Publish documentation to directory reflecting tag or branch in gh-pages branch

publish.sh

#!/bin/sh

# get current branch and tag
branch=`git symbolic-ref HEAD 2>/dev/null | cut -d"/" -f 3`;
tag=`git describe --tags`;

# if current tag has annotations showing number of commits since tagging, then use current branch
destination="$tag"
if [[ "$tag" == *-* ]]
then
  echo "extra commits since last tag!";
  destination="$branch"
fi
# source and destination will be same, separate variables for clarity
src_tag_or_branch=$destination

echo "destination: $destination"

# then git checkout gh-pages and go to top level dir
git checkout gh-pages && cd $(git rev-parse --show-toplevel)

# then mkdir for current branch or tag
mkdir -p $destination

# then copy doc files to current branch under a directory for current tag/branch
git archive --format=tar --prefix=$destination/ $src_tag_or_branch:docs | tar -xf -

# then commit new docs with message
git add .
git commit -m "updated docs from $src_tag_or_branch for $destination"

# return to original branch
git checkout $branch