asp.net core 2.0 - multiple projects solution docker file

Question

[asp.net core 2.0 and docker for linux]

I am completely new to docker and trying to figure out how to use docker in a case where i have a solution with 2 projects. All tutorials i've seen show with single project.

So, if someone could show step by step solution i would really appreciate it.

i have a solution structure like:

Solution.sln
|______WebAPIProject.csproj
|______ClassLibraryProject.csproj

In Visual studio, i've added docker support to solution and got these files:

Under WebAPIProject, it created this Docker file:

FROM microsoft/aspnetcore:2.0
ARG source
WORKDIR /app
EXPOSE 80
COPY ${source:-obj/Docker/publish} .
ENTRYPOINT ["dotnet", "WebAPIProject.dll"]

then, under separate docker-compose 'project' i've got:

docker-compose.ci.build.yml

version: '3'

services:
  ci-build:
    image: microsoft/aspnetcore-build:1.0-2.0
    volumes:
      - .:/src
    working_dir: /src
    command: /bin/bash -c "dotnet restore ./Solution.sln && dotnet publish ./Solution.sln -c Release -o ./obj/Docker/publish"

and docker.compose.yml file

version: '3'

services:
  WebAPIProject:
    image: WebAPIProject
    build:
      context: ./WebAPIProject
      dockerfile: Dockerfile

I am sure its something trivial with paths but i am just pretty lost with it all so if someone could shed a bit of a light on it?

Answer 1

I finally found a way how to built solutions with docker.

IMPORTANT: For this to work, you have to put the Dockerfile file into the same location where the solution file is

I've just created a docker file with the following content:

FROM microsoft/aspnetcore:2.0 AS base
WORKDIR /app
EXPOSE 80

FROM microsoft/aspnetcore-build:2.0 AS build
WORKDIR /src
COPY Solution.sln ./
COPY ClassLibraryProject/*.csproj ./ClassLibraryProject/
COPY WebAPIProject/*.csproj ./WebAPIProject/

RUN dotnet restore
COPY . .
WORKDIR /src/ClassLibraryProject
RUN dotnet build -c Release -o /app

WORKDIR /src/WebAPIProject
RUN dotnet build -c Release -o /app

FROM build AS publish
RUN dotnet publish -c Release -o /app

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

Note that I think you may have to respect project build dependencies but I don't know really.

Sample call to build:

sudo docker build --no-cache -t webapi:dev .

Sample call to run:

sudo docker run -d=false -p 8080:80 --name webapi webapi:dev

Hope that helps.

Answer 2

While I understand that dotnet core isn't specific to Windows and not everyone is going to be using Visual Studio, there's this neat feature that Microsoft has included inside Visual Studio (Tried it in 2017).

1. Right click on the Web Project.
2. Select Add.
3. Then "Docker Support". This will automatically fetch multiple projects into the container.

If you have multiple Web Projects, repeat the step individually for each.

Here's the reference: https://learn.microsoft.com/en-us/aspnet/core/host-and-deploy/docker/visual-studio-tools-for-docker?view=aspnetcore-2.1#existing-app

If you happen to run with any issues when running the Docker container, try deselecting Hyper-V Services in "Windows Features" (Search for Windows Features in Start Menu), selecting again, and then restarting your computer. Check here.

Answer 3

I had the same problem and all other solutions didn't fit my so I worked out my own. I feel that bellow steps are legible, but if you're new to Docker, I explained it line by line in my blog post dedicated to new Docker users (so you could understand precisely what is going on in this Dockerfile).

1. Keep Dockerfile in project directory (which is, in my point of view, better than keeping it next to solution file, because you can have more than one Docker image per solution).

2. Configure Dockerfile as follows:

FROM mcr.microsoft.com/dotnet/core/sdk:2.2 AS build-env
WORKDIR /app

COPY . ./
RUN dotnet publish PROJECT_NAME -c Release -o out

FROM mcr.microsoft.com/dotnet/core/aspnet:2.2
WORKDIR /app
COPY --from=build-env /app/PROJECT_NAME/out .

ENTRYPOINT ["dotnet", "PROJECT_NAME.dll"]

3. Move .dockerignore file to solution directory - that's required, because Docker CLI takes .dockerignore file only from root directory of the build context (as documentation says), but it's also convenient, because you have one, common set of ignore rules for all projects (similar to .gitignore file), which is easier to maintain.

4. Run build command from solution directory, pointing to Dockerfile in project directory, and setting current directory (.) as build context (to have access to all projects):

docker build -f PROJECT_DIRECTORY/Dockerfile -t IMAGE_NAME .

5. Run container as usual, for example:

docker run -d -p 8080:80 --name my-app-name IMAGE_NAME

Answer 4

This links to an amazing post about how to tackle this issue.

He mentions putting all your code in a src directory. I didn't so that, and this is the file i came up with: (The key is the for file part. I'm sure it's not the best dockerfile otherwise; tips are welcome.)

FROM microsoft/dotnet:2.2-aspnetcore-runtime-stretch-slim AS base
WORKDIR /app
EXPOSE 5000

FROM microsoft/dotnet:2.2-sdk-stretch AS build
WORKDIR /src

COPY ./*.sln ./

COPY */*.csproj ./
RUN for file in $(ls *.csproj); do mkdir -p ${file%.*} && mv $file ${file%.*}; done
RUN dotnet restore

COPY . ./
RUN dotnet build -c Release -o /app

FROM build AS publish
RUN dotnet publish -c Release -o /app

FROM base AS final
WORKDIR /app
COPY --from=publish /app .

ENV ASPNETCORE_URLS="http://*:5000"
ENTRYPOINT ["dotnet", "PersonalSiteApi.dll"]