Modern Web Deployment Workflow

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This collection of Ansible playbooks have been designed to simplify deployment of a modern website or web app using Vagrant, Ubuntu, nginx and HTTP/HTTPS. Many tasks have been separated into separate roles, and as much configuration as possible has been abstracted into external variables.

High-level benefits include:

A new server can be up and running with fully deployed code in just a few minutes.
An update to an existing project can be deployed and built in under a minute.
A project can be rolled back to a previously-deployed version in a matter of seconds.
Updates to server configuration can be made in a matter of seconds.
Most server configuration and code updates can be made with zero server downtime.
Code can be tested locally in Vagrant before being deployed to a production server.
Code can be tested on a staging server for QA or final testing before being deployed to a production server.
Server configuration and project deployment can be made to scale to any number of remote hosts.

More specific benefits include:

Almost all server configuration and project deployment information is stored in the project, making it easy to destroy and re-create servers with confidence.
All project maintainer user account information is stored in the project, making it easy to add or remove project maintainers.
SSH agent forwarding allows the remote server to access private GitHub repos without requiring a private key to be copied to the server or for dedicated deployment keys to be configured.
While working locally, the Vagrant box can easily be toggled between development and deployment modes at any time. This allows local changes to be previewed instantly (development) or a specific commit to be built as it would be in production (deployment).
SSL certs can be auto-generated for testing HTTPS in development.
Because the entire deployment workflow is comprised of Ansible playbooks and a Vagrantfile, it can be easily modified to meet any project's needs.

Here are links to the official, original project home page, documentation, Git repository and wiki:

Notes:

Even though Node.js and npm are used in this sample project, with minor edits this workflow can be made to work with basically any programming language, package manager, etc.
This workflow won't teach you how to create an AWS instance. Fortunately, there are already excellent guides for creating a key pair, setting up a security group and launching an instance.
This workflow has been thoroughly tested in Ubuntu 14.04 LTS (trusty). More specifically, with the ubuntu/trusty64 Vagrant image and with the AWS EC2 Ubuntu Server 14.04 LTS AMI. Minor adjustments might need to be made for other providers, while more substantial changes might need to be made for other Ubuntu versions or Linux distributions.
While this workflow has been designed to meet the needs of a typical use case, it might not meet your project's needs exactly. Consider this to be a starting point; you're encouraged to edit the included playbooks and roles!

Overview

Assuming you've already created (or are in the process of creating) a website or web app, you will typically perform these steps when using this workflow.

Ensure the workflow dependencies have been installed on your development machine.
Add and commit the workflow files into your project.
Modify the Ansible variables, playbooks and roles to meet your specific project needs.
Test your project on the local Vagrant box while authoring it. (Optional, but recommended)
Deploy your project to a staging server for QA and final testing. (Optional, but recommended)
Deploy your project to a production server.

Step 1 is usually only done per development machine, steps 2-3 are usually only done per project, and steps 4-6 will be repeated throughout the life of your project as you make and test changes and deploy new versions of your website or web app.

Dependencies

The following will need to be installed on your local development machine before you can use this workflow. All versions should be the latest available unless otherwise specified.

Ansible (version 1.9.2)
- Install ansible via apt (Ubuntu), yum (Fedora), homebrew (OS X), etc. See the Ansible installation instructions for detailed, platform-specific information.
VirtualBox
- Download (All platforms)
- Install virtualbox via homebrew cask (OS X)
Vagrant
- Download (All platforms)
- Install vagrant via homebrew cask (OS X)
vagrant-hostsupdater
- Install with vagrant plugin install vagrant-hostsupdater (All platforms)

Notes:

Ansible doesn't really work in Windows. But it works great in OS X and Linux, so be sure to use one of those operating systems for development.

Initial Setup

Copy this project's files so that the deploy directory is in the root of your project Git repository. Be sure to copy recursively and preserve file modes, eg. executable, so that the bash helper script continues to work. The Vagrantfile and ansible.cfg file should be placed in your project root directory, not the deploy directory.

Also, be sure to add .vagrant to your project's .gitignore file so that directory's contents, which are auto-generated by Vagrant, aren't committed with your project's source.

Ansible

At the core of this workflow is Ansible, an IT automation tool. Ansible aims to be simple to configure and easy to use, while being secure and reliable. In this workflow, Ansible is used to configure systems and deploy software.

Ansible Configuration

Ansible Variables

Much of this workflow's behavior can be configured via Ansible variables.

ansible/group_vars/all.yml - variables global to all playbooks and roles

Host-specific settings may be defined in host-named files in the host_vars directory and will override global values.

ansible/host_vars/vagrant - variables specific to the vagrant inventory host

Variables may be overridden when a playbook is run via the --extra-vars command line option. These variables are noted in the preceding files as EXTRA VARS.

See the Ansible variables documentation for more information on variables, variable precedence, and how {{ }} templates and filters work.

Ansible Inventory

These files contain the addresses of any servers to which this project will be deployed. Usually, these addresses will be fully qualified domain names, but they may also be IPs. Each inventory file may contain a list of multiple server FQDNs or IPs, allowing a playbook to be deployed to multiple servers simultaneously, but for this workflow, each inventory file will list a single server.

Like with host variables, settings defined here will override those defined in the global variables and group variables files. For example, in the staging inventory, the site_fqdn variable can be set to the staging server's FQDN, allowing nginx to respond to requests made to its FQDN instead of the production server's FQDN.

Unless the variable is a server name-specific override like site_fqdn or ansible_ssh_host, it should probably be defined in host variables.

Ansible Playbooks

Ansible playbooks are human-readable documents that describe and configure the tasks that Ansible will run on a remote server. They should be idempotent, allowing them to be run multiple times with the same result each time.

The following playbooks are included in this workflow:

provision playbook
configure playbook
deploy playbook
vagrant-link playbook
init playbook

For more detailed information on what each playbook actually does and how it will need to be configured, be sure to check out the description for each role that playbook includes.

provision playbook

Provision server. This playbook must be run when a server is first created and is typically only run once. It may be run again if you make server-level changes or need to update any installed apt modules to their latest versions. If you were creating a new AMI or base box, you'd do so after running only this playbook.

Playbook: ansible/provision.yml
Roles: base

configure playbook

Configure server. This playbook is run after a server is provisioned but before a project is deployed, to configure the system, add user accounts, and setup long-running processes like nginx, postgres, etc.

Playbook: ansible/configure.yml
Roles: configure, users, nginx

deploy playbook

Clone, build, and deploy, restarting nginx if necessary. This playbook must be run after provision and configure, and is used to deploy and build the specified commit (overridable via extra vars) on the server. Running this playbook in Vagrant will override the vagrant-link playbook, and vice-versa.

Playbook: ansible/deploy.yml
Roles: deploy

vagrant-link playbook

Instead of cloning the Git repo and building like the deploy playbook, this playbook links your local working project directory into the Vagrant box so that you can instantly preview your local changes on the server, for convenience while developing. While in this mode, all building will have to be done manually, at the command line of your development machine. Running this playbook will override the deploy playbook, and vice-versa.

Playbook: ansible/vagrant-link.yml

init playbook

This playbook saves the trouble of running the provision, configure and vagrant-link playbooks individually, and is provided for convenience. After vagrant up, this playbook will be run on the new Vagrant box.

Playbook: ansible/init.yml

Ansible Roles

There are multiple ways to organize playbooks, and while it's possible to put all your tasks into a single playbook, it's often beneficial to separate related tasks into "roles" that can be included in one or more playbooks, for easy reuse and organization.

The following roles are used by this workflow's playbooks:

base role
configure role
nginx role
users role
deploy role

base role

Get the box up and running. These tasks run before the box is configured or the project is cloned or built. All system dependencies should be installed here.

Apt keys, apt ppas, apt packages and global npm modules can be configured in the PROVISIONING section of the global variables file. If you need custom packages or modules to be installed, specify them there.

Don't be afraid to modify these tasks. For example, if your project doesn't use npm, just remove the npm tasks.

configure role

Configure the box. This happens after the base initialization, but before the project is cloned or built.

nginx role

Generate nginx config files (and ssl configuration, if ssl was specified), rolling back changes if any part of the config is invalid.

The public site path, ssl and ssl cert/key file locations can be configured in the WEB SERVER section of the global variables file. If you want to override any settings for just Vagrant, you can do so in host variables.

By default, nginx is configured to serve a website with a custom 404 page. However, if you want to redirect all requests to index.html (eg. for a web app), you should modify the site.conf template per the inline comments. For more involved customization, read the nginx documentation.

If you enable SSL for production or staging, you will need to supply your own signed SSL cert/key files and put them on the remote server via AWS CloudFormation, cloud-init, or you can copy them manually before provisioning, or this role will fail.

If you choose to enable SSL for vagrant, self-signed SSL cert/key files will be generated for you automatically if they don't already exist. In this case, your website or web app will work, but you will have to click past a SSL certificate warning before viewing it.

users role

In development (localuser.yml), create an account for the currently logged-in user, and copy their public key to the server. This makes it possible to run other playbooks without specifying a user or private key on the command line.

In production (users.yml), ensure all users have been added, along with any public keys. If any user's state is absent, they will be removed. If any keys are removed, they will be deleted. In a development environment, make sudo passwordless, for convenience.

User accounts, passwords and public keys can be configured in the USERS section of the global variables file.

deploy role

Clone the repo and check out the specified commit unless it has already been checked out. When done, symlink the specified commit to make it go live, and remove old clones to free up disk space.

The Git repo URL, deployment paths, number of recent deployments to retain and build info file path can be configured in the DEPLOY section of the global variables file.

The following variables defined in the DEPLOY EXTRA VARS section of the same file may be overridden on the ansible-playbook command line in the format --extra-vars="commit=mybranch force=true".

var	default	description
`remote`	`bocoup`	Specify any remote (typically a github user).
`commit`	`master`	Specify any ref (eg. branch, tag, SHA) to be deployed. This ref must be pushed to the remote `git_repo` before it can be deployed.
`force`	`false`	Clone and build the specified commit SHA, regardless of prior build status.
`local`	`false`	Use the local project Git repo instead of the remote `git_repo`. This option only works with the `vagrant` inventory, and not with `staging` or `production`.

The build.yml file contains all the build tasks that need to be run after your project is cloned, eg. npm install, npm run build. Don't be afraid to modify these tasks. Your project's build process might need to be different than what's here, so adjust accordingly!

Vagrant

Vagrant allows you to isolate project dependencies (like nginx or postgres) in a stable, disposable, consistent work environment. In conjunction with Ansible and VirtualBox, Vagrant ensures that anyone on your team has access to their own private, pre-configured development server whenever they need it.

If you only want to deploy to remote production or staging servers, you can just install Ansible and skip VirtualBox and Vagrant, which are only used to create the local development server.

Configuring Vagrant

The ../Vagrantfile file at the root of the repo contains the project's Vagrant configuration. Be sure to specify an appropriate hostname alias for the Vagrant box here.

Using Vagrant

Once the Vagrantfile and Ansible variables, playbooks and roles have been customized to meet your project's needs, you should be able to run vagrant up to create a local, fully-provisioned Vagrant server that is accessible in-browser via the hostname alias specified in the Vagrantfile. If you're asked for your administrator password during this process, it's so that the hostsupdater plugin can modify your /etc/hosts file.

If you change the Ansible configuration, running vagrant provision will re-run the Ansible playbooks. If you make drastic changes to the Ansible configuration and need to recreate the Vagrant server (which is often the case), you can delete it with vagrant destroy. If you do this, be sure to let collaborators know too!

See the Vagrant Ansible provisioner documentation for more information.

Using SSH with Vagrant

Vagrant provides the vagrant ssh command which allows you to connect to the Vagrant box via its built-in vagrant user. While this is convenient for some basic development tasks, once provisioned, you should connect to the Vagrant box using the user account created by the users role. This will ensure that the ansible-playbook command, which uses ssh internally, will work, allowing you to deploy.

To connect to Vagrant in this way, use the ssh command along with the hostname alias defined in the Vagrantfile. Eg, for this example project, the command would be ssh forums-tessel-io.loc.

Also, adding a section like this to your ~/.ssh/config file will prevent SSH from storing Vagrant box keys in ~/.ssh/known_hosts and complaining about them not matching when a Vagrant box is destroyed and recreated. Do not do this for production servers. This is only safe for private, local virtual machines!

Deploying

Once you've customized Ansible variables, playbooks and roles and committed your changes to the Git repository configured in global variables, you may run the ansible-playbook command or the included playbook helper script to run any playbook on any inventory host.

Command Line Flags

Note that the following flags apply to both ansible-playbook and the included playbook helper script.

--help - Display usage information and all available options; the list here contains only the most relevant subset of all options.
--user - Connect to the server with the specified user. If a user isn't specified, the currently logged-in user's username will be used.
--ask-become-pass - If the remote user account requires a password to be entered, you will need to specify this option.
--private-key - If the remote user account requires a private key, you will need to specify this option.
--extra-vars - Values that override those stored in the ansible configuration in the format --extra-vars="commit=mybranch force=true".
-vvvv - Display verbose connection debugging information.

Production and Staging Notes

Once the users role has run successfully, assuming your user account has been correctly added to it, you should be able to omit the --user and --private-key command line flags. However, until the users role has run at least once:

the --user flag will need to be specified. For the default AWS EC2 Ubuntu AMI, use --user=ubuntu.
the --private-key flag will need to be specified. For AWS, specify --private-key=/path/to/keyfile.pem where keyfile.pem is the file downloaded when creating a new key pair in AWS. Do not store this private key in your project Git repo!

The default AWS ubuntu user doesn't require a password for sudo, but user accounts added via the users role do, so be sure to specify the --ask-become-pass flag when you omit the --user command line flag.

Vagrant Notes

specify --user=vagrant, which is the default user created for the Vagrant box.
specify --private-key=.vagrant/machines/vagrant/virtualbox/private_key, which is where the private key file for user vagrant is generated during vagrant up.

Additionally, you should never need to use the --ask-become-pass flag in Vagrant, once passwordless sudo has been enabled via the configure role. This is done for convenience.

Playbook helper script

While you may run the ansible-playbook command manually, the run-playbook.sh bash script has been provided to facilitate running ansible-playbook.

Usage: run-playbook.sh playbook[.yml] inventory [--flag ...] [var=value ...]

   playbook  playbook file in deploy/ansible/, the .yml extension is optional.
  inventory  inventory host file in deploy/ansible/inventory/.
     --flag  any valid ansible-playbook flags, Eg. --help for help, -vvvv for
             connection debugging, --user=REMOTE_USER to specify the remote
             user, --ask-become-pass to prompt for a remote password, etc.
  var=value  any number of ansible extra vars in the format var=value.

Notes

Flags and vars must be specified after both playbook and inventory.
All arguments specified after playbook and inventory not beginning with - or -- will be treated as extra vars.
If a non-vagrant inventory host is specified, unless the ubuntu user is specified, the --ask-become-pass flag will be automatically added to the command.
You may pass flags to this scripts as you would to ansible-playbook. Eg. --help for help, -vvvv for connection debugging, --user=REMOTE_USER to specify the remote user, --ask-become-pass to prompt for a remote account password, etc.
You may specify any number of extra variables at the end of the command in the format foo=12 bar=34 instead of the more verbose default --extra-vars="foo=12 bar=34".

Examples

The following command to run the provision playbook on the production inventory host with the --user and --private-key command line flags:

ansible-playbook deploy/ansible/provision.yml --inventory=deploy/ansible/inventory/production --user=ubuntu --private-key=~/keyfile.pem

can be run like:

./deploy/run-playbook.sh provision production --user=ubuntu --private-key=~/keyfile.pem

And the following command to run the deploy playbook on the vagrant inventory host with the commit and local extra variables:

ansible-playbook deploy/ansible/deploy.yml --inventory=deploy/ansible/inventory/vagrant --extra-vars="commit=testing local=true"