fb comment

http://developers.facebook.com/docs/reference/plugins/comments

Unique ID 填了反而不行用 是怎樣 = =

rails 設定多個 smtp account 寄信

Using multiple SMTP accounts with Rails & ActionMailer

可利用此技巧, 達到多SMTP 寄信的目的
<br />#action_mailer.yml<br />production:<br /> website1:<br /> domain: "gary@superfriends.com"<br /> user_name: gary<br /> password: superduper<br /> address: smtp.gmail.com<br /> port: 587<br /> authentication: :plain<br /><br /> website2:<br /> domain: mysupercooldomain.com<br /> user_name: ABCDEF<br /> password: blahblah<br /> address: mail.authsmtp.com<br /> port: 25<br /> authentication: :plain<br /><br /><br />#app/models/mailer1.rb<br />class Website1 < ActionMailer::Base<br /> def load_settings<br /> options = YAML.load_file("#{RAILS_ROOT}/config/action_mailer.yml")[RAILS_ENV]["website1"]<br /> @@smtp_settings = {<br /> :address => options["address"],<br /> :port => options["port"],<br /> :domain => options["domain"],<br /> :authentication => options["authentication"],<br /> :user_name => options["user_name"],<br /> :password => options["password"]<br /> }<br /> end<br /><br /> def welcome_email(recipient, sent_at = Time.now)<br /> load_settings<br /> @subject = 'Thank you for visiting website 1'<br /> @recipients = RAILS_ENV == "production" ? recipient : "cavneb@gmail.com"<br /> @from = 'gary@superfriends.com'<br /> @sent_on = sent_at<br /> end<br />end<br /><br /><br /><br /><br />

haproxy nginx passenger munin

step1: nginx need stub_status_module
compile with [--with-http_stub_status_module]

step2: install munin
sudo apt-get install munin munin-node

 
#/etc/munin/munin.conf
#This will tell munin to connect to munin-node at 127.0.0.1 on the same machine.
[foo.net]
    address 127.0.0.1
    use_node_name yes


#Edit the file /etc/munin/munin-node.conf and change # Which port to bind to set
host 127.0.0.1

#Make sure that this is present in the file

allow ^127\.0\.0\.1$

http://github.com/barttenbrinke/munin-plugins-rails
http://www.alfajango.com/blog/how-to-monitor-your-railspassenger-app-with-munin/
http://github.com/jnstq/munin-nginx-ubuntu

 
#haproxy setting
reqisetbe       ^Host:\ munin.foo.net        foomunin

#nginx config
server {
   listen 6166; 
   server_name munin.foo.net;
   root /home/foo/deploy/shared/directory/munin;   
}


#/etc/munin/plugin-conf.d/munin-node
[foo_*]
env.log_file '/home/foo/app/production.log'
user foo
command /opt/ruby-enterprise-1.8.7-2010.02/bin/ruby %c
env.graph_category Foo

rails ip 辨識國家

how-to-know-user-location-with-rails
github geoip
Super fast IP to lat/lng in Rails

下載點 http://geolite.maxmind.com/download/geoip/database/

<br />IP_COUNTRY = GeoIP.new("#{Rails.root}/public/GeoIP.dat")<br /><br />IP_COUNTRY.country(request.remote_ip)<br />

haproxy rails ip

haproxy不能正確記錄客戶端的IP
關於 rails 的扔remote_ip
http://kkito.cn/index.php/blog/getArticle/102/rails%E4%B8%AD%E5%BA%94%E6%B3%A8%E6%84%8F%E5%8F%AF%E8%83%BD%E5%AE%A2%E6%88%B7%E7%AB%AFip%E5%9C%B0%E5%9D%80%E6%98%AF%E4%BC%AA%E8%A3%85%E7%9A%84

capistrano path rake fail

http://blog.zerobearing.com/2009/04/27/capistrano-rake-command-not-found/
http://stackoverflow.com/questions/588934/using-ruby-enterprise-edition-gems-are-not-installed-where-i-would-expect
http://forum.slicehost.com/comments.php?DiscussionID=3657
http://stackoverflow.com/questions/257616/sudo-changes-path-why
http://groups.google.com/group/emm-ruby/browse_thread/thread/d0c685bbd096823a#msg_effa7d6ad42c541c
http://www.f15ijp.com/2009/11/30/sudo-no-tty-present-and-no-askpass-program-specified/

/etc/ssh/sshd_config:

PermitUserEnvironment yes
/etc/init.d/sshd restart


~/.ssh/environment
PATH=/opt/ruby-enterprise-1.8.7-2010.02/bin:/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin:/usr/games


http://formatinternet.wordpress.com/2009/07/06/sudo-rake-command-not-found/
~/.bashrc
alias sudo='sudo env PATH=$PATH'


sudo ln -s `which rake` /usr/local/bin/

#sudo: no tty present and no askpass program specified error
the /etc/sudoers file.
#commend sudo visudo
Defaults visiblepw

delayed_job capistrano production fail

主要參考
http://railscasts.com/episodes/171-delayed-job
http://www.magnionlabs.com/2009/2/28/background-job-processing-in-rails-with-delayed_job

不知道哪邊弄錯了用capistrano deploy 想啟動delayed_job 卻好像都沒反應
後來終於看到 有script/delayed_job run的指令 這個動作才可以讓你看到你錯在哪, start 只會無聲無息
<br />set :env, 'production' #不知道為範例的rails_env 都抓不到值<br /><br />namespace :delayed_job do<br /> desc "Start delayed_job process" <br /> task :start, :roles => :app do<br /> run "cd #{current_path}; ruby script/delayed_job start -- #{env}" <br /> end<br /><br /> desc "Stop delayed_job process" <br /> task :stop, :roles => :app do<br /> run "cd #{current_path}; script/delayed_job stop -- #{env}" <br /> end<br /><br /> desc "Restart delayed_job process"<br /> task :restart, :roles => :app do<br /> run "cd #{current_path}; script/delayed_job restart -- #{env}" <br /> end<br />end<br /><br />

rmagic cannot open shared object file: No such file or directory

libMagickCore.so.* cannot open shared object file: No such file or directory

http://github.com/jnstq/rails-nginx-passenger-ubuntu

To get rid of this error i executed

ldconfig /usr/local/lib

nginx passenger config

nginx, worker_processes, and passenger_max_pool_size
Production Rails Tuning with Passenger: PassengerMaxProcesses

 
worker_processes 4;    <= Setting the number of Nginx workers to the number of CPU cores should be sufficient. 

http { 
passenger_max_pool_size 20; # memory 256M should be 2,  2G should be 30, max_pool 不要設太大, 不要讓它吃到swap,  free -ml ;  vmstat 2  都可以看到現在memory 的情況
passenger_max_instances_per_app 15; #每種ap 能用到最多的instance, 所以如果跑兩個app 就會再少一點

# PassengerPoolIdleTime
# Recommended to be avg time per page * 2
# In Google Analytics... (Avg time on site / Avg page views) * 2
# Default: 300
passenger_pool_idle_time 144

 } 

超小型web server 設定
How to save MUCH RAM when running rails (linode/slicehost) and mod_rails passenger

改變預設的cache 目錄

http://railsforum.com/viewtopic.php?id=11033

<br />#光只是改變Rails 設定是不夠的<br />config.action_controller.page_cache_directory = RAILS_ROOT + '/public/cache/'<br /><br />#還需要更改web server 的設定, 以下是apache 的設定<br />RewriteEngine On<br />RewriteCond %{THE_REQUEST} ^(GET|HEAD)<br />RewriteCond %{REQUEST_URI} ^([^.]+)/?$<br />RewriteCond %{DOCUMENT_ROOT}/cache/%1.html -f<br />RewriteRule ^[^.]+/?$ /cache/%1.html [QSA,L]<br /><br />RewriteCond %{THE_REQUEST} ^(GET|HEAD)<br />RewriteCond %{DOCUMENT_ROOT}/cache/index.html -f<br />RewriteRule ^$ /cache/index.html [QSA,L]<br />

[Ptt][心得] Restful下遇到params[:id]含有.的解法

在restful的前提下, 遇到class的to_param是字串, 而剛好某筆
紀錄的to_param欄位含有.

一般情形下會發生錯誤, 因為restful會把.後的東西當成format
這時的解法, 變成要在routes.rb中的xxx.resources加上參數

ex:
<br /> map.resources :categories, :requirements => {:id => /.*/}<br />

paramter change permanently, header status

<br /> if params[:id] != @episode.to_param<br /> headers["Status"] = "301 Moved Permanently"<br /> redirect_to episode_url(@episode)<br /> else<br /> @comment = Comment.new(:episode => @episode)<br /> respond_to do |format|<br /> format.html<br /> format.rss<br /> end<br /> end<br />

Practical Rails Social Networking Site memo (2)

<br />#Ch10<br />module ApplicationHelper<br /> def yes_no(bool)<br /> ...<br /> end<br /> def tag_cloud(tags, classes)<br /> max, min = 0, 0<br /> tags.each do |tag|<br /> max = tag.count if tag.count > max<br /> min = tag.count if tag.count < min<br /> end<br /> divisor = ((max - min) / classes.size) + 1<br /> tags.each do |tag|<br /> yield tag.name, classes[(tag.count - min) / divisor]<br /> end<br /> end<br />end<br /><br /><% tag_cloud @tags, %w(tag1 tag2 tag3 tag4 tag5) do |name, css_class| %><br /><%= link_to name, tag_path(name), :class => css_class %><br /><% end %><br /><br /><br /><br />

Practical Rails Social Networking Site memo

<br />#Ch2<br />def to_param<br />"#{id}-#{permalink}"<br />end<br /><br />def show<br />@page = Page.find(params[:id].to_i)<br />end<br /><br />#Some database servers (including MySQL) will automatically do this conversion for you. However,PostgreSQL and some others do not, so it is a good idea to add this to your controllers. You could also overridean ActiveRecord method<br /><br /><br /><br />#Ch3<br />module LoginSystem<br /> protected<br /> def is_logged_in?<br /> @logged_in_user = User.find(session[:user]) if session[:user]<br /> end<br /><br /> def logged_in_user<br /> return @logged_in_user if is_logged_in?<br /> end<br /><br /> def logged_in_user=(user)<br /> if !user.nil?<br /> session[:user] = user.id<br /> @logged_in_user = user<br /> end<br /> end<br /><br /> def self.included(base)<br /> base.send :helper_method, :is_logged_in?, :logged_in_user<br /> end<br />end<br /><br /><br />map.show_user '/user/:username',:controller => 'users',:action => 'show_by_username'<br />map.resources :users, :member => { :enable => :put }<br /><br /><br /><ul><%= render :partial => 'role', :collection => @user.roles %></ul><br /><h2>Roles available:</h2><br /><ul><%= render :partial => 'role', :collection => (@all_roles - @user.roles) %></ul><br /><br /><br />#Ch4<br />def self.up<br /> create_table :categories do |t|<br /> t.column :name, :string<br /> end<br /> news_category = Category.create(:name => 'Site News')<br /> change_column :articles, :category_id, :integer, :default => news_category<br />end<br /><br />def self.down<br /> change_column :articles, :category_id, :integer, :default => 0<br /> drop_table :categories<br />end<br /><br />def get_http_auth_data<br /> username, password = nil, nil<br /> auth_headers = ['X-HTTP_AUTHORIZATION', 'Authorization', 'HTTP_AUTHORIZATION',<br /> 'REDIRECT_REDIRECT_X_http_AUTHORIZATION']<br /> auth_header = auth_headers.detect { |key| request.env[key] }<br /> auth_data = request.env[auth_header].to_s.split<br /><br /> if auth_data && auth_data[0] == 'Basic'<br /> username, password = Base64.decode64(auth_data[1]).split(':')[0..1]<br /> end<br /> return [username, password]<br />end<br /><br />@request.env['HTTP_ACCEPT'] = 'application/xml'<br />@request.env['Authorization'] = 'Basic ' + Base64::b64encode('editor:12345')<br />

check timezone valid

<br />module TimeFunc<br /> def self.included(base)<br /> base.class_eval do<br /> base.extend Methods<br /> end <br /> end <br /> <br /> module Methods<br /> def check_timezone_legal(timezone)<br /> raise IllegalTimeZone unless ActiveSupport::TimeZone::ZONES.map(&:name).include?(timezone)<br /> end<br /> end<br />end<br />

migration

<br /><br />#add_OOXX_to_foos 可以直接指定foos table 作為操作的talbe<br />ruby script/generate migration add_express_token_to_orders express_token:string express_payer_id:string<br />

rjs page

page['foo']['style']
# => $('foo').style;
page['foo']['style']['color']
# => $('blank_slate').style.color;
page['foo']['style']['color'] = 'red'
# => $('blank_slate').style.color = 'red';
page['foo']['style'].color = 'red'
# => $('blank_slate').style.color = 'red';

respond_to jsonp

respond_to recognizes • JSON.
render :json => @person.to_json automatically sets the content type and takes a :callback option to specify a client-side function to call using the rendered JSON as an argument. #4185 [Scott Raymond, eventualbuddha]

<br /># application/json response<br /># with body 'Element.show({:name: "David"})'<br />respond_to do |format|<br /> format.json {<br /> render :json => { :name => "David" }.to_json,:callback => 'Element.show' <br /> }<br />end<br />

Bootstrap Initializer

Bootstrap Initializer
The files in config/initializers are loaded after Rails' environment is loaded (including environment.rb). However, there's a pre-environment
hook provided for you should you need to do things prior to Rails' environment getting in the mix: just create a config/preinitializer.rb file.

This file is loaded after the Rails classes are loaded but before the environment file and the environment configuration.

rescue_from Exception Handlers

rescue_from Exception Handlers
<br /> class PostsController < ApplicationController<br /> def rescue_action_in_public(exception)<br /> case(exception)<br /> when ActiveRecord::RecordNotFound<br /> render :file => '/bad_record'<br /> when NoMethodError<br /> render :file => '/no_method'<br /> else<br /> render :file => '/error'<br /> end<br /> end<br /> end<br /><br /><br />#======================================<br /> class PostsController < ApplicationController<br /> # Declare exception to handler methods<br /> rescue_from ActiveRecord::RecordNotFound, :with => :bad_record<br /> rescue_from NoMethodError, :with => :show_error<br /><br /> # Define handler methods<br /> def bad_record<br /> render :file => '/bad_record'<br /> end<br /><br /> def show_error(exception)<br /> render :text => exception.message<br /> end<br /> end<br /><br /><br />#======================================<br /> class PostsController < ApplicationController<br /> rescue_from(ActiveRecord::RecordNotFound) do |exception|<br /> render :file => '/bad_record'<br /> end<br /><br /> rescue_from NoMethodError, :with => proc do |e|<br /> render :text => e.message<br /> end<br /> end<br /><br />

Top 8 SQL Best Practices

Top 8 SQL Best Practices

1) Always use explicit joins. If I mean INNER JOIN, then I use INNER JOIN. No use of just plain "JOIN". Never, ever, ever use a comma join -- I consider that a mistake. If I explicitly state "CROSS JOIN" then I know I have consciously made that decision. Also, keep join conditions in an ON or USING clause; they should not go in the WHERE clause. I also put my join conditions in parentheses; for whatever reason, I find:
ON (foo=bar AND baz=bop) WHERE a=b
is easier to see that the join condition contains 2 conditions than
ON foo=bar AND baz=bop WHERE a=b

SQL Server TSQL Coding Conventions, Best Practices, and Programming Guidelines

SQL Server TSQL Coding Conventions, Best Practices, and Programming Guidelines

Try to avoid wildcard characters at the beginning of a word while searching using the LIKE keyword, as that results in an index scan, which defeats the purpose of an index. The following statement results in an index scan, while the second statement results in an index seek:

SELECT LocationID FROM Locations WHERE Specialities LIKE '%pples'
SELECT LocationID FROM Locations WHERE Specialities LIKE 'A%s'

Also avoid searching using not equals operators (<> and NOT) as they result in table and index scans.

---

Use 'Derived tables' wherever possible, as they perform better. Consider the following query to find the second highest salary from the Employees table:

SELECT MIN(Salary)
FROM Employees
WHERE EmpID IN
(
SELECT TOP 2 EmpID
FROM Employees
ORDER BY Salary Desc
)

The same query can be re-written using a derived table, as shown below, and it performs twice as fast as the above query:

SELECT MIN(Salary)
FROM
(
SELECT TOP 2 Salary
FROM Employees
ORDER BY Salary DESC
) AS A

This is just an example, and your results might differ in different scenarios depending on the database design, indexes, volume of data, etc. So, test all the possible ways a query could be written and go with the most efficient one.

---

While designing your database, design it keeping "performance" in mind. You can't really tune performance later, when your database is in production, as it involves rebuilding tables andindexes, re-writing queries, etc. Use the graphical execution plan in Query Analyzer or SHOWPLAN_TEXT or SHOWPLAN_ALL commands to analyze your queries. Make sure your queries do an "Index seek" instead of an "Index scan" or a "Table scan." A table scan or an index scan is a very bad thing and should be avoided where possible. Choose the right indexes on the right columns.

---

Use the more readable ANSI-Standard Join clauses instead of the old style joins. With ANSI joins, the WHERE clause is used only for filtering data. Where as with older style joins, the WHERE clause handles both the join condition and filtering data. The first of the following two queries shows the old style join, while the second one shows the new ANSI join syntax:

SELECT a.au_id, t.title
FROM titles t, authors a, titleauthor ta
WHERE
a.au_id = ta.au_id AND
ta.title_id = t.title_id AND
t.title LIKE '%Computer%'

SELECT a.au_id, t.title
FROM authors a
INNER JOIN
titleauthor ta
ON
a.au_id = ta.au_id
INNER JOIN
titles t
ON
ta.title_id = t.title_id
WHERE t.title LIKE '%Computer%'

rails performance memo

<br />#Use external programs<br /><br />def thumbnail(temp, target)<br /> system("/usr/local/bin/convert #{escape(temp)} -resize<br />48x48! #{escape(target}")<br />end<br /><br /><br />#Write inline C/C++ code<br />• RubyInline: Write foreign code within ruby code<br /> http://rubyinline.rubyforge.org/RubyInline/<br /><br />• Rice: Ruby Interface for C++ Extensions<br /> http://rice.rubyforge.org/<br /><br />• Ruby-FFI: a ruby extension for programmatically<br /> loading dynamic libraries<br /> http://github.com/ffi/ffi<br /><br />

That’s Not a Memory Leak, It’s Bloat; refactor

That’s Not a Memory Leak, It’s Bloat

<br />#:includes are Including Too Much<br />Article.find(:all, :include => [:user => [:posts => :comments]])<br /><br /><br />#:includes on a has_many<br />@articles.users.find(:all, :include => [:posts => :comments]])<br /><br /><br />#Use :select When You Must Instantiate Large Quantities of Records<br />@comment_ids = Comment.find(:all, :select => 'comments.id').collect{|comment| comment.id }<br /><br /><br />#Overfed Feeds<br />Check all the places you are making XML sandwiches. Often these controllers are written early on and don’t scale well. Maybe you have a sitemap XML feed that delivers every record under the sun to Google, or are rending some large amount of data for an API.<br /><br />

respond_to

<br /><br />#===============================================<br />class ApplicationController < ActionController::Base<br /> before_filter :adjust_format_for_iphone<br /> helper_method :iphone_user_agent?<br /><br />protected<br /> def adjust_format_for_iphone<br /> request.format = :iphone if iphone_user_agent? || iphone_subdomain?<br /> end<br /><br /> # Request from an iPhone or iPod touch?<br /> # (Mobile Safari user agent)<br /> def iphone_user_agent?<br /> request.env["HTTP_USER_AGENT" ] &&<br /> request.env["HTTP_USER_AGENT" ][/(Mobile\/.+Safari)/]<br /> end<br /><br /> def iphone_subdomain?<br /> return request.subdomains.first == "iphone"<br /> end<br />end<br /><br /><br /><br /># =======================<br /># custom format<br /># config/initializers/mime_types.rb<br />Mime::Type.register ‘audio/mpeg’, :mp3?Mime::Type.register ‘audio/mpegurl’, :m3u<br /><br /><br />def show<br /> @mp3 = Mp3.find(params[:id])<br /> respond_to do |format|<br /> format.html<br /> format.mp3 { redirect_to @mp3.url }<br /> format.m3u { render :text => @mp3.url }<br /> end<br />end<br /><br /><br /><br />#========================<br />def index<br /> @users = User.find(:all)<br /> respond_to do |format|<br /> format.js {<br /> render :update do |page|<br /> page.replace_html ‘content’, ‘<p>blah</p>’<br /> end<br /> }<br /> format.html #index.html.erb<br /> end<br />end<br /><br />

Restful memo

<br />#RESTful controller 一定是複數結尾<br />map.resources :events do |event|<br /> event.resource :map, :controller => ‘event_maps’<br />end<br /><br /><br />#=============================================<br /># 之前用的笨方法<br />map.resources :orders, :path_prefix => "/admin", :controller => "admin/orders"<br /><br /># 其實有namespace<br />map.namespace :admin do |admin|<br /> admin.resources :events<br />end<br /><br /># /app/controllers/admin/events_controller.rb<br />class Admin::EventsController < ApplicationController<br /> before_filter :require_admin<br /> def index<br /> ....<br /> end<br />end<br /><br /><br />#============================================<br />=begin <br />Considerations(1)<br /> a REST resource does not map directly to<br /> model. It’s high-level abstractions of what’s<br /> available through your web app.<br /> (Not always 1-to-1, maybe 1-to-many or 1-to-zero)<br /><br />• You don’t need to use all 7 actions if you don’t need them.<br /><br />Considerations(2)<br /><br />a RESTful controller may represent the<br />creation or delete of only a concept.<br />For example, a SpamsController create spam by changing a comment’s status<br />to spam without adding any records to the DB.<br /><br />Considerations(3)<br /> one resources should be associated with one controller.<br /> (well, you can use one controller handle more than one resources)<br />• offload privileged views into either a different controller or action.<br /><br />=end<br /><br /><br />#==================================<br /><br />#for event manager <br />map.resources :attendees <br /><br />class AttendeeController < ApplicationController<br /> before_filter :manager_required<br /> def show<br /> @person = @event.attendees.find(params[:id])<br /> end<br />end<br /><br />#for attendeeing user<br />map.resources :registers<br />class RegistersController < ApplicationController<br /> before_filter :login_required<br /><br /> def show<br /> @person = current_user.registers.find(params[:id])<br /> end<br />end<br /><br />1 attendee Model <br />2 Resources related <br />(2 Controller) <br /><br /><br />#==============================================<br /># http://ryandaigle.com/articles/2008/11/27/what-s-new-in-edge-rails-no-more-formatted-routes<br /># Old => New<br />formatted_article_path(article, :xml) => article_path(article, :format => :xml)<br />formatted_new_article_path(:json) => new_article_path(:format => :json)<br /># etc...<br /><br /><br />

Rails Best Practices

Rails Best Practices

<br />#Before<br /><% form_for @user do |f| %><br /> <%= f.text_field :email %><br /> <% for role in Role.all %><br /> <%= check_box_tag 'role_id[]', role.id, @user.roles.include?(role) %><br /> <%= role.name %><br /> <% end %><br /><% end %><br /><br />class User < ApplicationController<br /> def update<br /> @user = User.find(params[:id])<br /> if @user.update_attributes(params[:user])<br /> @user.roles.delete_all<br /> (params[:role_id] || []).each { |i| @user.roles << Role.find(i) }<br /> end<br /> end<br />end<br /><br /><br />#After<br /><% form_for @user do |f| %><br /> <% for role in Role.all %><br /> <%= check_box_tag 'user[role_ids][]', role.id, @user.roles.include?(role)<br /> <%= role.name %><br /> <% end %><br /> <%= hidden_field_tag 'user[role_ids][]', '' %><br /><% end %><br /><br />class User < ApplicationController<br /> def update<br /> @user = User.find(params[:id])<br /> @user.update_attributes(params[:user])<br /> # @user.role_ids = params[:user][:role_ids]<br /> end<br />end<br /><br /><br />#==========================================<br /><br />#Nested Model Forms (one-to-one) Before<br /><br />class Product < ActiveRecord::Base<br /> has_one :detail<br />end<br />class Detail < ActiveRecord::Base<br /> belongs_to :product<br />end<br /><br /><% form_for :product do |f| %><br /> <%= f.text_field :title %><br /> <% fields_for :detail do |detail| %><br /> <%= detail.text_field :manufacturer %><br /> <% end %><br /><% end %><br /><br /><br />class Product < ApplicationController<br /> def create<br /> @product = Product.new(params[:product])<br /> @details = Detail.new(params[:detail])<br /><br /> Product.transaction do<br /> @product.save!<br /> @details.product = @product<br /> @details.save!<br /> end<br /> end<br />end<br /><br /><br /># ~~~~~~~~~~~~~~~~~~~~~~~~~<br /># Nested Model Forms (one-to-one) After Rails 2.3 new feature<br /><br />class Product < ActiveRecord::Base<br /> has_one :detail<br /> accepts_nested_attributes_for :detail<br />end<br /><br /><% form_for :product do |f| %><br /> <%= f.text_field :title %><br /> <% f.fields_for :detail do |detail| %><br /> <%= detail.text_field :manufacturer %><br /> <% end %><br /><% end<br /><br /><br />class Product < ApplicationController<br /> def create<br /> @product = Product.new(params[:product])<br /> @product.save<br /> end<br />end<br /><br />#Nested Model Forms (one-to-many)<br /><br />class Project < ActiveRecord::Base<br /> has_many :tasks<br /> accepts_nested_attributes_for :tasks<br />end<br /><br />class Task < ActiveRecord::Base<br /> belongs_to :project<br />end<br /><br /><% form_for @project do |f| %><br /> <%= f.text_field :name %><br /> <% f.fields_for :tasks do |tasks_form| %><br /> <%= tasks_form.text_field :name %><br /> <% end %><br /><% end %><br /><br /><br />#===========================================<br />#Extract into Module Before<br /><br />class User < ActiveRecord::Base<br /> validates_presence_of :cellphone<br /> before_save :parse_cellphone<br /><br /> def parse_cellphone<br /> # do something<br /> end<br />end<br /><br />#<br />/lib/has_cellphone.rb<br />module HasCellphone<br /><br /> def self.included(base)<br /> base.validates_presence_of :cellphone<br /> base.before_save :parse_cellphone<br /> base.send(:include,InstanceMethods)<br /> base.send(:extend, ClassMethods)<br /> end<br /><br /> module InstanceMethods<br /> def parse_cellphone<br /> # do something<br /> end<br /> end<br /><br /> module ClassMethods<br /> end<br />end<br /><br /><br /><br />class User < ActiveRecord::Base<br /> include HasCellphone<br />end<br /><br /><br /><br />#=======================================<br /># Extract to composed class Before<br /><br /># == Schema Information<br /># address_city :string(255)<br /># address_street :string(255)<br />class Customer < ActiveRecord::Base<br /> def adddress_close_to?(other_customer)<br /> address_city == other_customer.address_city<br /> end<br /><br /> def address_equal(other_customer)<br /> address_street == other_customer.address_street &&<br /> address_city == other_customer.address_city<br /> end<br />end<br /><br /><br />#Extract to composed class (value object) After<br />class Customer < ActiveRecord::Base<br /> composed_of :address, :mapping => [ %w(address_street street),<br /> %w(address_city city) ]<br />end<br /><br />class Address<br /> attr_reader :street, :city<br /> def initialize(street, city)<br /> @street, @city = street, city<br /> end<br /><br /> def close_to?(other_address)<br /> city == other_address.city<br /> end<br /><br /> def ==(other_address)<br /> city == other_address.city && street == other_address.street<br /> end<br />end<br /><br /><br /><br /># Isolating Seed Data<br /># Before<br /><br />class CreateRoles < ActiveRecord::Migration<br /> def self.up<br /> create_table "roles", :force => true do |t|<br /> t.string :name<br /> end<br /><br /> #Move this to db/seeds.rb<br /> ["admin", "author", "editor","account"].each do |name|<br /> Role.create!(:name => name)<br /> end<br /><br /> end<br /><br /> def self.down<br /> drop_table "roles"<br /> end<br />end<br /><br /># After<br /># /db/seeds.rb (Rails 2.3.4)<br />["admin", "author", "editor","account"].each do |name|<br /> Role.create!(:name => name)<br />end<br />rake db:seed<br /><br />

Advanced Active Record Techniques: Best Practice Refactoring

Advanced Active Record Techniques: Best Practice Refactoring

<br />#p54<br /><br />class ArticleVersion < ActiveRecord::Base<br /> before_validation_on_create :set_version_number<br /> <br /> before_create :mark_related_links_not_current, :if => :current_version<br /><br /> private<br /> <br /> def current_version<br /> article.current_version<br /> end<br /> <br /> #下面兩個method 都會call 到 article.current_version <br /> #這樣就可以抽出來<br /> #然後mark_related_linkers_not_current 會需要判斷 article.current_version 的存在與否這也可以利用 Conditional Callback 來判斷<br /><br /> def set_version_number<br /> self.version = (current_version ? current_version.version : 0) + 1<br /> end<br /><br /> def mark_related_links_not_current<br /> current_version.relateds.each do |rel|<br /> rel.update_attribute(:current, false)<br /> end<br /> end<br />end<br /><br />#================================================================<br />#p74<br />class ArticleVersion < ActiveRecord::Base<br /> STATES = { :edit => 'Edit',<br /> :edit_check => 'Edit Check',<br /> :sub_edit => 'Sub Edit',<br /> :publish_ready => 'Publish Ready',<br /> :published => 'Published' }<br /><br /> STATES.each do |key, value|<br /> define_method "#{key}?", {<br /> self.state == "#{value}"<br /> }<br /> end<br />end<br /><br /><br />#=========================================================<br /># p84<br /><br />class Role < ActiveRecord::Base<br /> has_and_belongs_to_many :users<br /> validates_presence_of :name<br /> validates_uniqueness_of :name<br /><br /> def name=(value)<br /> write_attribute("name", value.downcase)<br /> end<br /><br /> # 想用symbol 拿值<br /> def self.[](name) # Get a role quickly by using: Role[:admin]<br /> self.find(:first, :conditions => ["name = ?", name.id2name])<br /> end<br /><br /> def add_user(user)<br /> self.users << user<br /> end<br /><br /> def delete_user(user)<br /> self.users.delete(user)<br /> end<br />end<br /><br /><br />#====================================================<br /># p91<br /><br />class User < ActiveRecord::Base<br /> has_many :roles<br />end<br /><br />class Role < ActiveRecord::Base<br /> TYPES = %w(admin editor writer guest)<br /> validates_inclusion_of :name, :in => TYPES<br /><br /> # 生成 class method<br /> class << self<br /> TYPES.each do |role_type|<br /> define_method "#{role_type}?" do<br /> # Exists? http://api.rubyonrails.org/classes/ActiveRecord/Base.html#M002268<br /> roles.exists?(:name => role_type)<br /> end<br /> end<br /> end<br />end<br /><br /><br /># =====================================================<br /># p96<br /><br /># Step 1<br />class User < ActiveRecord::Base<br /> include Addressable<br />end<br /><br />class Order < ActiveRecord::Base<br /> include Addressable<br />end<br /><br />module Addressable<br /> def self.included(base)<br /> base.validates_presence_of :billing_address_one, :billing_city, :billing_state,<br /> :billing_zip, :billing_country<br /> base.validates_presence_of :shipping_address_one, :shipping_city, :shipping_state,<br /> :shipping_zip, :shipping_country<br /> base.validates_format_of :billing_zip,<br /> :with => /\d{5}(-\d{4})?/,<br /> :if => Proc.new { |klass| klass.billing_country == "US" }<br /> base.validates_format_of :shipping_zip,<br /> :with => /\d{5}(-\d{4})?/,<br /> :if => Proc.new { |klass| klass.shipping_country == "US" }<br /> base.validates_format_of :billing_zip,<br /> :with => /[a-zA-Z]\d[a-zA-Z] \d[a-zA-Z]\d/,<br /> :if => Proc.new { |klass| klass.billing_country == "CA" }<br /> base.validates_format_of :shipping_zip,<br /> :with => /[a-zA-Z]\d[a-zA-Z] \d[a-zA-Z]\d/,<br /> :if => Proc.new { |klass| klass.shipping_country == "CA" }<br /> end<br />end<br /><br /><br /><br /># Step 2<br /><br />class User < ActiveRecord::Base<br /> has_address :shipping<br /> has_address :billing<br /> has_many :orders<br />end<br /><br />module Addressable<br /> class << self<br /> def included(base)<br /> base.extend ClassMethods<br /> end<br /> end<br /><br /> module ClassMethods<br /> def has_address(name = "")<br /> name = "#{name}_" unless name.blank?<br /> validates_presence_of "#{name}address_one", "#{name}city",<br /> "#{name}state_province", "#{name}postal_code", "#{name}country"<br /> validates_format_of "#{name}postal_code", :with => /\d{5}(-\d{4})?/,<br /> :if => Proc.new { |user| user["#{name}country"] == "US" }<br /> validates_format_of "#{name}postal_code", :with => /[a-zA-Z]\d[a-zA-Z] \d[a-zA-Z]\d/,<br /> :if => Proc.new { |user| user["#{name}country"] == "CA" }<br /> end<br /> end<br />end<br /><br />ActiveRecord::Base.send :include, Addressable<br /><br /><br /><br /># Step 3<br /><br /> <br />class User < ActiveRecord::Base<br /> has_address :shipping<br /> has_address :billing<br /> <br /> has_many :orders<br />end<br /><br />module Addressable<br /> class << self<br /> def included(base)<br /> base.extend ClassMethods<br /> end<br /> end<br /><br /> module ClassMethods<br /> def has_address(name)<br /> name << “_” unless name.blank?<br /> validates_presence_of "#{name}address_one", "#{name}city",<br /> "#{name}state_province", "#{name}postal_code", "#{name}country"<br /> validates_format_of "#{name}postal_code", :with => /\d{5}(-\d{4})?/,<br /> :if => Proc.new { |user| user["#{name}country"] == "US" }<br /> validates_format_of "#{name}postal_code", :with => /[a-zA-Z]\d[a-zA-Z] \d[a-zA-Z]\d/,<br /> :if => Proc.new { |user| user["#{name}country"] == "CA" }<br /> composed_of "#{name}address", :class_name => “Address”,<br /> :mapping => [ ["#{name}address_one", "address_one"],<br /> ["#{name}address_two", "address_two"],<br /> ["#{name}city", "city"],<br /> ["#{name}state_province", "state_province"],<br /> ["#{name}postal_code", "postal_code"]<br /> ["#{name}country", "country"] ]<br /> end<br /> end<br />end<br /><br />ActiveRecord::Base.send :include, Addressable<br /><br />

Rails Code Review PDF

http://peepcode.com/products/rails-code-review-pdf

<br />#:select and :include<br /><br />#If a query contains an :include directive, any :select<br />options will be ignored. For example you might expect this<br />to return an array of ids only. Not so!<br /><br /># This won't work as you expect<br />Farm.find(:all, {<br /> :select => "farms.id, chickens.id",<br /> :include => :chickens<br />})<br /><br />#use :join with :select<br />The way around this is to code the :join explicitly.<br /> Farm.find(:all, {<br /> :select => "farms.id, chickens.id",<br /> :join => "LEFT JOIN ..."<br /> })<br /><br />LEFT OUTER JOIN chickens ON chickens.farm_id =<br />farms.id<br /><br />

Enable or fix logging for HAProxy load balancer

Enable or fix logging for HAProxy load balancer

On a RedHat/CentOS server, edit the value of SYSLOGD_OPTIONS in /etc/sysconfig/syslog:

SYSLOGD_OPTIONS=”-m 0 -r”


On a Debian/Ubuntu server, edit the value of SYSLOGD in /etc/default/syslogd:

SYSLOGD=”-r”


/etc/syslog.conf:

local0.* /var/log/haproxy.log


restart syslog service to apply changes:

service syslog restart

request host, query paramters, header

登入登出轉址設計
<br />request.env['QUERY_STRING']<br />"cat=futures&sort=latest"<br /><br />#full url<br />request.url<br />#http://localhost:3000/home/<br /><br />#path<br />request.request_uri<br />"/home/"<br /><br />#host_and_port<br />request.host_with_port<br /><br />#source code http://api.rubyonrails.org/classes/ActionController/Base.html<br /> when :back<br /> if referer = request.headers["Referer"]<br /> redirect_to(referer, :status=>status)<br /> else<br /> raise RedirectBackError<br /> end<br /><br /><br />

multi-step

RoR Multi-step forms

private<br /> def get_partial_user_from_session<br /> unless @session['partial_user'].nil?<br /> @user = @session['partial_user']<br /> else<br /> @user = User.new<br /> end<br /> end<br /><br /> def save_partial_user_in_session<br /> unless @user.nil?<br /> @session['partial_user'] = @user<br /> end<br /> end<br /> <br /> # Might be a good addition to AR::Base<br /> def valid_for_attributes( model, attributes )<br /> unless model.valid?<br /> errors = model.errors<br /> our_errors = Array.new<br /> errors.each { |attr,error|<br /> if attributes.include? attr<br /> our_errors << [attr,error]<br /> end<br /> }<br /> errors.clear<br /> our_errors.each { |attr,error| errors.add(attr,error) }<br /> return false unless errors.empty?<br /> end<br /> return true<br /> end<br /><br /><br />#To ensure the errors are cleared out properly on each request add a before_filter with the following:<br /> def clear_stage_errors<br /> unless @session['partial_user'].nil?<br /> @session['partial_user'].errors.clear<br /> end<br /> end<br /><br />=begin<br />You can use<br />get_partial_user_from_session<br />and<br />save_partial_user_in_session<br />as before and after filters, respectively, so you only have to reference @user in your multi-step controller.<br />=end<br /><br />#A clean way to arrange the view is to have each step in its own partial, and set a variable such as<br />@current_stage<br />#in your controller, then in your view just do something like:<br /><%= start_form_tag({:action=> "signup"} , { :name => 'signupform' }) %><br /><%= hidden_field_tag "changeCountry" %><br /><%= hidden_field_tag "current_stage", "#{@current_stage}"%><br /><br /><h2>Registration Process</h2><br /><%= @flash['notice'] %><br /><br /><%= render_partial "#{@current_stage}" %><br /> <br /><%= end_form_tag %><br /><br /><br />#Your signup controller action could something similar to this:<br /> def signup<br /> case @request.method<br /> when :post<br /> @current_stage = @params['current_stage']<br /> if @current_stage == "stage1"<br /> @user.attributes = @params['user'] <br /> @current_stage = "stage2" if valid_for_attributes(@user,["login","attribute2"])<br /> end<br /> elsif @current_stage == "stage2"<br /> @user.attributes = @params['user'] <br /> @current_stage = "stage3" if valid_for_attributes(@user,["attribute3","attribute4"])<br /> elsif @current_stage == "stage3"<br /> @user.attributes = @params['user']<br /> <br /> if @user.save<br /> @session[:user] = User.authenticate(@user.login, @params['user']['password'])<br /> flash['notice'] = "Signup successful"<br /> redirect_to :action => "home"<br /> end<br /> end<br /> when :get<br /> @current_stage = "stage1"<br /> end<br /> end<br /><br /><br /><br />#==========================================<br />=begin<br />Comments on this post<br />bmarini posts on May 19, 2008 at 12:56<br />I took your partial validation idea and included it in AR Base<br />=end<br />module ActiveRecord<br /> module Validations<br /> module Partial<br /> def valid_for_attributes?( *attr_names )<br /> return validate_for_attributes(attr_names)<br /> end<br /> <br /> def validate_for_attributes( *attr_names )<br /> attr_names.map! {|a| a.to_s }<br /> <br /> unless valid?<br /> our_errors = Array.new<br /> errors.each { |attr,error|<br /> if attr_names.include? attr<br /> our_errors << [attr,error]<br /> end<br /> }<br /> <br /> errors.clear<br /> our_errors.each { |attr,error| errors.add(attr,error) }<br /> return false unless errors.empty?<br /> end<br /> return true<br /> end<br /> <br /> end<br /> end<br />end<br /><br />ActiveRecord::Base.class_eval do<br /> include ActiveRecord::Validations::Partial<br />end<br /><br />=begin<br />cgunther posts on Jul 02, 2009 at 11:40<br />bmarini, I think there is a bug in your code.<br /><br />When I called:<br />=end<br />@order.valid_for_attributes? 'first_name', 'last_name'<br /><br />=begin<br />It always passed validation. The error was the asterisk in front of attr_names on validate_for_attributes. It was being passed an array as the first attribute and when you run map! on it, it was converting the entire array to a single string (first_namelast_name).<br /><br />Here's the code that works for me:<br />=end<br />module ActiveRecord<br /> module Validations<br /> module Partial<br /> def valid_for_attributes?( *attr_names )<br /> return validate_for_attributes(attr_names)<br /> end<br /> <br /> def validate_for_attributes( attr_names )<br /> attr_names.map! {|a| a.to_s }<br /> <br /> unless valid?<br /> our_errors = Array.new<br /> errors.each { |attr,error|<br /> if attr_names.include? attr<br /> our_errors << [attr,error]<br /> end<br /> }<br /> <br /> errors.clear<br /> our_errors.each { |attr,error| errors.add(attr,error) }<br /> return false unless errors.empty?<br /> end<br /> return true<br /> end<br /> <br /> end<br /> end<br />end<br /><br />ActiveRecord::Base.class_eval do<br /> include ActiveRecord::Validations::Partial<br />end<br /><br /><br />#The main difference is that if you call validate_for_attributes directly, you have to pass it an array.<br /><br />#Chris Gunther

render outside your controller

Rails: Calling render() outside your Controllers
Calling Rails Render Partial in a Model or Background Task


<br /># lib/render_anywhere.rb<br /># <br /># Render templates outside of a controller or view.<br /># <br /># Simply mixin this module to your existing class, for example:<br /># <br /># class MyTemplater < ActiveRecord::Base<br /># include RenderAnywhere<br /># <br /># And you can use render() method that works the same as ActionView::Base#render<br /># <br /># obj = MyTemplater.new<br /># obj.html = obj.render :file => '/shared/header'<br /># <br /># <br />module RenderAnywhere<br /> <br /> class DummyController<br /> def logger<br /> RAILS_DEFAULT_LOGGER<br /> end<br /> def headers<br /> {}<br /> end<br /> end<br /> <br /> def render(options, assigns = {})<br /> viewer = ActionView::Base.new(Rails::Configuration.new.view_path, assigns, DummyController.new)<br /> viewer.render options<br /> end<br /> <br /> def template_exists?(path, assigns = {})<br /> viewer = ActionView::Base.new(Rails::Configuration.new.view_path, assigns, DummyController.new)<br /> viewer.pick_template_extension(path) rescue false<br /> end<br />end<br /><br />class Page < ActiveRecord::Base<br /><br /> def write_cache<br /> self.cached_content = ActionView::Base.new(Rails::Configuration.new.view_path).render(:partial => "pages/show", :locals => {:page => self})<br /> self.save<br /> end<br /><br />end

Turning web server configuration

Setting Static Asset Expires Headers with nginx and Passenger

Nginx

location ~* \.(ico|css|js|gif|jpe?g|png)(\?[0-9]+)?$ {
    expires max;
    break;
}

redirect permanent

Permanent Redirect with HTTP 301

#Apache
    RewriteCond %{HTTP_HOST}   17\.ooxx\.com [NC]
    RewriteRule ^/(.*)         http://17.ooxx.com.tw/$1 [L,R=permanent]

#Nginx
    if ($host ~* ^17.ooxx\.com) {
      rewrite ^/(.*) http://17.ooxx.com.tw/$1 permanent;
    }

META HTTP-EQUIV="refresh" 實現網頁自動跳轉

META HTTP-EQUIV="refresh" 實現網頁自動跳轉

<br />< meta http-equiv="Refresh" content="秒數; url=跳轉的文件或地址" > <br /><br />< head > <br /> < meta http-equiv="Refresh" content="3;url=http://www.haishui.net"><br />< /head > <br /><br />多個內容相似而背景不同的頁面，讓其每隔一定時間自動相互跳轉。 <br />

rails default environment

~/.bashrc

export PATH=$PATH:/opt/ruby-enterprise/bin
export RAILS_ENV=production

nginx memo

Nginx泛域名解析及Rewrite重定向普通頁面及帶參數的頁面
Nginx "how to" - Fast and Secure Web Server
Nginx Location



靜態地址重定向到帶參數的動態地址

rewrite "^(.*)/service/(.*)\.html$" $1/service.php?sid=$2 permanent;

帶參數的動態地址重定向到靜態地址

if ($query_string ~* id=(.*)) {
    set $id $1;
    rewrite "^(.*)/article.asp$" $1/article/$id.htm last;
}

舉例:
abc.domian.com/sort/2 => abc.domian.com/index.php?act=sort&name=abc&id=2

if ($host ~* (.*)\.domain\.com) {
    set $sub_name $1;
    rewrite ^/sort\/(\d+)\/?$ /index.php?act=sort&cid=$sub_name&id=$1 last;
}

Nginx Rewrite Flags
* last 相當於Apache裡的[L]標記，表示完成rewrite
* break 終止匹配, 不再匹配後面的規則
* redirect 返回302臨時重定向
* permanent 返回301永久重定向

Nginx正則表達式匹配
* ~ 為區分大小寫匹配
* ~* 為不區分大小寫匹配
* !~和!~*分別為區分大小寫不匹配及不區分大小寫不匹配

Nginx文件及目錄匹配
* -f和!-f用來判斷是否存在文件
* -d和!-d用來判斷是否存在目錄
* -e和!-e用來判斷是否存在文件或目錄
* -x和!-x用來判斷文件是否可執行

Nginx全局變量
$args
$content_length
$content_type
$document_root
$document_uri
$host
$http_user_agent
$http_cookie
$limit_rate
$request_body_file
$request_method
$remote_addr
$remote_port
$remote_user
$request_filename
$request_uri
$query_string
$scheme
$server_protocol
$server_addr
$server_name
$server_port
$uri

restart nginx

 
alias startnginx='sudo /opt/nginx/sbin/nginx' 
alias stopnginx='sudo kill `cat /opt/nginx/logs/nginx.pid `' 
alias restartnginx='stopnginx; startnginx' 

transcation

Transaction in Rails
Working with transactions in Rails
<br />transaction do<br /> first.save!<br /> second.save!<br /> third.save!<br /> fourth.save!<br />end<br /><br /> Course.transaction do<br /> @course.save!<br /> read_directory(@course.folder_title).each do |f|<br /> lo = LearningObject.new<br /> lo.course_id, lo.title = @course.id, f.gsub('_',' ')<br /> lo.save!<br /> end<br /> end<br />

ssl apache nginx configuration

http://articles.slicehost.com/2010/1/11/managing-ssl-certificates-1
http://articles.slicehost.com/2010/1/11/managing-ssl-certificates-2
Nginx SSL 實務
SSL Certificate Installation in Nginx
Configuring HTTPS servers

ssl 設定的file 有三種 伺服器憑證, 中繼憑證, RSA key
各種web server 吃的方式不同

Nginx 設定

listen  ip.address:443; #監聽HTTPS, 通常是Port 443
ssl  on;
ssl_certificate  /path/to/server.crt; 
ssl_certificate_key  /path/to/private.key; #這是伺服器用的RSA Key


#server.crt要用發下來的伺服器憑證與中繼憑證合併產生:
cat domain_name.crt ca_bundle.crt  > server.cr

SSLCertificateFile /etc/ssl/apache_ca.crt      #這是伺服器憑證
SSLCertificateKeyFile /etc/ssl/www.goyou.com.tw.key   
SSLCertificateChainFile /etc/ssl/chain.crt    #中繼憑證

nginx , page cache, capistrano

Segregated page cache storage
Rails page caching vs nginx Restful route 可能會造成有相同的html, like index and create, 所以利用nginx 做一些檢查來避免
nginx rewrite rules with Passenger

if (-f $request_filename) {
  break;
}

# cached pages
#set $cache_extension '';
#if ($request_method = GET) {
#  set $cache_extension '.html';
#}

# the above is a hack because nginx doesn't allow nested or ANDed ifs
#if (-f $request_filename$cache_extension) {
#  rewrite (.*) $1.html break;
#}

# 這個才有用 上面那些都沒用 orz, 用$uri 才有用
if (-f $document_root/cache/$uri/index.html) {
  rewrite (.*) /cache/$1/index.html break;
}

if (-f $document_root/cache/$uri.html) {
  rewrite (.*) /cache/$1.html break;
}


# everything else goes to the mongrel cluster
if (!-f $request_filename) {
  proxy_pass http://mongrels;
  break;
}

#In config/environments/production.rb, tell Rails to put cached pages in the public/cache directory.

config.action_controller.page_cache_directory = File.join(RAILS_ROOT, 'public', 'cache')

#In nginx.conf, set up the precedence for locating static files. First look in public for regular static files. Next look in the cache directory for an exact match for the url. Lastly, look in the cache directory for the url with .html appended. That will let you cache pages for regular URLs with no .html extension as well as ones with extensions like .xml, .atom, .json, etc.

  if (-f $request_filename) { 
    break; 
  }

#  if (-f /cache$request_filename) { 
#    rewrite (.*) /cache$1 break;
#    break; 
#  }

#  if (-f /cache$request_filename.html) { 
#    rewrite (.*) /cache$1.html break;
#    break; 
#  }

#The capistrano recipes have to do a couple things. You need to create the shared/cache directory when setting up the deployment.

after "deploy:setup", "create_page_cache"
task :create_page_cache, :roles => :app do
  run "umask 02 && mkdir -p #{shared_path}/cache"
end


after "deploy:update_code","symlink_shared_dirs"
task :symlink_shared_dirs, :roles => :app, :except => {:no_release => true, :no_symlink => true} do
    run <<-CMD
      cd #{release_path} &&
      ln -nfs #{shared_path}/cache #{release_path}/public/cache
    CMD
end

#When doing a deploy, the standard behavior is to flush the cache, just to be on the safe side. If you want to retain cached pages, as when making a change you know won't affect rendering, tell capistrano not to flush.

# default behavior is to flush page cache on deploy
set :flush_cache, true

# page cache management
task :keep_page_cache do
  set :flush_cache, false
end

after "deploy:cleanup", "flush_page_cache"
task :flush_page_cache, :roles => :app do
  if flush_cache
    run <<-CMD
      rm -rf #{shared_path}/cache/*
    CMD
  end
end

#With the above setup, you can deploy and retain the cache with the following capistrano command:
$ cap keep_page_cache deploy

Moneta, memcache

Moneta: 提供 key/value stores 的統一介面
moneta github
handcache github

<br />#config/environment.rb<br />begin<br /> CacheStore = Moneta::Memcache.new(:server => "127.0.0.1")<br />rescue<br /> CacheStore = Moneta::BasicFile.new(:path => "tmp")<br />end<br /><br />#lib/handcache.rb<br />#handcache lib<br /><br />#controller<br />@user = Handcache.get_and_set("first-user", :expires_in => 30) do<br /> User.first.inspect<br />end<br /><br />#view<br /><%= Handcache.get_and_set( dom_id(@post), :expires_in => 60 ) do<br /> render :partial => "post"<br />end %><br /><br /><br />

heroku 上 你要 它卻沒有的gem

Automatically generate Heroku .gems file

用個rake 幫你生這個file
namespace :gems do<br /> desc "Generate .gems file for Heroku"<br /> task :heroku_spec => :environment do<br /> require 'open-uri'<br /> installed_gems = []<br /> url = "http://installed-gems.heroku.com/"<br /> open(url).read.scan(/<li>(\w+) [^<]*<\/li>/) do |w| <br /> installed_gems << w.first<br /> end<br /><br /> gems = Rails.configuration.gems<br /> <br /> # output .gems<br /> dot_gems = File.join(RAILS_ROOT, ".gems")<br /> File.open(dot_gems, "w") do |f|<br /> output = []<br /> gems.each do |gem|<br /> next if installed_gems.include?(gem.name)<br /> spec = "#{gem.name} --version '#{gem.version_requirements.to_s}'"<br /> spec << " --source #{gem.source}" if gem.source<br /> output << spec<br /> end<br /> f.write output.join("\n")<br /> puts output.join("\n")<br /> end<br /> end<br />end