Deploying from circleci2.0 to Heroku

Resources:

• circleci 2.0 docs
• Managing SSH Keys on Heroku

Steps:

Prerequisites:

• Heroku CLI installed on your computer
• A project deployed to Heroku
• A project in circleci set up using circleci version 2.0

1. Edit .circleci/config.yml

• Nested under steps (after you run tests, etc.) add:

- run: bash .circleci/setup-heroku.sh
- add_ssh_keys:
    fingerprints:
      - $HEROKU_SSH_FINGERPRINT
- deploy:
    name: Deploy to Heroku if tests pass and branch is master
    command: |
      if [ "${CIRCLE_BRANCH}" == "master" ]; then
        git push --force [email protected]:$HEROKU_APP_NAME.git HEAD:refs/heads/master
        <any other necessary commands for heroku deployment you might need can go here>
      fi

2. Create a new file .circleci/setup-heroku.sh with the following:

#!/bin/bash
ssh-keyscan -H heroku.com >> ~/.ssh/known_hosts
# If you need access to the heroku CLI to run heroku commands in the deploy step add these lines:
# mkdir -p /usr/local/lib /usr/local/bin
# tar -xvzf heroku-linux-amd64.tar.gz -C /usr/local/lib
# ln -s /usr/local/lib/heroku/bin/heroku /usr/local/bin/heroku

cat > ~/.netrc << EOF
machine api.heroku.com
  login $HEROKU_LOGIN
  password $HEROKU_API_KEY
EOF

cat >> ~/.ssh/config << EOF
VerifyHostKeyDNS yes
StrictHostKeyChecking no
EOF

3. add Environment Variables to circleci

Key Name	Where to get it
HEROKU_API_KEY	Found in Heroku Account Settings: It is your individual API Key even if it is a company Account
HEROKU_LOGIN	Your Heroku login e.g: [email protected]
HEROKU_APP_NAME	The name of your app on Heroku

4. Create SSH keys

• Create a SSH key locally $ ssh-keygen -t rsa
• Copy the fingerprint returned from ^^^^
• Add another environment variable in circleci
  • HEROKU_SSH_FINGERPRINT
    • paste the copied fingerprint as the value
• Add the public SSH to Heroku $ heroku keys:add
• Open ~/.ssh/id_rsa (or wherever you saved your ssh key) and copy key including -----Begin RSA PRIVATE KEY ---- and -----End RSA PRIVATE KEY------
• Add SSH private key to circleci
  • in project settings -> SSH Permissions -> Add SSH Key
  • Hostname = git.heroku.com
  • Paste the private key and click Add SSH Key

5. Celebrate (trigger circleci on your master branch and watch it deploy!)