# Containerization

<!-- ## Installation -->

## Genaral

## Usage

### Downloading container image

````{tabs}
```{code-tab} bash Podman
podman pull <IMAGE_NAME>:<IMAGE_TAG>
```

```{code-tab} bash Docker
docker pull <IMAGE_NAME>:<IMAGE_TAG>
```
````

`````{admonition} Example

To download `python` image version `3.12-slim`:

````{tabs}
```{code-tab} bash Podman
podman pull python:3.12-slim
```

```{code-tab} bash Docker
docker pull python:3.12-slim
```
````
`````


### Running a container

To run container based on image `<IMAGE_NAME>` with tag `<IMAGE_TAG>` execute:

````{tabs}
```{code-tab} bash Podman
podman run <IMAGE_NAME>:<IMAGE_TAG>
```

```{code-tab} bash Docker
docker run <IMAGE_NAME>:<IMAGE_TAG>
```
````

`````{admonition} Example

Run container based on `python` image version `3.12-slim`.

````{tabs}
```{code-tab} bash Podman
podman run python:3.12-slim
```

```{code-tab} bash Docker
docker run python:3.12-slim
```
````
`````

#### Name a container

You can specify container name with `--name` option:

````{tabs}
```{code-tab} bash Podman
podman run --name "<CONTAINER_NAME>" <IMAGE_NAME>:<IMAGE_TAG>
```

```{code-tab} bash Docker
docker run --name "<CONTAINER_NAME>" <IMAGE_NAME>:<IMAGE_TAG>
```
````

`````{admonition} Example

Run container based on `python` image version `3.12-slim` and name it `test_python_container`.

````{tabs}
```{code-tab} bash Podman
podman run --name test_python_container python:3.12-slim
```

```{code-tab} bash Docker
docker run --name test_python_containerpython:3.12-slim
```
````
`````

#### Execute a command inside a container

````{tabs}
```{code-tab} bash Podman
podman run <IMAGE_NAME>:<IMAGE_TAG> <CMD>
```

```{code-tab} bash Docker
docker run <IMAGE_NAME>:<IMAGE_TAG> <CMD>
```
````

`````{admonition} Example

Get version of python (run `python --verion`) inside the container:

````{tabs}
```{code-tab} bash Podman
podman run python:3.12-slim python --version
```

```{code-tab} bash Docker
docker run python:3.12-slim python --version
```
````
`````

#### Enter container's CLI (command line interface):

````{tabs}
```{code-tab} bash Podman
podman run -it <IMAGE_NAME>:<IMAGE_TAG> <CMD>
```

```{code-tab} bash Docker
docker run -it <IMAGE_NAME>:<IMAGE_TAG> <CMD>
```
````

`````{admonition} Example

enter `bash` CLI inside a `python` based container.

````{tabs}
```{code-tab} bash Podman
podman run -it python:3.12-slim bash
```

```{code-tab} bash Docker
docker run -it python:3.12-slim bash
```
````
`````

#### Expose container port:

````{tabs}
```{code-tab} bash Podman
podman run -p <HOST_PORT>:<CONTAINER_PORT> <IMAGE_NAME>:<IMAGE_TAG>
```

```{code-tab} bash Docker
docker run -p <HOST_PORT>:<CONTAINER_PORT> <IMAGE_NAME>:<IMAGE_TAG>
```
````

`````{admonition} Example

App inside container is running on port `8888`. If you want to access this app outside container with `localhost:8880`:

````{tabs}
```{code-tab} bash Podman
podman run -p 8880:8888 python:3.12-slim
```

```{code-tab} bash Docker
docker run -p 8880:8888 python:3.12-slim
```
````
`````


### Managing containers

#### Display (list) running containers

````{tabs}
```{code-tab} bash Podman
podman ps
```

```{code-tab} bash Docker
docker ps
```
````

#### Display all containers

This also displays exited (stopped) containers.

````{tabs}
```{code-tab} bash Podman
podman ps -a
```

```{code-tab} bash Docker
docker ps -a
```
````

### Managing images

#### Viewing locally available (downloaded) images

````{tabs}
```{code-tab} bash Podman
podman images 
```

```{code-tab} bash Docker
docker images 
```
````

## Building a container

To build a custom container image create a new folder create a `Dockerfile` file in that folder. (There can only be **one** `Dockerfile` file in any folder).

#### Build an image

### Dockerfile

## Compose

### Compose file

### Usage