我最近将Rails更新为3.1。
这是我添加的部分：
<%= asset_path('logo_symbol.png') %>
这使得/assets/logo_symbol.png在开发环境中完美运行。但是，当我将代码推送到heroku上的生产时，它会显示一个损坏的图像，其中包含url：assets/logo_symbol-135ddc8db2c9b59f032bed7db520137a.png。我猜这个新名字是出于一些优化的原因。
然而有趣的是，当我在制作时转到assets/logo_symbol-135ddc8db2c9b59f032bed7db520137a.png网址时，我看到一个空白页面，但是当我将该网址更改为随机的任何内容时，例如向其中添加数字，它会显示一个页面未找到。很明显，它正在那个网址上找到一些东西。当我直接在production / heroku上转到/assets/logo_symbol.png时，它也会显示一个空白页。
如果这是任何帮助，heroku不会在我推送代码时成功预编译，而heroku的文档说目前没有针对该问题的解决方法。
我们将非常感谢您提供的任何帮助。
我的猜测是它与某些与环境相关的配置有关。我附上了我的application.rb，development.rb和production.rb文件的内容
这是我的production.rb文件的内容
# Settings specified here will take precedence over those in config/application.rb
# In the development environment your application's code is reloaded on
# every request. This slows down response time but is perfect for development
# since you don't have to restart the webserver when you make code changes.
config.cache_classes = false
# Log error messages when you accidentally call methods on nil.
config.whiny_nils = true
# Show full error reports and disable caching
config.consider_all_requests_local = true
config.action_controller.perform_caching = false
# Don't care if the mailer can't send
#config.action_mailer.default_url_options = { :host => 'localhost:3000' }
#config.action_mailer.default_url_options = { :host => 'localhost:3000' }
config.action_mailer.delivery_method = :smtp
# Print deprecation notices to the Rails logger
config.active_support.deprecation = :log
# Only use best-standards-support built into browsers
config.action_dispatch.best_standards_support = :builtin
# Do not compress assets
config.assets.compress = false
# Expands the lines which load the assets
config.assets.debug = true
end
module ActiveAdmin
class Reloader
def attach!
end
end
end
以下是我的development.rb文件的内容
# Settings specified here will take precedence over those in config/application.rb
# In the development environment your application's code is reloaded on
# every request. This slows down response time but is perfect for development
# since you don't have to restart the webserver when you make code changes.
config.cache_classes = false
# Log error messages when you accidentally call methods on nil.
config.whiny_nils = true
# Show full error reports and disable caching
config.consider_all_requests_local = true
config.action_controller.perform_caching = false
# Don't care if the mailer can't send
#config.action_mailer.default_url_options = { :host => 'localhost:3000' }
#config.action_mailer.default_url_options = { :host => 'localhost:3000' }
config.action_mailer.delivery_method = :smtp
# Print deprecation notices to the Rails logger
config.active_support.deprecation = :log
# Only use best-standards-support built into browsers
config.action_dispatch.best_standards_support = :builtin
# Do not compress assets
config.assets.compress = false
# Expands the lines which load the assets
config.assets.debug = true
end
module ActiveAdmin
class Reloader
def attach!
end
end
end
以下是我的production.rb文件的内容
# Settings specified here will take precedence over those in config/application.rb
# The production environment is meant for finished, "live" apps.
# Code is not reloaded between requests
config.cache_classes = true
# Full error reports are disabled and caching is turned on
config.consider_all_requests_local = false
config.action_controller.perform_caching = true
# Specifies the header that your server uses for sending files
config.action_dispatch.x_sendfile_header = "X-Sendfile"
# For nginx:
# config.action_dispatch.x_sendfile_header = 'X-Accel-Redirect'
# If you have no front-end server that supports something like X-Sendfile,
# just comment this out and Rails will serve the files
# See everything in the log (default is :info)
# config.log_level = :debug
# Use a different logger for distributed setups
# config.logger = SyslogLogger.new
# Use a different cache store in production
# config.cache_store = :mem_cache_store
# Disable Rails's static asset server
# In production, Apache or nginx will already do this
config.serve_static_assets = false
# Enable serving of images, stylesheets, and javascripts from an asset server
# config.action_controller.asset_host = "http://assets.example.com"
# Disable delivery errors, bad email addresses will be ignored
# config.action_mailer.raise_delivery_errors = false
#config.action_mailer.default_url_options = { :host => 'ha1.heroku.com' }
config.action_mailer.delivery_method = :smtp
# Enable threaded mode
# config.threadsafe!
# Enable locale fallbacks for I18n (makes lookups for any locale fall back to
# the I18n.default_locale when a translation can not be found)
config.i18n.fallbacks = true
# Send deprecation notices to registered listeners
config.active_support.deprecation = :notify
# Compress JavaScripts and CSS
#config.assets.compress = true
# Don't fallback to assets pipeline if a precompiled asset is missed
config.assets.compile = false
# Generate digests for assets URLs
config.assets.digest = true
# Defaults to Rails.root.join("public/assets")
# config.assets.manifest = YOUR_PATH
config.assets.js_compressor = :uglifier
config.assets.css_compressor = :scss
我将配置文件与3.1的rails文档进行了比较，看起来我已经拥有了所有默认值。但是我仍然没有看到任何形象。任何帮助将不胜感激
答案 0 :(得分：13)
从production.rb中删除此行：
config.action_dispatch.x_sendfile_header = "X-Sendfile"
您还应该将配置文件中的设置与section 9 of the pipeline guides中的设置对齐。
Sendfile标头包含上游Web服务器的信息，用于在何处查找文件（在文件系统上）以便为其提供服务。这将从后端（Rails / Sprockets）中移除负载。当sendfile打开时，HTTP响应中不包含任何正文（它是零长度），这就是为什么你什么都看不见。
在heroku上，nginx服务器无法访问应用程序文件系统，因此无法使用。
请参阅Heroku dev site re sendfile上的this note。
如果您使用的是heroku，this document概述了有效使用管道的最佳选择。
答案 1 :(得分：0)
你需要做两件事来解决它。 首先，在production.rb文件中将这两行从false更改为true。
config.assets.compile = true
config.assets.digest = true
其次，如果你的图像有这样的语法
background: url("imgo.jpg")
将其更改为
background: image-url("image.jpg")
我希望它能完成你的工作。