Initial commit

Signed-off-by: mikesir87 <mikesir87@gmail.com>

Imported from dockersamples/101-tutorial, removed other languages
for now, and replaced PWD references with Docker Desktop.

docs/tutorial/updating-our-app/index.md

@@ -0,0 +1,114 @@
+
+As a small feature request, we've been asked by the product team to
+change the "empty text" when we don't have any todo list items. They
+would like to transition it to the following:
+
+> You have no todo items yet! Add one above!
+
+Pretty simple, right? Let's make the change.
+
+## Updating our Source Code
+
+1. In the `src/static/js/app.js` file, update line 56 to use the new empty text.
+
+    ```diff
+    -                <p className="text-center">No items yet! Add one above!</p>
+    +                <p className="text-center">You have no todo items yet! Add one above!</p>
+    ```
+
+1. Let's build our updated version of the image, using the same command we used before.
+
+    ```bash
+    docker build -t getting-started .
+    ```
+
+1. Let's start a new container using the updated code.
+
+    ```bash
+    docker run -dp 3000:3000 getting-started
+    ```
+
+**Uh oh!** You probably saw an error like this (the IDs will be different):
+
+```bash
+docker: Error response from daemon: driver failed programming external connectivity on endpoint laughing_burnell 
+(bb242b2ca4d67eba76e79474fb36bb5125708ebdabd7f45c8eaf16caaabde9dd): Bind for 0.0.0.0:3000 failed: port is already allocated.
+```
+
+So, what happened? We aren't able to start the new container because our old container is still
+running. The reason this is a problem is because that container is using the host's port 3000 and
+only one process on the machine (containers included) can listen to a specific port. To fix this, 
+we need to remove the old container.
+
+
+## Replacing our Old Container
+
+To remove a container, it first needs to be stopped. Once it has stopped, it can be removed. We have two
+ways that we can remove the old container. Feel free to choose the path that you're most comfortable with.
+
+
+### Removing a container using the CLI
+
+1. Get the ID of the container by using the `docker ps` command.
+
+    ```bash
+    docker ps
+    ```
+
+1. Use the `docker stop` command to stop the container.
+
+    ```bash
+    # Swap out <the-container-id> with the ID from docker ps
+    docker stop <the-container-id>
+    ```
+
+1. Once the container has stopped, you can remove it by using the `docker rm` command.
+
+    ```bash
+    docker rm <the-container-id>
+    ```
+
+!!! info "Pro tip"
+    You can stop and remove a container in a single command by adding the "force" flag
+    to the `docker rm` command. For example: `docker rm -f <the-container-id>`
+
+### Removing a container using the Docker Dashboard
+
+If you open the Docker dashboard, you can remove a container with two clicks! It's certainly
+much easier than having to look up the container ID and remove it.
+
+1. With the dashboard opened, hover over the app container and you'll see a collection of action
+    buttons appear on the right.
+
+1. Click on the trash can icon to delete the container. 
+
+1. Confirm the removal and you're done!
+
+![Docker Dashboard - removing a container](dashboard-removing-container.png)
+
+
+### Starting our updated app container
+
+1. Now, start your updated app.
+
+    ```bash
+    docker run -dp 3000:3000 getting-started
+    ```
+
+1. Refresh your browser on [http://localhost:3000](http://localhost:3000) and you should see your updated help text!
+
+![Updated application with updated empty text](todo-list-updated-empty-text.png){: style="width:55%" }
+{: .text-center }
+
+
+
+## Recap
+
+While we were able to build an update, there were two things you might have noticed:
+
+- All of the existing items in our todo list are gone! That's not a very good app! We'll talk about that
+shortly.
+- There were _a lot_ of steps involved for such a small change. In an upcoming section, we'll talk about 
+how to see code updates without needing to rebuild and start a new container every time we make a change.
+
+Before talking about persistence, we'll quickly see how to share these images with others.