activerecord

问题 I pull a record as: def self.imp_broadcast_preview! Broadcast.where(for_gamers: true).order(:created_at).last end And then in my controller I have: def index @conversations = Conversation.where(gamer: @gamer) @conversations << Broadcast.imp_broadcast_preview! end The above code works properly in Rails 4.2 and merges the last broadcast message in the conversations. I just updated my codebase to Rails 5.2 and now I am getting an error: NoMethodError (undefined method `<<' for #<Conversation:

问题 I have a simple scoping question. I would like to do this as a scope: if article.responses.blank? return false elsif article.responses.last.passed.eql?(false) return true else return false end So on the article model I would have something like this: scope :failed_response, { :joins=>[:responses], :conditions=>["responses.passed = ?", false] } The problem is, I only want instances where the most recent response failed. I'm sure these is a way to do this with either fancy sorting or some kind

问题 I have a Listing model which has_many :categories, through: :categories_listings and has_many :categories_listings . I was testing it with a Factory Girl factory which looks like this: factory :listing do |f| f.sequence (:title) { |n| "Listing #{n}" } message {Faker::Lorem.paragraph} cards {[FactoryGirl.create(:card)]} categories {[FactoryGirl.create(:category)]} association :delivery_condition association :unit_of_measure quantity 1 unit_price 1 end And everything was OK until I added the

问题 I try to figure out how I can localize the error item name in my rails application which appear when a user sign's up with uncorrect datas... I figured out how to override the messages but not the names of the messages like ("password", "login", "email", ...) de: activerecord: errors: models: user: attributes: password_confirmation: blank: "" password: confirmation: "" blank: "" too_short: "" login: taken: "" blank: "" too_short: "" email: taken: "" blank: "" too_short: "" invalid: ""

问题 I have a test for uniqueness which works: it { should validate_uniqueness_of(:name).case_insensitive } however when I try to do a similar test for name it fails it { should validate_presence_of(:name).allow_blank } I get this error: undefined method allow_blank'` 回答1: According to this list, there's no method in shoulda that can be chained to validate_presence_of that would support what you want to do. Have a look at the source code of the matcher here. However, there is another matcher you

问题 So I'm parsing data from twitter api in rails using the twitter library, and sometimes the response from api might be like this: { error: "Invalid parameter" } And the model will raise an exception, right now I'm silently catch it and put the error.message into the log, how do I pass this exception to the controller so I can display it on the view? Thanks. UPDATE: The error is likely to happen because I'm allowing my customer to build queries, and they might put advanced queries like "https:/

问题 So I'm parsing data from twitter api in rails using the twitter library, and sometimes the response from api might be like this: { error: "Invalid parameter" } And the model will raise an exception, right now I'm silently catch it and put the error.message into the log, how do I pass this exception to the controller so I can display it on the view? Thanks. UPDATE: The error is likely to happen because I'm allowing my customer to build queries, and they might put advanced queries like "https:/

问题 I'm trying to use ActiveRecord's find_or_create_by_*column* , but I'm getting errors from Postgres letting me know that it occasionally fails to find the model, and tries to insert one anyways. It's really important that I keep this table unique, so I added a :unique => true attribute to its migration, so that Postgres would know that I was serious about it. And, fail: ActiveRecord::StatementInvalid: PGError: ERROR: duplicate key value violates unique constraint "index_marketo_leads_on_person

问题 I'm trying to use ActiveRecord's find_or_create_by_*column* , but I'm getting errors from Postgres letting me know that it occasionally fails to find the model, and tries to insert one anyways. It's really important that I keep this table unique, so I added a :unique => true attribute to its migration, so that Postgres would know that I was serious about it. And, fail: ActiveRecord::StatementInvalid: PGError: ERROR: duplicate key value violates unique constraint "index_marketo_leads_on_person

问题 I am using ActiveRecord with Rails 3. I defined scopes in my model. How can I get the list of all scopes of that model? Previously I could use Model.scopes OR Can I check a scope is defined or not? Something like Model.scope_defined?("scope_name") Thanks in advance. 回答1: You can see if a scope is defined or not this way Model.send(:valid_scope_name?, :scope_name) it will return true if it does exist and nil if it does not. If you check the source code of valid_scope_name?, you see that you