1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
|
Rails Application Templates
===========================
Application templates are simple Ruby files containing DSL for adding gems/initializers etc. to your freshly created Rails project or an existing Rails project.
After reading this guide, you will know:
* How to use templates to generate/customize Rails applications.
* How to write your own reusable application templates using the Rails template API.
--------------------------------------------------------------------------------
Usage
-----
To apply a template, you need to provide the Rails generator with the location of the template you wish to apply using the -m option. This can either be a path to a file or a URL.
```bash
$ rails new blog -m ~/template.rb
$ rails new blog -m http://example.com/template.rb
```
You can use the rake task `rails:template` to apply templates to an existing Rails application. The location of the template needs to be passed in to an environment variable named LOCATION. Again, this can either be path to a file or a URL.
```bash
$ rake rails:template LOCATION=~/template.rb
$ rake rails:template LOCATION=http://example.com/template.rb
```
Template API
------------
The Rails templates API is easy to understand. Here's an example of a typical Rails template:
```ruby
# template.rb
generate(:scaffold, "person name:string")
route "root to: 'people#index'"
rake("db:migrate")
git :init
git add: "."
git commit: %Q{ -m 'Initial commit' }
```
The following sections outline the primary methods provided by the API:
### gem(*args)
Adds a `gem` entry for the supplied gem to the generated application’s `Gemfile`.
For example, if your application depends on the gems `bj` and `nokogiri`:
```ruby
gem "bj"
gem "nokogiri"
```
Please note that this will NOT install the gems for you and you will have to run `bundle install` to do that.
```bash
bundle install
```
### gem_group(*names, &block)
Wraps gem entries inside a group.
For example, if you want to load `rspec-rails` only in the `development` and `test` groups:
```ruby
gem_group :development, :test do
gem "rspec-rails"
end
```
### add_source(source, options = {})
Adds the given source to the generated application's `Gemfile`.
For example, if you need to source a gem from "http://code.whytheluckystiff.net":
```ruby
add_source "http://code.whytheluckystiff.net"
```
### environment/application(data=nil, options={}, &block)
Adds a line inside the `Application` class for `config/application.rb`.
If `options[:env]` is specified, the line is appended to the corresponding file in `config/environments`.
```ruby
environment 'config.action_mailer.default_url_options = {host: 'http://yourwebsite.example.com'}, env: 'production'
```
A block can be used in place of the `data` argument.
### vendor/lib/file/initializer(filename, data = nil, &block)
Adds an initializer to the generated application’s `config/initializers` directory.
Let's say you like using `Object#not_nil?` and `Object#not_blank?`:
```ruby
initializer 'bloatlol.rb', <<-CODE
class Object
def not_nil?
!nil?
end
def not_blank?
!blank?
end
end
CODE
```
Similarly, `lib()` creates a file in the `lib/` directory and `vendor()` creates a file in the `vendor/` directory.
There is even `file()`, which accepts a relative path from `Rails.root` and creates all the directories/files needed:
```ruby
file 'app/components/foo.rb', <<-CODE
class Foo
end
CODE
```
That’ll create the `app/components` directory and put `foo.rb` in there.
### rakefile(filename, data = nil, &block)
Creates a new rake file under `lib/tasks` with the supplied tasks:
```ruby
rakefile("bootstrap.rake") do
<<-TASK
namespace :boot do
task :strap do
puts "i like boots!"
end
end
TASK
end
```
The above creates `lib/tasks/bootstrap.rake` with a `boot:strap` rake task.
### generate(what, *args)
Runs the supplied rails generator with given arguments.
```ruby
generate(:scaffold, "person", "name:string", "address:text", "age:number")
```
### run(command)
Executes an arbitrary command. Just like the backticks. Let's say you want to remove the `README.rdoc` file:
```ruby
run "rm README.rdoc"
```
### rake(command, options = {})
Runs the supplied rake tasks in the Rails application. Let's say you want to migrate the database:
```ruby
rake "db:migrate"
```
You can also run rake tasks with a different Rails environment:
```ruby
rake "db:migrate", env: 'production'
```
### route(routing_code)
Adds a routing entry to the `config/routes.rb` file. In the steps above, we generated a person scaffold and also removed `README.rdoc`. Now, to make `PeopleController#index` the default page for the application:
```ruby
route "root to: 'person#index'"
```
### inside(dir)
Enables you to run a command from the given directory. For example, if you have a copy of edge rails that you wish to symlink from your new apps, you can do this:
```ruby
inside('vendor') do
run "ln -s ~/commit-rails/rails rails"
end
```
### ask(question)
`ask()` gives you a chance to get some feedback from the user and use it in your templates. Let's say you want your user to name the new shiny library you’re adding:
```ruby
lib_name = ask("What do you want to call the shiny library ?")
lib_name << ".rb" unless lib_name.index(".rb")
lib lib_name, <<-CODE
class Shiny
end
CODE
```
### yes?(question) or no?(question)
These methods let you ask questions from templates and decide the flow based on the user’s answer. Let's say you want to freeze rails only if the user wants to:
```ruby
rake("rails:freeze:gems") if yes?("Freeze rails gems?")
# no?(question) acts just the opposite.
```
### git(:command)
Rails templates let you run any git command:
```ruby
git :init
git add: "."
git commit: "-a -m 'Initial commit'"
```
|
