耙db：填充错误：未定义的方法file_changed

Question

这是我的耙任务文件：

namespace  :db do
    desc "fill database with sample data"
    task :populate => :environment do

     puts "populating with sample data"

     make_users

     make_companies

     make_products

     make_images

     make_commits

    end
    end


    def make_users

        100.times do |user|

           User.create!(first_name: Faker::Name.first_name,
                        last_name: Faker::Name.last_name,
                        email: Faker::Internet.email,
                            question_response: "ques"+(user).to_s,
                            device_id: 100,
                            company_name:"somecompany"+(user).to_s)
        end
    end


    def make_companies

         100.times do |company|

               name = Faker::Name.first_name
               rep_name = "example"+(company).to_s
               rep_designation = "example_desig"+(company).to_s
               company_large_logo = "example_lg"+(company).to_s
               company_small_logo ="example_sg"+(company).to_s
               company_social_contacts = "example_csc"+(company).to_s
               company_writeup = "example_wr"+(company).to_s
               website = "exampleCompany"+(company).to_s
               rep_image = "example_image"+(company).to_s
               active = 1
               average = 10


               Company.create!(name: name,
                               rep_name: rep_name,
                               rep_designation: rep_designation,
                               company_social_contacts: company_social_contacts,
                               company_large_logo: company_large_logo,
                               company_small_logo: company_small_logo,
                               company_writeup: company_writeup,
                               website:website,
                               rep_image: rep_image,
                               active:active,
                               average: average)
          end
    end


    def make_products


        companies=Company.all

        100.times do |product|  


            name = Faker::Name.name
                image_url = "some_image_url"+(product+1).to_s
            description = "some_description"+(product+1).to_s
            website = "some_website"+(product+1).to_s
            active = 0
            unlocked_time = "time"+(product+1).to_s
            company_id = companies.sample.id
            #aggregate = product+10


            companies.sample.products.create!(name: name,
                                              image_url: image_url,
                                              description: description,
                                                  website: website,
                                                  active: active,
                                                  unlocked_time: unlocked_time,
                                                  company_id: company_id,
                                                  aggregate: 0)  
        end
    end


    def make_commits
        users = User.all
        products = Product.all

        100.times do |commit|

                user_selected=users.sample
                product_selected=products.sample

                user_selected.commits.create!(product_id: product_selected.id,
                                                                  user_id: user_selected.id,
                                                                  estimate: commit*2,
                                                                  commit: commit+1)
        end
    end


    def make_images

        products = Product.all

        100.times do |image|
                products.sample.images.create!(product_id: products.sample.id,
                                                                           file: "sample_image#{image+1}")
        end
    end

当我运行rake db:populate时，出现此堆栈跟踪错误。 我怎样才能解决这个问题？

堆栈跟踪：

     populating with sample data
    rake aborted!
    undefined method `file_changed?' for #<Product:0x0000010493e6f8>
    /Users/test/.rvm/gems/ruby-1.9.3-p362/gems/activemodel-3.2.11/lib/active_model/attribute_methods.rb:407:in `method_missing'
    /Users/test/.rvm/gems/ruby-1.9.3-p362/gems/activerecord-3.2.11/lib/active_record/attribute_methods.rb:149:in `method_missing'
    /Users/test/.rvm/gems/ruby-1.9.3-p362/gems/carrierwave-0.8.0/lib/carrierwave/mount.rb:249:in `store_previous_model_for_file'
    /Users/test/.rvm/gems/ruby-1.9.3-p362/gems/activesupport-3.2.11/lib/active_support/callbacks.rb:407:in `_run__4010438894236454661__update__1959316297081505070__callbacks'
    /Users/test/.rvm/gems/ruby-1.9.3-p362/gems/activesupport-3.2.11/lib/active_support/callbacks.rb:405:in `__run_callback'
    /Users/test/.rvm/gems/ruby-1.9.3-p362/gems/activesupport-3.2.11/lib/active_support/callbacks.rb:385:in `_run_update_callbacks'
    /Users/test/.rvm/gems/ruby-1.9.3-p362/gems/activesupport-3.2.11/lib/active_support/callbacks.rb:81:in `run_callbacks'
    /Users/test/.rvm/gems/ruby-1.9.3-p362/gems/activerecord-3.2.11/lib/active_record/callbacks.rb:272:in `update'
    /Users/test/.rvm/gems/ruby-1.9.3-p362/gems/activerecord-3.2.11/lib/active_record/persistence.rb:348:in `create_or_update'
    /Users/test/.rvm/gems/ruby-1.9.3-p362/gems/activerecord-3.2.11/lib/active_record/callbacks.rb:264:in `block in create_or_update'
    /Users/test/.rvm/gems/ruby-1.9.3-p362/gems/activesupport-3.2.11/lib/active_support/callbacks.rb:436:in `_run__4010438894236454661__save__1959316297081505070__callbacks'
    /Users/test/.rvm/gems/ruby-1.9.3-p362/gems/activesupport-3.2.11/lib/active_support/callbacks.rb:405:in `__run_callback'
    /Users/test/.rvm/gems/ruby-1.9.3-p362/gems/activesupport-3.2.11/lib/active_support/callbacks.rb:385:in `_run_save_callbacks'
    /Users/test/.rvm/gems/ruby-1.9.3-p362/gems/activesupport-3.2.11/lib/active_support/callbacks.rb:81:in `run_callbacks'
    /Users/test/.rvm/gems/ruby-1.9.3-p362/gems/activerecord-3.2.11/lib/active_record/callbacks.rb:264:in `create_or_update'
    /Users/test/.rvm/gems/ruby-1.9.3-p362/gems/activerecord-3.2.11/lib/active_record/persistence.rb:84:in `save'
    /Users/test/.rvm/gems/ruby-1.9.3-p362/gems/activerecord-3.2.11/lib/active_record/validations.rb:50:in `save'
    /Users/test/.rvm/gems/ruby-1.9.3-p362/gems/activerecord-3.2.11/lib/active_record/attribute_methods/dirty.rb:22:in `save'
    /Users/test/.rvm/gems/ruby-1.9.3-p362/gems/activerecord-3.2.11/lib/active_record/transactions.rb:259:in `block (2 levels) in save'
    /Users/test/.rvm/gems/ruby-1.9.3-p362/gems/activerecord-3.2.11/lib/active_record/transactions.rb:313:in `block in with_transaction_returning_status'
    /Users/test/.rvm/gems/ruby-1.9.3-p362/gems/activerecord-3.2.11/lib/active_record/connection_adapters/abstract/database_statements.rb:192:in `transaction'
    /Users/test/.rvm/gems/ruby-1.9.3-p362/gems/activerecord-3.2.11/lib/active_record/transactions.rb:208:in `transaction'
    /Users/test/.rvm/gems/ruby-1.9.3-p362/gems/activerecord-3.2.11/lib/active_record/transactions.rb:311:in `with_transaction_returning_status'
    /Users/test/.rvm/gems/ruby-1.9.3-p362/gems/activerecord-3.2.11/lib/active_record/transactions.rb:259:in `block in save'
    /Users/test/.rvm/gems/ruby-1.9.3-p362/gems/activerecord-3.2.11/lib/active_record/transactions.rb:270:in `rollback_active_record_state!'
    /Users/test/.rvm/gems/ruby-1.9.3-p362/gems/activerecord-3.2.11/lib/active_record/transactions.rb:258:in `save'
    /Users/test/.rvm/gems/ruby-1.9.3-p362/gems/activerecord-3.2.11/lib/active_record/persistence.rb:217:in `block in update_attributes'
    /Users/test/.rvm/gems/ruby-1.9.3-p362/gems/activerecord-3.2.11/lib/active_record/transactions.rb:313:in `block in with_transaction_returning_status'
    /Users/test/.rvm/gems/ruby-1.9.3-p362/gems/activerecord-3.2.11/lib/active_record/connection_adapters/abstract/database_statements.rb:192:in `transaction'
    /Users/test/.rvm/gems/ruby-1.9.3-p362/gems/activerecord-3.2.11/lib/active_record/transactions.rb:208:in `transaction'
    /Users/test/.rvm/gems/ruby-1.9.3-p362/gems/activerecord-3.2.11/lib/active_record/transactions.rb:311:in `with_transaction_returning_status'
    /Users/test/.rvm/gems/ruby-1.9.3-p362/gems/activerecord-3.2.11/lib/active_record/persistence.rb:215:in `update_attributes'
    /Users/test/Launch/launch/app/models/product.rb:61:in `aggregate_more'
    /Users/test/Launch/launch/app/models/commit.rb:30:in `aggregate_commit'
    /Users/test/.rvm/gems/ruby-1.9.3-p362/gems/activesupport-3.2.11/lib/active_support/callbacks.rb:427:in `_run__2272083058160445442__save__1959316297081505070__callbacks'
    /Users/test/.rvm/gems/ruby-1.9.3-p362/gems/activesupport-3.2.11/lib/active_support/callbacks.rb:405:in `__run_callback'
    /Users/test/.rvm/gems/ruby-1.9.3-p362/gems/activesupport-3.2.11/lib/active_support/callbacks.rb:385:in `_run_save_callbacks'
    /Users/test/.rvm/gems/ruby-1.9.3-p362/gems/activesupport-3.2.11/lib/active_support/callbacks.rb:81:in `run_callbacks'
    /Users/test/.rvm/gems/ruby-1.9.3-p362/gems/activerecord-3.2.11/lib/active_record/callbacks.rb:264:in `create_or_update'
    /Users/test/.rvm/gems/ruby-1.9.3-p362/gems/activerecord-3.2.11/lib/active_record/persistence.rb:104:in `save!'
    /Users/test/.rvm/gems/ruby-1.9.3-p362/gems/activerecord-3.2.11/lib/active_record/validations.rb:56:in `save!'
    /Users/test/.rvm/gems/ruby-1.9.3-p362/gems/activerecord-3.2.11/lib/active_record/attribute_methods/dirty.rb:33:in `save!'
    /Users/test/.rvm/gems/ruby-1.9.3-p362/gems/activerecord-3.2.11/lib/active_record/transactions.rb:264:in `block in save!'
    /Users/test/.rvm/gems/ruby-1.9.3-p362/gems/activerecord-3.2.11/lib/active_record/transactions.rb:313:in `block in with_transaction_returning_status'
    /Users/test/.rvm/gems/ruby-1.9.3-p362/gems/activerecord-3.2.11/lib/active_record/connection_adapters/abstract/database_statements.rb:192:in `transaction'
    /Users/test/.rvm/gems/ruby-1.9.3-p362/gems/activerecord-3.2.11/lib/active_record/transactions.rb:208:in `transaction'
    /Users/test/.rvm/gems/ruby-1.9.3-p362/gems/activerecord-3.2.11/lib/active_record/transactions.rb:311:in `with_transaction_returning_status'
    /Users/test/.rvm/gems/ruby-1.9.3-p362/gems/activerecord-3.2.11/lib/active_record/transactions.rb:264:in `save!'
    /Users/test/.rvm/gems/ruby-1.9.3-p362/gems/activerecord-3.2.11/lib/active_record/associations/has_many_association.rb:14:in `insert_record'
    /Users/test/.rvm/gems/ruby-1.9.3-p362/gems/activerecord-3.2.11/lib/active_record/associations/collection_association.rb:436:in `block (2 levels) in create_record'
    /Users/test/.rvm/gems/ruby-1.9.3-p362/gems/activerecord-3.2.11/lib/active_record/associations/collection_association.rb:344:in `add_to_target'
    /Users/test/.rvm/gems/ruby-1.9.3-p362/gems/activerecord-3.2.11/lib/active_record/associations/collection_association.rb:434:in `block in create_record'
    /Users/test/.rvm/gems/ruby-1.9.3-p362/gems/activerecord-3.2.11/lib/active_record/associations/collection_association.rb:149:in `block in transaction'
    /Users/test/.rvm/gems/ruby-1.9.3-p362/gems/activerecord-3.2.11/lib/active_record/connection_adapters/abstract/database_statements.rb:192:in `transaction'
    /Users/test/.rvm/gems/ruby-1.9.3-p362/gems/activerecord-3.2.11/lib/active_record/transactions.rb:208:in `transaction'
    /Users/test/.rvm/gems/ruby-1.9.3-p362/gems/activerecord-3.2.11/lib/active_record/associations/collection_association.rb:148:in `transaction'
    /Users/test/.rvm/gems/ruby-1.9.3-p362/gems/activerecord-3.2.11/lib/active_record/associations/collection_association.rb:433:in `create_record'
    /Users/test/.rvm/gems/ruby-1.9.3-p362/gems/activerecord-3.2.11/lib/active_record/associations/collection_association.rb:123:in `create!'
    /Users/test/.rvm/gems/ruby-1.9.3-p362/gems/activerecord-3.2.11/lib/active_record/associations/collection_proxy.rb:46:in `create!'
    /Users/test/Launch/launch/lib/tasks/sample_data.rake:107:in `block in make_commits'
    /Users/test/Launch/launch/lib/tasks/sample_data.rake:102:in `times'
    /Users/test/Launch/launch/lib/tasks/sample_data.rake:102:in `make_commits'
    /Users/test/Launch/launch/lib/tasks/sample_data.rake:16:in `block (2 levels)
    /Users/test/.rvm/gems/ruby-1.9.3-p362/bin/ruby_noexec_wrapper:14:in `eval'
    /Users/test/.rvm/gems/ruby-1.9.3-p362/bin/ruby_noexec_wrapper:14:in main
    Tasks: TOP => db:populate
    (See full trace by running task with --trace)

我还使用载波宝来上传图像。

Answer 1

经过一些调试后，我设法通过了此错误。 您需要进行迁移以添加一个字段，该字段由mount_uploader 。 例如：

class Product
  mount_uploader :my_image
end

需要迁移：

add_column：products，：my_image，：string

公平地说，这是在载波的自述文件中。 希望能帮助到你 ：）