Dotfile Status Script

dotstat.sh

#!/usr/bin/env/bash

# This is a simple script to check the current local/remote status of your
# dotfiles, and prompt to update them if needed.
#
# Update the contents of the 'sync_dotfiles' function below to change the
# method for performing dotfile updates.
#
# You must set the 'LOCAL_DOTFILES_REPOSITORY' environment variable
# to point to the path of your local dotfiles repo prior to executing this script.
#
# The core portion of this script is taken from a general solution for checking
# the status of local/remote git repos posted by Neil Mayhew on StackOverflow:
#   http://stackoverflow.com/a/3278427/1428743

# Syncs dotfile changes
# NOTE TO USER:
# Modify this function to use your desired mothod of syncing dotfiles
function sync_dotfiles() {
    # Currently using updot (https://github.com/ntpeters/updot) for dotfile sync

    # Ensure Python is installed
    if ! prog_loc="$(type -p "python")" || [ -z "$prog_loc" ] || [ "$prog_loc" == *"not found"* ]; then
        echo "ERROR: Python does not exist in path! Updot requires Python. Please ensure Python is installed, and try again."
        return

    fi

    # Try executing updot from its default location
    if [ -f $HOME/.updot/updot.py ]; then
        python $HOME/.updot/updot.py
    else
        echo "ERROR: updot not found! Aborting sync!"
    fi
}

# Checks the status of local and remote dotfiles repos to determine if they
# need to be synced up.
function check_dotfiles_status() {
    # Make sure the path we were given is a git repo
    if [ ! -d ./.git ]; then
        echo "ERROR: Provided dotfile directory is not a git repository!"
        return
    fi

    # Check if git is available
    if ! prog_loc="$(type -p "git")" || [ -z "$prog_loc" ] || [ "$prog_loc" == *"not found"* ]; then
        echo "ERROR: Git does not exist in path! Please ensure git is installed, and try again."
        return
    fi

    # Check for active internet connection
    echo -e "GET http://google.com HTTP/1.0\n\n" | nc google.com 80 > /dev/null 2>&1
    if [ $? -eq 1 ]; then
        echo "ERROR: Failed to get status of remote dotfiles. No active internet connection detected!"
        return
    fi

    # Get remote branch info
    $(git fetch > /dev/null 2>&1)

    # Retrieve hashes from git
    local LOCAL=$(git rev-parse @)
    local REMOTE=$(git rev-parse @\{u\})
    local BASE=$(git merge-base @ @\{u\})

    # Check for uncommitted changes
    $(! git diff-index --quiet HEAD --)
    local UNCOMMITTED=$?

    # Flag to determine if an update may need to be done
    local update=true

    # Determine status of dotfiles
    if [ -z $LOCAL ] || [ -z $REMOTE ] || [ -z $BASE ]; then
        echo "ERROR: Failed to get status of local dotfiles!"
        update=false
    elif [ $UNCOMMITTED = 0 ]; then
        echo "Local dotfiles have uncommitted changes."
    elif [ $LOCAL = $REMOTE ]; then
        echo "Dotfiles up-to-date."
        update=false
    elif [ $LOCAL = $BASE ]; then
        echo "Remote dotfiles have changed."
    elif [ $REMOTE = $BASE ]; then
        echo "Local dotfiles have changed."
    else
        echo "WARNING: Local and remote dotfiles have diverged. You may experience merge conflicts!"
    fi

    # See if the user wants to sync dotfiles
    if $update; then
        read -p "Sync dotfiles now? [y/n] " -n 1 -r
        echo
        if [[ $REPLY =~ ^[Yy]$ ]]; then
            echo
            # Execute the defined method of syncing dotfiles
            sync_dotfiles
        fi
    fi
}

# Check if other shell instances are currently running
# Only check dotfile status on initial shell open
cur_shell_instances=$(pgrep -f `ps -p $$ -ocomm= | cut -d'/' -f 3` | wc -l | tr -d ' ')
default_shell_instances=$(pgrep -f ${SHELL##*/} | wc -l | tr -d ' ')
total_shell_instances=$(( $cur_shell_instances + $default_shell_instances ))
if (( $total_shell_instances > 1 )); then
    exit 1
fi

# Ensure a path to the local dotfiles repo has been provided
if [ -z ${LOCAL_DOTFILES_REPOSITORY+x} ]; then
    echo "ERROR: Must set the 'LOCAL_DOTFILES_REPOSITORY' variable with path to your dotfiles directory!"
else
    # Ensure path to dotfiles repo has expanded tilde for home dir
    # Not sure how portable this method is...
    local_dotfiles_repo=$(eval "echo $LOCAL_DOTFILES_REPOSITORY")
    # Check if dotfiles need to be updated
    ( cd ${local_dotfiles_repo} && check_dotfiles_status )
fi