Hi all, I have a dotnet core 3.1 API c# project which depends on a Postgres database
which works perfectly on a Linux Debian box.
As part of my docker learning curve I thought I would have a shot at getting it to run in a Docker container.
I succeeded using these Dockerfiles and a docker-compose file
# Get Base Image (Full .NET Core SDK) FROM mcr.microsoft.com/dotnet/core/sdk:3.1 AS build-env WORKDIR /app # Copy csproj and restore COPY *.csproj ./ # Copy everything else and build COPY . ./ RUN dotnet publish -c Release -o out # Generate runtime image FROM mcr.microsoft.com/dotnet/core/aspnet:3.1 WORKDIR /app COPY --from=build-env /app/out . ENTRYPOINT ["dotnet", "Mydll.dll"]
FROM postgres ENV POSTGRES_PASSWORD password ENV POSTGRES_DB mydb COPY my_seed_data.sql /docker-entrypoint-initdb.d WORKDIR /
version: '3' services: app: hostname: MyAPI build: . ports: - "1234:9654" volumes: - /home/pjk/Docker/App:/app depends_on: - dbase dbase: hostname: DockMyDatabase build: ./db/ ports: - "5433:5432" volumes: - /home/pjk/Docker/Data:/var/lib/postgresql/data
The entity names are obviously modified but the essence is accurate
All this worked perfectly until I upgraded to netcore 5, the postgres part of the build still worked but my netcore project failed to start with docker logs showing
It was not possible to find any installed .NET Core SDKs Did you mean to run .NET Core SDK commands? Install a .NET Core SDK from:
Oddly when I changed the dotnet build back to 3.1 the api part would fail whereas previously it succeeded
I hope this makes sense to someone
I’ve found the problem it was the final WORKDIR /app in the API Dockerfile so the the container couldn’t find the dotnet command or the dll - I must of accidentiy added it - sorry for the red herring