厨师模板变量@node似乎抛出错误

I'm going through peepcode's Chef tutorial, so far so good. For some reason there is a failure when using template variables. The example is for nginx.

我正在通过peepcode的Chef教程,到目前为止一切顺利。由于某种原因,使用模板变量时出现故障。这个例子是针对nginx的。

In the nginx/attributes/nginx.rb I have:

在nginx / attributes / nginx.rb中我有:

default[:nginx][:worker_processes] = 4

In the nginx.conf.erb template I refer to:

在nginx.conf.erb模板中我指的是:

worker_processes  <%= @node[:nginx][:worker_processes] %>;

Below is the error I get running chef-solo:

以下是我运行chef-solo的错误:

Template Context:
-----------------
on line #2
  1: user www-data;
  2: worker_processes  <%= @node[:nginx][:worker_processes] %>;
  3: 
  4: error_log  /var/log/nginx/error.log;
  5: pid        /var/run/nginx.pid;


[2013-07-14T19:46:36+02:00] ERROR: Running exception handlers
[2013-07-14T19:46:36+02:00] ERROR: Exception handlers complete
Chef Client failed. 0 resources updated
[2013-07-14T19:46:36+02:00] FATAL: Stacktrace dumped to /var/chef/cache/chef-stacktrace.out
[2013-07-14T19:46:36+02:00] FATAL: Chef::Mixin::Template::TemplateError: undefined method `[]' for nil:NilClass

Other part of the error output:

错误输出的其他部分:

Starting Chef Client, version 11.4.4
Compiling Cookbooks...
Converging 3 resources
Recipe: nginx::default
  * package[nginx] action install (up to date)
  * service[nginx] action enable (up to date)
  * service[nginx] action start (up to date)
  * template[/etc/nginx/nginx.conf] action create
================================================================================
Error executing action `create` on resource 'template[/etc/nginx/nginx.conf]'
================================================================================


Chef::Mixin::Template::TemplateError
------------------------------------
undefined method `[]' for nil:NilClass


Resource Declaration:
---------------------
# In /cookbooks/nginx/recipes/default.rb

  8: template "/etc/nginx/nginx.conf" do
  9:    notifies :reload, "service[nginx]"
 10: end



Compiled Resource:
------------------
# Declared in /cookbooks/nginx/recipes/default.rb:8:in `from_file'

template("/etc/nginx/nginx.conf") do
  provider Chef::Provider::Template
  action "create"
  retries 0
  retry_delay 2
  path "/etc/nginx/nginx.conf"
  backup 5
  source "nginx.conf.erb"
  cookbook_name :nginx
  recipe_name "default"
end

2 个解决方案

#1

You can access object variables (the ones that start with @) in templates, only if you passed them through variables method of template like that:

您可以在模板中访问对象变量(以@开头的变量),只有当您通过模板的变量方法传递它们时才会这样:

template("/etc/nginx/nginx.conf") do
  [...]
  variables( :my_var => node )
  [...]
end

Then you will have @my_var available in template. But you don't have to pass the node, because it is already available in templates. You just have to access it not as an object variable. The following code in template should work.

然后你将在模板中提供@my_var。但您不必传递节点,因为它已在模板中可用。您只需要访问它而不是对象变量。模板中的以下代码应该有效。

<%= node[:nginx][:worker_processes] %>

Just remove the @ from the front of node.

只需从节点前面删除@。

#2

The node object is not accessible via an instance variable (the thing starting with an @ sign). Instead, it is a method in the current context.

无法通过实例变量(以@符号开头的东西)访问节点对象。相反,它是当前上下文中的方法。

Change:

<%= @node[:nginx][:worker_processes] %>

<%= node[:nginx][:worker_processes] %>

Notice the removal of the @-sign? You only need the @-sign when passing in variables to the template via the variables parameter.

请注意删除@ -sign?通过变量参数将变量传递给模板时,只需要@ -sign。

#1