Subspace

Subspace is a rubygem meant to make provisioning as easy as Capistrano makes deploying.

http://tvtropes.org/pmwiki/pmwiki.php/Main/SubspaceAnsible

It is powered by Ansible. Most of the roles require you to configure variables that the role uses.

Installation

First, install ansible (>2.0)

OSX:

brew install ansible

Linux:

apt-get install ansible

Add this line to your application's Gemfile:

gem 'subspace'

Or install it yourself as:

$ gem install subspace

Mitogen

Optionally, you can install a python/pip packaged called "Mitogen" which dramatically speeds up running ansible over ssh. See Here for details.

pip install mitogen

Subspace will try and detect if mitogen is present and use it can. If mitogen causes problems (sometimes it can cause problems depending on the system versions, and particaularly when brand new versions of anible come up and it hasn't updated), you can disable it:

DISABLE_MITOGEN=1 subspace provision env

Usage

`subspace init`

Initialize the project for subspace. Creates config/subspace with all necessary files.

Subspace 3 supports terraform. You will need to create an IAM user manually with administrative access to the target AWS environment for terraform.

`subspace bootstrap <environment>`

Ensures the $HOME/.ssh directory is present and ensures python is installed. Python is required to be installed on the remote server for the provision command to work.

`subspace provision <environment>`

Runs the playbook at config/provision/<environment.yml>.

You can pass certain options through to the ansible-playbook command. See the provision command for the current list.

At the time of this writing, we pass through the ansible-playbook "tags" and "start-at-task" options. The tags option is probably the most useful.

e.g. To run only the alienvault tasks (all of which have been tagged with the 'alienvault' tag): subspace provision staging --tags=alienvault

`subspace maintain <environment>`

Runs the playbook at config/provision/<environment.yml> but only the tasks tagged with "maintenance".

You can pass certain options through to the ansible-playbook command. See the maintain command for the current list.

At the time of this writing, we pass through the ansible-playbook "limit" option.

e.g. To run only on the host "prod-web1": subspace maintain production --limit=prod-web1

`subspace maintenance_mode <environment> --on`

This sets up nginx to return all requests as 503 and serve only the static page at /u/apps/{{project_name}}/current/public/maintenance.html which must be checked into your project and deployed to the server.

--on and --off, defaults to off.

Only works for hosts using the nginx role, but you can pass in your entire environment. Running it on worker servers won't hurt anything.

MUST be turned off manually by running subspace maintenance_mode <environment> --off, even a deploy will not disable maintenance mode.

Tagged roles

Role	Tags	Comment
alienvault	alienvault	All tasks in the alienvault role have been tagged 'alienvault'
common	upgrade	runs apt-get update and apt-get upgrade
common	authorized_keys	updates the authorized_keys file for the deploy user
rails	appyml
monit	monit	All tasks in the monit role have been tagged 'monit'

`subspace secrets <environment> [--edit] [--create]`

The secrets command will manage encrypted secrets for different environments. The default action is simply to show the secrets defined for an environment. Pass --edit to edit them in the system editor (vim, etc).

This uses ansible-vault under the hood and requires a vault password file. You will need to get the .vault_pass from from a teammate out of band (secrets.10fw.ne, 1password, sticky-note, etc), and put it into config/provision/.vault_pass

These secrets are used during provisioning to populate variables in a few different places:

config/application.yml, which uses the figaro gem to manage environment variables in rails.
config/database.yml, which handles the database connection password.

Subspace uses a template file in config/provision/templates/application.yml.template that contains environment variables for all environments. If you have non-secret variables that change based on the target server, you can simply put that in plaintext in the template file. This was designed so the configuration that is not secret is visible and version controlled, while the secret values are stored in the vault files for their environments.

NOTE: application.yml should be in the .gitignore, since subspace creates a new version on the server and symlinks it on top of whatever is checked in. You should make changes to the template file instead, which should be checked in to version control.

The default template created by subspace init looks like this:

# These environment variables are applied to all environments, and can be secret or not

# This is secret and can be changed on all three environment easily by using subspace vars <env> --edit
SECRET_KEY_BASE: {{secret_key_base}}

# This is not secret, and is the same value for all environments
ENABLE_SOME_FEATURE: false

development:
  INSECURE_VARIABLE: "this isn't secret"

staging:
  INSECURE_VARIABLE: "but it changes"

production:
  INSECURE_VARIABLE: "on different servers"

You can also use this command to automatically create a local version of config/application.yml based on the template and encrypted secrets for a specific environment.

# Create a local copy of config/application.yml with the secrets encrypted in secrets/development.yml
$ subspace vars development --create

This can get you up and running quickly in development securely.

Procedure for updating on projects

When subspace is updated, you should also update it for projects that use it. If subspace is locked to a specific version in the a project's gemfile, you'll need to update that to the new release number, first. Make sure this won't introduce any breaking changes by looking at the changelog.

bundle update subspace

Then,

subspace provision production

If you get an error saying you need a vault password file, you need to get it from somoene on the team (see above). You might also need to update ansible.

You'll want to do this for each environment (ie: subspace provision qa, etc.). Best to start with staging and work your way up.

Host configuration

We need to know some info about hosts, but not much. See the files for details, it's mostly the hostname and the user that can administer the system, eg ubuntu on AWS/ubuntu, ec2-user, or even root (not recommended, but used on linode/Digital Ocean)

Role Configuration

This is a description of all the roles that are included by installing subspace, along with their configuration.

common

This role should almost always be there. It ties a bunch of stuff together, runs apt-get update or yum upgrade, sets hostnames, and generally makes the server sane.

project_name: my_project
swap_space: 512M
deploy_user: deploy

Note: we grant the deploy user limited sudo access to run service xyz restart and also add it to the adm group so it can view logs in /var/log.

Roles

This is a description of all the roles that are included by installing subspace, along with their configuration.

alienvault

Fixes CVEs on remote servers by installing updated versions of packages depending on the operating system version.

Each CVE fix is tagged by the CVE name so updates can be targeted to a specific vulnerability.

Variables: None

apache

The most important file for an apache install is the "project.conf" file that gets created in sites-available and symlinked to sites-enabled. This is generated in a sensible way, but if you want to customize it you can do so by setting this variable to anything other than "project.conf":

apache_project_conf: my_custom_configuration.conf

Then place my_custom_configuration.conf in config/provision/templates/my_custom_configuration.conf. This will still get copied to the server as sites-available/{project_name}.conf

Apache also support canonicalizing the domain now, so if you alwyas want to redirect to WWW for example, simply add a variable:

canonical_domain: "www.example.com"

collectd

Collectd is a super useful daemon that grabs and reports statistics about a server's health. Adding this role will make your server start reporting to a graphite server that you specify, and you can make cool graphs and data feeds after that using something like Grafana

graphite_host: graphite.example.com
graphite_port: "2003"

Aside from basic statistics like free memory, disk, load averages, etc, we have some custom things:

If Postgres and delayed job are installed, it will collect stats on number of outstanding delayed jobs. a. If you have pg on a different server or in RDS, you can set this manually:

collectd_pgdj: true
If apache is installed, it will collect stats from the /server-status page
If nginx is installed, it will collect stats from the "status port"
(TODO) add something for pumas
(TODO) add something for sidekiq
If you're using our standard lograge format, you can enable lograge collection which will provide stats on request count and timers (db/view/total)

rails_lograge: true

common

delayed_job

Install monitoring and automatic startup for delayed job workers via monit. You MUST set the job_queues variable as follows:

job_queues:
  - default
  - mailers
  - exports

If you want to have multiple workers for a single queue, just add the queue name multiple times:

job_queues:
  - default
  - mailers
  - exports
  - exports
  - exports

Please note that by default, delayed job does not set a queue (eg it uses the "null" queue). You MUST also add an initializer to your rails app where you set the default queue name to "default" (or some other queue). Otherwise, the named queue workers managed by this role will not process the "null" queue.

# config/initializers/delayed_job.rb
Delayed::Worker.default_queue_name = 'default'

Defaults:

delayed_job_command: bin/delayed_job

letsencrypt

This creates a single certificate for every server alias/server name in the configuration file.

letsencrypt_email: "me@example.com"
server_name: app.example.com

If you'd like more control over the cert, you can customize the variable le_ssl_cert as follows:

le_ssl_cert:
  cert_name: "{{server_name}}"
  preferred_challenges: "http"
  plugin: standalone
  domains: "{{ [server_name] + server_aliases }}"

For example, to force a manual DNS challenge you can do the following:

le_ssl_cert:
  cert_name: star_example
  preferred_challenges: dns
  plugin: manual
  domains:
    - example.com
    - "*.example.com"

(you will need to futz around the first time and manually install the DNS record, but it should work on renewals)

Note that this role needs to be included before the webserver (apache or nginx) role

logrotate

Installs logrotate and lets you configure logs for automatic rotation. Example config for rails:

logrotate_scripts:
  - name: rails
    path: "/u/apps/{{project_name}}/shared/log/{{rails_env}}.log"
    options:
      - weekly
      - size 100M
      - missingok
      - compress
      - delaycompress
      - copytruncate

memcache

Installs memcache on the server. By default, memcache will only listen on localhost which needs to be changed if other servers needs to connect.

# Default Value
memcache_bind: "127.0.0.1"

# bind to all interfaces
memcache_bind: "0.0.0.0"

newrelic-infra

This role will install the next-gen "Newrelic One" infrastructure agent which can perform a few different functions for newrelic. The previous "newrelic" role is deprecated.

Variables:

# Required, the newrelic license key you get after signing up.
newrelic_license: "longhashthingyougetfromnewrelichere"
# Optional - send logs to newrelic one's log aggregator.
newrelic_logs:
  - name: rails-production
    path: /u/apps/blah/shared/log/production.log
  - name: nginx-error
    path: /var/log/nginx/error.log

nginx-rails

Configures nginx to look at localhost:9292 for the socket/backend connection. If you need to do fancy stuff you should simply override this role

subspace override nginx-rails

defaults are here, we'll probably add more:

client_max_body_size: 4G
ssl_force_redirect: true
default_server: true
keepalive_timeout: 10
extra_nginx_config: ""

Optional variables:

asset_cors_allow_origin: Set this to set the Access-Control-Allow-Origin for
everything in /assets.

nginx_proxy_read_timeout: Set [proxy_read_timeout](https://nginx.org/en/docs/http/ngx_http_proxy_module.html#proxy_read_timeout). This is in seconds. You probably only want to change this if using rack-timeout (although I may be wrong). If using rack-timeout, it should be slightly higher than the rack-timeout timeout. I'm doing 5 seconds higher, but that was arbitrarily chosen.

ssl_force_redirect: redirect all HTTP traffic to HTTPS on the same host.  Defaults to true and only applies if ssl_enabled is also true.
extra_nginx_config: anything else you want to configure in the main nginx config block, formatted like:
extra_nginx_config: |
  proxy_http_version 1.1;
  chunked_transfer_encoding off;
  proxy_buffering off;
  proxy_cache off;

nodejs

Used to install different versions of NodeJS. This uses NodeSource's apt repositories. You must define a variable called nodejs_version and choose a major version supported by NodeSource:

nodejs_version: 14.x
nodejs_version: 17.x
nodejs_version: lts
nodejs_version: current

The full list of distributions is here: https://github.com/nodesource/distributions#installation-instructions

papertrail

passenger

postgresql

Sets up a postgres server - only use this on the database machine.

backups_enabled: true
s3_db_backup_bucket: disabled
s3_db_backup_prefix: "{{project_name}}/{{rails_env}}"
database_user: "{{project_name}}"

puma

Use the puma app server for your rails app. Usually combined with nginx to server as a static file server and reverse proxy.

Prerequesites:

add gem puma to your gemfile
add config/puma/ to the linked_dirs config in capistrano's deploy.rb

This role will generate a reasonable puma.rb and configure it to be controlled by systemd.

Variables:

puma_workers: 1        # Puma process count (usually == vCPU count)
puma_min_threads: 4    # Min threads/process
puma_max_threads: 16   # Max threads/process

rails

Provisions for a rails app. This one is probably pretty important.

We no longer provider default values, so make sure to define all the following variables:

rails_env: production
database_pool: 5
database_name: "{{project_name}}_{{rails_env}}"
database_user: "{{project_name}}"
database_host: localhost
database_adapter: postgresql
database_password: # usually defined in the encrypted vault
job_queues:
  - default
  - mailers

redis

Installs redis on the server.

# Change to * if you want this available everywhere instead of localhost
redis_bind: 127.0.0.1

As of Subspace 3.0, this uses the official redis apt repo instead of the debian/ubuntu ones. If you previously had installed redis from the distro, you will need to manually uninstall, purge, and reinstall. This should not delete any data but back it up just in case.

sudo apt-get purge redis-server
sudo apt-get install redis-server

resque

Install monitoring and automatic startup for resque workers via monit. You MUST set the job_queues variable as follows:

job_queues:
  - default
  - mailers
  - exports

redis_bind: "*"

ruby-common

Installs ruby on the machine. YOu can set a version by picking off the download url and sha hash from ruby-lang.org

ruby_version: ruby-2.4.1
ruby_checksum: a330e10d5cb5e53b3a0078326c5731888bb55e32c4abfeb27d9e7f8e5d000250
ruby_download_location: 'https://cache.ruby-lang.org/pub/ruby/2.4/ruby-2.4.1.tar.gz'
bundler_version: 2.0.1

sidekiq

This will install a monit script that keeps sidekiq running. We spawn one sidekiq instance that manages as many queues as you need. Varaibles of note:

# Process these queues on this server
job_queues:
  - default
  - mailers

# Number of sidekiq *processes* to run
sidekiq_workers: 1

Note that as of v0.4.13, we now also add a unique job queue for each host with its hostname. This is handy if you need to assign a job to a specific host. In general you should use named queues, but occasionally this is useful and there's no harm in having it there unused.

Sidekiq uses redis by default, and rails connects to a redis running on localhost by default. However, this role does not depend on redis since in production it's likely redis will be running elsewhere. If you're provisioning a standalone server, make sure to include the redis role.

Other Internal Roles

Since ansible doesn't support versioning of roles, we cloned the role here so that it doesn't change unexpectedly. We expect to update from upstream occasionally, please let us know if we're missing something we should have.

You should not include these roles directly in your subspace config files. For example, instead of including zenoamaro.postgresql, simply include our postgresql role which depens on zenoamaro's role.

Thanks to the following repositories for making their roles available:

Mitogen

In order to dramatically speed up ansible, you can install Mitogen: https://github.com/mitogen-hq/mitogen/blob/master/docs/ansible_detailed.rst

pip install -g mitogen

Subspace will automatically detect this and update your ansible.cfg file so it is blazing fast.

Directory Structure

ansible/roles

Contains all of our custom roles. When the gem is installed and subspace init is ran, the newly created ansible.cfg will be configured to look for these roles.

template

Contains the template files that get copied over when subspace init is ran.

Development

After checking out the repo, run bin/setup to install dependencies. Then, run rake spec to run the tests. You can also run bin/console for an interactive prompt that will allow you to experiment.

To install this gem onto your local machine, run bundle exec rake install. To release a new version:

update the version number in version.rb
gem build subspace.gemspec
gem push subspace-x.y.z.gem

This will create a git tag for the version, push git commits and tags, and push the .gem file to rubygems.org.

Contributing

Bug reports and pull requests are welcome on GitHub at https://github.com/tenforwardconsulting/subspace. This project is intended to be a safe, welcoming space for collaboration, and contributors are expected to adhere to the Contributor Covenant code of conduct.