CAP DB DUMP

Capistrano recipes for backing your production database and transferring it to your local machine.

1. Install the gem in bundler’s Gemfile:

gem 'cap_db_dump'

$ bundle install

1. Require the gem in the cap file:

require 'cap_db_dump/recipes'

Finally, add the :db_dump => true flag on the server where you’d like the mysqldump to run:

task :staging do
  role :web,                  'example.com'
  role :app,                  'example.com'
  role :db,                   'example.com', :primary => true, :db_dump => true
end

Make sure rails_env and database_engine variables are set

set :rails_env, "production"
set :database_engine, :mysql # specify :mysql | :psql

You also might want to add these to your .gitignore:

“‘ current.sql.gz dump_.sql.gz “`

Create a dump:

cap database:dump

Create a dump, and transfer it with scp:

cap database:dump_and_transfer

Only dump the schema for a given set of tables (don’t dump the data):

set :schema_only_tables, [:sessions, :my_large_table]

With postgres this uses pg_dump –exclude-table-data, so the tables are still created on restore, just empty.

The database settings are read from config/database.yml in the current release. If that file uses ERB (for example, to pull credentials out of Rails.application.credentials), it can’t be read as plain YAML. In that case the settings are fetched from Rails on the server instead, with:

cd <current_path> && RAILS_ENV=<rails_env> bundle exec rails runner "..."

This boots your app on the db_dump server, so it needs Rails 6.1+ and the credentials key to be present there.

Control this with :database_config_source:

set :database_config_source, :auto  # default. plain YAML, unless database.yml contains <%
set :database_config_source, :yaml  # always read database.yml as plain YAML (the old behavior)
set :database_config_source, :rails # always ask rails runner for the resolved config

Restore script is not included, but you may want to do something like this (postgres example):

#!/usr/bin/env bash

set -x

createdb my_app_development

set -e

gunzip -c current.sql.gz -k | pg_restore --verbose --clean --no-acl --no-owner -h localhost -d my_app_development

Conor Hunt (conorh)
Stephen Schor (nodanaonlyzuul)

Copyright © 2008-2022 Scott Taylor / Eastmedia <scott@eastmedia.com>

Released under the MIT + GPL licenses