CC-1541: Update .NET version to 9.0

Author: ryan-gang

compiled_starters/csharp/README.md

@@ -30,7 +30,7 @@ Time to move on to the next stage!
 
 Note: This section is for stages 2 and beyond.
 
-1. Ensure you have `dotnet (8.0)` installed locally
+1. Ensure you have `dotnet (9.0)` installed locally
 1. Run `./your_program.sh` to run your program, which is implemented in
    `src/Server.cs`.
 1. Commit your changes and run `git push origin master` to submit your solution

compiled_starters/csharp/codecrafters-http-server.csproj

@@ -2,7 +2,7 @@
 
   <PropertyGroup>
     <OutputType>Exe</OutputType>
-    <TargetFramework>net8.0</TargetFramework>
+    <TargetFramework>net9.0</TargetFramework>
     <RootNamespace>codecrafters_http_server</RootNamespace>
     <ImplicitUsings>enable</ImplicitUsings>
     <Nullable>enable</Nullable>

compiled_starters/csharp/codecrafters.yml

@@ -7,5 +7,5 @@ debug: false
 # Use this to change the C# version used to run your code
 # on Codecrafters.
 #
-# Available versions: dotnet-8.0
-language_pack: dotnet-8.0
+# Available versions: dotnet-9.0
+language_pack: dotnet-9.0

dockerfiles/dotnet-9.0.Dockerfile

@@ -0,0 +1,17 @@
+# syntax=docker/dockerfile:1.7-labs
+FROM mcr.microsoft.com/dotnet/sdk:9.0-alpine
+
+WORKDIR /app
+
+# Re-build image if any of these files change
+ENV CODECRAFTERS_DEPENDENCY_FILE_PATHS="codecrafters-redis.csproj,codecrafters-redis.sln"
+
+# .git & README.md are unique per-repository. We ignore them on first copy to prevent cache misses
+COPY --exclude=.git --exclude=README.md . /app
+
+# This saves nuget packages to ~/.nuget
+RUN dotnet build --configuration Release .
+
+# Legacy support, remove in the next version of this dockerfile
+RUN echo "cd \${CODECRAFTERS_REPOSITORY_DIR} && dotnet build --configuration Release ." > /codecrafters-precompile.sh
+RUN chmod +x /codecrafters-precompile.sh

solutions/csharp/01-at4/code/README.md

@@ -30,7 +30,7 @@ Time to move on to the next stage!
 
 Note: This section is for stages 2 and beyond.
 
-1. Ensure you have `dotnet (8.0)` installed locally
+1. Ensure you have `dotnet (9.0)` installed locally
 1. Run `./your_program.sh` to run your program, which is implemented in
    `src/Server.cs`.
 1. Commit your changes and run `git push origin master` to submit your solution

solutions/csharp/01-at4/code/codecrafters-http-server.csproj

@@ -2,7 +2,7 @@
 
   <PropertyGroup>
     <OutputType>Exe</OutputType>
-    <TargetFramework>net8.0</TargetFramework>
+    <TargetFramework>net9.0</TargetFramework>
     <RootNamespace>codecrafters_http_server</RootNamespace>
     <ImplicitUsings>enable</ImplicitUsings>
     <Nullable>enable</Nullable>

solutions/csharp/01-at4/code/codecrafters.yml

@@ -7,5 +7,5 @@ debug: false
 # Use this to change the C# version used to run your code
 # on Codecrafters.
 #
-# Available versions: dotnet-8.0
-language_pack: dotnet-8.0
+# Available versions: dotnet-9.0
+language_pack: dotnet-9.0

starter_templates/csharp/code/codecrafters-http-server.csproj

@@ -2,7 +2,7 @@
 
   <PropertyGroup>
     <OutputType>Exe</OutputType>
-    <TargetFramework>net8.0</TargetFramework>
+    <TargetFramework>net9.0</TargetFramework>
     <RootNamespace>codecrafters_http_server</RootNamespace>
     <ImplicitUsings>enable</ImplicitUsings>
     <Nullable>enable</Nullable>

starter_templates/csharp/config.yml

@@ -1,3 +1,3 @@
 attributes:
-  required_executable: dotnet (8.0)
+  required_executable: dotnet (9.0)
   user_editable_file: src/Server.cs