
+see [this demo](http://ascii.headshed.dev/a/dbfdZXIGo2wrvwn9ePsf9TFPs) of `build.sh` and `run.sh` on a debian bookworm OS
+
+<script src="http://ascii.headshed.dev/a/dbfdZXIGo2wrvwn9ePsf9TFPs.js" id="asciicast-dbfdZXIGo2wrvwn9ePsf9TFPs" async="true"></script>
+
+- Manual docker build/run (if you prefer):
+
+  ```bash
+  docker build -t inftools-cn:latest .
+  docker network create student-net    # if not present
+  docker run --rm -it --network student-net -v /var/run/docker.sock:/var/run/docker.sock -v mykube:/root/.kube inftools-cn:latest bash
+  ```
+
+**What `build.sh` does (summary)**:
+- Ensures the `inftools-cn:latest` image exists (builds it from `Dockerfile` if missing).
+- Creates `student-net` Docker network if it doesn't exist.
+- Runs the `k3d cluster create mycluster` command inside the helper container, captures the output to find the load-balancer node, and updates the kubeconfig in the `mykube` volume so the cluster API endpoint points to the LB node on port `6443`.
+
+**Security notes**:
+- The container mounts the host Docker socket (`/var/run/docker.sock`) into the container which grants the container broad control over the host Docker daemon. Only run this in trusted environments.
+
+**License**:
+- This project is licensed under the GNU General Public License v3.0 (GPL-3.0).
+- See the `LICENSE` file in this repository for the full license text.
+