my_zipcode_gem migration generators not working - ruby-on-rails

Question

I'm pretty sure that the problem is due to the fact that this gem looks to be 3-4 years old and rails has changed how we do migrations. But I'm not too familiar with gems/generators. I'm trying to follow the instructions to do the instructions listed here.
rails g my_zipcode_gem:models
rake db:migrate
rake zipcodes:update
However, when I do the first step I end up getting this:
/Users/thammond/.rvm/gems/ruby-2.1.1/gems/my_zipcode_gem-0.1.3/lib/generators/my_zipcode_gem/models_generator.rb:35:in `create_migration': wrong number of arguments (3 for 0) (ArgumentError)
from /Users/thammond/.rvm/gems/ruby-2.1.1/gems/railties-4.1.0/lib/rails/generators/migration.rb:63:in `migration_template'
from /Users/thammond/.rvm/gems/ruby-2.1.1/gems/my_zipcode_gem-0.1.3/lib/generators/my_zipcode_gem/models_generator.rb:36:in `create_migration'
from /Users/thammond/.rvm/gems/ruby-2.1.1/gems/thor-0.19.1/lib/thor/command.rb:27:in `run'
from /Users/thammond/.rvm/gems/ruby-2.1.1/gems/thor-0.19.1/lib/thor/invocation.rb:126:in `invoke_command'
from /Users/thammond/.rvm/gems/ruby-2.1.1/gems/thor-0.19.1/lib/thor/invocation.rb:133:in `block in invoke_all'
from /Users/thammond/.rvm/gems/ruby-2.1.1/gems/thor-0.19.1/lib/thor/invocation.rb:133:in `each'
from /Users/thammond/.rvm/gems/ruby-2.1.1/gems/thor-0.19.1/lib/thor/invocation.rb:133:in `map'
from /Users/thammond/.rvm/gems/ruby-2.1.1/gems/thor-0.19.1/lib/thor/invocation.rb:133:in `invoke_all'
from /Users/thammond/.rvm/gems/ruby-2.1.1/gems/thor-0.19.1/lib/thor/group.rb:232:in `dispatch'
from /Users/thammond/.rvm/gems/ruby-2.1.1/gems/thor-0.19.1/lib/thor/base.rb:440:in `start'
from /Users/thammond/.rvm/gems/ruby-2.1.1/gems/railties-4.1.0/lib/rails/generators.rb:157:in `invoke'
from /Users/thammond/.rvm/gems/ruby-2.1.1/gems/railties-4.1.0/lib/rails/commands/generate.rb:11:in `<top (required)>'
from /Users/thammond/.rvm/gems/ruby-2.1.1/gems/activesupport-4.1.0/lib/active_support/dependencies.rb:247:in `require'
from /Users/thammond/.rvm/gems/ruby-2.1.1/gems/activesupport-4.1.0/lib/active_support/dependencies.rb:247:in `block in require'
from /Users/thammond/.rvm/gems/ruby-2.1.1/gems/activesupport-4.1.0/lib/active_support/dependencies.rb:232:in `load_dependency'
from /Users/thammond/.rvm/gems/ruby-2.1.1/gems/activesupport-4.1.0/lib/active_support/dependencies.rb:247:in `require'
from /Users/thammond/.rvm/gems/ruby-2.1.1/gems/railties-4.1.0/lib/rails/commands/commands_tasks.rb:135:in `generate_or_destroy'
from /Users/thammond/.rvm/gems/ruby-2.1.1/gems/railties-4.1.0/lib/rails/commands/commands_tasks.rb:51:in `generate'
from /Users/thammond/.rvm/gems/ruby-2.1.1/gems/railties-4.1.0/lib/rails/commands/commands_tasks.rb:40:in `run_command!'
from /Users/thammond/.rvm/gems/ruby-2.1.1/gems/railties-4.1.0/lib/rails/commands.rb:17:in `<top (required)>'
from bin/rails:4:in `require'
from bin/rails:4:in `<main>'
Any idea what I need to do to get that gem working? It provides exactly what I'm looking for in my app.
Thanks!
Edit: Adding the generation code:
module MyZipcodeGem
class ModelsGenerator < Base
include Rails::Generators::Migration
source_root File.expand_path('../templates', __FILE__)
def initialize(*args, &block)
super
end
def generate_models
# puts ">>> generate_zipcodes:"
end
def add_gems
add_gem "mocha", :group => :test
end
def create_models
template 'zipcode_model.rb', "app/models/zipcode.rb"
template 'county_model.rb', "app/models/county.rb"
template 'state_model.rb', "app/models/state.rb"
end
# Implement the required interface for Rails::Generators::Migration.
# taken from http://github.com/rails/rails/blob/master/activerecord/lib/generators/active_record.rb
def self.next_migration_number(dirname)
if ActiveRecord::Base.timestamped_migrations
Time.now.utc.strftime("%Y%m%d%H%M%S")
else
"%.3d" % (current_migration_number(dirname) + 1)
end
end
def create_migration
migration_template 'migration.rb', "db/migrate/create_my_zipcode_gem_models.rb"
end
def create_rakefile
template 'zipcodes.rake', "lib/tasks/zipcodes.rake"
end
end
end
# /Users/cblackburn/.rvm/gems/ruby-1.9.2-p136/gems/activerecord-3.0.3/lib/rails/generators/active_record/

Answer 1

It looks like it is calling the migration using parameters that are no longer expected. You have two options:
1) fork the code, update it to use rails 4 conventions, and create a pull request on github. Assuming the owner is still active they will bring your code into the master and republish the gem. You would have help support the community and feel good about it in the process. There are plenty on here like myself who can help you with this.
2) Find another gem to do what you want, such as http://www.rubygeocoder.com/ which I've used several times and is awesome at doing location/zipcode problems