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  • Does anyone know how to appropriately deal with user timezones in rails 2.3?

    - by Amazing Jay
    We're building a rails app that needs to display dates (and more importantly, calculate them) in multiple timezones. Can anyone point me towards how to work with user timezones in rails 2.3(.5 or .8) The most inclusive article I've seen detailing how user time zones are supposed to work is here: http://wiki.rubyonrails.org/howtos/time-zones... although it is unclear when this was written or for what version of rails. Specifically it states that: "Time.zone - The time zone that is actually used for display purposes. This may be set manually to override config.time_zone on a per-request basis." Keys terms being "display purposes" and "per-request basis". Locally on my machine, this is true. However on production, neither are true. Setting Time.zone persists past the end of the request (to all subsequent requests) and also affects the way AR saves to the DB (basically treating any date as if it were already in UTC even when its not), thus saving completely inappropriate values. We run Ruby Enterprise Edition on production with passenger. If this is my problem, do we need to switch to JRuby or something else? To illustrate the problem I put the following actions in my ApplicationController right now: def test p_time = Time.now.utc s_time = Time.utc(p_time.year, p_time.month, p_time.day, p_time.hour) logger.error "TIME.ZONE" + Time.zone.inspect logger.error ENV['TZ'].inspect logger.error p_time.inspect logger.error s_time.inspect jl = JunkLead.create! jl.date_at = s_time logger.error s_time.inspect logger.error jl.date_at.inspect jl.save! logger.error s_time.inspect logger.error jl.date_at.inspect render :nothing => true, :status => 200 end def test2 Time.zone = 'Mountain Time (US & Canada)' logger.error "TIME.ZONE" + Time.zone.inspect logger.error ENV['TZ'].inspect render :nothing => true, :status => 200 end def test3 Time.zone = 'UTC' logger.error "TIME.ZONE" + Time.zone.inspect logger.error ENV['TZ'].inspect render :nothing => true, :status => 200 end and they yield the following: Processing ApplicationController#test (for 98.202.196.203 at 2010-12-24 22:15:50) [GET] TIME.ZONE#<ActiveSupport::TimeZone:0x2c57a68 @tzinfo=#<TZInfo::DataTimezone: Etc/UTC>, @name="UTC", @utc_offset=0> nil Fri Dec 24 22:15:50 UTC 2010 Fri Dec 24 22:00:00 UTC 2010 Fri Dec 24 22:00:00 UTC 2010 Fri, 24 Dec 2010 22:00:00 UTC +00:00 Fri Dec 24 22:00:00 UTC 2010 Fri, 24 Dec 2010 22:00:00 UTC +00:00 Completed in 21ms (View: 0, DB: 4) | 200 OK [http://www.dealsthatmatter.com/test] Processing ApplicationController#test2 (for 98.202.196.203 at 2010-12-24 22:15:53) [GET] TIME.ZONE#<ActiveSupport::TimeZone:0x2c580a8 @tzinfo=#<TZInfo::DataTimezone: America/Denver>, @name="Mountain Time (US & Canada)", @utc_offset=-25200> nil Completed in 143ms (View: 1, DB: 3) | 200 OK [http://www.dealsthatmatter.com/test2] Processing ApplicationController#test (for 98.202.196.203 at 2010-12-24 22:15:59) [GET] TIME.ZONE#<ActiveSupport::TimeZone:0x2c580a8 @tzinfo=#<TZInfo::DataTimezone: America/Denver>, @name="Mountain Time (US & Canada)", @utc_offset=-25200> nil Fri Dec 24 22:15:59 UTC 2010 Fri Dec 24 22:00:00 UTC 2010 Fri Dec 24 22:00:00 UTC 2010 Fri, 24 Dec 2010 15:00:00 MST -07:00 Fri Dec 24 22:00:00 UTC 2010 Fri, 24 Dec 2010 15:00:00 MST -07:00 Completed in 20ms (View: 0, DB: 4) | 200 OK [http://www.dealsthatmatter.com/test] Processing ApplicationController#test3 (for 98.202.196.203 at 2010-12-24 22:16:03) [GET] TIME.ZONE#<ActiveSupport::TimeZone:0x2c57a68 @tzinfo=#<TZInfo::DataTimezone: Etc/UTC>, @name="UTC", @utc_offset=0> nil Completed in 17ms (View: 0, DB: 2) | 200 OK [http://www.dealsthatmatter.com/test3] Processing ApplicationController#test (for 98.202.196.203 at 2010-12-24 22:16:04) [GET] TIME.ZONE#<ActiveSupport::TimeZone:0x2c57a68 @tzinfo=#<TZInfo::DataTimezone: Etc/UTC>, @name="UTC", @utc_offset=0> nil Fri Dec 24 22:16:05 UTC 2010 Fri Dec 24 22:00:00 UTC 2010 Fri Dec 24 22:00:00 UTC 2010 Fri, 24 Dec 2010 22:00:00 UTC +00:00 Fri Dec 24 22:00:00 UTC 2010 Fri, 24 Dec 2010 22:00:00 UTC +00:00 Completed in 151ms (View: 0, DB: 4) | 200 OK [http://www.dealsthatmatter.com/test] It should be clear above that the 2nd call to /test shows Time.zone set to Mountain, even though it shouldn't. Additionally, checking the database reveals that the test action when run after test2 saved a JunkLead record with a date of 2010-12-22 15:00:00, which is clearly wrong.

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  • Uninitialized constant Item::Types

    - by Rasmus
    Hi! First of, im a newbie ruby programmer so please bare with me if this is a very dumb question. I get this uninitialized constant error when i submit my nested forms. order.rb class Order < ActiveRecord::Base has_many :items, :dependent => :destroy has_many :types, :through => :items accepts_nested_attributes_for :items accepts_nested_attributes_for :types validates_associated :items validates_associated :types end item.rb class Item < ActiveRecord::Base has_one :types belongs_to :order accepts_nested_attributes_for :types validates_associated :types end type.rb class Type < ActiveRecord::Base belongs_to :items belongs_to :orders end new.erb.html <% form_for @order do |f| %> <%= f.error_messages %> <% f.fields_for :items do |builder| %> <table border="0"> <th>Type</th> <th>Amount</th> <th>Text</th> <th>Price</th> <tr> <% f.fields_for :type do |m| %> <td> <%= m.collection_select :type, Type.find(:all, :order => "created_at DESC"), :id, :name, {:prompt => "Select a Type" }, {:id => "selector", :onchange => "type_change(this)"} %> </td> <% end %> <td> <%= f.text_field :amount, :id => "amountField", :onchange => "change_total_price()" %> </td> <td> <%= f.text_field :text, :id => "textField" %> </td> <td> <%= f.text_field :price, :class => "priceField", :onChange => "change_total_price()" %> </td> <td> <%= link_to_remove_fields "Remove Item", f %> </td> </tr> </table> <% end %> <p><%= link_to_add_fields "Add Item", f, :items %></p> <p> <%= f.label :total_price %><br /> <%= f.text_field :total_price, :class => "priceField", :id => "totalPrice" %> </p> <p><%= f.submit "Create"%></p> <% end %> <%= link_to 'Back', orders_path %> create method in orders_controller.rb def create @order = Order.new(params[:order]) respond_to do |format| if @order.save flash[:notice] = 'Post was successfully created.' format.html { redirect_to(@order) } format.xml { render :xml => @order, :status => :created, :location => @order } else format.html { render :action => "new" } format.xml { render :xml => @order.errors, :status => :unprocessable_entity } end end end Hopefully you can see what i cant

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  • Rails routing to XML/JSON without views gone mad

    - by John Schulze
    I have a mystifying problem. In a very simple Ruby app i have three classes: Drivers, Jobs and Vehicles. All three classes only consist of Id and Name. All three classes have the same #index and #show methods and only render in JSON or XML (this is in fact true for all their CRUD methods, they are identical in everything but name). There are no views. For example: def index @drivers= Driver.all respond_to do |format| format.js { render :json => @drivers} format.xml { render :xml => @drivers} end end def show @driver = Driver.find(params[:id]) respond_to do |format| format.js { render :json => @driver} format.xml { render :xml => @driver} end end The models are similarly minimalistic and only contain: class Driver< ActiveRecord::Base validates_presence_of :name end In routes.rb I have: map.resources :drivers map.resources :jobs map.resources :vehicles map.connect ':controller/:action/:id' map.connect ':controller/:action/:id.:format' I can perform POST/create, GET/index and PUT/update on all three classes and GET/read used to work as well until I installed the "has many polymorphs" ActiveRecord plugin and added to environment.rb: require File.join(File.dirname(__FILE__), 'boot') require 'has_many_polymorphs' require 'active_support' Now for two of the three classes I cannot do a read any more. If i go to localhost:3000/drivers they all list nicely in XML but if i go to localhost:3000/drivers/3 I get an error: Processing DriversController#show (for 127.0.0.1 at 2009-06-11 20:34:03) [GET] Parameters: {"id"=>"3"} [4;36;1mDriver Load (0.0ms)[0m [0;1mSELECT * FROM "drivers" WHERE ("drivers"."id" = 3) [0m ActionView::MissingTemplate (Missing template drivers/show.erb in view path app/views): app/controllers/drivers_controller.rb:14:in `show' ...etc This is followed a by another unexpected error: Processing ApplicationController#show (for 127.0.0.1 at 2009-06-11 21:35:52)[GET] Parameters: {"id"=>"3"} NameError (uninitialized constant ApplicationController::AreaAccessDenied): ...etc What is going on here? Why does the same code work for one class but not the other two? Why is it trying to do a #view on the ApplicationController? I found that if I create a simple HTML view for each of the three classes these work fine. To each class I add: format.html # show.html.erb With this in place, going to localhost:3000/drivers/3 renders out the item in HTML and I get no errors in the log. But if attach .xml to the URL it again fails for two of the classes (with the same error message as before) while one will output XML as expected. Even stranger, on the two failing classes, when adding .js to the URL (to trigger JSON rendering) I get the HTML output instead! Is it possible this has something to do with the "has many polymorphs" plugin? I have heard of people having routing issues after installing it. Removing "has many polymorphs" and "active support" from environment.rb (and rebooting the sever) seems to make no difference whatsoever. Yet my problems started after it was installed. I've spent a number of hours on this problem now and am starting to get a little desperate, Google turns up virtually no information which makes me suspect I must have missed something elementary. Any enlightenment or hint gratefully received! JS

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  • Custom validation works in development but not in unit test

    - by Geolev
    I want to validate that at least one of two columns have a value in my model. I found somewhere on the web that I could create a custom validator as follows: # Check for the presence of one or another field: # :validates_presence_of_at_least_one_field :last_name, :company_name - would require either last_name or company_name to be filled in # also works with arrays # :validates_presence_of_at_least_one_field :email, [:name, :address, :city, :state] - would require email or a mailing type address module ActiveRecord module Validations module ClassMethods def validates_presence_of_at_least_one_field(*attr_names) msg = attr_names.collect {|a| a.is_a?(Array) ? " ( #{a.join(", ")} ) " : a.to_s}.join(", ") + "can't all be blank. At least one field must be filled in." configuration = { :on => :save, :message => msg } configuration.update(attr_names.extract_options!) send(validation_method(configuration[:on]), configuration) do |record| found = false attr_names.each do |a| a = [a] unless a.is_a?(Array) found = true a.each do |attr| value = record.respond_to?(attr.to_s) ? record.send(attr.to_s) : record[attr.to_s] found = !value.blank? end break if found end record.errors.add_to_base(configuration[:message]) unless found end end end end end I put this in a file called lib/acs_validator.rb in my project and added "require 'acs_validator'" to my environment.rb. This does exactly what I want. It works perfectly when I manually test it in the development environment but when I write a unit test it breaks my test environment. This is my unit test: require 'test_helper' class CustomerTest < ActiveSupport::TestCase # Replace this with your real tests. test "the truth" do assert true end test "customer not valid" do puts "customer not valid" customer = Customer.new assert !customer.valid? assert customer.errors.invalid?(:subdomain) assert_equal "Company Name and Last Name can't both be blank.", customer.errors.on(:contact_lname) end end This is my model: class Customer < ActiveRecord::Base validates_presence_of :subdomain validates_presence_of_at_least_one_field :customer_company_name, :contact_lname, :message => "Company Name and Last Name can't both be blank." has_one :service_plan end When I run the unit test, I get the following error: DEPRECATION WARNING: Rake tasks in vendor/plugins/admin_data/tasks, vendor/plugins/admin_data/tasks, and vendor/plugins/admin_data/tasks are deprecated. Use lib/tasks instead. (called from /usr/lib/ruby/gems/1.8/gems/rails-2.3.8/lib/tasks/rails.rb:10) Couldn't drop acs_test : #<ActiveRecord::StatementInvalid: PGError: ERROR: database "acs_test" is being accessed by other users DETAIL: There are 1 other session(s) using the database. : DROP DATABASE IF EXISTS "acs_test"> acs_test already exists NOTICE: CREATE TABLE will create implicit sequence "customers_id_seq" for serial column "customers.id" NOTICE: CREATE TABLE / PRIMARY KEY will create implicit index "customers_pkey" for table "customers" NOTICE: CREATE TABLE will create implicit sequence "service_plans_id_seq" for serial column "service_plans.id" NOTICE: CREATE TABLE / PRIMARY KEY will create implicit index "service_plans_pkey" for table "service_plans" /usr/bin/ruby1.8 -I"lib:test" "/usr/lib/ruby/gems/1.8/gems/rake-0.8.7/lib/rake/rake_test_loader.rb" "test/unit/customer_test.rb" "test/unit/service_plan_test.rb" "test/unit/helpers/dashboard_helper_test.rb" "test/unit/helpers/customers_helper_test.rb" "test/unit/helpers/service_plans_helper_test.rb" /usr/lib/ruby/gems/1.8/gems/activerecord-2.3.8/lib/active_record/base.rb:1994:in `method_missing_without_paginate': undefined method `validates_presence_of_at_least_one_field' for #<Class:0xb7076bd0> (NoMethodError) from /usr/lib/ruby/gems/1.8/gems/will_paginate-2.3.12/lib/will_paginate/finder.rb:170:in `method_missing' from /home/george/projects/advancedcomfortcs/app/models/customer.rb:3 from /usr/local/lib/site_ruby/1.8/rubygems/custom_require.rb:31:in `gem_original_require' from /usr/local/lib/site_ruby/1.8/rubygems/custom_require.rb:31:in `require' from /usr/lib/ruby/gems/1.8/gems/activesupport-2.3.8/lib/active_support/dependencies.rb:158:in `require' from /usr/lib/ruby/gems/1.8/gems/activesupport-2.3.8/lib/active_support/dependencies.rb:265:in `require_or_load' from /usr/lib/ruby/gems/1.8/gems/activesupport-2.3.8/lib/active_support/dependencies.rb:224:in `depend_on' from /usr/lib/ruby/gems/1.8/gems/activesupport-2.3.8/lib/active_support/dependencies.rb:136:in `require_dependency' from /usr/lib/ruby/gems/1.8/gems/rails-2.3.8/lib/initializer.rb:414:in `load_application_classes' from /usr/lib/ruby/gems/1.8/gems/rails-2.3.8/lib/initializer.rb:413:in `each' from /usr/lib/ruby/gems/1.8/gems/rails-2.3.8/lib/initializer.rb:413:in `load_application_classes' from /usr/lib/ruby/gems/1.8/gems/rails-2.3.8/lib/initializer.rb:411:in `each' from /usr/lib/ruby/gems/1.8/gems/rails-2.3.8/lib/initializer.rb:411:in `load_application_classes' from /usr/lib/ruby/gems/1.8/gems/rails-2.3.8/lib/initializer.rb:197:in `process' from /usr/lib/ruby/gems/1.8/gems/rails-2.3.8/lib/initializer.rb:113:in `send' from /usr/lib/ruby/gems/1.8/gems/rails-2.3.8/lib/initializer.rb:113:in `run' from /home/george/projects/advancedcomfortcs/config/environment.rb:9 from ./test/test_helper.rb:2:in `require' from ./test/test_helper.rb:2 from ./test/unit/customer_test.rb:1:in `require' from ./test/unit/customer_test.rb:1 from /usr/lib/ruby/gems/1.8/gems/rake-0.8.7/lib/rake/rake_test_loader.rb:5:in `load' from /usr/lib/ruby/gems/1.8/gems/rake-0.8.7/lib/rake/rake_test_loader.rb:5 from /usr/lib/ruby/gems/1.8/gems/rake-0.8.7/lib/rake/rake_test_loader.rb:5:in `each' from /usr/lib/ruby/gems/1.8/gems/rake-0.8.7/lib/rake/rake_test_loader.rb:5 rake aborted! Command failed with status (1): [/usr/bin/ruby1.8 -I"lib:test" "/usr/lib/ru...] (See full trace by running task with --trace) It seems to have stepped on will_paginate somehow. Does anyone have any suggestions? Is there another way to do the validation I'm attempting to do? Thanks, George

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  • Is it possible to call Javascript's onsubmit event programatically on a form?

    - by hoyhoy
    In Ruby on Rails, I'm attempting to update the innerHTML of a div tag using the form_remote_tag helper. This update happens whenever an associated select tag receives an onchange event. The problem is, <select onchange="this.form.submit();">; doesn't work. Nor does document.forms[0].submit(). The only way to get the onsubmit code generated in the form_remote_tag to execute is to create a hidden submit button, and invoke the click method on the button from the select tag. Here's a working ERb partial example. <% form_remote_tag :url => product_path, :update => 'content', :method => 'get' do -%> <% content_tag :div, :id => 'content' do -%> <%= select_tag :update, options_for_select([["foo", 1], ["bar", 2]]), :onchange => "this.form.commit.click" %> <%= submit_tag 'submit_button', :style => "display: none" %> <% end %> <% end %> What I want to do is something like this, but it doesn't work. <% form_remote_tag :url => product_path, :update => 'content', :method => 'get' do -%> <% content_tag :div, :id => 'content' do -%> # the following line does not work <%= select_tag :update, options_for_select([["foo", 1], ["bar", 2]]), :onchange => "this.form.onsubmit()" %> <% end %> <% end %> So, is there any way to remove the invisible submit button for this use case? There seems to be some confusion. So, let me explain. The basic problem is that submit() doesn't call the onsubmit() code rendered into the form. The actual HTML form that Rails renders from this ERb looks like this: <form action="/products/1" method="post" onsubmit="new Ajax.Updater('content', '/products/1', {asynchronous:true, evalScripts:true, method:'get', parameters:Form.serialize(this)}); return false;"> <div style="margin:0;padding:0"> <input name="authenticity_token" type="hidden" value="4eacf78eb87e9262a0b631a8a6e417e9a5957cab" /> </div> <div id="content"> <select id="update" name="update" onchange="this.form.commit.click"> <option value="1">foo</option> <option value="2">bar</option> </select> <input name="commit" style="display: none" type="submit" value="submit_button" /> </div> </form> I want to axe the invisible submit button, but using a straight form.submit appears to not work. So, I need some way to call the form's onsubmit event code. Update: Orion Edwards solution would work if there wasn't a return(false); generated by Rails. I'm not sure which is worse though, sending a phantom click to an invisible submit button or calling eval on the getAttribute('onsubmit') call after removing the return call with a javascript string replacement!

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  • Problem with migrating a model in ruby

    - by Shreyas Satish
    I run script/generate model query edit query.rb in models.. class Query < ActiveRecord::Base #I even tried Migrations instead of Base def sef.up create table :queries do|t| t.string :name end end def self.down drop_table :queries end end ,run rake db:migrate. and what I see in db is this: mysql> desc queries; +------------+----------+------+-----+---------+----------------+ | Field | Type | Null | Key | Default | Extra | +------------+----------+------+-----+---------+----------------+ | id | int(11) | NO | PRI | NULL | auto_increment | | created_at | datetime | YES | | NULL | | | updated_at | datetime | YES | | NULL | | +------------+----------+------+-----+---------+----------------+ Where is the "name" field? HELP ! Cheers !

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  • Rails "rake test" crashing

    - by Homer J. Simpson
    Hi, this might be rather unspecific, but I'm trying to do 'rake test' on a new rails app, and end up with (in /Users/myname/dev/railstest/RailsApplication1) /System/Library/Frameworks/Ruby.framework/Versions/1.8/usr/bin/ruby -I"lib:test" "/Library/Ruby/Gems/1.8/gems/rake-0.8.7/lib/rake/rake_test_loader.rb" /System/Library/Frameworks/Ruby.framework/Versions/1.8/usr/bin/ruby -I"lib:test" "/Library/Ruby/Gems/1.8/gems/rake-0.8.7/lib/rake/rake_test_loader.rb" /System/Library/Frameworks/Ruby.framework/Versions/1.8/usr/bin/ruby -I"lib:test" "/Library/Ruby/Gems/1.8/gems/rake-0.8.7/lib/rake/rake_test_loader.rb" No other output. System is Leopard 10.5, Rails 2.3.5, Ruby 1.86 Any ideas ?

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  • IP address numbers in MySQL subquery

    - by Iain Collins
    I have a problem with a subquery involving IPV4 addresses stored in MySQL (MySQL 5.0). The IP addresses are stored in two tables, both in network number format - e.g. the format output by MySQL's INET_ATON(). The first table ('events') contains lots of rows with IP addresses associated with them, the second table ('network_providers') contains a list of provider information for given netblocks. events table (~4,000,000 rows): event_id (int) event_name (varchar) ip_address (unsigned 4 byte int) network_providers table (~60,000 rows): ip_start (unsigned 4 byte int) ip_end (unsigned 4 byte int) provider_name (varchar) Simplified for the purposes of the problem I'm having, the goal is to create an export along the lines of: event_id,event_name,ip_address,provider_name If do a query along the lines of either of the following, I get the result I expect: SELECT provider_name FROM network_providers WHERE INET_ATON('192.168.0.1') >= network_providers.ip_start ORDER BY network_providers.ip_start DESC LIMIT 1 SELECT provider_name FROM network_providers WHERE 3232235521 >= network_providers.ip_start ORDER BY network_providers.ip_start DESC LIMIT 1 That is to say, it returns the correct provider_name for whatever IP I look up (of course I'm not really using 192.168.0.1 in my queries). However, when performing this same query as a subquery, in the following manner, it doesn't yield the result I would expect: SELECT event.id, event.event_name, (SELECT provider_name FROM network_providers WHERE event.ip_address >= network_providers.ip_start ORDER BY network_providers.ip_start DESC LIMIT 1) as provider FROM events Instead the a different (incorrect) value for network_provider is returned - over 90% (but curiously not all) values returned in the provider column contain the wrong provider information for that IP. Using event.ip_address in a subquery just to echo out the value confirms it contains the value I'd expect and that the subquery can parse it. Replacing event.ip_address with an actual network number also works, just using it dynamically in the subquery in this manner that doesn't work for me. I suspect the problem is there is something fundamental and important about subqueries in MySQL that I don't get. I've worked with IP addresses like this in MySQL quite a bit before, but haven't previously done lookups for them using a subquery. The question: I'd really appreciate an example of how I could get the output I want, and if someone here knows, some enlightenment as to why what I'm doing doesn't work so I can avoid making this mistake again. Notes: The actual real-world usage I'm trying to do is considerably more complicated (involving joining two or three tables). This is a simplified version, to avoid overly complicating the question. Additionally, I know I'm not using a between on ip_start & ip_end - that's intentional (the DB's can be out of date, and such cases the owner in the DB is almost always in the next specified range and 'best guess' is fine in this context) however I'm grateful for any suggestions for improvement that relate to the question. Efficiency is always nice, but in this case absolutely not essential - any help appreciated.

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  • launchctl - use rvm instead of system Ruby in executed scripts?

    - by Stefan Kendall
    I have a launchctl job I define as such: <key>ProgramArguments</key> <array> <string>/bin/sh</string> <string>-c</string> <string>~/projects/script.sh</string> </array> When I run script.sh manually, the script works fine, as it uses the currently configured rvm version of ruby. When I run this through launchctl, the system version of Ruby is used, which breaks the script. How can I get this script to run with the right version of ruby available?

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  • Does the order of columns in a query matter?

    - by James Simpson
    When selecting columns from a MySQL table, is performance affected by the order that you select the columns as compared to their order in the table (not considering indexes that may cover the columns)? For example, you have a table with rows uid, name, bday, and you have the following query. SELECT uid, name, bday FROM table Does MySQL see the following query any differently and thus cause any sort of performance hit? SELECT uid, bday, name FROM table

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  • Values of generated column not appearing in table

    - by msh210
    I'm using mysql version 5.1.41-3ubuntu12.10 (Ubuntu). mysql> show create table tt\G *************************** 1. row *************************** Table: tt Create Table: CREATE TABLE `tt` ( `pz` int(8) DEFAULT NULL, `os` varchar(8) DEFAULT NULL, `uz` int(11) NOT NULL, `p` bigint(21) NOT NULL DEFAULT '0', `c` decimal(23,0) DEFAULT NULL, KEY `pz` (`pz`), KEY `uz` (`uz`), KEY `os` (`os`), KEY `pz_2` (`pz`,`uz`) ) ENGINE=MyISAM DEFAULT CHARSET=latin1 1 row in set (0.00 sec) mysql> select pz,uz,pz*uz, -> if(pz*uz,1,.5), -> left(pz,2) pl,left(lpad(uz,5,0),2) ul, -> p from tt limit 10; +-------+----+-------+----------------+--------+----+--------+ | pz | uz | pz*uz | if(pz*uz,1,.5) | pl | ul | p | +-------+----+-------+----------------+--------+----+--------+ | NULL | 0 | NULL | 0.5 | NULL | 00 | 4080 | | NULL | 0 | NULL | 0.5 | NULL | 00 | 323754 | | 89101 | 0 | 0 | 0.5 | 89 | 00 | 6880 | | 0 | 0 | 0 | 0.5 | 0 | 00 | 11591 | | 89110 | 0 | 0 | 0.5 | 89 | 00 | 72 | | 78247 | 0 | 0 | 0.5 | 78 | 00 | 27 | | 90062 | 0 | 0 | 0.5 | 90 | 00 | 5 | | 63107 | 0 | 0 | 0.5 | 63 | 00 | 4 | | NULL | 0 | NULL | 0.5 | NULL | 00 | 54561 | | 94102 | 0 | 0 | 0.5 | 94 | 00 | 12499 | +-------+----+-------+----------------+--------+----+--------+ So far so good. As you see, 0.5 appears as a value of if(pz*uz,1,.5). The problem is: mysql> select os, -> if(pz*uz,left(pz,2)<=>left(lpad(uz,5,0),2),.5) uptwo, -> if(pz*uz,left(pz,3)<=>left(lpad(uz,5,0),3),.5) upthree, -> sum(p) p,sum(c) c -> from tt t -> group by os,uptwo,upthree order by null; +----+-------+---------+---------+-------+ | os | uptwo | upthree | p | c | +----+-------+---------+---------+-------+ | u | 1 | 1 | 52852 | 318 | | i | 1 | 1 | 7046563 | 21716 | | m | 1 | 1 | 1252166 | 7337 | | i | 0 | 0 | 1830284 | 4033 | | m | 0 | 0 | 294612 | 1714 | | i | 1 | 0 | 911486 | 3560 | | m | 1 | 0 | 145182 | 1136 | | u | 0 | 0 | 12144 | 23 | | u | 1 | 0 | 1571 | 8 | +----+-------+---------+---------+-------+ Although I group by uptwo, 0.5 doesn't appear in that column. What happened to the 0.5 values? Edit: As noted in the comments to Todd Gibson's answer, I also tried it with if(pz*uz,cast(left(pz,2)<=>left(lpad(uz,5,0),2) as decimal),.5) instead of if(pz*uz,left(pz,2)<=>left(lpad(uz,5,0),2),.5), but it, too, didn't work.

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  • Ruby - model.rb:20: syntax error, unexpected keyword_end, expecting $end

    - by Yasir Adnan
    I don't understand what's wrong with my code. model.rb require 'Gemfile' DataMapper.setup(:default, 'mysql://root:password@localhost/rengine') Class User include DataMapper::Resource property :id, Serial # An auto-increment integer key property :email, String, format: :email_address property :username, String, required: true property :password, String , length: 10..255, required: true property :created_at, DateTime property :updated_at, DateTime #User can have mutiple posts has n, :posts end Class Post include DataMapper::Resource property :id, Serial # An auto-increment integer key property :title, String, required: true property :body, Text, required: true property :created_at, DateTime property :updated_at, DateTime #Posts belongs to a USer belongs_to :user end DataMapper.auto_upgrade! I didn't able to figure out. What's problem is here??

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  • Ruby on Rails - Working with times

    - by miligraf
    If in a database (MySQL), I have a datetime column (ex. 1899-12-30 19:00:00), how do I sum 1 day to it? Following http://corelib.rubyonrails.org/classes/Time.html#M000240 If I want to add 1 day, it actually adds 60*60*24 days (86,400 days) r=Record.find(:first) =>Sat, 30 Dec 1899 19:00:00 -0600 r.date + (60*60*24) =>Fri, 20 Jul 2136 19:00:00 -0600 But if I do this it actually adds 1 day: t = Time.now =>Mon Jun 14 10:32:51 -0600 2010 t + (60 * 60 * 24) =>Tue Jun 15 10:33:21 -0600 2010 I guess it has to do with the format...how do I make this work?

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  • Rails Active Record find(:all, :order => ) issue.

    - by CodingWithoutComments
    I seem to be unable to use :order_by for more than one column at a time. For example, I have a "Show" model with date and attending columns. If I run the following code: @shows = Show.find(:all, :order => "date") I get the following results: [#<Show id: 7, date: "2009-04-18", attending: 2>, #<Show id: 1, date: "2009-04-18", attending: 78>, #<Show id: 2, date: "2009-04-19", attending: 91>, #<Show id: 3, date: "2009-04-20", attending: 16>, #<Show id: 4, date: "2009-04-21", attending: 136>] If I run the following code: @shows = Show.find(:all, :order => "attending DESC") [#<Show id: 4, date: "2009-04-21", attending: 136>, #<Show id: 2, date: "2009-04-19", attending: 91>, #<Show id: 1, date: "2009-04-18", attending: 78>, #<Show id: 3, date: "2009-04-20", attending: 16>, #<Show id: 7, date: "2009-04-18", attending: 2>] But, if I run: @shows = Show.find(:all, :order => "date, attending DESC") OR @shows = Show.find(:all, :order => "date, attending ASC") OR @shows = Show.find(:all, :order => "date ASC, attending DESC") I get the same results as only sorting by date: [#<Show id: 7, date: "2009-04-18", attending: 2>, #<Show id: 1, date: "2009-04-18", attending: 78>, #<Show id: 2, date: "2009-04-19", attending: 91>, #<Show id: 3, date: "2009-04-20", attending: 16>, #<Show id: 4, date: "2009-04-21", attending: 136>] Where as, I want to get these results: [#<Show id: 1, date: "2009-04-18", attending: 78>, #<Show id: 7, date: "2009-04-18", attending: 2>, #<Show id: 2, date: "2009-04-19", attending: 91>, #<Show id: 3, date: "2009-04-20", attending: 16>, #<Show id: 4, date: "2009-04-21", attending: 136>] This is the query being generated from the logs: [4;35;1mUser Load (0.6ms)[0m [0mSELECT * FROM "users" WHERE ("users"."id" = 1) LIMIT 1[0m [4;36;1mShow Load (3.0ms)[0m [0;1mSELECT * FROM "shows" ORDER BY date ASC, attending DESC[0m [4;35;1mUser Load (0.6ms)[0m [0mSELECT * FROM "users" WHERE ("users"."id" = 1) [0m Finally, here is my model: create_table "shows", :force => true do |t| t.string "headliner" t.string "openers" t.string "venue" t.date "date" t.text "description" t.datetime "created_at" t.datetime "updated_at" t.decimal "price" t.time "showtime" t.integer "attending", :default => 0 t.string "time" end What am I missing? What am I doing wrong? UPDATE: Thanks for all your help, but it seems that all of you were stumped as much as I was. What solved the problem was actually switching databases. I switched from the default sqlite3 to mysql.

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  • Language Prejudices

    - by paranoid_pedlar
    I've been researching programming languages, in hopes of learning to program. Since I've heard a lot of good things about Ruby, I went ahead and purchased The Pragmatic guide to Ruby. I understand that there is a lot of hype about Ruby on Rails. Because ruby lets you program scripts, applications, and internet helped me to decide on learning Ruby vs other languages. Today I watched a talk about google go, and it's really caught my attention. Coincidently I stumbled on a talk about jruby. I've been under the impression that java applications are bloated an slow. However the speaker made a point of what is wrong with Ruby, and how Jruby diagnosed Ruby's shortcomings. All that said. I would like to hear peoples opinions on Jruby vs Ruby, and if Ruby is working on fixing these "short comings". Also, how do you, the programming community feel about "go" and if I'm making a mistake learning Ruby instead of go, or Jruby. Appreciate your advice and opinions Thanks,

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  • MySQL 5.5 (Percona) assertion failure log.. what would cause this?

    - by Tom Geee
    256GB, 64 Core , AMD running Ubuntu 12.04 with Percona MySQL 5.5.28. Below is the assertion failure. We just had a second assertion failure (different "in file", position, etc) while running a large set of inserts. After the first failure, MySQL restarted after a reboot only - after continuously looping on the same error after trying to recover. I decided to do a mysqlcheck with -o for optimize. Since these are all Innodb tables (very large tables, 60+GB) this would do an alter table on all tables. In the middle of this , the below assertion failure happened again: 121115 22:30:31 InnoDB: Assertion failure in thread 140086589445888 in file btr0pcur.c line 452 InnoDB: Failing assertion: btr_page_get_prev(next_page, mtr) == buf_block_get_page_no(btr_pcur_get_block(cursor)) InnoDB: We intentionally generate a memory trap. InnoDB: Submit a detailed bug report to http://bugs.mysql.com. InnoDB: If you get repeated assertion failures or crashes, even InnoDB: immediately after the mysqld startup, there may be InnoDB: corruption in the InnoDB tablespace. Please refer to InnoDB: http://dev.mysql.com/doc/refman/5.5/en/forcing-innodb-recovery.html InnoDB: about forcing recovery. 03:30:31 UTC - mysqld got signal 6 ; This could be because you hit a bug. It is also possible that this binary or one of the libraries it was linked against is corrupt, improperly built, or misconfigured. This error can also be caused by malfunctioning hardware. We will try our best to scrape up some info that will hopefully help diagnose the problem, but since we have already crashed, something is definitely wrong and this may fail. Please help us make Percona Server better by reporting any bugs at http://bugs.percona.com/ key_buffer_size=536870912 read_buffer_size=131072 max_used_connections=404 max_threads=500 thread_count=90 connection_count=90 It is possible that mysqld could use up to key_buffer_size + (read_buffer_size + sort_buffer_size)*max_threads = 1618416 K bytes of memory Hope that's ok; if not, decrease some variables in the equation. Thread pointer: 0x14edeb710 Attempting backtrace. You can use the following information to find out where mysqld died. If you see no messages after this, something went terribly wrong... stack_bottom = 7f687366ce80 thread_stack 0x30000 /usr/sbin/mysqld(my_print_stacktrace+0x2e)[0x7b52ee] /usr/sbin/mysqld(handle_fatal_signal+0x484)[0x68f024] /lib/x86_64-linux-gnu/libpthread.so.0(+0xfcb0)[0x7f9cbb23fcb0] /lib/x86_64-linux-gnu/libc.so.6(gsignal+0x35)[0x7f9cbaea6425] /lib/x86_64-linux-gnu/libc.so.6(abort+0x17b)[0x7f9cbaea9b8b] /usr/sbin/mysqld[0x858463] /usr/sbin/mysqld[0x804513] /usr/sbin/mysqld[0x808432] /usr/sbin/mysqld[0x7db8bf] /usr/sbin/mysqld(_Z13rr_sequentialP11READ_RECORD+0x1d)[0x755aed] /usr/sbin/mysqld(_Z17mysql_alter_tableP3THDPcS1_P24st_ha_create_informationP10TABLE_LISTP10Alter_infojP8st_orderb+0x216b)[0x60399b] /usr/sbin/mysqld(_Z20mysql_recreate_tableP3THDP10TABLE_LIST+0x166)[0x604bd6] /usr/sbin/mysqld[0x647da1] /usr/sbin/mysqld(_ZN24Optimize_table_statement7executeEP3THD+0xde)[0x64891e] /usr/sbin/mysqld(_Z21mysql_execute_commandP3THD+0x1168)[0x59b558] /usr/sbin/mysqld(_Z11mysql_parseP3THDPcjP12Parser_state+0x30c)[0x5a132c] /usr/sbin/mysqld(_Z16dispatch_command19enum_server_commandP3THDPcj+0x1620)[0x5a2a00] /usr/sbin/mysqld(_Z24do_handle_one_connectionP3THD+0x14f)[0x63ce6f] /usr/sbin/mysqld(handle_one_connection+0x51)[0x63cf31] /lib/x86_64-linux-gnu/libpthread.so.0(+0x7e9a)[0x7f9cbb237e9a] /lib/x86_64-linux-gnu/libc.so.6(clone+0x6d)[0x7f9cbaf63cbd] Trying to get some variables. Some pointers may be invalid and cause the dump to abort. Query (7f6300004b60): is an invalid pointer Connection ID (thread ID): 876 Status: NOT_KILLED You may download the Percona Server operations manual by visiting http://www.percona.com/software/percona-server/. You may find information in the manual which will help you identify the cause of the crash. 121115 22:31:07 [Note] Plugin 'FEDERATED' is disabled. 121115 22:31:07 InnoDB: The InnoDB memory heap is disabled 121115 22:31:07 InnoDB: Mutexes and rw_locks use GCC atomic builtins .. Then it recovered , without a reboot this time. from the log, what would cause this? I am currently running a dump to see if the problem resurfaces. edit: data partition is all in / since this is a hosted, defaulted file system unfortunately: Filesystem Size Used Avail Use% Mounted on /dev/vda3 742G 445G 260G 64% / udev 121G 4.0K 121G 1% /dev tmpfs 49G 248K 49G 1% /run none 5.0M 0 5.0M 0% /run/lock none 121G 0 121G 0% /run/shm /dev/vda1 99M 54M 40M 58% /boot my.cnf: [client] port = 3306 socket = /var/run/mysqld/mysqld.sock [mysqld_safe] socket = /var/run/mysqld/mysqld.sock nice = 0 [mysqld] skip-name-resolve innodb_file_per_table default_storage_engine=InnoDB user = mysql socket = /var/run/mysqld/mysqld.sock port = 3306 basedir = /usr datadir = /data/mysql tmpdir = /tmp skip-external-locking key_buffer = 512M max_allowed_packet = 128M thread_stack = 192K thread_cache_size = 64 myisam-recover = BACKUP max_connections = 500 table_cache = 812 table_definition_cache = 812 #query_cache_limit = 4M #query_cache_size = 512M join_buffer_size = 512K innodb_additional_mem_pool_size = 20M innodb_buffer_pool_size = 196G #innodb_file_io_threads = 4 #innodb_thread_concurrency = 12 innodb_flush_log_at_trx_commit = 1 innodb_log_buffer_size = 8M innodb_log_file_size = 1024M innodb_log_files_in_group = 2 innodb_max_dirty_pages_pct = 90 innodb_lock_wait_timeout = 120 log_error = /var/log/mysql/error.log long_query_time = 5 slow_query_log = 1 slow_query_log_file = /var/log/mysql/slowlog.log [mysqldump] quick quote-names max_allowed_packet = 16M [mysql] [isamchk] key_buffer = 16M

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  • WebSocket handshake with Ruby and EM::WebSocket::Server

    - by Chad Johnson
    I am trying to create a simple WebSocket connection in JavaScript against my Rails app. I get the following: WebSocket connection to 'ws://localhost:4000/' failed: Error during WebSocket handshake: 'Sec-WebSocket-Accept' header is missing What am I doing wrong? Here is my code: JavaScript: var socket = new WebSocket('ws://localhost:4000'); socket.onopen = function() { var handshake = "GET / HTTP/1.1\n" + "Host: localhost\n" + "Upgrade: websocket\n" + "Connection: Upgrade\n" + "Sec-WebSocket-Key: x3JJHMbDL1EzLkh9GBhXDw==\n" + "Sec-WebSocket-Protocol: quote\n" + "Sec-WebSocket-Version: 13\n" + "Origin: http://localhost\n"; socket.send(handshake); }; socket.onmessage = function(data) { console.log(data); }; Ruby: require 'rubygems' require 'em-websocket-server' module QuoteService class WebSocket < EventMachine::WebSocket::Server def on_connect handshake_response = "HTTP/1.1 101 Switching Protocols\n" handshake_response << "Upgrade: websocket\n" handshake_response << "Connection: Upgrade\n" handshake_response << "Sec-WebSocket-Accept: HSmrc0sMlYUkAGmm5OPpG2HaGWk=\n" handshake_response << "Sec-WebSocket-Protocol: quote\n" send_message(handshake_response) end def on_receive(data) puts 'RECEIVED: ' + data end end end EventMachine.run do print 'Starting WebSocket server...' EventMachine.start_server '0.0.0.0', 4000, QuoteService::WebSocket puts 'running' end The handshake headers are per Wikipedia.

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  • How to parse SOAP response from ruby client?

    - by Richard O'Neil
    Hi I am learning Ruby and I have written the following code to find out how to consume SOAP services: require 'soap/wsdlDriver' wsdl="http://www.abundanttech.com/webservices/deadoralive/deadoralive.wsdl" service=SOAP::WSDLDriverFactory.new(wsdl).create_rpc_driver weather=service.getTodaysBirthdays('1/26/2010') The response that I get back is: #<SOAP::Mapping::Object:0x80ac3714 {http://www.abundanttech.com/webservices/deadoralive} getTodaysBirthdaysResult=#<SOAP::Mapping::Object:0x80ac34a8 {http://www.w3.org/2001/XMLSchema}schema=#<SOAP::Mapping::Object:0x80ac3214 {http://www.w3.org/2001/XMLSchema}element=#<SOAP::Mapping::Object:0x80ac2f6c {http://www.w3.org/2001/XMLSchema}complexType=#<SOAP::Mapping::Object:0x80ac2cc4 {http://www.w3.org/2001/XMLSchema}choice=#<SOAP::Mapping::Object:0x80ac2a1c {http://www.w3.org/2001/XMLSchema}element=#<SOAP::Mapping::Object:0x80ac2774 {http://www.w3.org/2001/XMLSchema}complexType=#<SOAP::Mapping::Object:0x80ac24cc {http://www.w3.org/2001/XMLSchema}sequence=#<SOAP::Mapping::Object:0x80ac2224 {http://www.w3.org/2001/XMLSchema}element=[#<SOAP::Mapping::Object:0x80ac1f7c>, #<SOAP::Mapping::Object:0x80ac13ec>, #<SOAP::Mapping::Object:0x80ac0a28>, #<SOAP::Mapping::Object:0x80ac0078>, #<SOAP::Mapping::Object:0x80abf6c8>, #<SOAP::Mapping::Object:0x80abed18>] >>>>>>> {urn:schemas-microsoft-com:xml-diffgram-v1}diffgram=#<SOAP::Mapping::Object:0x80abe6c4 {}NewDataSet=#<SOAP::Mapping::Object:0x80ac1220 {}Table=[#<SOAP::Mapping::Object:0x80ac75e4 {}FullName="Cully, Zara" {}BirthDate="01/26/1892" {}DeathDate="02/28/1979" {}Age="(87)" {}KnownFor="The Jeffersons" {}DeadOrAlive="Dead">, #<SOAP::Mapping::Object:0x80b778f4 {}FullName="Feiffer, Jules" {}BirthDate="01/26/1929" {}DeathDate=#<SOAP::Mapping::Object:0x80c7eaf4> {}Age="81" {}KnownFor="Cartoonists" {}DeadOrAlive="Alive">]>>>> I am having a great deal of difficulty figuring out how to parse and show the returned information in a nice table, or even just how to loop through the records and have access to each element (ie. FullName,Age,etc). I went through the whole "getTodaysBirthdaysResult.methods - Object.new.methods" and kept working down to try and work out how to access the elements, but then I get to the array and I got lost. Any help that can be offered would be appreciated.

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  • Jquery html grab + calling a controller action using javascript (ruby on rails)

    - by Zind
    Preface: I consider myself "slightly effective" in ruby on rails, and a complete novice in javascript. Also, yes, I have installed jQuery and associated plugins instead of the default Prototype library. I am in a situation where I am pulling in a table from off-site in an iframe (which is taking care of all internal JS for me) such that when a part of the table is clicked, a td will gain the class "active." What I would like to do is take this info (I'm assuming I can get it in a string format), and pass it to a method (in my controller, I'm assuming) which will parse the html, pull out the pertinent info, and then call a creation method in the same controller with the parsed info, the end result being a new item in that table. What I have so far is javascript which I believe is correct so far: <script type="text/javascript"> var ImportInfo = function() { var info = $('td.active').html(); // call controller action which parses the given string, //checks for existence in database, and adds new row if needed } $("#Import").click(ImportInfo); </script> and, of course, a button with id="ImportLocation." I have looked at this question: http://stackoverflow.com/questions/1334447/using-jquery-to-call-a-controller-action but am somewhat unsure as to how to call a controller action to pass the contents of the td as a string. Is this doable with the jQuery post method?

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  • Ruby metaclass madness

    - by t6d
    I'm stuck. I'm trying to dynamically define a class method and I can't wrap my head around the ruby metaclass model. Consider the following class: class Example def self.meta; (class << self; self; end); end def self.class_instance; self; end end Example.class_instance.class # => Class Example.meta.class # => Class Example.class_instance == Example # => true Example.class_instance == Example.meta # => false Obviously both methods return an instance of Class. But these two instances are not the same. They also have different ancestors: Example.meta.ancestors # => [Class, Module, Object, Kernel] Example.class_instance.ancestors # => [Example, Object, Kernel] Whats the point in making a difference between the metaclass and the class instance? I figured out, that I can send :define_method to the metaclass to dynamically define a method, but if I try to send it to the class instance it won't work. At least I could solve my problem, but I still want to understand why it is working this way.

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  • Ruby: add custom properties to built-in classes

    - by dreftymac
    Question: Using Ruby it is simple to add custom methods to existing classes, but how do you add custom properties? Here is an example of what I am trying to do: myarray = Array.new(); myarray.concat([1,2,3]); myarray._meta_ = Hash.new(); # obviously, this wont work myarray._meta_['createdby'] = 'dreftymac'; myarray._meta_['lastupdate'] = '1993-12-12'; ## desired result puts myarray._meta_['createdby']; #=> 'dreftymac' puts myarray.inspect() #=> [1,2,3] The goal is to construct the class definition in such a way that the stuff that does not work in the example above will work as expected. Update: (clarify question) One aspect that was left out of the original question: it is also a goal to add "default values" that would ordinarily be set-up in the initialize method of the class. Update: (why do this) Normally, it is very simple to just create a custom class that inherits from Array (or whatever built-in class you want to emulate). This question derives from some "testing-only" code and is not an attempt to ignore this generally acceptable approach.

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  • Ruby: add custom properties to built-in classes

    - by dreftymac
    Question: Using Ruby it is simple to add custom methods to existing classes, but how do you add custom properties? Here is an example of what I am trying to do: myarray = Array.new(); myarray.concat([1,2,3]); myarray._meta_ = Hash.new(); # obviously, this wont work myarray._meta_['createdby'] = 'dreftymac'; myarray._meta_['lastupdate'] = '1993-12-12'; ## desired result puts myarray._meta_['createdby']; #=> 'dreftymac' puts myarray.inspect() #=> [1,2,3] The goal is to construct the class definition in such a way that the stuff that does not work in the example above will work as expected. Update: (clarify question) One aspect that was left out of the original question: it is also a goal to add "default values" that would ordinarily be set-up in the initialize method of the class. Update: (why do this) Normally, it is very simple to just create a custom class that inherits from Array (or whatever built-in class you want to emulate). This question derives from some "testing-only" code and is not an attempt to ignore this generally acceptable approach.

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  • Getting Argument Names In Ruby Reflection

    - by Joe Soul-bringer
    I would like to do some fairly heavy-duty reflection in the Ruby programming language. I would like to create a function which would return the names of the arguments of various calling functions higher up the call stack (just one higher would be enough but why stop there?). I could use Kernel.caller go to the file and parse the argument list but that would be ugly and unreliable. The function that I would like would work in the following way: module A def method1( tuti, fruity) foo end def method2(bim, bam, boom) foo end def foo print caller_args[1].join(",") #the "1" mean one step up the call stack end end A.method1 #prints "tuti,fruity" A.method2 #prints "bim, bam, boom" I would not mind using ParseTree or some similar tool for this task but looking at Parsetree, it is not obvious how to use it for this purpose. Creating a C extension like this is another possibility but it would be nice if someone had already done it for me. Edit2: I can see that I'll probably need some kind of C extension. I suppose that means my question is what combination of C extension would work most easily. I don't think caller+ParseTree would be enough by themselves. As far as why I would like to do this goes, rather than saying "automatic debugging", perhaps I should say that I would like to use this functionality to do automatic checking of the calling and return conditions of functions. Say def add x, y check_positive return x + y end Where check_positive would throw an exception if x and y weren't positive (obviously, there would be more to it than that but hopefully this gives enough motivation)

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