Generates a list of params straight from the database schema

generate_params.rb

#!/usr/bin/env ruby
# Usage: generate_params.rb [/path/to/db/schema.rb] [table name]
# By: Kirk Elifson <kirk [at] parodybit [dot] net>

def print_usage
  puts "", "\tUsage: ruby generate_params.rb /path/to/db/schema.rb table_name", ""
  exit
end

print_usage if ARGV.length != 2

full_path  = ARGV.shift
table_name = ARGV.shift

begin
  schema = File.open(full_path, 'r')
rescue Errno::ENOENT => e
  puts "Failure to open file '#{full_path}'"
  puts "Please provide the full path to schema.rb (e.g., /path/to/myblog/db/schema.rb)"
  print_usage
end

begin
  schema_content = schema.read
  table_start    = schema_content.index("create_table \"#{table_name}\"")
  table_end      = schema_content[table_start..-1].index("end") - 3 # Remove end line
  lines          = schema_content[table_start..(table_start + table_end)].split("\n").map(&:strip)
  lines.shift # Remove create_table line
rescue => e
  puts "Not a valid table name."
  exit
end

columns = []
lines.each do |line|
  next if line.include?("\"created_at\"") || line.include?("\"updated_at\"") # Timestamps are not params
  line.gsub(/t.[a-z]+[\s]+"([a-zA-Z0-9_-]+)"/) {
    columns << Regexp.last_match[1]
  }
end
columns.sort.each { |column| puts ":#{column}" }