Alexander Shmatko Alexander Shmatko - 6 months ago 20
Ruby Question

How to fetch schema version using regex?

I have the following text:

# encoding: UTF-8
# This file is auto-generated from the current state of the database. Instead
# of editing this file, please use the migrations feature of Active Record to
# incrementally modify your database, and then regenerate this schema definition.
#
# Note that this schema.rb definition is the authoritative source for your
# database schema. If you need to create the application database on another
# system, you should be using db:schema:load, not running all the migrations
# from scratch. The latter is a flawed and unsustainable approach (the more migrations
# you'll amass, the slower it'll run and the greater likelihood for issues).
#
# It's strongly recommended that you check this file into your version control system.

ActiveRecord::Schema.define(version: 20160405090205) do

# These are extensions that must be enabled in order to support this database
enable_extension "plpgsql"


I need to get 20160405090205 number. How can I get it?

I've tried
/version.*[0-9]/
, but this captures only version: 20160405090205.

Answer
schema = File.read(Rails.root.join('db', 'schema.rb'))
version, *_ = schema.match(/version: (\d+)/).captures
version # => "20160405090205"

version, *_ = ... is needed here because captures returns an array even when there is a simple capture.