deploy.sh

#!/bin/bash
set -e # Exit with nonzero exit code if anything fails

SOURCE_BRANCH="master"
TARGET_BRANCH="gh-pages"

# Pull requests and commits to other branches shouldn't try to deploy, just build to verify
if [ "$TRAVIS_PULL_REQUEST" != "false" -o "$TRAVIS_BRANCH" != "$SOURCE_BRANCH" ]; then
    echo "Skipping deploy"
fi

# Save some useful information
REPO=`git config remote.origin.url`
SSH_REPO=${REPO/https:\/\/github.com\//git@github.com:}
SHA=`git rev-parse --verify HEAD`

# Commit the "changes", i.e. the new version.
cd _book
git init
git config user.name "Travis CI"
git config user.email "mathieu@dutour.me"
git checkout -b gh-pages
touch .nojekyll
git add .
git commit -m 'update book'

# Get the deploy key by using Travis's stored variables to decrypt github_deploy.enc
chmod 600 ../github_deploy
eval `ssh-agent -s`
ssh-add ../github_deploy

# Now that we're all set up, we can push.
git push $SSH_REPO $TARGET_BRANCH --force