How to view and diagnose containers in Visual Studio
You can view what's going on inside the containers that host your app by using the Containers window. If you're used to using the command prompt to run Docker commands to view and diagnose what's going on with your containers, this window provides a more convenient way to monitor your containers without leaving the Visual Studio IDE.
The Containers window is currently available as a Preview extension that you can download for Visual Studio 2019.
View information about your containers
The Containers window opens automatically when you start a containerized .NET project. To view your containers in Visual Studio at any time, use Ctrl+Q to activate the Visual Studio Search box, and type
Containers and choose the first item. You can also open the Containers window from the main menu. Use the menu path View > Other Windows > Containers.
On the left side, you see the list of containers on your local machine. The containers associated with your solution are shown under Solution Containers. To the right, you see a pane with tabs for Environment, Ports, Logs, and Files.
You can easily customize where the Containers tool window is docked in Visual Studio. See Customizing window layouts in Visual Studio. By default, the Containers window is docked with the Watch window when the debugger is running.
View environment variables
The Environment tab shows the environment variables in the container. For your app's container, you can set these variables in many ways, for example, in the Dockerfile, in a .env file, or by using the -e option when you start a container using a Docker command.
Any changes to the environment variables aren't reflected in real time. Also, the environment variables in this tab are the system environment variables on the container, and do not reflect user environment variables local to the app.
View port mappings
On the Ports tab, you can check the port mappings that are in effect for your container.
Well-known ports are linked, so if there's content available on a port, you can click on the link to open the browser.
The Logs tab shows the results of the
docker logs command. By default, the tab shows stdout and stderr streams on a container, but you can configure the output. For details, see Docker logging. By default, the Logs tab streams the logs, but you can disable that by choosing the Stop button on the tab.
To clear the logs, use the Clear button on the Logs tab. To get all the logs, use the Refresh button.
Visual Studio automatically redirects stdout and stderr to the Output window, so containers started from Visual Studio (that is, the containers in the Solution Containers section) will not display logs in this tab; use the Output window instead.
View the filesystem
On the Files tab, you can view the container's filesystem, including the app folder that contains your project.
To open files in Visual Studio, browse to the file and double-click it, or right-click and choose Open. Visual Studio opens files in read-only mode.
Using the Files tab, you can view application logs such as IIS logs, configuration files, and other content files in your container's filesystem.
Start, stop, and remove containers
By default, the Containers window shows all containers on the machine that Docker manages. You can use the toolbar buttons to start, stop, or remove (delete) a container you no longer want. This list is dynamically updated as containers are created or removed.
Learn more about the Container Tools available in Visual Studio by reading the Container Tools Overview.