Docker - failed to compute cache key: not found - runs fine in Visual Studio

Question

I've generated a Dockerfile with Visual Studio. It runs in Visual Studio just fine and now I'm trying to build it from Windows itself (docker build ., and I tried many combinations). Yet I get the following error:

> [build 3/7] COPY [client/client.csproj, client/]:
------
failed to compute cache key: "/client/client.csproj" not found: not found

When I change copy to ./client.csproj it does continue and then I get:

 => ERROR [build 7/7] RUN dotnet build "client.csproj" -c Release -o /app/build                3.3s
------
> [build 7/7] RUN dotnet build "client.csproj" -c Release -o /app/build:
#15 0.652 Microsoft (R) Build Engine version 16.8.3+39993d9d for .NET
#15 0.652 Copyright (C) Microsoft Corporation. All rights reserved.
#15 0.652
#15 1.169   Determining projects to restore...
#15 1.483   All projects are up-to-date for restore.
#15 3.231 CSC : error CS5001: Program does not contain a static 'Main' method suitable for an entry point [/src/client/client.csproj]
#15 3.240
#15 3.240 Build FAILED.
#15 3.240
#15 3.240 CSC : error CS5001: Program does not contain a static 'Main' method suitable for an entry point [/src/client/client.csproj]
#15 3.240     0 Warning (5)
#15 3.240     1 Error (5)
#15 3.240
#15 3.240 Time Elapsed 00:00:02.51
-----
executor failed running [/bin/sh -c dotnet build "client.csproj" -c Release -o /app/build]: exit code: 1

What am I doing wrong? I changed Docker Linux to Windows, changed WSL, and restarted everything.

#See https://aka.ms/containerfastmode to understand how Visua...

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 ["client/client.csproj", "client/"]
RUN dotnet restore "client/client.csproj"
COPY . .
WORKDIR "/src/client"
RUN dotnet build "client.csproj" -c Release -o /app/build

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

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

It's work for me https://stackoverflow.com/a/63257667/15203500 You have to move your docker file One directory up — m.mitin, Feb 13 '21 at 13:44

score 372 · Answer 1 · edited Jan 04 '23 at 17:14

Check your .dockerignore file. Possible it ignores needed files for copy command and you get failed to compute cache key error.

.dockerignore may be configured to minimize the files sent to docker for performance and security:

* 
!dist/

The first line * disallows all files. The second line !dist/ allows the dist folder

This can cause unexpected behavior:

FROM nginx:latest

# Fails because of * in .dockerignore
# failed to compute cache key: "/nginx.conf.spa" not found: not found
# Fix by adding `!nginx.conf.spa`  to .dockerignore
COPY nginx.conf.spa /etc/nginx/nginx.conf

RUN mkdir /app

# Works because of !dist/ in .dockerignore
COPY dist/spa /app

Belts and suspenders.

score 198 · Accepted Answer · edited Apr 18 '23 at 09:06

The way Visual Studio does it is a little bit odd.

Instead of launching docker build in the folder with the Dockerfile, it launches in the parent folder and specifies the Dockerfile with the -f option.

I was using the demo project (trying to create a minimal solution for another question) and struck the same situation.

Setup for my demo project is

\WorkerService2  ("solution" folder)
   +- WorkerService2.sln
   +- WorkserService2  ("project" folder)
       +- DockerFile
       +- WorkerService2.csproj
       +- ... other program files

So I would expect to go

cd \Workerservice2\WorkerService2
docker build .

But I get your error message.

 => ERROR [build 3/7] COPY [WorkerService2/WorkerService2.csproj, WorkerService2/]                                                                                                                        0.0s
------
 > [build 3/7] COPY [WorkerService2/WorkerService2.csproj, WorkerService2/]:
------
failed to compute cache key: "/WorkerService2/WorkerService2.csproj" not found: not found

Instead, go to the parent directory, with the .sln file and use the docker -f option to specify the Dockerfile to use in the subfolder:

cd \Workerservice2
docker build -f WorkerService2\Dockerfile --force-rm -t worker2/try7 .

docker run -it worker2/try7

Note the final dot on the docker build command.

For docker the final part of the command is the location of the files that Docker will work with. Usually this is the folder with the Dockerfile in, but that's what's different about how VS does it. In this case the dockerfile is specified with the -f. Any paths (such as with the COPY instruction in the dockerfile) are relative to the location specified. The . means "current directory", which in my example is \WorkerService2.

I got to this stage by inspecting the output of the build process, with verbosity set to Detailed. If you choose Tools / Options / Projects and Solutions / Build and Run you can adjust the build output verbosity, I made mine Detailed.

I think I've worked out why Visual Studio does it this way. It allows the project references in the same solution to be copied in.

If it was set up to do docker build from the project folder, docker would not be able to COPY any of the other projects in the solution in. But the way this is set up, with current directory being the solution folder, you can copy referenced projects (subfolders) into your docker build process.

Gah. It was that last dot that was getting me. I tried all sorts of combinations of the full file or a path without the file, but I either got the `file not found` issue, or the dreaded `docker build requires exactly 1 argument` message. Not gonna lie, learning the tiniest new thing in docker is like pulling teeth, FFS. It works great once you figure out the obscure syntax and methods, but until then it's one headdesk after another. — Mike Loux, Jul 23 '21 at 15:11
Yeah, what's the dot at the end for? You're specifying two docker files. — tblev, Jul 26 '21 at 19:33
@tblev The '.' at the end is telling docker which directory to run from, in this case, the root of the solution rather than the project. Careful though, the COPY command is case sensitive and if you have your project directory named inconsistently with the command (camel case etc.) that will confuse docker — Goku, Nov 02 '21 at 17:37
I think this answer helps a lot. I had a similar problem when working with devcontainers in vscode. When inspecting the `docker buildx build` command when opening a folder in a container I saw that the command does not end with a `.` but with `/path/to/repo/workingdir`. The `Dockerfile` resided in `workingdir/subdir/.devcontainter`. So instead of `COPY file.txt .` I had to use `COPY subdir/file.txt`. — Ken Jiiii, Sep 30 '22 at 06:18
I love the inclusion of the debugging process in a small note after the answer itself! Noting how to get detailed verbosity with the IDE at hand is very useful to independent visitors. — Simon, Apr 13 '23 at 08:05

Ismail Umar · Answer 3 · 2021-11-04T21:39:42.957

25

I had the same issue, I set the Docker environment to Windows in when adding Docker support. Even running in Visual Studio threw error to that. I changed the environment to Linux as my Docker is running in the Windows Subsystem for Linux (WSL).

Then I moved back to the terminal to run the commands.

I was able to resolve this by moving to the Solutions folder (Root folder).

And I did docker build like this:

docker build -t containername/tag -f ProjectFolder/Dockerfile .

Then I did docker run:

docker run containername/tag

edited Nov 04 '21 at 21:39

answered Jun 22 '21 at 20:21

Ismail Umar

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3

Using -f option in the .sln-folder had already been an answer 10 days before this answer. – questionto42 Jul 15 '21 at 16:51
1

Re *"Linux Subsystem for Windows"*: Do you mean *[Windows Subsystem for Linux](https://en.wikipedia.org/wiki/Windows_Subsystem_for_Linux)* (WSL)? – Peter Mortensen Oct 15 '21 at 17:37

score 17 · Answer 4 · answered Mar 11 '21 at 23:35

17

Asking for a directory that does not exist throws this error.

In my case, I tried

 > [stage-1  7/14] COPY /.ssh/id_rsa.pub /.ssh/:
------
failed to compute cache key: "/.ssh/id_rsa.pub" not found: not found

I had forgotten to add the /.ssh folder to the project directory. In your case you should check whether /client is really a subfolder of your Dockerfile build context.

answered Mar 11 '21 at 23:35

questionto42

7,175
4
57
90

1

same here, made a typo – ngood97 May 27 '22 at 21:36
2

Or maybe you renamed/moved a file that used to be referenced in your Docker file (ADD/COPY/etc.) and now is missing for the docker build to run. Whatever makes it be missing. – user18099 Feb 18 '23 at 19:15
1

Same in my case. Glad I searched this. I simply didn't think to check for a typo, lol – Patrick Michaelsen Feb 24 '23 at 01:18

score 15 · Answer 5 · answered Jan 30 '22 at 01:35

15

The following command was failing with failed to compute cache key: not found:

docker build -t tag-name:v1.5.1 - <Dockerfile

Upon changing the command to the following it got fixed:

docker build -t tag-name:v1.5.1 -f Dockerfile .

answered Jan 30 '22 at 01:35

Vishrant

15,456
11
71
120

Simply doing `docker build .` worked for me since "_Dockerfile_" is the default dockerfile filename. – Qwerty Oct 11 '22 at 23:28

score 6 · Answer 6 · answered Feb 19 '22 at 08:23

6

Error : failed to compute cache key: "src" not found: not found

in my case , folder/file excluded in .dockerignore

after resolving file from dockerignore able to create image.

answered Feb 19 '22 at 08:23

Prabhu

76
2
6

score 5 · Answer 7 · answered May 18 '21 at 13:22

5

In my case I found that docker build is case sensitive in directory name, so I was writing /bin/release/net5.0/publish in the COPY instruction and failed with the same error, I've just changed to /bin/Release/net5.0/publish and it worked

answered May 18 '21 at 13:22

Luis Diego Rojas

182
1
11

1

This was the answer for me. Windows not being case sensitive on pathing makes working with docker fun sometimes. – RubberChickenLeader Jul 14 '21 at 15:14

score 4 · Answer 8 · answered Apr 19 '22 at 04:02

4

In my case, I had something like this:

  FROM mcr.microsoft.com/dotnet/aspnet:5.0
  COPY bin/Release/net5.0/publish/ app/
  WORKDIR /app
  ENTRYPOINT ["dotnet", "MyApi.dll"]

And I finally realized that I had the bin folder in my .dockerignore file.

answered Apr 19 '22 at 04:02

contactmatt

18,116
40
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score 3 · Answer 9 · answered Nov 10 '22 at 16:12

3

I had a similar issues: Apparently, docker roots the file system during build to the specified build directory for security reasons. As a result, COPY and ADD cannot refer to arbitrary locations on the host file system. Additionally, there are other issues with syntax peculiarities. What eventually worked was the following:

COPY ./script_file.sh  /
RUN /script_file.sh

answered Nov 10 '22 at 16:12

George

2,451
27
37

Other solutions here were overkill. This was simplest and cleanest. However, you may need to run `docker builder prune` if you still get cache errors. – lacostenycoder Mar 15 '23 at 14:53

score 1 · Answer 10 · answered Aug 14 '21 at 21:15

I had the same issue. In my case there was a wrong directory specified. My Dockerfile was:

FROM mcr.microsoft.com/dotnet/sdk:5.0 AS publish
WORKDIR /app
COPY . .
RUN dotnet publish -c Release -o publish/web src/MyApp/MyApp.csproj

FROM mcr.microsoft.com/dotnet/aspnet:5.0
WORKDIR /app
COPY --from=publish publish/web .
EXPOSE 80
CMD ASPNETCORE_URLS=http://*:$PORT dotnet MyApp.dll

Then I realised that in the second build stage I am trying to copy project files from directory publish/web:

COPY --from=publish publish/web .

But as I specified workdir /app in the first stage, my files are located in that directory in image filesystem, so changing path from publish/web to app/publish/web resolved my issue.

So my final working Dockerfile is:

FROM mcr.microsoft.com/dotnet/sdk:5.0 AS publish
WORKDIR /app
COPY . .
RUN dotnet publish -c Release -o publish/web src/MyApp/MyApp.csproj

FROM mcr.microsoft.com/dotnet/aspnet:5.0
WORKDIR /app
COPY --from=publish app/publish/web .
EXPOSE 80
CMD ASPNETCORE_URLS=http://*:$PORT dotnet MyApp.dll

score 1 · Answer 11 · answered Jan 04 '22 at 18:25

1

In my case there was a sneaky trailing whitespace in the file name.

------
 > [3/3] COPY init.sh ./:
------
failed to compute cache key: "/init.sh" not found: not found

So the file was actually called "init.sh " instead of "init.sh".

answered Jan 04 '22 at 18:25

Niklas Gruhn

183
7

score 1 · Answer 12 · answered May 16 '23 at 22:28

1

The nginx.conf file must be included to be published. Right Click on the nginx.conf file and open the Properties. Change "Copy to output directory" to "Copy always"

answered May 16 '23 at 22:28

Sven

11
1

score 0 · Answer 13 · edited Oct 15 '21 at 17:30

I had faced the same issue.

The reason was the name of the DLL file in the Docker file is case sensitive.

FROM mcr.microsoft.com/dotnet/sdk:5.0 AS build
WORKDIR /src
COPY MyFirstMicroService.csproj .
RUN dotnet restore
COPY . .
RUN dotnet publish -c release -o /app

FROM mcr.microsoft.com/dotnet/aspnet:5.0
WORKDIR /app
COPY --from=build /app .
ENTRYPOINT ["dotnet", "**MyFirstMicroService.dll**"]

This .dll name should match your .csproj file.

score 0 · Answer 14 · answered Jan 22 '22 at 14:49

This also happens when you don't provide the proper path to your COPY command input. The most important clue I had is that WORKDIR command opens a folder for the container, not in the windows explorer (so it doesn't affect the path you need to specify for the COPY command).

score 0 · Answer 15 · answered Feb 08 '22 at 16:54

In my Case, i was doing mistake in '/' and ''. Let me explain Open your dockerfile (it should be named as dockerfile only, not DockerFile or Dockerfile). You may have something like this- FROM mcr.microsoft.com/dotnet/runtime:5.0 COPY bin\Release\net5.0\publish . ENTRYPOINT ["dotnet", "HelloDocker.dll"]

Replace COPY bin\Release\net5.0\publish . to COPY bin/Release/net5.0/publish .

score 0 · Answer 16 · answered May 04 '22 at 17:48

in my case, it was a wrong Build with PATH configuration e.g. Docker build context

Simple docker script
```
docker build . 
```
where . is path to build context

Gradle+Docker

docker {
    dependsOn build
    dependsOn dockerFilesCopy
    name "${project.name}:${project.version}"
    files "build" // path to build context
}

Gradle+GitHub action

name: Docker build and push

on:
  push:
    branches: [ main ]

# ...

jobs:
  build:
    runs-on: ubuntu-latest

    # ...

    steps:
      - name: Checkout
        uses: actions/checkout@v2

     # ...

      - name: Build and export to Docker
        uses: docker/build-push-action@v2
        with:
          # ...
          file: src/main/docker/Dockerfile      
          context: ./build                      # path to build context

score 0 · Answer 17 · answered May 23 '22 at 02:52

In my case, with Angular project, my project was in the folder called ex: My-Folder-Project and I was putting on Dockerfile COPY --from=publish app/dist/My-Folder-Project . But of course the correct thing is put the "name" in your package.json like COPY --from=publish app/dist/name-in-package.json .

score 0 · Answer 18 · answered Sep 10 '22 at 00:40

In my case I changed context, and path of Dockerfile within docker-compose.yml config:

services:
    server:
        # inheritance structru
        extends:
            file: ../../docker-compose.server.yml
        # I recommend you to play with this paths
        build:
            context: ../../
            dockerfile: ./apps/${APP_NAME}/Dockerfile
        ...

score 0 · Answer 19 · answered Apr 17 '23 at 21:28

I run into a similar issue where I was attempting to run the docker build command. I created a folder called "Docker" and inside of it another folder called "getting-started". I kept running into the error:

"failed to compute cache key: "/public" not found: not found"

Took me a while to realize that I should run the command from the "getting-started" folder instead of "Docker". It worked on I did so..

score 0 · Answer 20 · edited Apr 25 '23 at 00:51

0

For Laravel users...

I got this error when running docker compose up and it was due to there being a storage folder symlink in my public folder.

After deleting the symlink, the command executed successfully.

edited Apr 25 '23 at 00:51

Marc

4,820
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answered Apr 19 '23 at 08:51

frijj2k

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score 0 · Answer 21 · answered Aug 16 '23 at 10:18

0

I also got this error, first it resolved by removing some files from .dockerignore.

After that, I used a variable and haven't used $ operator to resolve it. Added $ before "{variable}", it worked for me.

answered Aug 16 '23 at 10:18

dontwanttoshare

1
1

Docker - failed to compute cache key: not found - runs fine in Visual Studio

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