How to integrate 'npm install' into ASP.NET CORE 2.1 Docker build

Question

I have not found a way to build a ASP.NET Core 2.1 Docker image while doing a proper npm install during the build process.

My Dockerfile looks like this (one that has been generated from Visual Studio):

FROM microsoft/dotnet:2.1-aspnetcore-runtime AS base
WORKDIR /app
EXPOSE 80

FROM microsoft/dotnet:2.1-sdk AS build
WORKDIR /src
COPY --from=frontend . .
COPY ["myProject.WebUi/myProject.WebUi.csproj", "myProject.WebUi/"]
COPY ["myProject.SearchIndex/myProject.SearchIndex.csproj", "myProject.SearchIndex/"]
COPY ["myProject.SearchIndex.Common/myProject.SearchIndex.Common.csproj", "myProject.SearchIndex.Common/"]

RUN dotnet restore "myProject.WebUi/myProject.WebUi.csproj"
COPY . .
WORKDIR "/src/myProject.WebUi"
RUN dotnet build "myProject.WebUi.csproj" -c Release -o /app

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

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

In the previous images from Microsoft (e.g. aspnetcore-build:2.0) were third-party tools provided, such as npm, yarn, bower, pip, ...)

At the moment I do a local npm install in the project folder. But for automatic building like it is offered from Docker Hub or Azure Container Registry the note modules are missing.

Answer 1

Found the solution:

FROM microsoft/dotnet:2.1-aspnetcore-runtime AS base
WORKDIR /app
EXPOSE 80

FROM microsoft/dotnet:2.1-sdk AS build
WORKDIR /src
COPY --from=frontend . .
COPY ["myProject.WebUi/myProject.WebUi.csproj", "myProject.WebUi/"]
COPY ["myProject.SearchIndex/myProject.SearchIndex.csproj", "myProject.SearchIndex/"]
COPY ["myProject.SearchIndex.Common/myProject.SearchIndex.Common.csproj", "myProject.SearchIndex.Common/"]

RUN dotnet restore "myProject.WebUi/myProject.WebUi.csproj"
COPY . .
WORKDIR "/src/myProject.WebUi"
RUN apt-get update -yq && apt-get upgrade -yq && apt-get install -yq curl git nano
RUN curl -sL https://deb.nodesource.com/setup_8.x | bash - && apt-get install -yq nodejs build-essential
RUN npm install -g npm
RUN npm install
RUN dotnet build "myProject.WebUi.csproj" -c Release -o /app

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

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

Answer 2

Update for ASP.NET Core 3.0 Web App with SPA

FROM mcr.microsoft.com/dotnet/core/sdk:3.0 AS build
WORKDIR /app

# 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 -yq 
RUN apt-get install curl gnupg -yq 
RUN curl -sL https://deb.nodesource.com/setup_13.x | bash -
RUN apt-get install -y nodejs

# copy csproj and restore as distinct layers
COPY *.sln .
COPY MyApplication/*.csproj ./MyApplication/
RUN dotnet restore

# copy everything else and build app
COPY MyApplication/. ./MyApplication/
WORKDIR /app/MyApplication
RUN dotnet publish -c Release -o out

FROM mcr.microsoft.com/dotnet/core/aspnet:3.0 AS runtime
WORKDIR /app
COPY --from=build /app/MyApplication/out ./
ENTRYPOINT ["dotnet", "MyApplication.dll"]

Then

docker build --pull -t MyApplication
docker run --name myapp --rm -it -p 8000:80 MyApplication

The app will be available at localhost:8000.

Answer 3

In my case, I needed to have a docker image running a nodeJS project which is able to execute script like "dotnet xxx.xxx.dll".

I was struggling trying to fix "dotnet command not found" inside my docker.

I succeeded to fix it easily by adding at the beginning of my Dockerfile:

FROM node:alpine AS node_base
FROM mcr.microsoft.com/dotnet/core/sdk:3.1 AS build-env
COPY --from=node_base . .

RUN echo "NODE Version:" && node --version
RUN echo "NPM Version:" && npm --version
RUN echo "dotnet Version:" &&  dotnet --version

(you can adjust versions accordingly)

I took inspiration from this github issue.

Hope this trick can help you too :)