Dockerfile COPY 只复制它应该复制的目录的一个子目录

Question

I have directory structure like this:

opt
  - dcmtk-3.6.5-linux-x86_64-static
    | - bin    
    | - etc
    | - share
     

In each of there subdirectories there are also some files.

In Dockerfile I have line

COPY opt/* /opt/

But when I create container from this image, and run /bin/bash , and go to /opt and run ls -al I can see there is only bin directory, with it's content. No dcmtk-3.6.5-linux-x86_64-static directory, no other subdirectories like etc or share .

There are also some other files I keep in opt , those are copied just as expected.

Why isn't whole dcmtk-3.6.5-linux-x86_64-static copied?

Answer 1

As the documentation says:

If <src> is a directory, the entire contents of the directory are copied, including filesystem metadata.

So you should use the following:

COPY opt /opt

Just leave out the /* and specify only the directory.

Edit 01.10.2020 :

Just tried again with the following setup:

ls -lR
total 8
-rw-r--r--  1 peter  staff   34  1 Okt 13:06 Dockerfile
drwxr-xr-x  4 peter  staff  128  1 Okt 13:01 opt

./opt:
total 0
drwxr-xr-x  2 peter  staff   64  1 Okt 13:01 emptydir
drwxr-xr-x  4 peter  staff  128  1 Okt 13:01 foo

./opt/emptydir:

./opt/foo:
total 0
drwxr-xr-x  3 peter  staff  96  1 Okt 13:01 bar
-rw-r--r--  1 peter  staff   0  1 Okt 13:01 foo.txt

./opt/foo/bar:
total 0
-rw-r--r--  1 peter  staff  0 29 Sep 19:15 bar.txt

Dockerfile:

FROM busybox:latest
COPY opt /opt

building the image:

docker build -t so-test .
Sending build context to Docker daemon   5.12kB
Step 1/2 : FROM busybox:latest
 ---> 6858809bf669
Step 2/2 : COPY opt /opt
 ---> Using cache
 ---> f6f2692b571a
Successfully built f6f2692b571a
Successfully tagged so-test:latest

running the container:

docker run -it so-test /bin/sh
/ #

and checking what's in there:

# ls -lR /opt
/opt:
total 8
drwxr-xr-x    2 root     root          4096 Oct  1 11:01 emptydir
drwxr-xr-x    3 root     root          4096 Oct  1 11:01 foo

/opt/emptydir:
total 0

/opt/foo:
total 4
drwxr-xr-x    2 root     root          4096 Oct  1 11:01 bar
-rw-r--r--    1 root     root             0 Oct  1 11:01 foo.txt

/opt/foo/bar:
total 0
-rw-r--r--    1 root     root             0 Sep 29 17:15 bar.txt

So the whole directory structure was copied, including the empty directory. There must be something interfering in you setup

Answer 2

Extracts from the documentation (in relevant order for my answer)

If multiple <src> resources are specified, either directly or due to the use of a wildcard , then <dest> must be a directory, and it must end with a slash /

[...]

If <src> is a directory, the entire contents of the directory are copied, including filesystem metadata.

Note: The directory itself is not copied, just its contents.

Solution:

COPY opt /opt/