Trouble developing Rails plugins/gems with generators

rubyonrails-core
1

Hi,

I've been trying to develop a Rails gem/plugin with generators for Rails 3. I first had a separate gem project with a gem statement in my Gemfile with a :path option to point at it. But then I had to run $ rake install on each change in my gem to have Rails pick up on it. I have now instead put my generators inside RAILS_ROOT/lib so they are easier to test/develop.

lib/generators - ability      ability_generator.rb - clear - config

When I run $ rails g ... AuthAssist:   auth_assist:ability   auth_assist:clear   auth_assist:config

$ rails g auth_assist:ability Could not find generator auth_assist:ability.

What am I doing wrong here? Must the generators be in a gem/plugin to be picked up by Rails? What is the best/easiest approach for developing plugins/generators with Rails 3?

Thanks!

2

Hi,

I’ve been trying to develop a Rails gem/plugin with generators for

Rails 3. I first had a separate gem project with a gem statement in my

Gemfile with a :path option to point at it. But then I had to run $

rake install on each change in my gem to have Rails pick up on it. I

have now instead put my generators inside RAILS_ROOT/lib so they are

easier to test/develop.

lib/generators

  • ability

    ability_generator.rb

  • clear

  • config

When I run $ rails g

…

AuthAssist:

auth_assist:ability

auth_assist:clear

auth_assist:config

$ rails g auth_assist:ability

Could not find generator auth_assist:ability.

What am I doing wrong here? Must the generators be in a gem/plugin to

be picked up by Rails?

What is the best/easiest approach for developing plugins/generators

with Rails 3?

Thanks!

This might help… http://github.com/indirect/rails3-generators

I have not really looked into generators recently but I am guessing not much has changed.

Anuj

3

I worked it out myself. It had to do with the fact that the generators for some reason require the namespace to match a containing folder, much like the Java package mechanism.

lib/generators - auth_asisst    - ability      ability_generator.rb

# ability_generator.rb module AuthAssist   module Generators     class AbilityGenerator < Rails::Generators::Base ...

A bit akward IMO, that a generator can be picked up as available but then can't be found when attempting to run it. Would be nice with a better error message such as "can't find x:y in generators/x/y_generator.rb as expected."

4

I worked it out myself. It had to do with the fact that the generators

for some reason require the namespace to match a containing folder,

much like the Java package mechanism.

lib/generators

  • auth_asisst

    • ability

      ability_generator.rb

ability_generator.rb

module AuthAssist

module Generators

class AbilityGenerator < Rails::Generators::Base

…

A bit akward IMO, that a generator can be picked up as available but

then can’t be found when attempting to run it.

Would be nice with a better error message such as "can’t find x:y in

generators/x/y_generator.rb as expected."

Yeah, I have felt the need for a proper error message otherwise you can’t really tell what is going on. I will add a Lighthouse ticket for the same.

Anuj

5

On another note:

I would like to have available the methods used in Rails 3 templates. I see many generators including Rails::Generators::Migration and using the method migration_template to create a new migration. What I would like is for my generator to create the options for running a basic migration command, say: $ rails g migration add_user_name_to_user user_name:string

But to be run from inside my migration. I tried the following

migration 'add_user_name_to_user user_name:string'

But the migration method is not available by default and I can't seem to find it anywhere... any idea how to do this? I could hack it using "run" which works, but produces:

run rails g migration add_admin_field_to_user admin:boolean from "."

Which just doesn't feel right :wink:

Thanks!

6

On another note:

I would like to have available the methods used in Rails 3 templates.

I see many generators including Rails::Generators::Migration and using

the method migration_template to create a new migration.

What I would like is for my generator to create the options for

running a basic migration command, say:

$ rails g migration add_user_name_to_user user_name:string

But to be run from inside my migration. I tried the following

migration ‘add_user_name_to_user user_name:string’

But the migration method is not available by default and I can’t seem

to find it anywhere… any idea how to do this?

I could hack it using “run” which works, but produces:

run rails g migration add_admin_field_to_user admin:boolean from “.”

Which just doesn’t feel right :wink:

Thanks!

Just have a look at rails3-generators in github. It has got generators for datamapper, haml and so on. I am sure you can find clues there.

7

On a further note. I can't seem to get any .rb files in RAILS_ROOT/lib to load when I start my rails server.

Say I have a file

# lib/auth_assistant.rb puts "Hello from AuthAssist"

8

On a further note. I can’t seem to get any .rb files in RAILS_ROOT/lib

to load when I start my rails server.

Say I have a file

lib/auth_assistant.rb

puts “Hello from AuthAssist”

–

In the old days of Rails 2.3+ you would put a require statement in

application.rb, but I think in Rails 3 all files in lib should be

loaded by default!?

How do I configure my lib files to be loaded in Rails 3?

I think you still need to require it in the application.rb file. I might be wrong as I have not been following the Rails-core development as much so don’t take my word for it.

Anuj

9

It turned out I had to include the require statement in an initializer. Putting it in the application.rb didn't work (not found error). I has to due with the load order I'm sure. Thanks for the help :slight_smile: