Better/Nicest way to symlink into multiple folders?-CodePudding

I have this directory structure, and I need to generate symlinks for common/provider.tf in both environments/prod and environments/prod/module.

/
├─ common
│  ├─ provider.tf
├─ environments/
│  ├─ prod/
│  │  ├─ module/

I managed to do it this way:

  if [ -e "../../../common/provider.tf" ]; then  # I'm in environments/prod/module
    ln -s ../../../common/provider.tf provider.tf
  else  # I'm in the root folder "/"
    ln -s common/provider.tf $environment/provider.tf  # $environment is /environments/prod
  fi

But I realize that my code sucks and I can't come up with a better idea.

Any idea on how to do it better? Note: There are lots of environments and lots of modules, I'm using that code recursively.

CodePudding user response：

Store the absolute path to the root directory, and construct the various link destination paths relative to this reference root directory.

#!/bin/sh

root_dir='/absolute/path/to/root/dir'
provider_tf="${root_dir}/common/provider.tf"
prod_dir="${root_dir}/environments/prod"
module_dir="${prod_dir}/module"

for dest_dir in "${prod_dir}" "${module_dir}"; do
  ln --symbolic --relative "${provider_tf}" "${dest_dir}/"
done

CodePudding user response：

The OS actually doesn't care at all what your symlink points to. You can do

ln -s /no/such/path brokenlink

and similarly you can

ln -s ../../../common/provider.tf environments/prod/module/provider.tf

regardless of what your current directory is; the symlink will be resolved relative to the directory where you created it.

Unfortunately, ln only allows you to create a single symlink at a time; but with this, you could also create the links from the project's base directory with a simple loop.

for dest in environment environment/prod
do
    ln -s $PWD/common/provider.tf "$dest"
done

The variable $PWD is a Bash built-in (but not available in sh, which you had also originally tagged your question as; perhaps see also Difference between sh and bash) - you could also add a --relative option to convert it to a relative symlink like Léa proposes if you have GNU ln (but again, this is not properly portable to POSIX ln). (If you need POSIX/sh portability, you can add PWD=$(pwd) before the loop.)