Dockerize Asp.Net Core Web App With Multiple Layers/Projects (Part1).

Docker + .Net Core + Multilayered Project

Assumptions

1. Docker is working in your machine
2. Your project has a solution (.sln) file

Note: If your project does not have a solution file, read the part 2 of this post (Part 2 is coming soon).

I’ll try to be as direct as possible, lets begin :) .

I created a simple project with multiple layers, github link here .

TheExperiment project solution.

The Experiment project has reference to the Experiment.Procedure and Experiment.Sample only.

The Experiment.UnitTest has reference to the Experiment.Procedure and Experiment. Check the projet in github, here.

Experiment.csproj project references

Note: I created the project with vscode-solution-explorer extension, i didn't use the dotnet new command because i need the .sln file.

vscode-solution-explorer

I created a Dockerfile in the “Experiment” project.

Dockerfile in the Experiment project

FROM mcr.microsoft.com/dotnet/core/sdk:3.0 AS build
WORKDIR /app 
#
# copy csproj and restore as distinct layers
COPY *.sln .
COPY Experiment/*.csproj ./Experiment/
COPY Experiment.Procedure/*.csproj ./Experiment.Procedure/
COPY Experiment.Sample/*.csproj ./Experiment.Sample/
COPY Experiment.UnitTest/*.csproj ./Experiment.UnitTest/ 
#
RUN dotnet restore 
#
# copy everything else and build app
COPY Experiment/. ./Experiment/
COPY Experiment.Procedure/. ./Experiment.Procedure/
COPY Experiment.Sample/. ./Experiment.Sample/ 
#
WORKDIR /app/Experiment
RUN dotnet publish -c Release -o out 
#
FROM mcr.microsoft.com/dotnet/core/aspnet:3.0 AS runtime
WORKDIR /app 
#
COPY --from=build /app/Experiment/out ./
ENTRYPOINT ["dotnet", "Experiment.dll"]

Observe the following

Line 1 -11 builds the project

Line 14 -16 copies the build files . I did not include the Experiment.UnitTest because the Experiment project didn't reference it.

Line 16 -24 Copies the build files where it can run using the runtime.

Line 25 runs the build files with the runtime once the container is started.

To create an image, run the next command in the root of project.

docker build -f Experiment/Dockerfile -t the_experiment .

A docker image is created with a repository name “the_experiment”. To see a list of images, run:

docker image ls

list of docker images

Spin up a container form the image, and bind the pc port 5000 with the container port 80, run:

docker run -d -p 5000:80 — name the_experiment_container the_experiment

Container running…

You can test the app by making a get request to this endpoint using postman or browser.

http://localhost:5000/Experiment/CarryOutExperiment1

or

http://localhost:5000/Experiment/CarryOutExperiment2

Calling an endpoint from the container.

Finally

I hope this helps ;) .