# Docker Compose build properties

Applies to: Visual Studio Visual Studio for Mac Visual Studio Code

In addition to the properties that control individual Docker projects, described in Container Tools build properties, you can also customize how Visual Studio builds your Docker Compose projects by setting the Docker Compose properties that MSBuild uses to build your solution. You can also control how the Visual Studio debugger runs your Docker Compose apps by setting file labels in Docker Compose configuration files.

## How to set the MSBuild properties

To set the value of a property, edit the project file. For Docker Compose properties, this project file is the one with a .dcproj extension, unless otherwise indicated in the table in the next section. For example, suppose you want to specify to launch the browser when you start debugging. You can set the DockerLaunchAction property in the .dcproj project file as follows.

<PropertyGroup>
<DockerLaunchAction>LaunchBrowser</DockerLaunchAction>
</PropertyGroup>


You can add the property setting to an existing PropertyGroup element, or if there isn't one, create a new PropertyGroup element.

## Docker Compose MSBuild properties

The following table shows the MSBuild properties available for Docker Compose projects.

Property name Location Description Default value
AdditionalComposeFilePaths dcproj Specifies additional compose files in a semicolon-delimited list to be sent out to docker-compose.exe for all commands. Relative paths from the docker-compose project file (dcproj) are allowed. -
DockerComposeBaseFilePath dcproj Specifies the first part of the filenames of the docker-compose files, without the .yml extension. For example:
1. DockerComposeBaseFilePath = null/undefined: use the base file path docker-compose, and files will be named docker-compose.yml and docker-compose.override.yml.
2. DockerComposeBaseFilePath = mydockercompose: files will be named mydockercompose.yml and mydockercompose.override.yml.
3. DockerComposeBaseFilePath = ..\mydockercompose: files will be up one level.
docker-compose
DockerComposeBuildArguments dcproj Specifies the extra parameters to pass to the docker-compose build command. For example, --parallel --pull.
DockerComposeDownArguments dcproj Specifies the extra parameters to pass to the docker-compose down command. For example, --timeout 500. -
DockerComposeProjectName dcproj If specified, overrides the project name for a docker-compose project. "dockercompose" + auto-generated hash
DockerComposeProjectPath csproj or vbproj The relative path to the docker-compose project (dcproj) file. Set this property when publishing the service project to find the associated image build settings stored in the docker-compose.yml file. -
DockerComposeProjectsToIgnore dcproj Specifies projects to be ignored by docker-compose tools during debug. This property can be used for any project. File paths can be specified one of two ways:
1. Relative to dcproj. For example, <DockerComposeProjectsToIgnore>path\to\AngularProject1.csproj</DockerComposeProjectsToIgnore>.
2. Absolute paths.
Note: The paths should be separated by the delimiter character ;.
-
DockerComposeUpArguments dcproj Specifies the extra parameters to pass to the docker-compose up command. For example, --timeout 500. -
DockerDevelopmentMode dcproj Controls whether the user project is built in the container. The allowed values of Fast or Regular control which stages are built in a Dockerfile. The Debug configuration is Fast mode by default and Regular mode otherwise. Fast
DockerLaunchAction dcproj Specifies the launch action to perform on F5 or Ctrl+F5. Allowed values are None, LaunchBrowser, and LaunchWCFTestClient. None
DockerLaunchBrowser dcproj Indicates whether to launch the browser. Ignored if DockerLaunchAction is specified. False
DockerServiceName dcproj If DockerLaunchAction or DockerLaunchBrowser are specified, then DockerServiceName specifies which service referenced in the docker-compose file gets launched. -
DockerServiceUrl dcproj The URL to use when launching the browser. Valid replacement tokens are "{ServiceIPAddress}", "{ServicePort}", and "{Scheme}". For example: {Scheme}://{ServiceIPAddress}:{ServicePort} -
DockerTargetOS dcproj The target OS used when building the Docker image. -

## Example

If you change the location of the docker compose files, by setting DockerComposeBaseFilePath to a relative path, then you also need to make sure that the build context is changed so that it references the solution folder. For example, if your docker compose file is a folder called DockerComposeFiles, then docker compose file should set the build context to ".." or "../..", depending on where it is relative to the solution folder.

<?xml version="1.0" encoding="utf-8"?>
<Project ToolsVersion="15.0" Sdk="Microsoft.Docker.Sdk">
<PropertyGroup Label="Globals">
<ProjectVersion>2.1</ProjectVersion>
<DockerTargetOS>Windows</DockerTargetOS>
<ProjectGuid>154022c1-8014-4e9d-bd78-6ff46670ffa4</ProjectGuid>
<DockerLaunchAction>LaunchBrowser</DockerLaunchAction>
<DockerServiceName>webapplication1</DockerServiceName>
<DockerComposeBaseFilePath>DockerComposeFiles\mydockercompose</DockerComposeBaseFilePath>
</PropertyGroup>
<ItemGroup>
<None Include="DockerComposeFiles\mydockercompose.override.yml">
<DependentUpon>DockerComposeFiles\mydockercompose.yml</DependentUpon>
</None>
<None Include="DockerComposeFiles\mydockercompose.yml" />
<None Include=".dockerignore" />
</ItemGroup>
</Project>


The mydockercompose.yml file should look like this, with the build context set to the relative path of the solution folder (in this case, ..).

version: '3.4'

services:
webapplication1:
image: \${DOCKER_REGISTRY-}webapplication1
build:
context: ..
dockerfile: WebApplication1\Dockerfile


Note

DockerComposeBuildArguments, DockerComposeDownArguments, and DockerComposeUpArguments are new in Visual Studio 2019 version 16.3.

## Overriding Visual Studio's Docker Compose configuration

Typically docker-compose.override.yml is used to override certain settings in docker-compose.yml. Additionally, Visual Studio generates override files docker-compose.vs.debug.g,yml (for Fast mode) and docker-compose.vs.release.g.yml (for Regular mode) files with settings that are specific to running the application inside Visual Studio. You can override these Visual Studio settings by placing a file named docker-compose.vs.debug.yml (for Fast mode) or docker-compose.vs.release.yml (for Regular mode) in the same directory as your docker-compose.yml file. Right click the docker-compose project and select Open Folder in File Explorer , then use Add > Existing Item to add the file to your docker-compose project.

Tip

To find out the default values for any of the Visual Studio settings, look in the intermediate output directory (for example, obj/Docker) for docker-compose.vs.debug.g.yml or docker-compose.vs.release.g.yml. These files are generated by Visual Studio and should not be modified.

### Docker Compose file labels

In docker-compose.vs.debug.yml or docker-compose.vs.release.yml, you can define override-specific labels as follows:

services:
webapplication1:
labels:
com.microsoft.visualstudio.debuggee.workingdirectory: "C:\\my_app_folder"


Use double quotes around the values, as in the preceding example, and use the backslash as an escape character for backslashes in paths.

Label name Description
com.microsoft.visualstudio.debuggee.program The program launched when starting debugging. For .NET Core apps, this setting is typically dotnet.
com.microsoft.visualstudio.debuggee.arguments The arguments passed to the program when starting debugging. For .NET Core apps, these arguments are typically additional search paths for NuGet packages followed by the path to the project's output assembly.
com.microsoft.visualstudio.debuggee.workingdirectory The directory used as the starting directory when starting debugging. This setting is typically /app for Linux containers, or C:\app for Windows containers.
com.microsoft.visualstudio.debuggee.killprogram This command is used to stop the debuggee program that's running inside of the container (when necessary).
Label name Description
com.microsoft.visualstudio.debuggee.program The program launched when starting debugging. For .NET Core apps, this setting is typically dotnet.
com.microsoft.visualstudio.debuggee.arguments The arguments passed to the program when starting debugging. For .NET Core apps, these arguments are typically additional search paths for NuGet packages followed by the path to the project's output assembly.
com.microsoft.visualstudio.debuggee.workingdirectory The directory used as the starting directory when starting debugging. This setting is typically /app for Linux containers, or C:\app for Windows containers.
com.microsoft.visualstudio.debuggee.killprogram This command is used to stop the debuggee program that's running inside of the container (when necessary).
com.microsoft.visualstudio.debuggee.noattach.program The program launched when you use Start without debugging (Ctrl+F5) in an Azure Functions project that runs in an isolated process. Typically both F5 and Ctrl+F5 uses the same program, but if any project type like Azure Functions in an isolated process requires a different program than F5, then this will be used.
com.microsoft.visualstudio.debuggee.noattach.arguments The arguments passed to the program when you use Start without debugging (Ctrl+F5) in an Azure Functions project that runs in an isolated process.

### Customize the Docker build process

You can declare which stage to build in your Dockerfile by using the target setting in the build property. This override can be used in only the docker-compose.vs.debug.yml or docker-compose.vs.release.yml

services:
webapplication1:
build:
target: customStage
labels:
...


### Customize the app startup process

You can run a command or custom script before launching your app by using the entrypoint setting, and making it dependent on the DockerDevelopmentMode. For example, if you need to set up a certificate only in Fast mode by running update-ca-certificates, but not in Regular mode, you could add the following code in only docker-compose.vs.debug.yml:

services:
webapplication1:
entrypoint: "sh -c 'update-ca-certificates && tail -f /dev/null'"
labels:
...


## Next steps

For information on MSBuild properties generally, see MSBuild Properties.