CI/CD for .NET Core

If you have a .NET API that you want to containerize, here are the steps to prepare it.

1. Create docker image
2. Push to repository
3. Setup ECS

The TLS 1.0 option is needed if your SQL Server database does not support TLS 1.2. The recommended option is to update your database to the secure protocol.

You may also change sdk and aspnet version to 5.0 if you haven't updated to 6.0 yet.

This Dockerfile uses a multi-stage build to get an optimal image size.

Dockerfile

FROM mcr.microsoft.com/dotnet/sdk:6.0 AS build-env

WORKDIR /app

# Copy csproj and restore as distinct layers

COPY *.csproj ./

RUN dotnet restore

# Copy everything else and build

COPY . ./

RUN dotnet publish -c Release -o out

# Build runtime image

FROM mcr.microsoft.com/dotnet/aspnet:6.0

WORKDIR /app

# Enable TLS 1.0

RUN sed -i 's/DEFAULT@SECLEVEL=2/DEFAULT@SECLEVEL=1/g' /etc/ssl/openssl.cnf

RUN sed -i 's/MinProtocol = TLSv1.2/MinProtocol = TLSv1/g' /etc/ssl/openssl.cnf

RUN sed -i 's/DEFAULT@SECLEVEL=2/DEFAULT@SECLEVEL=1/g' /usr/lib/ssl/openssl.cnf

RUN sed -i 's/MinProtocol = TLSv1.2/MinProtocol = TLSv1/g' /usr/lib/ssl/openssl.cnf

COPY --from=build-env /app/out .

ENTRYPOINT ["dotnet", "myapp-whatever.dll"]

buildspec.yml

version: 0.2

phases:

  pre_build:

    commands:

      - echo Logging in to Amazon ECR...

      - aws --version

      - aws ecr get-login-password --region $AWS_DEFAULT_REGION | docker login --username AWS --password-stdin $AWS_ACCOUNT_ID.dkr.ecr.$AWS_DEFAULT_REGION.amazonaws.com

      - REPOSITORY_URI=$AWS_ACCOUNT_ID.dkr.ecr.$AWS_DEFAULT_REGION.amazonaws.com/$IMAGE_REPO_NAME

      - COMMIT_HASH=$(echo $CODEBUILD_RESOLVED_SOURCE_VERSION | cut -c 1-7)

      - IMAGE_TAG=${COMMIT_HASH:=latest}

  build:

    commands:

      - echo Build started on `date`

      - echo Building the Docker image...

      - docker build -t $REPOSITORY_URI:latest .

      - docker tag $REPOSITORY_URI:latest $REPOSITORY_URI:$IMAGE_TAG

  post_build:

    commands:

      - echo Build completed on `date`

      - echo Pushing the Docker images...

      - docker push $REPOSITORY_URI:latest

      - docker push $REPOSITORY_URI:$IMAGE_TAG

      - echo Writing image definitions file...

      - printf '[{"name":"%s","imageUri":"%s"}]' $IMAGE_REPO_NAME $REPOSITORY_URI:$IMAGE_TAG > imagedefinitions.json

artifacts:

    files: imagedefinitions.json

If you don't have a health check endpoint, this is important for containers for the orchestrator to know if your container is ready or if needs to be restarted.

Startup.cs

app.UseEndpoints(endpoints =>

            {

                endpoints.MapControllers();

                endpoints.MapHealthChecks("/api/health");

            });