Ruby on Rails code tips _ruby Topics

Git warehouse output
Git Archive--format=tar--prefix=actasfavor/head | (cd/home/holin/work/&& Tar XF-)
Output to the/home/holin/work/actasfavor/directory

Posted by Holin at May 16, 2008 16:42
Load controller and model in plugins

# Include Hook code here
Require ' Act_as_favor '
# Make plugin controller, model, helper available to app
Config.load_paths + =%w (#{actasfavor::P lugin_controller_path} #{actasfavor::P Lugin_helper_path} #{ActAsFavor:: Plugin_models_path})
Rails::initializer.run (: set_load_path, config)
# Require the Controller
Require ' Favors_controller '
# Require models
Require ' favor '

Posted by Holin at May 15, 2008 15:36
Use the top 5 commands most frequently
History | awk {' Print $ '} | Sort | uniq-c | sort-k1-rn| Head-n5

Posted by Holin at May 15, 2008 10:40
Sort by an attribute of an array element
@users. sort! {|a, b| a.last <=> B.last}

Posted by Holin at May 11, 2008 14:35
Back up a database by date
Mysqldump db_name-uroot > "/root/db_backup/kaoshi_web_ ' date +"%y-%m-%d "'. sql"

Posted by Holin at May 08, 2008 12:05
Manual cache data with memcached

sql = "SELECT * FROM blogs LIMIT 100"
Blog.class
k = md5.new (SQL)
@blogs = Cache.get k
If @blogs. Blank?
@blogs = blog.find_by_sql (SQL)
Cache.put K, @blogs, 60*30 #expire after 30min
End
Memcache-client 1.5.0:
Get (key, expiry = 0)
Put (key, value, expiry = 0)

Posted by Devon at May 04, 2008 20:39
Shuffle an array

Class Array
Def Shuffle
sort_by {Rand}
End
def shuffle!
Self.replace Shuffle
End
End

Posted by Holin at May 04, 2008 15:39
Make all the Ajax requests Render:layout

def render (*args)
Args.first[:layout] = False if request.xhr? and Args.first[:layout].nil?
Super
End

Posted by Devon at May 03, 2008 10:53
Find with Hash

Event.find (
: All,
: Conditions => ["title Like:search or description Like:search",
{: Search => "%tiki%"}]
)

Posted by Devon at May 03, 2008 10:49
Execute SQL statement Script

Mysql-uroot-p123<<end
Use Dbame;
Delete from results;
Delete from examings;
Quit
End

Posted by Holin at May 01, 2008 12:14
SQL Transaction in Rails

def Fetch_value
sql = Activerecord::base.connection ();
Sql.execute "SET autocommit=0";
Sql.begin_db_transaction
ID, value =
Sql.execute ("SELECT ID, value from sometable WHERE used=0 LIMIT 1 for UPDATE"). Fetch_row;
Sql.update "Update sometable SET used=1 WHERE id=#{id}";
Sql.commit_db_transaction
Value
End

Posted by Holin at April 30, 2008 09:37
Display the dynamic effect of a Flash message

<% if flash[:warning] or Flash[:notice]%>
<div id= "notice" <% if flash[:warning]%>class= "Warning" <% end%>>
<%= Flash[:warning] | | Flash[:notice]%>
</div>
<script type= "Text/javascript" >
SetTimeout ("New Effect.fade" (' notice '); ", 15000)
</script>
<% End%>
Automatically notice Div disappears after 15000 milliseconds.

Posted by Devon at April 29, 2008 13:02
Deleting constants in an environment

Object.send (: Remove_const,: A)
>> Math
=> Math
>> object.send (: Remove_const, Math)
=> Math
>> Math
NAMEERROR:UNINITIALIZED constant Math

Posted by Devon at April 28, 2008 18:24
Manually plus Authenticity_token
<div style= "margin:0;padding:0" ><input name= "Authenticity_token" type= "hidden" value= "<%= form_ Authenticity_token%> "/></div>

Posted by Devon at April 28, 2008 14:24
Rails group_by

<% @articles. group_by (&:d ay). Each do |day, articles| %>
<div id= ' Day ' style= "padding:10px 0;" >
<%= render:p artial => ' article ', collection, => articles
</div>
<% End%>
Articles GROUP BY days

Posted by Devon at April 25, 2008 22:32
Read and write files

# Open and read from a text file
# that's since a block is given, file would
# automatically be closed ' The block terminates
File.Open (' p014constructs.rb ', ' r ') do |f1|
While line = F1.gets
Puts line
End
End
# Create A new file and write to it
File.Open (' test.rb ', ' W ') do |f2|
# use ' \ n ' for two lines of text
F2.puts "Created by Satish\nthank god!"
End

Posted by Holin at April 17, 2008 02:10
Traverse Directory
Dir.glob (File.join (' app/controllers ', "* *", "*_controller.rb")) {|filename| puts filename}

Posted by Holin at April 16, 2008 15:28
String to model
1
2
>> ' Tag_course '. Camelize.constantize.find (: a)
=> #<tagcourse Id:7, tag_id:83, course_id:2>
*camelize (Lower_case_and_underscored_word, first_letter_in_uppercase = True) *
By default, the Camelize converts strings to uppercamelcase. If the argument to Camelize are set to ": Lower" then camelize produces.
*constantize (Camel_cased_word) *
Constantize tries to find a declared constant with the name specified in the string. It raises a nameerror when the ' name is ' is ' not ' in CamelCase ' or ' is ' not ' initialized.

Posted by Devon at April 07, 2008 17:32
Call proc
1
2
3
A = proc.new {|i| puts i}
a[' haha ']
A.call (' hehe ')

Posted by Holin at March 28, 2008 23:10
The host static file in Rails
1
2
Config.action_controller.asset_host = "Http://assets.example.com"
Config.action_controller.asset_host = "Http://assets-%d.example.com"
The Rails Image_path and similar helper methods would then use this host to reference files into the public directory.
The second line would distribute asset requests across assets-0.example.com,assets-1.example.com, Assets-2.example.com, and assets-3.example.com.

Posted by Devon at March 26, 2008 18:18
Package gems into the project directory

$ mkdir Vendor/gems
$ CD Vendor/gems
$ gem Unpack Hpricot
Unpacked gem: ' hpricot-0.4 '
Config.load_paths + + dir["#{rails_root}/vendor/gems/**"].map do |dir|
File.directory? (lib = "#{dir}/lib")? Lib:dir
End

Posted by Devon at March 26, 2008 18:12
Executing code in a file in the current context

Instance_eval (File.read (' Param.txt '))
# such as
@father = ' father '
Instance_eval ("puts @father")
#Produces:
#Father

Posted by Holin at March 20, 2008 01:13
Add the current file directory to the Require path

$LOAD _path << File.expand_path (File.dirname (__file__))
# or
$: << File.expand_path (File.dirname (__file__))
# This one puts current path before to the other path.
$:.unshift (File.expand_path (File.dirname (__file__))
*__ file __* Current files path

Posted by Holin at March 19, 2008 01:40
Multi-field Fuzzy search

conditions = []
[: Name,: School,:p rovince,: city].each {|attr| conditions << profile.send (: Sanitize_sql, ["#{attr} like?", "%#{pa rams[:q]}% "]) if PARAMS[:Q]}
conditions = Conditions.any?? Conditions.collect {|c| "(#{c})"}.join (' OR '): Nil
In the profile, press name, school, province, city Blur search

Posted by Devon at March 17, 2008 17:25
Nginx Startup script


#! /bin/sh
# Chkconfig:-58 74
# Description:nginx is the Nginx daemon.
# Description:startup script for Nginx webserver on Debian. Place IN/ETC/INIT.D and
# run ' sudo update-rc.d nginx defaults ', or use the appropriate command on your
# distro.
#
# Author:ryan Norbauer
# Modified:geoffrey Grosenbach http://topfunky.com
# Modified:david Krmpotic http://davidhq.com
Set-e
Path=/usr/local/sbin:/usr/local/bin:/sbin:/bin:/usr/sbin:/usr/bin
desc= "Nginx Daemon"
Name=nginx
daemon=/usr/local/nginx/sbin/$NAME
Configfile=/usr/local/nginx/conf/nginx.conf
daemon=/usr/local/nginx/sbin/$NAME
Configfile=/usr/local/nginx/conf/nginx.conf
pidfile=/usr/local/nginx/logs/$NAME. PID
Scriptname=/etc/init.d/$NAME
# gracefully Exit if the package has been removed.
Test-x $DAEMON | | Exit 0
D_start () {
$DAEMON-C $CONFIGFILE | | Echo-en "\ already Running"
}
D_stop () {
Kill-quit ' Cat $PIDFILE ' | | Echo-en "\ Not Running"
}
D_reload () {
Kill-hup ' Cat $PIDFILE ' | | Echo-en "\ can ' t reload"
}
Case "$" in
Start
Echo-n "Starting $DESC: $NAME"
D_start
echo "."

Stop
Echo-n "Stopping $DESC: $NAME"
D_stop
echo "."

Reload
Echo-n "Reloading $DESC configuration ..."
D_reload
echo "."

Restart)
Echo-n "Restarting $DESC: $NAME"
D_stop
# One second might not being time enough for a daemon to stop,
# If this happens, D_start'll fail (and dpkg would break if
# The package is being upgraded). Change the timeout if needed
# be, or the d_stop to have start-stop-daemon the use--retry.
# Notice that using--retry slows down the shutdown process
# somewhat.
Sleep 1
D_start
echo "."

*)
echo "Usage: $SCRIPTNAME {start|stop|restart|reload}" >&2
Exit 3

Esac
Exit 0
Write files to/etc/init.d/nginx
sudo chmod +x/etc/init.d/nginx
Test to run correctly
Sudo/etc/init.d/nginx start
Set Auto Start
Sudo/sbin/chkconfig--level 345 Nginx on

Posted by Devon at March 16, 2008 12:26
Link_to_remote static page
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<%= link_to_remote "update post": Update => ' Post ': Method => ' Get ',: url => '/post_1.html '%>
<div id= ' Post ' ></div>
Change the URL to the address of the static surface page.

Posted by Devon at March 16, 2008 11:07
In_place_editor for rails2.0

Module Inplacemacroshelper
# makes an HTML element specified by the DOM ID +field_id+ become a In-place
# Editor of a property.
#
# A form is automatically created and displayed the user clicks the element,
# something like this:
# <form id= "Myelement-in-place-edit-form" target= "specified URL" >
# <input Name= "value" text= "The content of MyElement"/>
# <input Type= "Submit" value= "OK"/>
# <a onclick= "JavaScript to cancel" editing ">cancel</a>
# </form>
#
# The form is serialized and sent to the server using a AJAX call, the action on
# The server should process the value and return the updated value of
# The Reponse. The element would automatically be updated with the changed value
# (as returned from the server).
#
# Required +options+ are:
# <tt>:url</tt&gt:: Specifies the URL where the updated value should
# be sent after the user presses ' OK '.
#
# addtional +options+ are:
# <tt>:rows</tt&gt:: Number of rows (more than 1 would use a TEXTAREA)
# <tt>:cols</tt&gt:: Number of characters the text input should span (works for both input and TEXTAREA)
# <tt>:size</tt&gt:: Synonym For:cols when using a single line text input.
# &LT;TT&GT;:CANCEL_TEXT&LT;/TT&GT;:: The text on the cancel link. (Default: "Cancel")
# &LT;TT&GT;:SAVE_TEXT&LT;/TT&GT;:: The text on the Save link. (Default: "OK")
# <tt>:loading_text</tt&gt:: The text to display while the ' data is ' being loaded from the server (default: "Loadi Ng ... ")
# <tt>:saving_text</tt&gt:: The text to display when submitting to the server (default: "Saving ...")
# <tt>:external_control</tt&gt:: The ID of a external control used to enter edit mode.
# <tt>:load_text_url</tt&gt:: URL where initial value of editor (content) is retrieved.
# <tt>:options</tt&gt:: Pass through options to the AJAX call (the prototype ' s ajax.updater)
# <tt>:with</tt&gt:: JavaScript snippet that should return what are to be sent
# in the AJAX call, +form+ are an implicit parameter
# <tt>:script</tt&gt:: Instructs the In-place editor to evaluate the remote JavaScript response (Default:false)
# <tt>:click_to_edit_text</tt>::the text shown during mouseover the editable text (default: "Click to edit")
def in_place_editor (field_id, options = {})
function = "New Ajax.inplaceeditor" ("
function << "' #{field_id} ',"
function << "' #{url_for (Options[:url])} '"
Js_options = {}
If Protect_against_forgery?
Options[:with] | | = "Form.serialize (Form)"
Options[:with] + + ' &authenticity_token= ' + encodeuricomponent (' #{form_authenticity_token} ')
End
js_options[' canceltext '] =% (' #{options[:cancel_text]} ') if Options[:cancel_text]
js_options[' oktext '] =% (' #{options[:save_text]} ') if Options[:save_text]
js_options[' loadingtext '] =% (' #{options[:loading_text]} ') if Options[:loading_text]
js_options[' savingtext '] =% (' #{options[:saving_text]} ') if Options[:saving_text]
js_options[' rows '] = Options[:rows] if options[:rows]
js_options[' cols '] = Options[:cols] if Options[:cols]
js_options[' size '] = Options[:size] if options[:size]
js_options[' externalcontrol '] = "' #{options[:external_control]} '" If Options[:external_control]
js_options[' loadtexturl '] = "' #{url_for (Options[:load_text_url])} '" If Options[:load_text_url]
js_options[' ajaxoptions '] = options[:options] if options[:options]
# js_options[' evalscripts '] = Options[:script] if Options[:script]
js_options[' htmlresponse '] =!options[:script] if Options[:script]
Js_options[' callback '] = "function (form) {return #{options[:with]}}" if Options[:with]
js_options[' clicktoedittext '] =% (' #{options[:click_to_edit_text]} ') if Options[:click_to_edit_text]
js_options[' textbetweencontrols '] =% (' #{options[:text_between_controls]} ') if Options[:text_between_controls]
function << (', ' + options_for_javascript (js_options)) unless Js_options.empty?
function << ') '
Javascript_tag (function)
End
# renders the value of the specified object and method with In-place editing capabilities.
Def in_place_editor_field (object, method, Tag_options = {}, in_place_editor_options = {})
Tag =:: Actionview::helpers::instancetag.new (Object, method, self)
Tag_options = {: Tag => "span": ID => "#{object}_#{method}_#{tag.object.id}_in_place_editor",: Class => "In_ Place_editor_field "}.merge! (tag_options)
In_place_editor_options[:url] = In_place_editor_options[:url] | | Url_for ({: Action => "Set_#{object}_#{method}",: ID => tag.object.id})
Tag.to_content_tag (Tag_options.delete (: Tag), tag_options) +
In_place_editor (Tag_options[:id], in_place_editor_options)
End
End
Resolves the actioncontroller::invalidauthenticitytoken error that occurs when the in_place_editor is used with the rails2.0 version.

Posted by Devon at March 15, 2008 16:20
Capture in view

<% @greeting = capture do%>
Welcome to my shiny new web page! The date and the IS
<%= Time.now%>
<% End%>
<body>
<b><%= @greeting%></b>
</body>The Capture method allows your to extract part of a template into a variable. You can then the variable anywhere in your templates or layout.

Posted by Devon at March 13, 2008 14:06
Use different layout in Before_filter
Before_filter proc.new {|controller| layout ' iframe ' unless controller.request.env[' http_referer '] =~/localhost/}
If you are not accessing this site from localhost, use the layout of the IFRAME

Posted by Devon at March 11, 2008 17:38
Get Http_referer in Rails
request.env["Http_referer"]
The parameters that can be taken include:
Server_name:localhost
Path_info:/forum/forums
http_user_agent:mozilla/5.0 (Macintosh; U Intel Mac OS X; EN) applewebkit/522.11 (khtml, like Gecko) version/3.0.2 safari/522.12
Http_accept_encoding:gzip, deflate
Script_name:/
server_protocol:http/1.1
http_host:localhost:3000
Http_cache_control:max-age=0
Http_accept_language:en
remote_addr:127.0.0.1
Server_software:mongrel 1.1.3
Request_path:/forum/forums
Http_referer:http://localhost:3000/
Http_cookie: _matchsession=bah7bzomy3nyzl9pzcilnwjinzg4nduzowqznwfhztq4mgrkntuwyzc0mdc5% 250azgyicmzsyxnosum6j0fjdglvbknvbnryb2xszxi6okzsyxnoojpgbgfzaehh%250ac2h7aay6ckb1c2vkewa% 253D268E6091590591D959128F3B17B62FF46244A0A3; _slemail=temp%40email.com; _SLHASH=9DFD86431742273E3E96E06A1C20541D69F74DC9; _haha_session=bah7biikzmxhc2hjqzonqwn0aw9uq29udhjvbgxlcjo6rmxhc2g6okzsyxno%250asgfzahsabjokqhvzzwr7aa%253d% 253d--96565e41694dc839bd244af40b5d5121a923c8e3
http_version:http/1.1
Request_uri:/forum/forums
Server_port: "3000"
gateway_interface:cgi/1.2
http_accept:text/xml,application/xml,application/xhtml+xml,text/html;q=0.9,text/plain;q=0.8,image/png,*/*;q= 0.5
Http_connection:keep-alive
Request_method:get