Symlinks broken behavior

iSeiryu commented 3 years ago

[x] I have tried with the latest version of my channel (Stable or Edge)
[ ] I have uploaded Diagnostics - there is no diagnostic to report.

Expected behavior

The build can see the target file that symlink points to

Actual behavior

It works as expected inside WSL but not on Windows itself. I (and other devs) get "No such file or directory" when running on Win 10.

Information

Windows Version: Windows 10 Pro 10.0.19041 Build 19041
Docker Desktop Version: 2.3.0.5 (48029)
Docker Engine Version: 19.03.12, build 48a66213fe
Are you running inside a virtualized Windows e.g. on a cloud server or on a mac VM: No

Steps to reproduce the behavior

Just need anything with a symlink to a file in it. My test folder structure

symlink-test
+-- common
|   +-- target-file.txt  --  contains "Hello from the target-file!"
+-- Dockerfile
+-- link.txt -> common/target-file.txt

to create a soft link use mklink on Win or ln on Linux

ln -s common/target-file.txt link.txt

My test Dockerfile (I used all sorts of images, not just vault):
```
FROM vault
WORKDIR /src
COPY . .
RUN ls -al && cat link.txt
```

When I run it inside WSL2 (my Docker Desktop runs on it too) it works just fine

/mnt/c/work/repos/test/symlink-test$ docker build . -t symlink-test:latest
Sending build context to Docker daemon  4.096kB
Step 1/4 : FROM vault
---> aac433bb6835
Step 2/4 : WORKDIR /src
---> Using cache
---> 3b1f2703087a
Step 3/4 : COPY . .
---> c858c20b96aa
Step 4/4 : RUN ls -al && cat link.txt
---> Running in f9a8325ca6b0
total 16
drwxr-xr-x    1 root     root          4096 Sep 24 20:44 .
drwxr-xr-x    1 root     root          4096 Sep 24 20:44 ..
-rwxrwxrwx    1 root     root            62 Sep 24 20:39 Dockerfile
drwxrwxrwx    2 root     root          4096 Sep 24 20:33 common
lrwxrwxrwx    1 root     root            22 Sep 24 20:37 link.txt -> common/target-file.txt
Hello from the target-file!
Removing intermediate container f9a8325ca6b0
---> d85501725e83
Successfully built d85501725e83
Successfully tagged symlink-test:latest

But when I run it on Win 10 it gives me this:

docker build . -t symlink-test:latest
Sending build context to Docker daemon  4.096kB
Step 1/4 : FROM vault
 ---> aac433bb6835
Step 2/4 : WORKDIR /src
 ---> Using cache
 ---> 3b1f2703087a
Step 3/4 : COPY . .
 ---> Using cache
 ---> 9b909a2f9af8
Step 4/4 : RUN ls -al && cat link.txt
 ---> Running in 37cb902aa2a4
total 16
drwxr-xr-x    1 root     root          4096 Sep 24 20:43 .
drwxr-xr-x    1 root     root          4096 Sep 24 21:10 ..
-rwxr-xr-x    1 root     root            62 Sep 24 20:39 Dockerfile
drwxr-xr-x    2 root     root          4096 Sep 24 20:33 common
lrwxrwxrwx    1 root     root            22 Sep 24 20:37 link.txt -> common\target-file.txt
cat: can't open 'link.txt': No such file or directory
The command '/bin/sh -c ls -al && cat link.txt' returned a non-zero code: 1

iSeiryu commented 3 years ago

I've read through the SO questions like these 2 https://stackoverflow.com/questions/31881904/docker-follow-symlink-outside-context https://stackoverflow.com/questions/42569303/docker-does-not-follow-symlinks-within-build-directory

If this is not supported at all why is it working inside our CICD and inside our WSL 2? We can reproduce it on different machines.

docker-robott commented 3 years ago

Issues go stale after 90 days of inactivity. Mark the issue as fresh with /remove-lifecycle stale comment. Stale issues will be closed after an additional 30 days of inactivity.

Prevent issues from auto-closing with an /lifecycle frozen comment.

If this issue is safe to close now please do so.

Send feedback to Docker Community Slack channels #docker-for-mac or #docker-for-windows. /lifecycle stale

iSeiryu commented 3 years ago

/remove-lifecycle stale

docker-robott commented 3 years ago

Issues go stale after 90 days of inactivity. Mark the issue as fresh with /remove-lifecycle stale comment. Stale issues will be closed after an additional 30 days of inactivity.

Prevent issues from auto-closing with an /lifecycle frozen comment.

If this issue is safe to close now please do so.

Send feedback to Docker Community Slack channels #docker-for-mac or #docker-for-windows. /lifecycle stale

iSeiryu commented 3 years ago

/lifecycle frozen

docker / for-win