COPY with docker but with exclusion

问题:

In a Dockerfile, I have

COPY . .

I want to exclude an entire directory, in my case, node_modules directory.

Something like this:

   COPY [all but **/node_modules/**] .

Is this possible with Docker?

回答1:

Create file .dockerignore in your docker build context directory (so in this case, most likely a directory that is a parent to node_modules) with one line in it:

**/node_modules

although you probably just want:

node_modules

Info about dockerignore: https://docs.docker.com/engine/reference/builder/#dockerignore-file

回答2:

For those who can't use a .dockerignore file (e.g. if you need the file in one COPY but not another):

Yes, but you need multiple COPY instructions. Specifically, you need a COPY for each letter in the filename you wish to exclude.

COPY [^n]*    # All files that don't start with 'n'
COPY n[^o]*   # All files that start with 'n', but not 'no'
COPY no[^d]*  # All files that start with 'no', but not 'nod'

Continuing until you have the full file name, or just the prefix you're reasonably sure won't have any other files.

回答3:

Adding .dockerignore works for me. One additional point Those who are trying this solution on Windows , windows will not let you create .dockerignore file (as it doesn't by default allows creating file starting with .)

the trick to that is mentioned here : https://www.hanselman.com/blog/HowToCreateAFileWithADotPrefixInWindowsExplorer.aspx

which is include an ending dot also, like : .dockerignore. and hit enter ( provided you have enabled view extension options from folder options )