issue when including image "cannot copy to non-directory"

[kretes]

Hello.

First of all thanks for the tool - this is a good idea to have one like this.

I encountered an issue with the following Dockerfile:

#syntax=bergkvist/includeimage

FROM jupyter/datascience-notebook

INCLUDE openjdk:11.0.7-jre-buster

I get:

> DOCKER_BUILDKIT=1 docker build -t included1 .

failed to solve with frontend dockerfile.v0: failed to solve with frontend gateway.v0: rpc error: code = Unknown desc = failed to build LLB: cannot copy to non-directory: /var/lib/docker/overlay2/wll16e5y1622ez736xegsf987/merged/bin

The same happens when I reverse the images

however when I explicitly build an image with:

FROM jupyter/datascience-notebook

COPY --from=openjdk:11.0.7-jre-buster / /

It works.

Do you have any idea what is going on? Thanks

[bergkvist]

Oh, this is weird! I think you have discovered a problem in Docker Buildkit itself.

Consider the Dockerfile below (without any include syntax):

FROM jupyter/datascience-notebook
COPY --from=openjdk:11.0.7-jre-buster / /

This fails

DOCKER_BUILDKIT=1 docker build -t pyjdk .

Logs:

[+] Building 4.5s (6/6) FINISHED                                                                                                                                            
 => [internal] load build definition from Dockerfile                                                                                                                   0.5s
 => => transferring dockerfile: 119B                                                                                                                                   0.0s
 => [internal] load .dockerignore                                                                                                                                      0.3s
 => => transferring context: 2B                                                                                                                                        0.0s
 => [internal] load metadata for docker.io/jupyter/datascience-notebook:latest                                                                                         1.2s
 => CACHED FROM docker.io/library/openjdk:11.0.7-jre-buster                                                                                                            0.0s
 => => resolve docker.io/library/openjdk:11.0.7-jre-buster                                                                                                             0.5s
 => CACHED [stage-0 1/2] FROM docker.io/jupyter/datascience-notebook@sha256:3dd117acdfe72203d3068a1c40b6a8c3c79e0db473bfecb12d955bc832c01734                           0.0s
 => ERROR [stage-0 2/2] COPY --from=openjdk:11.0.7-jre-buster / /                                                                                                      2.2s
------
 > [stage-0 2/2] COPY --from=openjdk:11.0.7-jre-buster / /:
------
failed to solve with frontend dockerfile.v0: failed to build LLB: cannot copy to non-directory: /var/lib/docker/overlay2/yy5ha7qkd2afgi6a80kv036qr/merged/bin

But this works

docker build -t pyjdk .

Logs:

Sending build context to Docker daemon  3.072kB
Step 1/2 : FROM jupyter/datascience-notebook
latest: Pulling from jupyter/datascience-notebook
a4a2a29f9ba4: Already exists 
127c9761dcba: Already exists 
d13bf203e905: Already exists 
4039240d2e0b: Already exists 
16baf7565818: Already exists 
8d4b4e3fa8e0: Already exists 
9b5cd6dc7e5c: Already exists 
2fadbbcf7ce9: Already exists 
0cd922ae20a5: Already exists 
f5e764406ee1: Already exists 
011a76fea054: Already exists 
1b59e5a8c825: Already exists 
3f4f1174f174: Already exists 
430109c788cf: Already exists 
ef6b34bbbee3: Already exists 
edc996f5b41a: Already exists 
5c69830ff598: Already exists 
17932824baa9: Already exists 
25c98e42fcbd: Already exists 
b6f59bca789a: Already exists 
9bce9285d933: Already exists 
5cf1664cf6c7: Already exists 
b9e19085c433: Already exists 
e14982a374a7: Already exists 
eb44380d0793: Already exists 
72f8a1979c6a: Already exists 
ae57cbe35ef2: Already exists 
Digest: sha256:3dd117acdfe72203d3068a1c40b6a8c3c79e0db473bfecb12d955bc832c01734
Status: Downloaded newer image for jupyter/datascience-notebook:latest
 ---> e86d6091d90f
Step 2/2 : COPY --from=openjdk:11.0.7-jre-buster / /
11.0.7-jre-buster: Pulling from library/openjdk
e9afc4f90ab0: Already exists 
989e6b19a265: Already exists 
af14b6c2f878: Already exists 
68a79816c3e1: Already exists 
e440f69a0a76: Already exists 
837b533a935d: Already exists 
Digest: sha256:562e3027af6520a83990f1831b7e2b6a44e156b18846109f4027cc7caeb8d4a9
Status: Downloaded newer image for openjdk:11.0.7-jre-buster
 ---> 0399e5b96bff
Successfully built 0399e5b96bff
Successfully tagged pyjdk:latest

Assuming you are using the latest version of jupyter/datascience-notebook - it inherits from ubuntu:focal. On the other hand, openjdk inherits from debian:buster.

Since the base images systems don't match - things might go wrong when copying one filesystem on top of another.

[bergkvist]

Some potentially related issues:

• Error: cannot copy to non-directory with buildx only docker/buildx#150
• DOCKER_BUILDKIT=1 docker build fails COPYing a symlink from host moby/buildkit#1197
• DOCKER_BUILDKIT=1 docker build COPY copies symlink incorrectly moby/buildkit#1260

[kretes]

Hi,

I can agree that using different base image can make it a nice mess.

However - you found out that this copying only fails what run with DOCKER_BUILDKIT=1 which (as far as I understand) is a new build system for docker.

Anyway - for my particular case I will anyway try to find at least images with the same base distro.