pstow

A spiritual reimplementation of GNU Stow, for tinkerers.

A fancy way to softlink your dotfiles to their intended destination.

Intent

This started as a personal side project in order to facilitate the easy one-line deployment of my entire dotfile structure.

A critical feature (redirects) was added as a personal requirement.
I decided to open-source this utility in sight of the fact that people might require the same solution I did. Keep in mind there are valid alternatives to this utility; keep your options open.

Features

• .stowconfig
• Lightweight.
• Clear-cut & simple to use.
• Ignorables, meaning files & directories that will be excluded.
• Redirectables, meaning files that will be redirected (moved) to a virtual directory of your own choosing.
  You can see this in use in my dotfiles.
• Dynamic targets (supported through redirects.)
• Multiple targets (supported through redirects.)
• Conditional cases, supported through if-directives You may opt to avoid conforming to a 1:1 relationship between your dotfiles' directory structure & their target, unlike a bare git repo, which is often the most common "recipe".

Zero-to-hero for .stowconfig & interactive demo

prerequisites

• python3.12

demo

First, clone the repository:

git clone git@github.com:gerelef/pstow.git && cd ./pstow

We need a workspace to try out pstow.
Create a mock playground by running ./generate-mock-dotfiles.py while inside the pstow directory:

./generate-mock-dotfiles && cd ./dotfiles

Now you should be inside the ~/.../pstow/dotfiles directory. Great! We're ready to get started.
Let's start with a dry run; this will display what is ready to be symlinked to the target of your choosing. It won't affect your filesystem!
We're going to be explicit here about our destination (--target <path>):

~/.../dotfiles $ ../pstow.py --target ~ status
# ... output too long to print here

Nice.
When running pstow with the status subcommand, we're going to get a display of whatever would be linked,
in relation to the root dotfiles directory. We're getting alot of output, mostly from directories we definitely don't want to symlink.
Lets change that! We're going to be verbose, manually excluding everything, once again from the shell:

 ~/.../dotfiles $ ../pstow.py --exclude .config/ .git/ scripts/ manpages/ --target ~ status
  dotfiles/
 dotfiles/
───> .gitconfig
───> .has-run
───> .shell-requirements
───> .stowconfig
───> baraction.sh
───> cju.conf
───> config.conf
───> dui.yml
───> macho-gui.sh
───> macho.sh
WARNING: Aborting.

The status output was whatever was in the root dotfiles directory.
Great! This means we can explicitly, on-demand, exclude whatever files we don't want to symlink manually.
However, it'd be alot cooler if we could do this automatically rather than remembering random shell incantations...
Let's start by creating a .stowconfig in the root dotfiles directory.
If it exists, don't worry! Just overwrite the contents & paste the following:

*.md
.git/
manpages/
scripts/
.config/

Now let's run the first command we run originally:

 ~/.../dotfiles $ ../pstow.py --target ~ status
 dotfiles/
───> .gitconfig
───> .has-run
───> .shell-requirements
───> .stowconfig
───> baraction.sh
───> cju.conf
───> config.conf
───> dui.yml
───> macho-gui.sh
───> macho.sh
WARNING: Aborting.

Our output is the same as if we manually excluded the aforementioned directories.
This means our pstow configuration works!
Now, lets try to exclude our .*rc files located in ./scripts.
Update .stowconfig so that it looks like the following & rerun with ../pstow.py --target ~ status:

*.md
.git/
manpages/
.config/
scripts/
!!scripts/.*rc

 ~/.../dotfiles $ ../pstow.py --target ~ status
 dotfiles/
───> .gitconfig
───> .has-run
───> .shell-requirements
───> .stowconfig
───> baraction.sh
───> cju.conf
───> config.conf
───> dui.yml
───> macho-gui.sh
───> macho.sh
───> scripts/
───────> .bashrc
───────> .jwmrc
───────> .nanorc
───────> .vimrc
───────> .zshrc
WARNING: Aborting.

We have successfully un-ignored our .*rc files!
Keep in mind, is that since the file is read top-to-bottom,
and the evaluations are being done on a line-by-line basis,
if you write the un-ignore line before the ignore declaration, the file won't be unignored.
The following step is to move them to the root dotfile directory.

Typically, people recommend a bare git repo, but that couples the dotfile structure to the filesystem structure.
This makes things coupled, and difficult to keep track of;
most people end up with endless nestings, when they just want a couple of files, 3 or 4 paths deeper, or a file one level up.

To deal with this common issue, we're going to learn about redirects, also referred to as virtual files.
Let's start by adding a redirect section!
Update your .stowconfig so that it looks like this & rerun as usual:

*.md
.git/
manpages/
.config/
scripts/
!!scripts/.*rc

[redirect]
scripts/.*rc ::: .

 ~/.../dotfiles $ ../pstow.py --target ~ status
 dotfiles/
───> .gitconfig
───> .has-run
───> .shell-requirements
───> .stowconfig
───> baraction.sh
───> cju.conf
───> config.conf
───> dui.yml
───> macho-gui.sh
───> macho.sh
───> .bashrc
───> .jwmrc
───> .nanorc
───> .vimrc
───> .zshrc
WARNING: Aborting

As you can see, we have [redirect]ed every .*rc file one level up,
the same level as the .stowconfig, denoted by the dot (.)
Files cannot be renamed this way, only moved.
This is a hard limitation; you cannot change the destination name.
It's always assumed the destination is a directory, and will be created on demand if it doesn't exist, when applying pstow.

Suppose we have a case, we're going to use a firefox user.js config file as a real world scenario,
where we know what the path's going to look like, but since the directory name is automatically generated, we cannot pinpoint a redirect to any specific path.
To solve this problem, globbable redirects have been added.
The path will be inferred by the target we set, so for the following step, make sure the following path exists: ~/.mozilla/firefox/*.default-release*/

Let's edit our .stowconfig again; we'll redirect the .jwmrc to the mozilla config directory:

*.md
.git/
manpages/
.config/
scripts/
!!scripts/.*rc

[redirect]
scripts/.*rc ::: .
scripts/.jwmrc ::: .mozilla/firefox/*.default-release*/

 dotfiles/
───> .gitconfig
───> .has-run
───> .shell-requirements
───> .stowconfig
───> baraction.sh
───> cju.conf
───> config.conf
───> dui.yml
───> macho-gui.sh
───> macho.sh
───> .bashrc
───> .nanorc
───> .vimrc
───> .zshrc
───> .mozilla/
───────> firefox/
───────────> h2rjlo7a.default-release/
───────────────> .jwmrc
WARNING: Aborting.

Success! We can dynamically redirect anything we want, however deep we want, with full support for multiple targets.
If we wanted to be a little more generous, and insert our file in every directory inside the firefox dir,
here's how we'd do that:

*.md
.git/
manpages/
.config/
scripts/
!!scripts/.*rc

[redirect]
scripts/.*rc ::: .
scripts/.jwmrc ::: .mozilla/firefox/*/

 ~/.../dotfiles $ ../pstow.py --target ~ status
 dotfiles/
───> .gitconfig
───> .has-run
───> .shell-requirements
───> .stowconfig
───> baraction.sh
───> cju.conf
───> config.conf
───> dui.yml
───> macho-gui.sh
───> macho.sh
───> .bashrc
───> .nanorc
───> .vimrc
───> .zshrc
───> .mozilla/
───────> firefox/
───────────> Crash Reports/
───────────────> .jwmrc
───────────> Pending Pings/
───────────────> .jwmrc
───────────> installs.ini/
───────────────> .jwmrc
───────────> h2rjlo7a.default-release/
───────────────> .jwmrc
───────────> profiles.ini/
───────────────> .jwmrc
───────────> zhqudbkl.default/
───────────────> .jwmrc
WARNING: Aborting.

Now, we'll start dealing with one of the last topics regarding .stowconfig: if-directives. As of writing, there are four possible directives:

• if-pkg
• if-not-pkg
• if-profile
• if-not-profile

The first directive checks for the existence of packages in non-interactive $PATH.
A subshell is never opened, so it's (probably) secure to be as wack as you want.
You can include multiple packages to check.
The second directive checks the inverse, i.e. the absence of packages in $PATH.
The third directive checks the current active profile, and runs if it is.
The fourth directive checks the current active profile, and runs if it isn't.
Example usage; update your .stowconfig to look like this, & run as usual:

*.md
.git/
manpages/
.config/
scripts/
!!scripts/.*rc
[if-not-pkg:::nano]
    scripts/.nanorc
[end]
[if-not-pkg:::vim]
    scripts/.vimrc
[end]
[if-pkg:::zsh some-other-package]
    !!scripts/.zshrc
[end]

[redirect]
scripts/.*rc ::: .
scripts/.jwmrc ::: .mozilla/firefox/*/

 ~/.../dotfiles $ ../pstow.py --target ~ status
WARNING: Couldn't fulfill condition for [if-not-pkg:::nano]. Skipping block contents...
Applying [if-not-pkg:::vim] entry: scripts/.vimrc
WARNING: Couldn't fulfill condition for [if-pkg:::zsh some-other-package]. Skipping block contents...
 dotfiles/
───> .gitconfig
───> .has-run
───> .shell-requirements
───> .stowconfig
───> baraction.sh
───> cju.conf
───> config.conf
───> dui.yml
───> macho-gui.sh
───> macho.sh
───> .bashrc
───> .nanorc
───> .zshrc
───> .mozilla/
───────> firefox/
───────────> Crash Reports/
───────────────> .jwmrc
───────────> Pending Pings/
───────────────> .jwmrc
───────────> installs.ini/
───────────────> .jwmrc
───────────> pkziaq2y.default-release/
───────────────> .jwmrc
───────────> profiles.ini/
───────────────> .jwmrc
───────────> xpqxabjk.default/
───────────────> .jwmrc
WARNING: Aborting.

As you can see, since I don't have vim on my $PATH, .vimrc is automatically ignored!
Of course, nano exists, but .zhrc AND some-other-package do not, so their rules are not applied.

Finally, we'll talk about profiles & their directives.

Suppose I wouldn't want my .jwmrc config file in the firefox directories when deploying this on my work partition or PC.
Let's edit our .stowconfig accordingly:

*.md
.git/
manpages/
.config/
scripts/
!!scripts/.*rc
[if-not-pkg:::nano]
    scripts/.nanorc
[end]
[if-not-pkg:::vim]
    scripts/.vimrc
[end]
[if-pkg:::zsh some-other-package]
    !!scripts/.zshrc
[end]

[redirect]
scripts/.*rc ::: .

[if-not-profile:::work]
    scripts/.jwmrc ::: .mozilla/firefox/*/
[end]

...and run like this, setting the current profile in the process:

 ~/.../dotfiles $ ../pstow.py --profile work --target ~ status
WARNING: Couldn't fulfill condition for [if-not-pkg:::nano]. Skipping block contents...
Applying [if-not-pkg:::vim] entry: scripts/.vimrc
WARNING: Couldn't fulfill condition for [if-pkg:::zsh some-other-package]. Skipping block contents...
WARNING: Couldn't fulfill condition for [if-not-profile:::work]. Skipping block contents...
 dotfiles/
───> .gitconfig
───> .has-run
───> .shell-requirements
───> .stowconfig
───> baraction.sh
───> cju.conf
───> config.conf
───> dui.yml
───> macho-gui.sh
───> macho.sh
───> .bashrc
───> .jwmrc
───> .nanorc
───> .zshrc
WARNING: Aborting.

When running with --profile work, the .jwmrc won't be applied,
meaning we can keep one configuration file for multiple deployments in different systems!

This concludes the entire tutorial regarding pstow; next step is looking at the --help prompt,
and checking out deployments in production. A good starter for the latter would be my personal dotfiles.

--help

usage: A spiritual reimplementation of GNU Stow, but simpler, for tinkerers. [-h] [--source SOURCE] [--target TARGET] [--enforce-integrity] [--force] [--yes] [--overwrite-others]
                                                                             [--exclude EXCLUDE [EXCLUDE ...]] [--profile PROFILE] [--no-parents] [--no-redirects]
                                                                             {status} ...

positional arguments:
  {status}
    status              Echo the current status of the stow source.

options:
  -h, --help            show this help message and exit
  --source SOURCE, -s SOURCE
                        Source directory links will be linked from.
  --target TARGET, -t TARGET
                        Target (destination) directory links will be linked to.
  --enforce-integrity, -i
                        Enforce integrity of any .stowconfig encountered; a.k.a. stop at any error.
  --force, -f           Force overwrite of any conflicting file. This WILL overwrite regular files!
  --yes, -y             Automatically assume 'yes' for any user prompt. Dangerous flag, possibly destructive!
  --overwrite-others, -o
                        Ovewrite links/files owned by other users than the current one. Default behaviour is to not overwrite files not owned by the current user. Functionally the same as
                        --no-preserve-root in the rm command.
  --exclude EXCLUDE [EXCLUDE ...], -e EXCLUDE [EXCLUDE ...]
                        Exclude (ignore) a specific directory when copying the tree. Multiple values can be given. Symlinks are not supported as exclusion criteria.
  --profile PROFILE, -p PROFILE
                        Profile to use when loading .stowconfigs.This will affect all if-profile and if-not-profile blocks accordingly.
  --no-parents, -n      Don't make parent directories as we traverse the tree in destination, even if they do not exist.
  --no-redirects, -r    Don't respect redirects in any encountered stowconfig.

.stowconfig exhaustive structure

The first section is always the [ignore] section, as implied by the lack of header.
The second section [redirect] is inferred from the explicit header.

"Unignores" should be evaluated after a file has been ignored, otherwise they will not apply.
They're evaluated as-is; no reordering happens on any level, so the onus is on you to make sure they work right.

Comments are allowed after a newline; they cannot be inlined.

Syntax for redirect entries must match the following regex to be valid: \"?(.+)\"?\s+(:::)\s+\"?(.+)\"?
The redirect destination must be a directory. This is a semantic limitation, and will not be raised.

Profile is considered default if omitted.

The following is the exhaustive syntax of a .stowconfig file:

// [ignore] header is not necessary, implied by the lack of header at the start of the file
*.md
.stowconfig
.git/

scripts/*

[if-profile:::work hobby]
    // unignore work config
    !!scripts/.mywork
    // unignore all hobby dotfiles
    !!scripts/*hobby*
[end]
[if-not-profile:::default]
    // if on any other profile other than default, ignore the .someThing file  
    .config/.someThing
[end]
// if vim and nano are currently installed, symlink their files
[if-pkg:::vim nano]
    !!scripts/.vimrc 
    !!scripts/.nanorc
[end]
[if-not-pkg:::delta]
    // if git-delta is not currently installed, go ahead and ignore it's .gitconfig
    scripts/.gitconfig-gitdelta
[end]

[redirect]
myfile ::: .
some/other/file ::: some/

[if-profile:::testing]
    testing/* ::: something/else/*/
[end]

More details on if-directives:

// all packages MUST exist in non-interactive, non-login shell (AND)
[if-pkg:::pkg1 pkg2 pkg3 ...]
...
[end]
// all packages MUST NOT exist in non-interactive, non-login shell (AND)
[if-not-pkg:::pkg1 pkg2 pkg3 ...]
...
[end]
// current profile MUST exist in the profile list (CONTAINS) 
[if-profile:::profile1 profile2 ...]
...
[end]
// current profile MUST NOT exist in the profile list (NOT CONTAINS)
[if-not-profile:::profile1 profile2 ...]
...
[end]

Supported platforms

GNU/Linux only.