If you need to ignore everything except some directories or files and also ignore some unnecessary files inside those allowed directories you can use the following .dockerignore file:

# Ignore everything
*

# Allow files and directories
!/file.txt
!/src

# Ignore unnecessary files inside allowed directories
# This should go after the allowed directories
**/*~
**/*.log
**/.DS_Store
**/Thumbs.db

Try using wildcards, and both for exclusions and inclusions in this case.

Also, .dockerignore supports ** wildcards for any number of directories depth like go does.

So try this:

src/modules/**
!src/modules/mall/**

Reference

If this doesn't work, could you elaborate in what doesnt work?

Just wanted to add in case others run into this question, that from docker 1.7.0 exclusions are supported in the .dockerignore file. So the example !src/web/public in the question actually works

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

.dockerignore files try to follow Go's filepath.Match rules with the addition of a glob like ** matching any directories in a path. So they aren't exactly the same as glob patterns, or even trying to be. In fact, Docker implemented its own parser so it's not even using filepath.Match any more.

Using dir/.* and dir/*/.* works as expected. But dir/**/.* doesn't seem to work all the time.

This specific issue should be resolved, but I think I've seen the same behaviour in 1.13.1 in certain circumstances.

So with a .dockerignore of dir/**/.* the file dir/file.ext will be excluded but dir/subdir/file.ext will be included.

This is probably worth opening a new issue with Docker if you have a specific reproducible case on 1.13.