# Tutorial 0: Getting Started
:::{admonition} Learning Objectives
* Confirm your setup is correct.
* How to edit files in the container.
* How to view the container's graphical shell.
* How to run a python script in the container.
:::


## Confirm Your Setup is Correct

---

TODO: git, cloned repo, docker and docker compose on PATH, container running.

::::{tab-set}

:::{tab-item} Linux
```console
$ git --version
$ docker --version
$ docker compose version
$ docker run hello-world
```
Expected output  
 ```console
  git version 2.50.0
  Docker version 29.5.1, build 123123123
  Docker Compose version 5.1.0
  Hello from Docker!
  ...
  ```
:::

:::{tab-item} windows
```console
$ git --version
$ docker --version
$ docker compose version
$ docker run hello-world
```
Expected output  
 ```console
  git version 2.50.0
  Docker version 29.5.1, build 123123123
  Docker Compose version 5.1.0
  Hello from Docker!
  ...
  ```
:::

::::

To start the `ros2-demo` container use the task "Start ROS 2 container".
```{figure} ../../_static/images/getting_started_vsc_task.png
:alt: placeholder
:width: 60%
:align: center
VSCodium task to launch container's openvscode-server.
```
Or run the command,
::::{tab-set}
:::{tab-item} Linux
```console
$ 
```
Expected output  
 ```console
  git version 2.50.0
  Docker version 29.5.1, build 123123123
  Docker Compose version 5.1.0
  Hello from Docker!
  ...
  ```
:::

:::{tab-item} windows
```console
$ git --version
$ docker --version
$ docker compose version
$ docker run hello-world
```
Expected output  
 ```console
  git version 2.50.0
  Docker version 29.5.1, build 123123123
  Docker Compose version 5.1.0
  Hello from Docker!
  ...
  ```
:::

::::

:::{note} The container `ros2-demo` must be running! 
For instructions on
starting/stopping the container see: [Using The ROS2 Demo
Container](../../setup/using_container.md). 
:::


## Editing Files in the Container
---

:::{caution}
The container filesystem is *ephemeral*. Only files in
/home/robot/ros2-vsc-demo/ will persist across container destruction/recreation.
If you save or edit files elsewhere in the container those changes will be lost
next time the container is destroyed or recreated![^1]
:::


There are N ways to edit files in the running container. Here we will show how
to connect to the
[openvscode-server](https://github.com/gitpod-io/openvscode-server) running in
the `ros2-demo` container[^openvscode-server]. Direct your browser to the
following URL:
:::{div} center-text
<http://localhost:8087>
:::
or click the "Open VNC remote in browser" task.
```{figure} ../../_static/images/getting_started_vsc_task.png
:alt: placeholder
:width: 60%
:align: center
VSCodium task to launch container's openvscode-server.
```



## Using the Container's Graphical Shell
---
To use the graphical shell (desktop environment) of the Ubuntu container we can direct our browser to:
:::{div} center-text
<http://localhost:6087>
:::
or click the "Open VNC remote in browser" task.
```{figure} ../../_static/images/getting_started_vnc_task.png
:alt: placeholder
:width: 60%
:align: center
VSCodium task to launch container's graphical shell.
```
:::{dropdown}
TODO: Video

:::

### Running graphical programs in the container
Try running a graphical program from either the VSC integrated terminal, or the
shell in the VNC view. Either will make a graphical window appear!

```console
$ rviz2
```

:::{dropdown}
A video of the same process:
 <div style="max-width: 100%; overflow-x: auto;">
  <video controls style="width: 100%; height: auto;" poster="">
    <source src="../../_static/videos/container_vnc_vsc_task_drive.webm" type="video/webm">
  </video>
</div> 


:::



[^1]: This might seem like a downside at first but having the file system this
    way allows us to trivially fix a broken environment by destroying and
    recreating a container from the same image many times.

[^openvscode-server]: This is a remotely accessible VSCode editor you can
    connect to using a browser. Fun fact, most of VSCodium is written in
    js/html/css.