Running docker when dockerfile is in folder inside a project and the solution includes multiple projects

Question

I added a docker support to a dot.net core application, this is what I got

#See https://aka.ms/containerfastmode to understand how Visual Studio uses this Dockerfile to build your images for faster debugging.

FROM mcr.microsoft.com/dotnet/aspnet:5.0-buster-slim AS base
WORKDIR /app
EXPOSE 80
EXPOSE 443

FROM mcr.microsoft.com/dotnet/sdk:5.0-buster-slim AS build
WORKDIR /src
COPY ["SMSys.csproj", ""]
COPY ["../DataLayer/DataLayer.csproj", "../DataLayer/"]
COPY ["../Utilities/Utilities.csproj", "../Utilities/"]
COPY ["../ServiceLayer/ServiceLayer.csproj", "../ServiceLayer/"]
RUN dotnet restore "./SMSys.csproj"
COPY . .
WORKDIR "/src/."
RUN dotnet build "SMSys.csproj" -c Release -o /app/build

FROM build AS publish
RUN dotnet publish "SMSys.csproj" -c Release -o /app/publish

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

My docker file is where 'SMSys.csproj' is.

If I run docker inside that directory, I get:

COPY failed: forbidden path outside the build context:

If I change some of the references of the project after the copy commands and run docker from the outside of the directory where all my projects are, I get multiple over a thousand of errors relating to my solution. The errors relate to missing things (assemblies and packages) as if all the projects are oblivious to one another when in fact they should be well referenced to one another as they do when I launch the project through visual studio.

This is an example of a solution that I followed that didnt work. https://www.jamestharpe.com/docker-include-files-outside-build-context/

Whats the best solution to implement in order to run my project through docker?

UPDATE

    FROM mcr.microsoft.com/dotnet/aspnet:5.0.3-buster-slim AS base
WORKDIR /app
EXPOSE 80
EXPOSE 443

 
FROM mcr.microsoft.com/dotnet/sdk:5.0.103-buster-slim AS build 
WORKDIR /src 

# Prevent 'Warning: apt-key output should not be parsed (stdout is not a terminal)'
ENV APT_KEY_DONT_WARN_ON_DANGEROUS_USAGE=1

# install NodeJS 13.x
# see https://github.com/nodesource/distributions/blob/master/README.md#deb
RUN apt-get update -y
RUN apt-get upgrade -y
RUN apt-get install -y mc
#RUN apt-get install curl gnupg -yq 
#RUN curl -sL https://deb.nodesource.com/setup_12.x | bash -
RUN apt-get install -y npm
 
COPY ["SMSysSolution/SMSys.csproj", "SMSysSolution/"]
COPY ["DataLayer/DataLayer.csproj", "DataLayer/"]
COPY ["Utilities/Utilities.csproj", "Utilities/"]
COPY ["ServiceLayer/ServiceLayer.csproj", "ServiceLayer/"]
COPY ["XUnitIntegrationTests/XUnitIntegrationTests.csproj", "XUnitIntegrationTests/"]
COPY ["XUnitTestProject1/XUnitTestProject1.csproj", "XUnitTestProject1/"]
RUN dotnet restore "./SMSysSolution/SMSys.csproj"
COPY . .
WORKDIR "/src/SMSysSolution"
RUN dotnet build "SMSys.csproj" -c Release -o /app/build

FROM build AS publish
RUN dotnet publish "SMSys.csproj" -c Release -o /app/publish

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

I had to put a few changes to the paths to make it work.

nunohpinheiro · Accepted Answer · 2021-03-02T19:10:53.137

Dockerfile

Please, mind your COPY instructions. The first location is your physical location, whereas the other is the location inside the container. Apparently, you are trying to create a tree like this:

| src
  | SMSys.csproj
| DataLayer
  | ...
| Utilities
  | ...
| ...

I'm not sure if this is exactly what you want...

Moreover, there were some issues with these dotnet Docker images. You may try to use a more recent version.

Please, try to do something like:

FROM mcr.microsoft.com/dotnet/aspnet:5.0.3-buster-slim AS base
WORKDIR /app
EXPOSE 80
EXPOSE 443

FROM mcr.microsoft.com/dotnet/sdk:5.0.103-buster-slim AS build
WORKDIR /src
COPY ["{FOLDER OF THE SMSys.csproj}/SMSys.csproj", "{MATCHING FOLDER OF THE SMSys.csproj}/"]
COPY ["DataLayer/DataLayer.csproj", "DataLayer/"]
COPY ["Utilities/Utilities.csproj", "Utilities/"]
COPY ["ServiceLayer/ServiceLayer.csproj", "ServiceLayer/"]
RUN dotnet restore "./SMSys.csproj"
COPY . .
WORKDIR "/src/{FOLDER OF THE SMSys.csproj}"
RUN dotnet build "SMSys.csproj" -c Release -o /app/build

FROM build AS publish
RUN dotnet publish "SMSys.csproj" -c Release -o /app/publish

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

In this way, you would be creating a tree like:

| src
  | {FOLDER OF THE SMSys.csproj}
    | SMSys.csproj
  | DataLayer
    | ...
  | Utilities
    | ...
  | ...

Running the Dockerfile with context

Taking the example above, to build that image, you must have context for all those folders. Either using docker commands at the same level of the folders for example, or using a docker-compose, you would have to specify that the context is at the top of the folders.

As an example, following the docker-compose approach, you could locate the file like:

| docker-compose.yaml
| {FOLDER OF THE SMSys.csproj}
| DataLayer
| Utilities
| ...

And then, inside the file:

services:
    smsys-app:
        ports:
           - "..." # ports of the services
        build:
            context: .
            dockerfile: {FOLDER OF THE SMSys.csproj}/Dockerfile

This is assuming that you keep the Dockerfile at the same level of the SMSys.csproj, but you may put in another location :)

Running docker when dockerfile is in folder inside a project and the solution includes multiple projects

1 Answers1