.NetCore 微服务 CI 管道 Azure DevOps 构建错误 @ docker image

Question

I am very much new on docker technology, I am getting the build error while creating the .Net Core 3.1 on Azure DevOps CI pipeline on Docker image tasks:

Step 7/17 : COPY ["API2/API2.csproj", "API2/"] COPY failed: CreateFile \\?\\C:\\ProgramData\\docker\\tmp\\docker-builder021493529\\API2\\API2.csproj: The system cannot find the path specified.

My default docker file is

FROM mcr.microsoft.com/dotnet/core/aspnet:3.1-nanoserver-1809 AS base 
WORKDIR /app 
EXPOSE 80
EXPOSE 443
FROM mcr.microsoft.com/dotnet/core/sdk:3.1-nanoserver-1809 AS build
WORKDIR /src
COPY ["API1/API1.csproj", "API1/"]
RUN dotnet restore "API1/API1.csproj"
COPY . .
WORKDIR "/src/API1"
RUN dotnet build "API1.csproj" -c Release -o /app/build
FROM build AS publish
RUN dotnet publish "API1.csproj" -c Release -o /app/publish
FROM base AS final 
WORKDIR /app
COPY --from=publish /app/publish .
ENTRYPOINT ["dotnet", "API1.dll"] 

Please do let me know from where I am doing mistake.

Here are the docker tasks:

Here are the folder and files structure on azure DevOps as well:

Answer 1

COPY ["API1/API1.csproj", "API1/"]

Based on the error message, this should the line that caused the error message.

Step1:

Please ensure you did not configure the .dockerignore file to exclude this file: API1/API1.csproj , which must exists in the directory where you run your build from.

Step2:

After above confirmed, now we can consider the error is caused about the server could not find the csproj file correctly by following the context and the path you provided.

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According to the your original definition: API1/API1.csproj , I guess the actual path of API1.csproj in your repository should be src/API1/API1.csproj , right?

If yes, here has 2 method you can try:

1). Change the COPY definition as:

    COPY ["API1.csproj", "API1/"]

Updated:

When you apply this method, you may succeed to COPY, but failed with Program does not contain a static 'Main' method suitable for an entry point ***** .

Here it means that the COPY . . COPY . . does not copy the files correctly.

At this time, please also change the COPY . . COPY . . to COPY . API1/ COPY . API1/ . This will add folder to dest path .

2). Another way is you could specify API1 to Build context in task:

Below is what I am using, and I do not need make any changes into my dockerfile :

you can input $(Build.Repository.LocalPath) by replacing hard code the context:

Updated:

In Docker 2.*, you can also leave Build context to ** :

You can refer to my previous answer on such question: #1 .

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Based on my opinions, I am not recommend the first method I mentioned above, because it let your dockerfile different with the one which you can run successfully in Visual studio.