CarrierWave 和 RMagick：使用进程 :resize_and_pad 抛出 nil 不是符号错误答案

【问题标题】：CarrierWave and RMagick: Using process :resize_and_pad throwing up nil is not a symbol errorCarrierWave 和 RMagick：使用进程 :resize_and_pad 抛出 nil 不是符号错误
【发布时间】：2012-04-11 05:57:41
【问题描述】：

我创建了一个图片上传器并在其中定义了以下版本

version :profile do
  process :resize_and_pad [100, 100]
end

当我上传文件时，我收到以下错误消息：

nil is not a symbol

查看完整的堆栈跟踪，它来自 processing.rb

carrierwave (0.6.1) lib/carrierwave/uploader/processing.rb:85:in `block in process!'
carrierwave (0.6.1) lib/carrierwave/uploader/processing.rb:81:in `each'
carrierwave (0.6.1) lib/carrierwave/uploader/processing.rb:81:in `process!'
carrierwave (0.6.1) lib/carrierwave/uploader/callbacks.rb:18:in `block in with_callbacks'
carrierwave (0.6.1) lib/carrierwave/uploader/callbacks.rb:18:in `each'
carrierwave (0.6.1) lib/carrierwave/uploader/callbacks.rb:18:in `with_callbacks'
carrierwave (0.6.1) lib/carrierwave/uploader/cache.rb:112:in `cache!'
carrierwave (0.6.1) lib/carrierwave/uploader/versions.rb:230:in `block in cache_versions!'
carrierwave (0.6.1) lib/carrierwave/uploader/versions.rb:216:in `each'
carrierwave (0.6.1) lib/carrierwave/uploader/versions.rb:216:in `cache_versions!'
carrierwave (0.6.1) lib/carrierwave/uploader/callbacks.rb:18:in `block in with_callbacks'
carrierwave (0.6.1) lib/carrierwave/uploader/callbacks.rb:18:in `each'
carrierwave (0.6.1) lib/carrierwave/uploader/callbacks.rb:18:in `with_callbacks'
carrierwave (0.6.1) lib/carrierwave/uploader/cache.rb:112:in `cache!'
carrierwave (0.6.1) lib/carrierwave/uploader/versions.rb:230:in `block in cache_versions!'
carrierwave (0.6.1) lib/carrierwave/uploader/versions.rb:216:in `each'
carrierwave (0.6.1) lib/carrierwave/uploader/versions.rb:216:in `cache_versions!'
carrierwave (0.6.1) lib/carrierwave/uploader/callbacks.rb:18:in `block in with_callbacks'
carrierwave (0.6.1) lib/carrierwave/uploader/callbacks.rb:18:in `each'
carrierwave (0.6.1) lib/carrierwave/uploader/callbacks.rb:18:in `with_callbacks'
carrierwave (0.6.1) lib/carrierwave/uploader/cache.rb:112:in `cache!'
carrierwave (0.6.1) lib/carrierwave/mount.rb:315:in `cache'
carrierwave (0.6.1) lib/carrierwave/mount.rb:173:in `profile_image='
carrierwave (0.6.1) lib/carrierwave/orm/activerecord.rb:37:in `profile_image='
activerecord (3.2.2) lib/active_record/attribute_assignment.rb:85:in `block in assign_attributes'
activerecord (3.2.2) lib/active_record/attribute_assignment.rb:78:in `each'
activerecord (3.2.2) lib/active_record/attribute_assignment.rb:78:in `assign_attributes'
activerecord (3.2.2) lib/active_record/persistence.rb:212:in `block in update_attributes'
activerecord (3.2.2) lib/active_record/transactions.rb:295:in `block in with_transaction_returning_status'
activerecord (3.2.2) lib/active_record/connection_adapters/abstract/database_statements.rb:192:in `transaction'
activerecord (3.2.2) lib/active_record/transactions.rb:208:in `transaction'
activerecord (3.2.2) lib/active_record/transactions.rb:293:in `with_transaction_returning_status'
activerecord (3.2.2) lib/active_record/persistence.rb:211:in `update_attributes'
app/controllers/users_controller.rb:24:in `update_profile'

【问题讨论】：

标签： ruby-on-rails-3 imagemagick carrierwave rmagick

【解决方案1】：

我认为是因为缺少参数，试试

process :resize_and_pad => [120, 120, "blue", "Center"]

【讨论】：

【解决方案2】：

gravityType 不能使用简单的字符串，试试这个：

process :resize_and_pad => [100, 100, "white", Magick::CenterGravity]

http://rmagick.rubyforge.org/src_over.html

【讨论】：

【解决方案3】：

您也可以使用十六进制代码，但您需要 octothorp。

process :resize_and_pad => [1000,1000,"#222222", Magick::CenterGravity]

【讨论】：