Is it possible to publish only certain appsettings.json in .NetCore application

Question

I have 4 appsettings.json in my .NetCore application:

• appsettings.json
• appsettings.Development.json
• appsettings.Test.json
• appsettings.Production.json

All of appsettings has Do not copy property, but I notice when publishing the application, all of appsettings files are copied over to publish folder. For example, appsettings.Production.json is copied to publish folder even I am publishing using Test environment.

It doesn't hurt but I want to know whether is it possible to copy just appsettings.json and appsettings.Test.json when publishing using Test environment?

Answer 1

Finally, the trick is to use <Content Remove=""> for appsettings.json.

I updated my .csproj to use conditional constructor to switch between different environments. Here is what it looks like:

<ItemGroup>
  <!-- Default behaviour here -->
  <None Update="other_files">
      <CopyToOutputDirectory>Always</CopyToOutputDirectory>
  </None>
</ItemGroup> 
<Choose>
  <When Condition=" '$(EnvironmentName)'=='Test' ">
    <ItemGroup>
      <Content Remove="appsettings.Development.json" />
      <Content Remove="appsettings.Production.json" />

      <!-- Other files you want to update in the scope of Debug -->  
      <None Update="other_files">
        <CopyToOutputDirectory>Never</CopyToOutputDirectory>
      </None>
    </ItemGroup>
  </When>
</Choose>

The folder now does not contain appsettings.Development.json and appsettings.Production.json when I run publish using Test environment.

Answer 2

While publishing, we could specify Configuration. To implement your requirement, you could define different configurations by Configuration Manager.

1. Click Debug or Release Dropdown ->Configuration Manager -> New Active solution configuration for Development, Test and etc like DevelopmentPublish and TestPublish

2. Modify project.csproj

   <Project Sdk="Microsoft.NET.Sdk.Web">
   
   <PropertyGroup>
       <TargetFramework>netcoreapp2.1</TargetFramework>
       <Configurations>Debug;Release;DevelopmentPublish</Configurations>
   </PropertyGroup>
   
   <ItemGroup>
       <PackageReference Include="Microsoft.AspNetCore.App" />
       <PackageReference Include="Microsoft.AspNetCore.Razor.Design" Version="2.1.2" PrivateAssets="All" />
   </ItemGroup>
   
   <Target Name="DevelopmentPublish" AfterTargets="AfterPublish" Condition="'$(Configuration)'!='DevelopmentPublish'">
       <Delete Files="$(ProjectDir)$(publishUrl)appsettings.Development.json" />
   </Target>
   <Target Name="TestPublish" AfterTargets="AfterPublish" Condition="'$(Configuration)'!='TestPublish'">
       <Message Text="TestPublish"></Message>
       <Delete Files="$(ProjectDir)$(publishUrl)appsettings.Test.json" />
   </Target>
   </Project>
   

3. While publishing, choose the expected configuration for publish like TestPublish for test publish process.