■作业要求
Ruby 1.8.7 -> Ruby 1.9.3
Rails 2.3.16 -> Rails 3.2.13
■服务器环境
mysql5.5
■升级过程
1.请理解以下内容
Rails3 Beta版重点导览(http://ihower.tw/blog/archives/3653)
Rails3 RC版重点导览(http://ihower.tw/blog/archives/4590)
Rails 3.1 RC版重点导览(http://ihower.tw/blog/archives/5611)
环境设定与Bundler(http://ihower.tw/rails3/environments-and-bundler.html)
Routing 路由(http://ihower.tw/rails3/routing.html)
Assets与Ajax(http://ihower.tw/rails3/assets-and-ajax.html)
2.安装ruby1.9、rails3环境，新建rails3工程，将rails2代码放到rails3工程中。
这一步主要保证rails2代码放到rails3环境中可以正常启动，怎样能正常启动呢？
①确保rails本身框架级代码修改正确(新增config/application.rb、变更config/routes.rb等)
使用rails_upgrade升级插件(https://github.com/rails/rails_upgrade)可以比较轻松完成这一步.
rails_upgrade命令：
rake rails:upgrade:check命令会找出rails2->rails3.0所有需要升级的代码及修改方法
rake rails:upgrade:routes命令会产生rails3用route文件(config/routes.rb)
rake rails:upgrade:configuration命令产生rails3用config文件(config/application.rb)
rake rails:upgrade:gems命令产生rails3用gem管理文件(Gemfile)
rails_upgrade运行结果例
# rake rails:upgrade:check
/////rake rails:upgrade:check结果开始/////
Old router API
The router API has totally changed.
More information: http://yehudakatz.com/2009/12/26/the-rails-3-router-rack-it-up/
The culprits:
- config/routes.rb
New file needed: config/application.rb
You need to add a config/application.rb.
More information: http://omgbloglol.com/post/353978923/the-path-to-rails-3-approaching-the-upgrade
The culprits:
- config/application.rb
named_scope is now just scope
The named_scope method has been renamed to just scope.
More information: http://github.com/rails/rails/commit/d60bb0a9e4be2ac0a9de9a69041a4ddc2e0cc914
The culprits:
- app/models/xxx1.rb
- app/models/xxx2.rb
... ...
/////rake rails:upgrade:check结果结束/////
# rake rails:upgrade:routes
/////rake rails:upgrade:routes结果开始/////
xxx::Application.routes.draw do
match '' => 'default#index'
match 'xxx1' => 'default#login', :id => 'xxx1'
match 'xxx2' => 'default#login', :id => 'xxx2'
match '/:controller(/:action(/:id))'
match ':controller/:action/:id/:id2' => '#index'
match ':controller/:action/:id/:id2/:id3' => '#index'
end
/////rake rails:upgrade:routes结果结束/////
# rake rails:upgrade:configuration
/////rake rails:upgrade:configuration结果开始/////
# Put this in config/application.rb
require File.expand_path('../boot', __FILE__)
require 'rails/all'
Bundler.require(:default, Rails.env) if defined?(Bundler)
module Xxxx
class Application < Rails::Application
config.autoload_paths += [config.root.join('lib')]
config.encoding = 'utf-8'
# Settings in config/environments/* take precedence over those specified here.
# Application configuration should go into files in config/initializers
# -- all .rb files in that directory are automatically loaded.
# Add additional load paths for your own custom dirs
# config.load_paths += %W( #{RAILS_ROOT}/extras )
# Specify gems that this application depends on and have them installed with rake gems:install
# config.gem "bj"
# config.gem "hpricot", :version => '0.6', :source => "http://code.whytheluckystiff.net"
# config.gem "sqlite3-ruby", :lib => "sqlite3"
# config.gem "aws-s3", :lib => "aws/s3"
config.gem "rmagick", :version => '1.15.12', :lib => 'RMagick'
config.gem "rspec-rails", :lib => false
# Only load the plugins named here, in the order given (default is alphabetical).
# :all can be used as a placeholder for all plugins not explicitly named
# config.plugins = [ :exception_notification, :ssl_requirement, :all ]
# Skip frameworks you're not going to use. To use Rails without a database,
# you must remove the Active Record framework.
# config.frameworks -= [ :active_record, :active_resource, :action_mailer ]
# Activate observers that should always be running
# config.active_record.observers = :cacher, :garbage_collector, :forum_observer
# Set Time.zone default to the specified zone and make Active Record auto-convert to this zone.
# Run "rake -D time" for a list of tasks for finding time zone names.
#config.time_zone = 'Beijing'
config.active_record.default_timezone = 'Beijing'
# The default locale is :en and all translations from config/locales/*.rb,yml are auto loaded.
# config.i18n.load_path += Dir[Rails.root.join('my', 'locales', '*.{rb,yml}')]
config.i18n.default_locale = 'zh'
config.action_controller.session = {
:session_key => '_xxxx_session',
:secret => 'fcfa0df9da9faia9fd9as8fd9as8f98as9fa9idffifa9unjvrqryq87d787b8v78xm8qfu7e8357q46q57x78erz2le89rub7q8758q7ecbr8cwe7rq8ear8ebr7x87',
:secure => true
}
config.action_controller.session_store = :active_record_store
end
end
/////rake rails:upgrade:configuration结果结束/////
# rake rails:upgrade:gems
/////rake rails:upgrade:gems结果开始/////
# Edit this Gemfile to bundle your application's dependencies.
# This preamble is the current preamble for Rails 3 apps; edit as needed.
source 'http://rubygems.org'
gem 'rails', '3.0.6'
gem 'rmagick', '1.15.12', :require => 'RMagick'
gem 'rspec-rails'
/////rake rails:upgrade:gems结果结束/////
②确保rails2中使用的plugin、在rails3中有替代方案.
常用的Plugin在这里都能找到对应的升级版本。(http://rubygems.orghttp://railsplugins.org、)
例:
rails2
/vendor/plugins/will_paginate
rails3
http://rubygems.org/gems/will_paginate
Gemfile
gem "will_paginate", "~> 3.0.4"
3.运行rails3工程,查找语法问题
■Ruby 1.8.7 -> Ruby 1.9.3带来的修改点
1)所有含有英文以外字符的.rb文件，第一行追加
# -*- encoding : utf-8 -*-
例：
Ruby 1.8
class Site < ActiveRecord::Base
#ruby1.8不需要加magic comment
end
Ruby 1.9
# -*- encoding : utf-8 -*-
class Site < ActiveRecord::Base
#ruby1.9需要加magic comment
end
2)NKF被废弃
例：
Ruby 1.8
NKF.nkf("-s", string)
Ruby 1.9
string.to_s.encode("sjis", "utf-8")
3)ruby1.9中，使用toutf8等字符转换的方法需要require 'kconv'
例：
Ruby 1.8
site_id = "string".toutf8
Ruby 1.9
require 'kconv'
site_id = "string".toutf8
详细：https://github.com/johnnyhalife/waz-storage/issues/8
4)prec_f被废弃
例：
Ruby 1.8
1.prec_f
Ruby 1.9
1.to_f
5)Struct.members.include?方法变更
例：
Ruby 1.8
struct = Struct.new(:id,:name)
struct.members.include?("id")
Ruby 1.9
struct = Struct.new(:id,:name)
struct.members.include?(:id)
6)Object#tap方法变更
class Campaign < ActiveRecord::Base
has_many: ads
attr_accessor :tap #属性恰巧叫tap
end
class Ad < ActiveRecord::Base
belongs_to: campaign
end
Ruby 1.8、rails2
ad = Ad.first
ad.campaign可以正常返回campaign对象
Ruby 1.9、rails3
ad = Ad.first
ad.campaign返回nil,无法正常返回campaign对象
修改方法：
attr_accessor :tap 改变量名
7)String#to_a方法被废弃
例：
Ruby 1.8
"string".to_a
Ruby 1.9
"string".split
8)字符串和数组相加结果变更
ids = [1]
str = ""
str += "id = '#{ids}'"
例：
Ruby 1.8结果
id = '1'
Ruby 1.9结果
id = '[1]'
■Rails 2.3.16 -> Rails 3.2.13带来的修改点
▼config、railties相关
9)RAILS_ENV -> Rails.env
RAILS_ROOT -> Rails.root
10)filter_parameter_logging方法废弃
rails2
filter_parameter_logging :password
rails3
config/application.rb中加入
config.filter_parameters += [:password]
11)rails3中time_zone_aware_attributes默认开启
rails2
time_zone_aware_attributes默认关闭
解决方法：
config/application.rb中加入
config.active_record.time_zone_aware_attributes = false
如果updated_at、created_at以外的datetime类型字段向插入本地时间，请按解决方法修改。
12)uninitialized constant ActiveRecord::RecordNotFound (NameError) (可能非共通)
rails s启动时，如果出现该错误，在environment.rb添加类定义
require File.expand_path('../application', __FILE__)
module ActiveRecord
class RecordNotFound < ActiveRecordError
end
end
▼controller相关
13)verify方法废弃，作为gem使用
解决方法：
①Gemfile中添加
gem "verification", "~> 1.0.1"
②我的项目不适用方法①,从gem verification的github取得verification.rb,作为共通方法放到lib/action_controller/verification.rb下
14)error处理
①rails3中clean_backtrace方法废弃
②rails3中rescue_action_locally方法废弃
③rails3中rescue_action不会被自动调用
问题①②③的解决方法在下边例子中给出了。
例：
rails2
rescue_from ActionController::RoutingError,
ActionController::UnknownAction,
ActiveRecord::RecordNotFound do
render :partial => '/default/notfound', :layout => true, :status => 404
end
def rescue_action(exception)
if RAILS_ENV == "development"
logger.error(clean_backtrace(exception))
rescue_action_locally(exception)
return
end
case exception
when ActionController::RoutingError, ActionController::UnknownAction, ActiveRecord::RecordNotFound
render :partial => '/default/notfound', :layout => false, :status => 404
else
begin
UserMailer.deliver_email_xxx(
exception,
clean_backtrace(exception),
session.instance_variable_get("@data"),
params,
request.env)
logger.error(exception.message)
logger.error(clean_backtrace(exception))
rescue => e
logger.error(e)
end
render :partial => 'error'
end
end
rails3
rescue_from Exception do |exception|
rescue_action(exception)
end
def rescue_action(exception)
new_wapper = ActionDispatch::ExceptionWrapper.new(Rails.env, exception)
if Rails.env == "development"
logger.error(new_wapper.full_trace)
raise new_wapper
end
case exception
when ActiveRecord::RecordNotFound
render :partial => '/default/notfound', :layout => false, :status => 404
else
begin
UserMailer.email_xxx(
exception,
new_wapper.full_trace,
session.instance_variable_get("@data"),
params,
request.env).deliver
logger.error(exception.message)
logger.error(new_wapper.full_trace)
rescue => e
logger.error(e)
end
render :partial => 'error'
end
end
④rescue_from处理方式修改后，发生ActionController::RoutingError、ActionController::UnknownAction异常时，
无法迁移到/default/notfound页面
原因：
rails2: RoutingError、ActionNotFound(UnknownAction)错误发生时，被作为异常抛出
rails3: 由于全面导入Rack的关系，现在的Route其实也是一个Rack middleware。所以上边2个错误不再被当作异常抛出(控制台中可以看到错误信息)
解决方法：
config/application.rb
config.exceptions_app = self.routes
routes.rb
match "/404", :to => "application#not_found"
application_controller.rb
def not_found
render :partial => '/default/notfound', :layout => false, :status => 404
end
参考资料：
http://blog.plataformatec.com.br/2012/01/my-five-favorite-hidden-features-in-rails-3-2/
▼model相关
15)find -> where
例：
rails2
self.find(:first, :conditions => ["site_id = ? ", site_id])
self.all(:conditions => ["site_id =? ", site_id], :joins => [:ad], :group => :ad_id)
rails3
self.where(["campaign_id = ? ", campaign_id]).first
self.joins( [:ad]).wherel(["site_id =? ", site_id]).group =>(:ad_id)
16)named_scope -> scope
例：
rails2
named_scope :not_delete, :conditions => ["status <> 'delete'"]
rails3
scope :not_delete, :conditions => ["status <> 'delete'"]
17)validate写法变更
例：
rails2
validates_presence_of :name
validates_presence_of :succeed_allow_site_id, :if => Proc.new{|site| site.is_succeed_allow_site == '1' }, :message => "必须输入"
def validate
errors.add(:base, "message")
end
def validate_on_create
errors.add(:base, "message")
end
def before_save
self.begin_date = nil if self.check_date_set = "0"
end
rails3
validates :name presence=true
validates :succeed_allow_site_id,:presence =>{ :if => Proc.new{|site| site.is_succeed_allow_site == '1' }, :message => "必须输入"}
validate do
errors.add(:base, "message")
end
validate(:on => :create) do
errors.add(:base, "message")
end
before_save do |site|
self.begin_date = nil if self.check_date_set = "0"
end
18)errors#on方法变更
errors#on方法在rails3中仍然存在，但意义不同了
rails2
errors.on(:height)
rails3
errors[:height].first
19)errors#invalid?方法废弃
rails2
errors.invalid?(:height)
rails3
errors.added?(:height)
20)save_without_validation!写法变更
例：
rails2
site.name = "name"
site.save(false)
site.name = "name"
site.save_without_validation!
rails3
site.name = "name"
site.save(:validate => false)
site.name = "name"
site.save!(:validate => false)
21)set_table_name -> table_name
例：
rails2
class BigSite < ActiveRecord::Base
self.set_table_name = sites
end
rails3
class BigSite < ActiveRecord::Base
self.table_name = sites
end
22)通过select选项起别名后，rails2和rails3结果不同
背景：
sites表中id字段为int型
rails2
record_id = Site.first(:select => "id as record_id").record_id
rails3
record_id = Site.select("id as record_id").first.record_id
rails2中record_id为字符串类型,rails3中record_id为int型
23)has_many :through 删除机制改变
背景：
creative.rb
has_many :creative_elements, :through => :creative_element_relations
creative_element.rb
has_one :creative_element_relation, :dependent => :delete
在执行 creative.creative_elements.destroy_all 的时候
rails2行为
1.删除creative_elements数据
2.creative_element.rb中dependent语句删除creative_element_relation
rails3行为
1.删除creative_element_relations数据
解决方法：
creative_element_relation.rb
+ belongs_to :creative_element, :dependent => :delete
creative_element.rb
- has_one :creative_element_relation, :dependent => :delete
▼views相关
24)<% form_for %> -> <%= form_for %>
Rails2
<% form_for :site, :url=>{:action => 'site_create'} do |f| %>
Rails3
<%= form_for :site, :url=>{:action => 'site_create'} do |f| %>
25)rails3默认加h
rails2中用h过滤的，rails3中去掉h
Rails2
<%=h site.name %>
Rails3
<%= site.name %>
rails2中想输出html代码的，rails3中加raw
Rails2
<%= "<tr>" if true %>
Rails3
<%=raw "<tr>" if true %>
26)disable_with行为变更
<%= submit_tag '追加', :name => 'add' , :disable_with => "追加"%>
解析后代码
Rails2
if (window.hiddenCommit) {
window.hiddenCommit.setAttribute('value', this.value);
}else {
hiddenCommit = document.createElement('input');
hiddenCommit.type = 'hidden';
hiddenCommit.value = this.value;
hiddenCommit.name = this.name;
this.form.appendChild(hiddenCommit);
}
this.setAttribute('originalValue', this.value);
this.disabled = true;
this.value='追加';
result = (this.form.onsubmit ? (this.form.onsubmit() ? this.form.submit() : false) : this.form.submit());
if (result == false) {
this.value = this.getAttribute('originalValue');this.disabled = false;
}
return result;
Rails3
function disableFormElements(form) {
form.select('input[type=submit][data-disable-with]').each(function(input) {
input.store('rails:original-value', input.getValue());
input.setValue(input.readAttribute('data-disable-with')).disable();
});
}
说明：
rails2会新建隐藏域，controller中params[:add]可以取到值
rails3是将disable_with的submit按钮全变为不可用
解决方法：
将rails2解析后代码放到:onclick中。
<%= submit_tag '追加', :name => 'back' , :onclick => "if (window.hiddenCommit) { window.hiddenCommit.setAttribute('value', this.value); }else { hiddenCommit = document.createElement('input');hiddenCommit.type = 'hidden';hiddenCommit.value = this.value;hiddenCommit.name = this.name;this.form.appendChild(hiddenCommit); }this.setAttribute('originalValue', this.value);this.disabled = true;this.value='追加';result = (this.form.onsubmit ? (this.form.onsubmit() ? this.form.submit() : false) : this.form.submit());if (result == false) { this.value = this.getAttribute('originalValue');this.disabled = false; }return result;" %>
27)link_to的remote,confirm方法失效(非共通)
背景：rails2时，使用集成在rails框架中的prototype完成link_to的remote,confirm功能。
rails3时，推荐使用jquery gem(也能完成link_to的remote,confirm功能), prototype从rails框架中移出，做成了prototype gem。
问题出现在我对上述背景不了解的时候，没有在Gemfile中引入prototype。
解决方法：
①rails2时，我的项目既使用了prototype(Hash、escapeHtml等)又使用了jquery(画面项目控制)，
如果你的项目和我一样，对prototype依赖比较大，可以在Gemfile中引入prototype。
gem "prototype-rails", "3.2.1"
解决confirm后，删除动作token验证问题
在页面中添加代码 <%= csrf_meta_tags %>
例：
<%= javascript_include_tag 'xxx' %>
<%= csrf_meta_tags %>
如果你的项目不想使用assets功能，请将gem "prototype-rails", "3.2.1" 命令生成的
C:\Ruby193\lib\ruby\gems\1.9.1\gems\prototype-rails-3.2.1\vendor\assets\javascripts\
controls.js、dragdrop.js、effects.js、prototype_ujs.js、prototype.js
放到public/javascript下
并在页面中引入prototype、prototype_ujs
<%= javascript_include_tag 'prototype' %>
<%= javascript_include_tag 'prototype_ujs' %>
②如果你的项目对prototype没有依赖，推荐使用jquery-rails
gem "jquery-rails", "x.x.x" (请参照rails new demo 命令生成的Gemfile)
28)IE8 jquery 日期控件显示位置不正(非共通)
popup弹出位置通过jquery的width()、height()来计算。
popup弹出位置不正是由prototype升级带来的。
rails2内嵌的prototype版本为1.6.0.3、gem "prototype-rails", "3.2.1"升级后prototype版本随之升级为1.7
prototype升级对jquery的width()、height()方法产生影响。
解决方法：
重写jquery的_checkOffset方法。
①将下边代码放到项目共同js中。
/* == rewrite _checkOffset method ==*/
function calDatePickerOffset(){
$j.extend($j.datepicker,{
_checkOffset: function(inst, offset, isFixed) {
var dpWidth = inst.dpDiv.outerWidth();
var dpHeight = inst.dpDiv.outerHeight();
var inputWidth = inst.input ? inst.input.outerWidth() : 0;
var inputHeight = inst.input ? inst.input.outerHeight() : 0;
if ($j.browser.msie) {
var viewWidth = document.documentElement.clientWidth + ( isFixed ? 0 : ((document.documentElement && document.documentElement.scrollLeft) || document.body.scrollLeft));
} else {
var viewWidth = document.documentElement.clientWidth + ( isFixed ? 0 : $j(document).scrollLeft());
}
if ($j.browser.msie) {
var viewHeight = document.documentElement.clientHeight + ( isFixed ? 0 : ((document.documentElement && document.documentElement.scrollTop) || document.body.scrollTop));
} else {
var viewHeight = document.documentElement.clientHeight + ( isFixed ? 0 : $j(document).scrollTop());
}
offset.left -= (this._get(inst, 'isRTL') ? (dpWidth - inputWidth) : 0);
offset.left -= (isFixed && offset.left == inst.input.offset().left) ? $j(document).scrollLeft() : 0;
offset.top -= (isFixed && offset.top == (inst.input.offset().top + inputHeight)) ? $j(document).scrollTop() : 0;
// now check if datepicker is showing outside window viewport - move to a better place if so.
offset.left -= Math.min(offset.left, (offset.left + dpWidth > viewWidth && viewWidth > dpWidth) ? Math.abs(offset.left + dpWidth - viewWidth) : 0);
offset.top -= Math.min(offset.top, (offset.top + dpHeight > viewHeight && viewHeight > dpHeight) ? Math.abs(dpHeight + inputHeight) : 0);
return offset;
}
});
}
②在有日期控件的页面中调用calDatePickerOffset方法
29)link_to、redirect_to(url_for)方法变更(不清楚是否共通)
现象：
当点击有多个参数的link后，没有参数的link也被添加了不想添加的参数。
例：
test.html.erb
link_to 'link_name', :action => 'action_name'
link_to 'link_name_multi_id', :action => 'action_name1', :id => 'first_id', :id2 => 'sec_id'
初始化进入该页面时，产生如下url
/action_name
/action_name1/first_id/sec_id
当点击action_name1链接后，再回到该页面,产生如下url
/action_name/first_id/sec_id
/action_name1/first_id/sec_id
解决方法：
link_to 'link_name', :action => 'action_name', :id => nil, :id2 => nil
PS:
这个问题不清楚是不是共通问题，有可能和我项目的route方式有关，如果你的项目没有这个问题，请无视。
30)number_to_currency负数输出格式变更
<%= number_to_currency(-1000000, :precision => 2, :unit => '￥'%>
rails2结果
-\ 100,000.00
rails3结果
- 100,000.00
解决方法：
<%= number_to_currency(-1000000, :precision => 2, :unit => '￥', :negative_format => "%u-%n") %>
▼plugin、gems相关
31)mysql -> mysql2
rails3推荐使用mysql2
database.yml
rails2
adapter: mysql
rails3
adapter: mysql2
32)i18n
rails3要求ruby1.9下的i18n,我这里是i18n(0.6.1)
使用
https://github.com/svenfuchs/rails-i18n/blob/master/rails/locale
中相应的xx.yml替换
config/locales/xx.yml
33)will_paginate
①:prev_label -> :previous_label
②array.paginate发生异常
解决方法
environment.rb添加下边内容
require 'will_paginate/array'
③修改当前页字体
div.pagination .current{ font-style:normal; }
34)rmagic
取得filesize写法变更
rails2
require 'RMagick'
def size(file_path)
if !file_path.blank?
img_list = Magick::ImageList.new(file_path)
img_list = img_list.coalesce
return img_list.filesize
end
rails3
require 'RMagick'
def size(file_path)
if !file_path.blank?
img_list = File.open(file_path)
return File.size(img_list)
end
end
35)不必再使用ez_where(rails3 where可以实现)
rails2
conditions = Caboose::EZ::Condition.new
conditions << ["status = ?", params[:status]]
conditions << ["id = ?", params[:id]] unless params[:id].blank?
rails3
conditions = model.where("status = ?", params[:status])
conditions = conditions.where("id = ?", params[:id]) unless params[:id].blank?
36)rspec
rspec (1.3.0) -> rspec (2.13.0)修改过程
①
Ⅰ.生成新的spec_helper.rb文件
工程目录下执行 rails g rspec:install
Ⅱ.删除lib/tasks/rspec.rake文件
Ⅲ.
修改代码
ⅰ
文件头添加
# -*- encoding : utf-8 -*-
ⅱ
@logger = Logger.new("#{RAILS_ROOT}/log/test.log")
↓
@@logger = Logger.new("#{::Rails.root}/log/test.log")
ⅲ
self.fixture_path = RAILS_ROOT + '/spec/fixtures/access_tag/add/'
↓
self.fixture_path = "#{::Rails.root}" + '/spec/fixtures/access_tag/add/'
②
执行单个文件
rspec -cfs spec/models/access_tag/add_spec.rb
执行所有文件
rake spec
执行所有模型
rake spec:models
③
执行单个测试时没有问题，整体执行时，部分test_case执行不能通过。
原因：
各个test_case之间没有清空数据。
修改方法：
spec/spec_helper.rb
config.use_transactional_fixtures = true
↓
config.use_transactional_fixtures = false
▼其他
37)rails3产品模式log,每次提交中间没有空行
/usr/local/ruby-1.9.3-p429/lib/ruby/gems/1.9.1/gems/railties-3.2.13/lib/rails/rack/logger.rb
def call_app(request, env)
# Put some space between requests in development logs.
if Rails.env.development?
Rails.logger.info ''
Rails.logger.info ''
end
解决方法：
将if Rails.env.development?去掉
38)incompatible character encodings: UTF-8 and ASCII-8BIT (非共通)
背景：
sites表的name字段是tinyblob类型
页面执行到<%=site.name%>时，出错。
具体原因:
http://yehudakatz.com/2010/05/05/ruby-1-9-encodings-a-primer-and-the-solution-for-rails/
解决方法：
<%=site.name.force_encoding("UTF-8")%>
39)password_field字段无法保留值。
原因及修改方法：
password_field renders with nil value by default
This makes the use of passwords secure by default if you want to render
the value of the password_field you have to do for instance
f.password_field(:password, :value => @user.password)
https://github.com/rails/rails/commit/1851af84c1c7244dc416be9c93a4700b70e801e3