Configure Elixir app on Travis CI

setup_elixir_app_on_travis_ci.md

Configure Elixir app on Travis CI

Setup Build

1. Create .travis.yml file in the base dir
2. Enter the following content:

language: elixir
elixir:
  - 1.2
otp_release:
  - 18.0
sudo: false

3. Commit
4. Goto travisci.com and enable your project
5. Profit!

Setup Deployment

Sources:

• https://github.com/bitborn/tweet.py/blob/master/Readme.md
• https://www.digitalocean.com/community/questions/dokku-add-new-ssh-key

###On your local machine:

Generate a new key pair

ssh-keygen

This will prompt for a two things, namely:

• The output path (use /home/<username>/.ssh/<app_name>)
• A passphrase (leave it empty)

Now copy the key to the server

cat ~/.ssh/<app_name>.pub | ssh <mydomain> "sudo sshcommand acl-add dokku <app_name>"

Now we can test pushing a project

Since we're not using the default key pair. We'll have to do a bit of local configuration.

Add the following to ~/.ssh/config

Host <app_name>.<mydomain>
  HostName <app_name>.<mydomain>
  User root
  PreferredAuthentications publickey
  IdentityFile ~/.ssh/<app_name>

Note that we're using the private key not <app_name>.pub

Add a remote to the project

git remote add dokku dokku@<app_name>.<mydomain>:<app_name>

Then push

git push dokku master

Install the travis gem

gem install travis

Create a travis directory

mkdir .travis

Create a pem file

openssl rsa -in ~/.ssh/<app_name> -outform pem > .travis/<app_name>.pem

Hide it from git

echo .travis/<app_name>.pem >> .gitignore

Log into travis

travis login --auto

Encrypt the key

travis encrypt-file .travis/<app_name>.pem --add

For some reason travis adds the encrypted key to the root directory lets move that

mv <app_name>.pem.enc .travis

Edit the .travis.yml file to reflect the move. Change -in <app_name>.pem.enc to -in .travis/<app_name>.pem.enc

Add a after_success: section like so

- chmod 600 .travis/<app_name>.pem
- mkdir -p ~/.ssh
- cp .travis/<app_name>.pem ~/.ssh
- cat .travis/host >> ~/.ssh/config
- git remote add production dokku@<mydomain>:<app_name>
- test $TRAVIS_PULL_REQUEST == "false" && test $TRAVIS_BRANCH == "master" && git push dokku master

Then create a .travis/host to make travis use the correct key:

Host <server address>
    StrictHostKeyChecking no
    IdentityFile ~/.ssh/<app_name>.pem

Then register your project on travis-ci.org and push away.