feat(build): container publish for image with dacpac and sqlpackage

- paird with video demo: https://youtu.be/NaCNs0OOUbM
- new build target PublishContainer will create a docker image that can be run to publish your project's dacpac to a target database via sqlpackage

Author: nmummau

.gitignore

@@ -340,7 +340,8 @@ ASALocalRun/
 healthchecksdb
 
 # Exclude tools folder
-src/MSBuild.Sdk.SqlProj/tools/
+src/MSBuild.Sdk.SqlProj/tools/*
+!src/MSBuild.Sdk.SqlProj/tools/container/
 
 # Exclude generated Dacpac's
 *.dacpac

src/MSBuild.Sdk.SqlProj/Sdk/Sdk.targets

@@ -310,4 +310,86 @@
     </ItemGroup>
     <Message Importance="Low" Text="CopyDacpacFiles: @(CopyDacpacFiles)" />
   </Target>
+
+  <!-- ===== Container publish (experimental) : configuration ===== -->
+  <PropertyGroup>
+    <!-- Container CLI to invoke (typically 'docker') -->
+    <ContainerRuntime>docker</ContainerRuntime>
+
+    <!-- Dockerfile that builds the publisher image (installs sqlpackage, copies dacpacs) -->
+    <ContainerDockerfile>$(MSBuildThisFileDirectory)..\tools\container\sqlpackage.Dockerfile</ContainerDockerfile>
+
+    <!-- Default image name and tag. Override name & tag in CI as needed.
+       Lowercased and trimmed to comply with Docker naming rules. -->
+    <ContainerImageName Condition="'$(ContainerImageName)'==''">$([System.String]::Copy('$(MSBuildProjectName)').ToLowerInvariant().Trim())-publisher</ContainerImageName>
+    <ContainerImageTag Condition="'$(ContainerImageTag)'==''">$([System.String]::Copy('$(Configuration)').ToLowerInvariant().Trim())</ContainerImageTag>
+
+    <!-- Passed to the Dockerfile as build-arg SQLPACKAGE_VERSION -->
+    <SqlPackageVersion>170.2.70</SqlPackageVersion>
+
+    <!-- Local staging area for the project dacpac and referenced dacpacs -->
+    <ContainerStagingDir>$(MSBuildProjectDirectory)\.container</ContainerStagingDir>
+    <ContainerDacpacName>$(MSBuildProjectName).dacpac</ContainerDacpacName>
+    <ContainerDacpacPath>$(ContainerStagingDir)\$(ContainerDacpacName)</ContainerDacpacPath>
+  </PropertyGroup>
+
+  <!-- ===== Container publish (experimental) : targets ===== -->
+
+  <!--
+    PrepareContainerDacpac
+    Purpose: Build and stage the project dacpac and place all referenced dacpacs next to it for convenience.
+    Runs after a successful Build
+    Guards: Fails fast if the dacpac or Dockerfile is missing.
+    Inputs: $(TargetPath) (built dacpac), @(IncludedDacpacReferenceFiles)
+    Outputs/Side effects: Recreates $(ContainerStagingDir), copies dacpac(s) into it.
+  -->
+  <Target Name="PrepareContainerDacpac"
+      DependsOnTargets="Build;ResolveDatabaseReferences">
+
+    <Error Condition="!Exists('$(TargetPath)')"
+           Text="DACPAC '$(TargetPath)' not found. Build failed." />
+    <Error Condition="!Exists('$(ContainerDockerfile)')"
+           Text="Dockerfile '$(ContainerDockerfile)' not found. Check ContainerDockerfile property." />
+
+    <!-- Reset staging area -->
+    <RemoveDir Directories="$(ContainerStagingDir)" Condition="Exists('$(ContainerStagingDir)')" />
+    <MakeDir Directories="$(ContainerStagingDir)" />
+
+    <!-- Copy the project dacpac to the known staging path -->
+    <Copy SourceFiles="$(TargetPath)"
+          DestinationFiles="$(ContainerDacpacPath)"
+          OverWriteReadOnlyFiles="true" />
+
+    <!-- Also stage all referenced dacpacs beside the project dacpac (useful for Docker COPY patterns) -->
+    <Copy SourceFiles="@(IncludedDacpacReferenceFiles)"
+          DestinationFolder="$(ContainerStagingDir)"
+          SkipUnchangedFiles="true" />
+  </Target>
+
+  <!--
+    PublishContainer
+    Purpose: Build the publisher container image from the staged dacpac(s).
+    Runs after PrepareContainerDacpac
+    Behavior: Executes '<runtime> build' with tag and SQLPACKAGE_VERSION build-arg.
+    Output: Local container image $(ContainerImageName):$(ContainerImageTag)
+  -->
+  <Target Name="PublishContainer"
+          DependsOnTargets="PrepareContainerDacpac">
+    <Message Text="Building container $(ContainerImageName):$(ContainerImageTag)"
+             Importance="high" />
+    <Exec Command='"$(ContainerRuntime)" build -f "$(ContainerDockerfile)" -t "$(ContainerImageName):$(ContainerImageTag)" --build-arg SQLPACKAGE_VERSION=$(SqlPackageVersion) --build-arg DACPAC_NAME=$(ContainerDacpacName) "$(MSBuildProjectDirectory)"'
+          IgnoreExitCode="false" />
+  </Target>
+
+  <!--
+    PushContainer
+    Pushes to the registry implied by ContainerImageName (e.g., 'ghcr.io/org/name').
+    Ensure you've run 'docker login' (or equivalent) for that registry first.
+  -->
+  <Target Name="PushContainer">
+    <Message Text="Pushing container $(ContainerImageName):$(ContainerImageTag)"
+             Importance="high" />
+    <Exec Command='"$(ContainerRuntime)" push "$(ContainerImageName):$(ContainerImageTag)"'
+          IgnoreExitCode="false" />
+  </Target>
 </Project>

src/MSBuild.Sdk.SqlProj/tools/container/sqlpackage.Dockerfile

@@ -0,0 +1,46 @@
+# Base image: ships with the SDK
+ARG BASE_IMAGE=mcr.microsoft.com/dotnet/runtime:8.0
+FROM ${BASE_IMAGE}
+ARG SQLPACKAGE_VERSION
+ARG DACPAC_NAME
+ENV DACPAC_NAME=${DACPAC_NAME}
+
+# Install sqlpackage dependencies and pull from NuGet
+# - Supports native (platform zip) and dotnet tool layouts
+# - Installs a stable wrapper in /usr/local/bin/sqlpackage
+RUN set -eux; \
+    apt-get update \
+ && apt-get install -y --no-install-recommends ca-certificates curl unzip \
+ && curl -L -o /tmp/sqlpackage.nupkg "https://globalcdn.nuget.org/packages/microsoft.sqlpackage.${SQLPACKAGE_VERSION}.nupkg" \
+ && mkdir -p /opt/sqlpackage-src /opt/sqlpackage \
+ && unzip -q /tmp/sqlpackage.nupkg -d /opt/sqlpackage-src \
+ && inner="$(find /opt/sqlpackage-src -type f -iname '*linux-x64*.zip' | head -n1 || true)" \
+ && if [ -n "$inner" ]; then \
+        unzip -q "$inner" -d /opt/sqlpackage; \
+    else \
+        cp -R /opt/sqlpackage-src/tools/*/any/* /opt/sqlpackage/; \
+    fi \
+ && printf '#!/usr/bin/env bash\nset -euo pipefail\nif [ -x /opt/sqlpackage/sqlpackage ]; then exec /opt/sqlpackage/sqlpackage "$@"; elif [ -f /opt/sqlpackage/sqlpackage.dll ]; then exec dotnet /opt/sqlpackage/sqlpackage.dll "$@"; else echo "sqlpackage not found"; exit 127; fi\n' > /usr/local/bin/sqlpackage \
+ && chmod +x /usr/local/bin/sqlpackage \
+ && rm -rf /var/lib/apt/lists/* /tmp/* /opt/sqlpackage-src \
+ # Create entrypoint wrapper as root:
+ # - Bakes in `-Action:Publish` and `-SourceFile:/work/$DACPAC_NAME`
+ # - Forwards user-supplied args to sqlpackage
+ && install -d /usr/local/bin \
+ && printf '%s\n' \
+      '#!/usr/bin/env bash' \
+      'set -euo pipefail' \
+      'exec sqlpackage -Action:Publish -SourceFile:/work/"${DACPAC_NAME}" "$@"' \
+   | tee /usr/local/bin/docker-entrypoint >/dev/null \
+ && chmod +x /usr/local/bin/docker-entrypoint
+
+# Staging: the SDK copies all dacpacs into /work at build time
+WORKDIR /work
+COPY ./.container/*.dacpac /work/
+
+# Drop privileges to a non-root user
+RUN useradd -m runner
+USER runner
+
+# Exec-form ENTRYPOINT for proper signal handling and linter compliance
+ENTRYPOINT ["/usr/local/bin/docker-entrypoint"]