breakpoint Resource
This page is generated from the Chef Infra Client source code.To suggest a change, edit the breakpoint.rb file and submit a pull request to the Chef Infra Client repository.
Use the breakpoint resource to add breakpoints to recipes. Run the chef-shell in Chef Infra Client mode, and then use those breakpoints to debug recipes. Breakpoints are ignored by the chef-client during an actual chef-client run. That said, breakpoints are typically used to debug recipes only when running them in a non-production environment, after which they are removed from those recipes before the parent cookbook is uploaded to the Chef server.
New in Chef Infra Client 12.0.
Syntax
The full syntax for all of the properties that are available to the breakpoint resource is:
breakpoint 'name' do
action Symbol # defaults to :break if not specified
end
where:
breakpoint
is the resource.name
is the name given to the resource block.action
identifies which steps Chef Infra Client will take to bring the node into the desired state.
Actions
The breakpoint resource has the following actions:
:break
- Add a breakpoint for use with chef-shell (default)
:nothing
- This resource block doesn’t act unless notified by another resource to take action. Once notified, this resource block either runs immediately or is queued up to run at the end of a Chef Infra Client run.
Properties
This resource does not have any properties.
Debug Recipes with chef-shell
chef-shell is a recipe debugging tool that allows the use of breakpoints within recipes. chef-shell runs as an Interactive Ruby (IRb) session. chef-shell supports both recipe and attribute file syntax, as well as interactive debugging features.Modes
chef-shell is tool that’s run using an Interactive Ruby (IRb) session. chef-shell currently supports recipe and attribute file syntax, as well as interactive debugging features. chef-shell has three run modes:
Mode | Description |
---|---|
Standalone | Default. No cookbooks are loaded, and the run-list is empty. |
Solo | chef-shell acts as a Chef Solo Client. It attempts to load the chef-solo configuration file at ~/.chef/config.rb and any JSON attributes passed. If the JSON attributes set a run-list, it will be honored. Cookbooks will be loaded in the same way that chef-solo loads them. chef-solo mode is activated with the -s or --solo command line option, and JSON attributes are specified in the same way as for chef-solo, with -j /path/to/chef-solo.json . |
Client | chef-shell acts as a Chef Infra Client. During startup, it reads the Chef Infra Client configuration file from ~/.chef/client.rb and contacts the Chef Infra Server to get the node's run_list, attributes, and cookbooks. Chef Infra Client mode is activated with the -z or --client options. You can also specify the configuration file with -c CONFIG and the server URL with -S SERVER_URL . |
Configure
chef-shell determines which configuration file to load based on the following:
- If a configuration file is specified using the
-c
option, chef-shell will use the specified configuration file - If a NAMED_CONF is given, chef-shell will load ~/.chef/NAMED_CONF/chef_shell.rb
- If no NAMED_CONF is given chef-shell will load ~/.chef/chef_shell.rb if it exists
- If no chef_shell.rb can be found, chef-shell falls back to load:
- /etc/chef/client.rb if -z option is given.
- /etc/chef/solo.rb if –solo-legacy-mode option is given.
- .chef/config.rb if -s option is given.
- .chef/knife.rb if -s option is given.
chef-shell.rb
The chef-shell.rb file can be used to configure chef-shell in the same
way as the client.rb file is used to configure Chef Infra Client. For
example, to configure chef-shell to authenticate to the Chef Infra
Server, copy the node_name
, client_key
, and chef_server_url
settings from the config.rb file:
node_name 'your-knife-clientname'
client_key File.expand_path('~/.chef/my-client.pem')
chef_server_url 'https://api.opscode.com/organizations/myorg'
and then add them to the chef-shell.rb file. Other configuration possibilities include disabling Ohai plugins (which will speed up the chef-shell boot process) or including arbitrary Ruby code in the chef-shell.rb file.
Run as a Chef Infra Client
By default, chef-shell loads in standalone mode and doesn’t connect to the Chef Infra Server. The chef-shell can be run as a Chef Infra Client to verify functionality that’s only available when Chef Infra Client connects to the Chef Infra Server, such as search functionality or accessing data stored in data bags.
chef-shell can use the same credentials as knife when connecting to a
Chef Infra Server. Make sure that the settings in chef-shell.rb are the
same as those in config.rb, and then use the -z
option as part of the
command. For example:
chef-shell -z
Manage
When chef-shell is configured to access a Chef Infra Server, chef-shell can list, show, search for and edit cookbooks, clients, nodes, roles, environments, policyfiles, and data bags.
The syntax for managing objects on the Chef Infra Server is as follows:
chef-shell -z named_configuration
Where:
named_configuration
is an existing configuration file in~/.chef/named_configuration/chef_shell.rb
, such asproduction
,staging
, ortest
.
Once in chef-shell, commands can be run against objects as follows:
chef (preprod) > items.command
Where:
items
is the type of item to search for:cookbooks
,clients
,nodes
,roles
,environments
or a data bag.command
is the command:list
,show
,find
, oredit
.
For example, to list all of the nodes in a configuration named “preprod”, enter:
chef (preprod) > nodes.list
Which will return something similar to:
=> [node[i-f09a939b], node[i-049a936f], node[i-eaaaa581], node[i-9154b1fb],
node[i-6a213101], node[i-c2687aa9], node[i-7abeaa11], node[i-4eb8ac25],
node[i-9a2030f1], node[i-a06875cb], node[i-145f457f], node[i-e032398b],
node[i-dc8c98b7], node[i-6afdf401], node[i-f49b119c], node[i-5abfab31],
node[i-78b8ac13], node[i-d99678b3], node[i-02322269], node[i-feb4a695],
node[i-9e2232f5], node[i-6e213105], node[i-cdde3ba7], node[i-e8bfb083],
node[i-743c2c1f], node[i-2eaca345], node[i-aa7f74c1], node[i-72fdf419],
node[i-140e1e7f], node[i-f9d43193], node[i-bd2dc8d7], node[i-8e7f70e5],
node[i-78f2e213], node[i-962232fd], node[i-4c322227], node[i-922232f9],
node[i-c02728ab], node[i-f06c7b9b]]
The list
command can take a code block, which will applied (but not
saved), to each object that’s returned from the server. For example:
chef (preprod) > nodes.list {|n| puts "#{n.name}: #{n.run_list}" }
will return something similar to:
=> i-f09a939b: role[lb], role[preprod], recipe[aws]
i-049a936f: role[lb], role[preprod], recipe[aws]
i-9154b1fb: recipe[erlang], role[base], role[couchdb], role[preprod],
i-6a213101: role[chef], role[preprod]
# more...
The show
command can be used to display a specific node. For example:
chef (preprod) > load_balancer = nodes.show('i-f09a939b')
will return something similar to:
=> node[i-f09a939b]
Or:
chef (preprod) > load_balancer.ec2.public_hostname
will return something similar to:
=> "ec2-111-22-333-44.compute-1.amazonaws.com"
The find
command can be used to search the Chef Infra Server from the
chef-shell. For example:
chef (preprod) > pp nodes.find(:ec2_public_hostname => 'ec2*')
You can also format the results with a code block. For example:
chef (preprod) > pp nodes.find(:ec2_public_hostname => 'ec2*') {|n| n.ec2.ami_id } and nil
will return something similar to:
=> ["ami-f8927a91",
"ami-f8927a91",
"ami-a89870c1",
"ami-a89870c1",
"ami-a89870c1",
"ami-a89870c1",
"ami-a89870c1"
# and more...
Or:
chef (preprod) > amis = nodes.find(:ec2_public_hostname => 'ec2*') {|n| n.ec2.ami_id }
chef (preprod) > puts amis.uniq.sort
will return something similar to:
=> ami-4b4ba522
ami-a89870c1
ami-eef61587
ami-f8927a91
Use Breakpoints
chef-shell allows the current position in a run-list to be manipulated during a Chef Infra Client run. Add breakpoints to a recipe to take advantage of this functionality.Step Through Run-list
To explore how using the breakpoint to manually step through a Chef Infra Client run, create a simple recipe in chef-shell:
chef > recipe_mode
chef:recipe > echo off
chef:recipe > file "/tmp/before-breakpoint"
chef:recipe > breakpoint "foo"
chef:recipe > file "/tmp/after-breakpoint"
and then run Chef Infra Client:
chef:recipe > run_chef
[Fri, 15 Jan 2020 14:17:49 -0800] DEBUG: Processing file[/tmp/before-breakpoint]
[Fri, 15 Jan 2020 14:17:49 -0800] DEBUG: file[/tmp/before-breakpoint] using Chef::Provider::File
[Fri, 15 Jan 2020 14:17:49 -0800] INFO: Creating file[/tmp/before-breakpoint] at /tmp/before-breakpoint
[Fri, 15 Jan 2020 14:17:49 -0800] DEBUG: Processing [./bin/../lib/chef/mixin/recipe_definition_dsl_core.rb:56:in 'new']
[Fri, 15 Jan 2020 14:17:49 -0800] DEBUG: [./bin/../lib/chef/mixin/recipe_definition_dsl_core.rb:56:in 'new'] using Chef::Provider::Breakpoint
Chef Infra Client ran the first resource before the breakpoint
(file[/tmp/before-breakpoint]
), but then stopped after execution. Chef
Infra Client attempted to name the breakpoint after its position in the
source file, but Chef Infra Client was confused because the resource was
entered interactively. From here, chef-shell can resume the interrupted
Chef Infra Client run:
chef:recipe > chef_run.resume
[Fri, 15 Jan 2020 14:27:08 -0800] INFO: Creating file[/tmp/after-breakpoint] at /tmp/after-breakpoint
A quick view of the /tmp
directory shows that the following files were
created:
after-breakpoint
before-breakpoint
You can rewind and step through a Chef Infra Client run:
chef:recipe > Chef::Log.level = :debug # debug logging won't turn on automatically in this case
=> :debug
chef:recipe > chef_run.rewind
=> 0
chef:recipe > chef_run.step
[Fri, 15 Jan 2020 14:40:52 -0800] DEBUG: Processing file[/tmp/before-breakpoint]
[Fri, 15 Jan 2020 14:40:52 -0800] DEBUG: file[/tmp/before-breakpoint] using Chef::Provider::File
=> 1
chef:recipe > chef_run.step
[Fri, 15 Jan 2020 14:40:54 -0800] DEBUG: Processing [./bin/../lib/chef/mixin/recipe_definition_dsl_core.rb:56:in 'new']
[Fri, 15 Jan 2020 14:40:54 -0800] DEBUG: [./bin/../lib/chef/mixin/recipe_definition_dsl_core.rb:56:in 'new'] using Chef::Provider::Breakpoint
=> 2
chef:recipe > chef_run.step
[Fri, 15 Jan 2020 14:40:56 -0800] DEBUG: Processing file[/tmp/after-breakpoint]
[Fri, 15 Jan 2020 14:40:56 -0800] DEBUG: file[/tmp/after-breakpoint] using Chef::Provider::File
=> 3
From the output, the rewound run-list is shown, but when the resources are executed again, they will repeat their checks for the existence of files. If they exist, Chef Infra Client will skip creating them. If the files are deleted, then:
chef:recipe > ls("/tmp").grep(/breakpoint/).each {|f| rm "/tmp/#{f}" }
=> ["after-breakpoint", "before-breakpoint"]
Rewind, and then resume your Chef Infra Client run to get the expected results:
chef:recipe > chef_run.rewind
chef:recipe > chef_run.resume
[Fri, 15 Jan 2020 14:48:56 -0800] DEBUG: Processing file[/tmp/before-breakpoint]
[Fri, 15 Jan 2020 14:48:56 -0800] DEBUG: file[/tmp/before-breakpoint] using Chef::Provider::File
[Fri, 15 Jan 2020 14:48:56 -0800] INFO: Creating file[/tmp/before-breakpoint] at /tmp/before-breakpoint
[Fri, 15 Jan 2020 14:48:56 -0800] DEBUG: Processing [./bin/../lib/chef/mixin/recipe_definition_dsl_core.rb:56:in 'new']
[Fri, 15 Jan 2020 14:48:56 -0800] DEBUG: [./bin/../lib/chef/mixin/recipe_definition_dsl_core.rb:56:in 'new'] using Chef::Provider::Breakpoint
chef:recipe > chef_run.resume
[Fri, 15 Jan 2020 14:49:20 -0800] DEBUG: Processing file[/tmp/after-breakpoint]
[Fri, 15 Jan 2020 14:49:20 -0800] DEBUG: file[/tmp/after-breakpoint] using Chef::Provider::File
[Fri, 15 Jan 2020 14:49:20 -0800] INFO: Creating file[/tmp/after-breakpoint] at /tmp/after-breakpoint
Debug Existing Recipe
chef-shell can be used to debug existing recipes. The recipe first needs to be added to a run-list for the node, so that it’s cached when starting chef-shell and then used for debugging. chef-shell will report which recipes are being cached when it’s started:
loading configuration: none (standalone session)
Session type: standalone
Loading.............done.
Welcome to the chef-shell 15.8.23
For usage see https://docs.chef.io/chef_shell.html
run `help' for help, `exit' or ^D to quit.
chef (15.8.23)>
To just load one recipe from the run-list, go into the recipe and use
the include_recipe
command. For example:
chef > recipe_mode
chef:recipe > include_recipe "getting-started"
=> [#< Chef::Recipe:0x10256f9e8 @cookbook_name="getting-started",
... output truncated ...
To load all of the recipes from a run-list, use code similar to the following:
node.run_list.expand(node.chef_environment).recipes.each do |r|
include_recipe r
end
After the recipes that are to be debugged have been loaded, use the
run_chef
command to run them.
Advanced Debugging
In chef-shell, it’s possible to get verbose debugging using the tracing feature in Interactive Ruby (IRb). chef-shell provides a shortcut for turning tracing on and off. For example:
chef > tracing on
tracing is on
=> nil
chef >
and:
chef > tracing off
#0:(irb):2:Object:-: tracing off
#0:/opt/chef-workstation/embedded/lib/ruby/gems/2.6.0/gems/chef-15.8.23/lib/chef/shell/ext.rb:109:Shell::Extensions::ObjectCoreExtensions:>: def off
#0:/opt/chef-workstation/embedded/lib/ruby/gems/2.6.0/gems/chef-15.8.23/lib/chef/shell/ext.rb:110:Shell::Extensions::ObjectCoreExtensions:-: :off
#0:/opt/chef-workstation/embedded/lib/ruby/gems/2.6.0/gems/chef-15.8.23/lib/chef/shell/ext.rb:111:Shell::Extensions::ObjectCoreExtensions:<: end
#0:/opt/chef-workstation/embedded/lib/ruby/gems/2.6.0/gems/chef-15.8.23/lib/chef/shell/ext.rb:272:main:>: def tracing(on_or_off)
#0:/opt/chef-workstation/embedded/lib/ruby/gems/2.6.0/gems/chef-15.8.23/lib/chef/shell/ext.rb:273:main:-: conf.use_tracer = on_or_off.on_off_to_bool
#0:/opt/chef-workstation/embedded/lib/ruby/gems/2.6.0/gems/chef-15.8.23/lib/chef/shell/ext.rb:162:Shell::Extensions::Symbol:>: def on_off_to_bool
#0:/opt/chef-workstation/embedded/lib/ruby/gems/2.6.0/gems/chef-15.8.23/lib/chef/shell/ext.rb:163:Shell::Extensions::Symbol:-: to_s.on_off_to_bool
#0:/opt/chef-workstation/embedded/lib/ruby/gems/2.6.0/gems/chef-15.8.23/lib/chef/shell/ext.rb:149:Shell::Extensions::String:>: def on_off_to_bool
#0:/opt/chef-workstation/embedded/lib/ruby/gems/2.6.0/gems/chef-15.8.23/lib/chef/shell/ext.rb:150:Shell::Extensions::String:-: case self
#0:/opt/chef-workstation/embedded/lib/ruby/gems/2.6.0/gems/chef-15.8.23/lib/chef/shell/ext.rb:154:Shell::Extensions::String:-: false
#0:/opt/chef-workstation/embedded/lib/ruby/gems/2.6.0/gems/chef-15.8.23/lib/chef/shell/ext.rb:158:Shell::Extensions::String:<: end
#0:/opt/chef-workstation/embedded/lib/ruby/gems/2.6.0/gems/chef-15.8.23/lib/chef/shell/ext.rb:164:Shell::Extensions::Symbol:<: end
tracing is off
=> nil
chef >
Debug Examples
The following examples show how to use chef-shell.
"Hello World"
This example shows how to run chef-shell in standalone mode. (For
chef-solo or Chef Infra Client modes, you would need to run chef-shell
using the -s
or -z
command line options, and then take into
consideration the necessary configuration settings.)
When Chef Infra Client is installed using RubyGems or a package manager,
chef-shell should already be installed. When Chef Infra Client is run
from a git clone, it will be located in chef/bin/chef shell
. To start
chef-shell, just run it without any options. You’ll see the loading
message, then the banner, and then the chef-shell prompt:
bin/chef-shell
loading configuration: none (standalone session)
Session type: standalone
Loading.............done.
Welcome to the chef-shell 15.8.23
For usage see https://docs.chef.io/chef_shell.html
run `help' for help, `exit' or ^D to quit.
chef (15.8.23)>
(Use the help command to print a list of supported commands.) Use the recipe_mode command to switch to recipe context:
chef > recipe_mode
chef:recipe_mode >
Typing is evaluated in the same context as recipes. Create a file resource:
chef:recipe_mode > file "/tmp/ohai2u_shef"
=> #< Chef::Resource::File:0x1b691ac
@enclosing_provider=nil,
@resource_name=:file,
@before=nil,
@supports={},
@backup=5,
@allowed_actions=[:nothing, :create, :delete, :touch, :create_if_missing],
@only_if=nil,
@noop=nil,
@collection=#< Chef::ResourceCollection:0x1b9926c
@insert_after_idx=nil,
@resources_by_name={"file[/tmp/ohai2u_shef]"=>0},
@resources=[#< Chef::Resource::File:0x1b691ac ...>]>,
@updated=false,
@provider=nil,
@node=< Chef::Node:0xdeeaae
@name="eigenstate.local">,
@recipe_name=nil,
@not_if=nil,
@name="/tmp/ohai2u_shef",
@action="create",
@path="/tmp/ohai2u_shef",
@source_line="/Users/username/ruby/chef/chef/(irb#1) line 1",
@params={},
@actions={},
@cookbook_name=nil,
@ignore_failure=false>
(The previous example was formatted for presentation.) At this point,
chef-shell has created the resource and put it in the run-list, but not
yet created the file. To initiate a Chef Infra Client run, use the
run_chef
command:
chef:recipe_mode > run_chef
[Fri, 15 Jan 2020 10:42:47 -0800] DEBUG: Processing file[/tmp/ohai2u_shef]
[Fri, 15 Jan 2020 10:42:47 -0800] DEBUG: file[/tmp/ohai2u_shef] using Chef::Provider::File
[Fri, 15 Jan 2020 10:42:47 -0800] INFO: Creating file[/tmp/ohai2u_shef] at /tmp/ohai2u_shef
=> true
chef-shell can also switch to the same context as attribute files. Set an attribute with the following syntax:
chef:recipe_mode > attributes_mode
chef:attributes > default[:hello] = "ohai2u-again"
=> "ohai2u-again"
chef:attributes >
Switch back to recipe_mode context and use the attributes:
chef:attributes > recipe_mode
=> :attributes
chef:recipe_mode > file "/tmp/#{node.hello}"
Now, run Chef Infra Client again:
chef:recipe_mode > run_chef
[Fri, 15 Jan 2020 10:53:22 -0800] DEBUG: Processing file[/tmp/ohai2u_shef]
[Fri, 15 Jan 2020 10:53:22 -0800] DEBUG: file[/tmp/ohai2u_shef] using Chef::Provider::File
[Fri, 15 Jan 2020 10:53:22 -0800] DEBUG: Processing file[/tmp/ohai2u-again]
[Fri, 15 Jan 2020 10:53:22 -0800] DEBUG: file[/tmp/ohai2u-again] using Chef::Provider::File
[Fri, 15 Jan 2020 10:53:22 -0800] INFO: Creating file[/tmp/ohai2u-again] at /tmp/ohai2u-again
=> true
chef:recipe_mode >
Because the first resource (file[/tmp/ohai2u_shef]
) is still in the
run-list, it gets executed again. And because that file already exists,
Chef Infra Client doesn’t attempt to re-create it. Finally, the files
were created using the ls
method:
chef:recipe_mode > ls("/tmp").grep(/ohai/)
=> ["ohai2u-again", "ohai2u_shef"]
Shell Tutorial
Get Specific Nodes
To get a list of nodes using a recipe named postfix
use
search(:node,"recipe:postfix")
. To get a list of nodes using a
sub-recipe named delivery
, use chef-shell. For example:
search(:node, 'recipes:postfix\:\:delivery')
Note
Single (’ ‘) vs. double (" “) is important. This is because a backslash () needs to be included in the string, instead of having Ruby interpret it as an escape.
Examples
The following examples demonstrate various approaches for using the breakpoint resource in recipes:
A recipe without a breakpoint
yum_key node['yum']['elrepo']['key'] do
url node['yum']['elrepo']['key_url']
action :add
end
yum_repository 'elrepo' do
description 'ELRepo.org Community Enterprise Linux Extras Repository'
key node['yum']['elrepo']['key']
mirrorlist node['yum']['elrepo']['url']
includepkgs node['yum']['elrepo']['includepkgs']
exclude node['yum']['elrepo']['exclude']
action :create
end
The same recipe with breakpoints
In the following example, the name of each breakpoint is an arbitrary string.
breakpoint "before yum_key node['yum']['repo_name']['key']" do
action :break
end
yum_key node['yum']['repo_name']['key'] do
url node['yum']['repo_name']['key_url']
action :add
end
breakpoint "after yum_key node['yum']['repo_name']['key']" do
action :break
end
breakpoint "before yum_repository 'repo_name'" do
action :break
end
yum_repository 'repo_name' do
description 'description'
key node['yum']['repo_name']['key']
mirrorlist node['yum']['repo_name']['url']
includepkgs node['yum']['repo_name']['includepkgs']
exclude node['yum']['repo_name']['exclude']
action :create
end
breakpoint "after yum_repository 'repo_name'" do
action :break
end
In the previous examples, the names are used to indicate if the breakpoint is before or after a resource and also to specify which resource it is before or after.