update-sources-branch.sh

#!/usr/bin/env bash

# Move contents from this subdirectory into root directory of a repository.
# - Any relative directory could be as a value.
# - Pass "--default" to keep this value and affect on the next.
DIRECTORY="docroot"
# Commit moved content in this branch.
# - Any name can be specified. Branch will be created.
# - Pass "--default" to keep this value and affect on the next.
BRANCH="sources"
# Push commit to a remote.
# - Any name or fully qualified URL of remote can be specified.
# - Pass "--default" to keep this value and affect on the next.
REMOTE="origin"
GITIGNORE=".*
!.git*"

type "realpath" > /dev/null 2>&1

if [ $? -gt 0 ]; then
    realpath()
    {
        # Try to read a symlink.
        local LINK=$(\readlink $1)

        if [ -n "${LINK}" ]; then
            \echo ${LINK}
        else
            local PATH=$(\cd -P -- $(\dirname -- $1) && \pwd -P)

            while [ -h "${PATH}" ]; do
                # 1. Go to the directory with a symlink.
                # 2. Go to the directory to which the symlink points.
                # 3. Get the path.
                PATH=$(\cd $(\dirname -- ${PATH}) && \cd $(\dirname -- $(\readlink ${PATH})) && \pwd)
            done

            \echo ${PATH}/${1##*/}
        fi
    }
fi

arg()
{
    [[ -z "$1" || "$1" == "--default" ]] && \echo $2 || \echo $1
}

################################################################################
# ARGUMENT $1 - path to directory with source code (relative or absolute).
################################################################################

DIRECTORY=$(realpath $(arg $1 ${DIRECTORY}))

if [ ! -d "${DIRECTORY}" ]; then
    \echo "The \"${DIRECTORY}\" path does not exists!"
    \exit 1
fi

################################################################################
# ARGUMENT $2 - the name of one of branches.
################################################################################

BRANCH=$(arg $2 ${BRANCH})

################################################################################
# ARGUMENT $3 - the name of one of remotes or fully qualified URL.
################################################################################

# Try to recognize remote Git server by name.
REMOTE=$(\git remote -v | \grep $(arg $3 ${REMOTE}) | \awk '{print $2}' | \head -n1)

if [ -z "${REMOTE}" ]; then
    # Try to recognize remote Git server by URL.
    \git ls-remote --exit-code ${REMOTE} > /dev/null 2>&1

    # Update variable if remote repository exists.
    if [ $? -eq 0 ]; then
        REMOTE=$3
    fi
fi

# Finally check existence of remote repository.
if [ -z "${REMOTE}" ]; then
    \echo "Unable to recognize \"$3\" Git remote."
    \exit 3
fi

################################################################################
# Process.
################################################################################

TEMPORARY_REPO=/tmp/emptyrepo
BRANCH_EXISTS_LOCAL=false
BRANCH_EXISTS_REMOTE=false

\echo "Clear temporary storage: ${TEMPORARY_REPO}"
\rm -rf ${TEMPORARY_REPO}

\echo "Remote repository: ${REMOTE}"
\echo "Branch: ${BRANCH}"

# Check for local branch.
\git rev-parse --verify ${BRANCH} > /dev/null 2>&1

if [ $? -eq 0 ]; then
    BRANCH_EXISTS_LOCAL=true
fi

if [ -n "$(\git ls-remote --heads ${REMOTE} ${BRANCH})" ]; then
    BRANCH_EXISTS_REMOTE=true
fi

if ${BRANCH_EXISTS_REMOTE}; then
    \echo "Remote branch exists."
    \git clone ${REMOTE} --branch=${BRANCH} ${TEMPORARY_REPO}
    \echo "Copying data from \"${DIRECTORY}\" to \"${TEMPORARY_REPO}\""
    \rsync -ra ${DIRECTORY}/* ${TEMPORARY_REPO}/
    \cd ${TEMPORARY_REPO}
    \git checkout ${BRANCH} > /dev/null 2>&1
else
    # Remove content after latest slash.
    # Example "/var/www/site" => "/var/www".
    COPY_FROM=${DIRECTORY%/*}
    # Remove content before latest slash.
    # Example "/var/www/site" => "site".
    CONTENT_DIR=${DIRECTORY##*/}

    \echo "Not remote nor local branches aren't exists."
    \echo "Copying data from \"${COPY_FROM}\" to \"${TEMPORARY_REPO}\""
    \rsync -ra ${COPY_FROM}/ ${TEMPORARY_REPO}/
    \cd ${TEMPORARY_REPO}
    \echo "Remove all files and directories, except \"${CONTENT_DIR}\" and \".git\", from ${TEMPORARY_REPO}"
    \ls -A | \grep -v "^${CONTENT_DIR}$" | \grep -v "^.git$" | \xargs \rm -rf
    \echo "Move content from \"${CONTENT_DIR}\" to repository root."
    \mv ${CONTENT_DIR}/* ./
    \echo "Generate an empty .gitignore"
    \echo ${GITIGNORE} > .gitignore
    \git checkout -b ${BRANCH}
fi

\git add .
\git commit -m "Automatic commit generated via script."
\git push ${REMOTE} ${BRANCH}