similar to: Stale object errors

Hi, IN one of my unit tests I get an ActiveRecord::StaleObjectError: Attempted to update a stale object object.save! in object I have apart from other stuff an after_save method, which calls object.assosication.update_attributes(...) If I remove that line from my code my tests succeeds. Unfortunetly, I do not understand why an update_attributes call can generate an StaleObjectError. Maybe

The error is caused by the save! method updating an object that another thread (most likely in taskomatic) already updated. In the case of this race condition, we retry saving. However, a proper fix would involve fixing the locking. --- src/db-omatic/db_omatic.rb | 23 ++++++++++++++++++++--- 1 files changed, 20 insertions(+), 3 deletions(-) diff --git a/src/db-omatic/db_omatic.rb

Hi All, I''m having some trouble deciding when and how to implement optimistic locking. Let''s say I have a multiuser Rails app, and let''s say it stores, among other things "vital" customer information. The standard methods created by the Rails generate scaffold script look like this: def edit @customer = Customer.find(params[:id]) end

All, I''ve written a simple job/opportunity tracking database app via RoR. I have about 10 internal users. Sometimes 2 people will want to update the same record at more or less the same time and they collide. In particular user 1 may edit a record, then get distracted, and finally an hour later they click save. During that hour user 2 may have pulled up the record, edited it, and

Hi! Say we have a rails active-record-based model called "instance" which can have different states - STOPPED, RUNNING, STARTING_UP, SHUTTING_DOWN, etc... There is a method #start which changes the instance state to STARTING_UP only if it is STOPPED. def start if self.state == STOPPED self.state = STARTING_UP self.save ... end end As you understand if we have multiple

I understand that ActiveRecord supports the "optimistic offline lock"-pattern through magic fields (created_at, updated_at). However, a scaffolded CRUD-Controller doesn''t generate the necessary code to support this feature (the model state gets lost between two action calls). What is the best practice to prevent users from overwriting objects with outdated data ? --

First off, I love mocha and have been using it all over the place ever since I found it a few months ago. So I noticed the other day rather belatedly that mocha-0.4.0 had been released and that we can now do the object.stubs(:method).returns (:first_value, :second_value). Much neater than fiddling with lambdas everytime this sort of behaviour is needed But can we go further ? I was

Hi all I have the following models: class member has_and_belongs_to_many :disc_jockeys end class disc_jockey has_and_belongs_to_many :members end The relation table is called disc_jockeys_members and has the following fields: disc_jockeys_members(disc_jockey_id, member_id, status) So far, the field status can have values like valid, invalid, locked etc., but it is not regarded yet by

Hi all, I''ve searched the forumns, but I can''t seem to find an answer to this one. I''m having trouble getting optimistic locking (OL) to work in my app, even though all of the pieces are there: * table has lock_version column, with default of 0 (zero) * lock_version column is being incremented by the first update (but the second doesn''t catch it) *

Hi, I''m using Rails 2.2.2. I noticed that creating two references to the same database ActiveRecord object, then deleting with one of them, followed by saving with the other, true is returned, but no new record is actually saved. e.g.: doc=Document.new(:title => "sam''s speciality") doc.save doc.id # ==> 23 doc2=Document.find_by_title("sam''s

Hi everyone, I was just trying to catch some exceptions in my app, for "Record Not Found" I used this in my application.rb file rescue_from ActiveRecord::RecordNotFound, :with => :record_not_found rescue_from ActionController::NoMethodError, :with => :show_error private def record_not_found render :text => "404 Not Found", :status =>

My application is going to have a work queue of scheduled tasks stored in the DB. This work queue will be shared across multiple Rails app servers. I need a way to ensure that no two servers get the same jobs if multiple servers pop jobs off the top of the queue simultaneously. Is there a fairly simple way to acheive this? Or do I need to come up with some fancy secondary server to dispatch

I''ve finally managed to find some time to do some serious work on Mocha. There are some code snippets on my blog (http://blog.floehopper.org/articles/2007/04/12/preview-of-latest-mocha-changes) showing the new functionality available in trunk (revision 128). I don''t don''t know how many people out there are using trunk, but it would be great to get some feedback on these

I''m using Rails Recipes to create a login form but instead of username and password, my setup is firstname, lastname, password. I seemed to be gramatically challenged and not sure how to set up the parameter list. Can anyone offer up a suggestion. The book shows the method starting like: if request.post? user = User.find(:first, :conditions => [''username = ?'' ,

My Rails site has a fair amount of login and ''ownership'' logic. For instance, we have a number of clients (companies), each of which has several accounts. A client owns a number of different types of resources, and shouldn''t see any other clients'' resources, so, for example, our ScenesController contains a lot of references to

1st: I am a newbie to Rails & to pure OO. Q: I want to use rails for creating a "master-detail" form. page layout will allow users to type in an "expense report header" and as many "expense report lines" as they need to. I understand how to wrap the final submit action using "transaction" to ensure the inserts to the database happen within the same

Hi, We''re using unicorn as a Rails server on Solaris, and it''s been running great for several months. We''ve recently been having a few problems and I''m at a loss what might cause it. A number of times in the past few days, our unicorn slaves keep timing out & the master keeps restarting them. unicorn.log looks something like : E,

Whenever I tried to start mongrel_rails with the upload progress script, it would die with the following error: /usr/local/lib/ruby/1.8/drb/drb.rb:837:in `getaddrinfo'': getaddrinfo: No address associated with nodename (SocketError) from /usr/local/lib/ruby/1.8/drb/drb.rb:837:in `open_server_inaddr_any'' from /usr/local/lib/ruby/1.8/drb/drb.rb:860:in

Hi Everyone, As many of you out there I''m "protected" by the firewall which prevents me from checking my code for W3C compliance, I am able to check the production code but i would like to test my code before it goes to production. So if anyone was able to have that check done locally, possibly including some sort of tests in to the integration process, I would truly

Some suggestions for R-intro: -------------------------------------------------- Section 9.2.2, change: (Note the function split() which produces a list of vectors obtained by splitting a larger vector according to the classes specified by a factor. This is a useful function, mostly used in connection with boxplots. See the help facility for further details.) Warning: for() loops are used in