Run dotnet new after install to prime cache for deb

Copy postinst to correct directory

Can only rely on env for get dotnet command

Print telemetry notice anyway

build/package/Installer.DEB.proj

@@ -10,7 +10,7 @@
                             TestDebuild;
                             BuildSdkDeb;
                             TestSdkDeb;"
-          Condition=" '$(OSName)' == 'ubuntu' " 
+          Condition=" '$(OSName)' == 'ubuntu' "
           Outputs="@(GeneratedInstallers)"/>
 
   <Target Name="BuildSdkDeb"
@@ -28,11 +28,11 @@
       <!-- Create layout: Binaries -->
       <Copy
         DestinationFiles="@(CLISdkFiles->'$(LayoutPackageRootDir)/sdk/%(RecursiveDir)%(Filename)%(Extension)')"
-        SourceFiles="@(CLISdkFiles)"       
+        SourceFiles="@(CLISdkFiles)"
         OverwriteReadOnlyFiles="True"
         SkipUnchangedFiles="False"
         UseHardlinksIfPossible="False" />
-      
+
       <!-- Create layout: Man Pages -->
       <Copy
         DestinationFiles="@(SdkDebManPageFiles->'$(LayoutDocsDir)/%(RecursiveDir)%(Filename)-$(SdkVersion)%(Extension)')"
@@ -41,13 +41,21 @@
         SkipUnchangedFiles="False"
         UseHardlinksIfPossible="False" />
 
+      <!-- Create layout: postinst -->
+      <Copy
+        DestinationFiles= "$(DebianPostinstFile)"
+        SourceFiles="$(DebianPostinstTemplateFile)"
+        OverwriteReadOnlyFiles="True"
+        SkipUnchangedFiles="False"
+        UseHardlinksIfPossible="False" />
+
       <!-- Create layout: Generate and Place debian_config.json -->
       <ReplaceFileContents
         InputFile="$(DebianConfigTemplateFile)"
         DestinationFile="$(DebianConfigJsonFile)"
         ReplacementItems="@(DebianConfigTokenValues)" />
 
-      <Chmod 
+      <Chmod
         Glob="$(PackageTool)"
         Mode="u+x" />
 
@@ -58,12 +66,12 @@
                      PackageName="$(SdkDebianPackageName)"
                      PackageVersion="$(SdkVersion)"
                      WorkingDirectory="$(DotnetDebToolDir)" />
-      
+
       <!-- Copy SDK package to output -->
       <ItemGroup>
         <GeneratedDebFiles Include="$(DotNetDebToolOutputDirectory)/*.deb" />
       </ItemGroup>
-  
+
       <Error Text="@(GeneratedDebFiles->Count()) .deb files generated." Condition="'@(GeneratedDebFiles->Count())' != 1" />
 
       <Copy
@@ -97,9 +105,9 @@
       <Exec Command="sudo dpkg -i $(SdkInstallerFile)" />
 
       <!-- Run E2E -->
-      <DotNetRestore ProjectPath="$(EndToEndTestProject)" 
-                     ToolPath="$(DebianInstalledDirectory)" /> 
- 
+      <DotNetRestore ProjectPath="$(EndToEndTestProject)"
+                     ToolPath="$(DebianInstalledDirectory)" />
+
       <DotNetTest ProjectPath="$(EndToEndTestProject)"
                   EnvironmentVariables="@(TestSdkDebTaskEnvironmentVariables)"
                   ToolPath="$(DebianInstalledDirectory)" />
@@ -158,11 +166,11 @@
 
   <Target Name="TestDebuild">
       <Message Text="Don't remove this" />
-      
+
       <!-- run Debuild -->
       <Exec Command="/usr/bin/env debuild -h" ContinueOnError="true">
           <Output TaskParameter="ExitCode" PropertyName="DebuildExitCode" />
-      </Exec>  
+      </Exec>
 
       <!-- Check if it returned 0 -->
       <PropertyGroup>

build/package/Installer.DEB.targets

@@ -75,6 +75,11 @@
       <DebianConfigJsonFile>$(LayoutDirectory)/debian_config.json</DebianConfigJsonFile>
     </PropertyGroup>
 
+    <PropertyGroup>
+      <DebianPostinstTemplateFile>$(RepoRoot)/packaging/deb/postinst</DebianPostinstTemplateFile>
+      <DebianPostinstFile>$(LayoutDirectory)/debian/postinst</DebianPostinstFile>
+    </PropertyGroup>
+
     <ItemGroup>
       <DebianConfigTokenValues Include="%SHARED_FRAMEWORK_DEBIAN_PACKAGE_NAME%">
         <ReplacementString>$(SharedFxDebianPackageName)</ReplacementString>

packaging/deb/postinst

@@ -1,3 +1,15 @@
 #!/usr/bin/env sh
 echo "This software may collect information about you and your use of the software, and send that to Microsoft."
 echo "Please visit http://aka.ms/dotnet-cli-eula for more information."
+
+# Run 'dotnet new' to trigger the first time experience to initialize the cache
+echo "Welcome to .NET Core!
+---------------------
+Learn more about .NET Core @ https://aka.ms/dotnet-docs. Use dotnet --help to see available commands or go to https://aka.ms/dotnet-cli-docs.
+
+Telemetry
+--------------
+The .NET Core tools collect usage data in order to improve your experience. The data is anonymous and does not include command-line arguments. The data is collected by Microsoft and shared with the community.
+You can opt out of telemetry by setting a DOTNET_CLI_TELEMETRY_OPTOUT environment variable to 1 using your favorite shell.
+You can read more about .NET Core tools telemetry @ https://aka.ms/dotnet-cli-telemetry."
+dotnet new > /dev/null 2>&1 || true