C#-API in Docker

[dongsiDaengsi]

Hello dear community.
I have a problem using the LdapForNet package.
I would like to run a C# API (.NET 8) in a Docker container (Linux). The API should access an ActiveDirectory instance.

My Dockerfile looks like this:

FROM mcr.microsoft.com/dotnet/aspnet:8.0 AS base
USER $APP_UID
WORKDIR /app
EXPOSE 8080
EXPOSE 8081

FROM mcr.microsoft.com/dotnet/sdk:8.0 AS build
ARG BUILD_CONFIGURATION=Release
WORKDIR /src
COPY ["API/API.csproj", "API/"]
RUN dotnet restore "API/API.csproj"
COPY . .
WORKDIR "/src/API"
RUN dotnet build "API.csproj" -c $BUILD_CONFIGURATION -o /app/build

FROM build AS publish
ARG BUILD_CONFIGURATION=Release
RUN dotnet publish "API.csproj" -c $BUILD_CONFIGURATION -o /app/publish /p:UseAppHost=false

FROM base AS final
WORKDIR /app
COPY --from=publish /app/publish .
ENTRYPOINT ["dotnet", "API.dll"]

I have also tried to use the following Dockerfile, also without success:

FROM mcr.microsoft.com/dotnet/aspnet:8.0 AS base
USER $APP_UID
WORKDIR /app
EXPOSE 8080
EXPOSE 8081

FROM mcr.microsoft.com/dotnet/sdk:8.0 AS build
ARG BUILD_CONFIGURATION=Release
WORKDIR /src
COPY ["API/API.csproj", "API/"]
RUN dotnet restore "API/API.csproj"
COPY . .
WORKDIR "/src/API"
RUN dotnet build "API.csproj" -c $BUILD_CONFIGURATION -o /app/build

FROM build AS publish
ARG BUILD_CONFIGURATION=Release
RUN dotnet publish "API.csproj" -c $BUILD_CONFIGURATION -o /app/publish /p:UseAppHost=false

FROM base AS final
WORKDIR /app
USER root
RUN apt-get update
RUN apt-get install -y --no-install-recommends libldap2-dev
RUN apt-get install -y --no-install-recommends libldap-common
RUN rm -rf /var/lib/apt/lists/*
RUN ln -s -f /usr/lib/x86_64-linux-gnu/libldap-2.4.so.2 /usr/lib/x86_64-linux-gnu/libldap.so.2
RUN ln -s -f /usr/lib/x86_64-linux-gnu/liblber-2.4.so.2 /usr/lib/x86_64-linux-gnu/liblber.so.2
COPY --from=publish /app/publish .
ENTRYPOINT ["dotnet", "API.dll"]

I read in the documentation that I have to include libldap.so.2 and liblber.so.2. Unfortunately, I have not found a way to make this work.

Would it be possible for one of you to help me with this? And perhaps give me a step-by-step guide?

I have already tried various ways, but I always get the following error message:

"Unable to load shared library 'ldap.so.2' or one of its dependencies. In order to help diagnose loading problems, consider using a tool like strace. If you're using glibc, consider setting the LD_DEBUG environment variable: \n/usr/share/dotnet/shared/Microsoft.NETCore.App/8.0.7/ldap.so.2: cannot open shared object file: No such file or directory\n/app/ldap.so.2: cannot open shared object file: No such file or directory\n/usr/share/dotnet/shared/Microsoft.NETCore.App/8.0.7/libldap.so.2: cannot open shared object file: No such file or directory\n/app/libldap.so.2: cannot open shared object file: No such file or directory\n/usr/share/dotnet/shared/Microsoft.NETCore.App/8.0.7/ldap.so.2.so: cannot open shared object file: No such file or directory\n/app/ldap.so.2.so: cannot open shared object file: No such file or directory\n/usr/share/dotnet/shared/Microsoft.NETCore.App/8.0.7/libldap.so.2.so: cannot open shared object file: No such file or directory\n/app/libldap.so.2.so: cannot open shared object file: No such file or directory\n"

Many thanks in advance.