powershell_script Resource
This page is generated from the Chef Infra Client source code.To suggest a change, edit the powershell_script.rb file and submit a pull request to the Chef Infra Client repository.
Use the powershell_script resource to execute a script using the Windows PowerShell interpreter, much like how the script and script-based resources bash, csh, perl, python, and ruby are used. The powershell_script resource is specific to the Microsoft Windows platform, but may use both the Windows PowerShell interpreter or the PowerShell Core (pwsh) interpreter as of Chef Infra Client 16.6 and later.
The powershell_script resource creates and executes a temporary file rather than running the command inline. Commands that are executed with this resource are (by their nature) not idempotent, as they are typically unique to the environment in which they are run. Use not_if
and only_if
conditionals to guard this resource for idempotence.
Syntax
A powershell_script resource block executes a batch script using the Windows PowerShell interpreter. For example, writing to an interpolated path:
powershell_script 'write-to-interpolated-path' do
code <<-EOH
$stream = [System.IO.StreamWriter] "#{Chef::Config[:file_cache_path]}/powershell-test.txt"
$stream.WriteLine("In #{Chef::Config[:file_cache_path]}...word.")
$stream.close()
EOH
end
The full syntax for all of the properties that are available to the powershell_script resource is:
powershell_script 'name' do
code String
command String, Array # default value: 'name' unless specified
convert_boolean_return true, false # default value: false
creates String
cwd String
domain String
elevated true, false # default value: false
environment Hash
flags String
group String, Integer
input String
interpreter String # default value: "powershell"
live_stream true, false # default value: false
password String
returns Integer, Array # default value: 0
timeout Integer, String, Float # default value: 3600
use_inline_powershell true, false # default value: false
user String, Integer
action Symbol # defaults to :run if not specified
end
where:
powershell_script
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.code
,command
,convert_boolean_return
,creates
,cwd
,domain
,elevated
,environment
,flags
,group
,input
,interpreter
,live_stream
,password
,returns
,timeout
,use_inline_powershell
, anduser
are the properties available to this resource.
Actions
The powershell_script resource has the following actions:
:nothing
- This resource block does not 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.
:run
- Run a command. (default)
Properties
The powershell_script resource has the following properties:
code
- Ruby Type: String |
REQUIRED
A quoted string of code to be executed.
command
- Ruby Type: String, Array | Default Value:
The resource block's name
An optional property to set the command to be executed if it differs from the resource block’s name.
convert_boolean_return
- Ruby Type: true, false | Default Value:
false
Return
0
if the last line of a command is evaluated to be true or to return1
if the last line is evaluated to be false.When the
guard_interpreter
common attribute is set to:powershell_script
, a string command will be evaluated as if this value were set totrue
. This is because the behavior of this attribute is similar to the value of the"$?"
expression common in UNIX interpreters. For example, this:powershell_script 'make_safe_backup' do guard_interpreter :powershell_script code 'cp ~/data/nodes.json ~/data/nodes.bak' not_if 'test-path ~/data/nodes.bak' end
is similar to:
bash 'make_safe_backup' do code 'cp ~/data/nodes.json ~/data/nodes.bak' not_if 'test -e ~/data/nodes.bak' end
creates
- Ruby Type: String
Prevent a command from creating a file when that file already exists.
cwd
- Ruby Type: String
The current working directory from which the command will be run.
domain
- Ruby Type: String
Windows only: The domain of the user specified by the user property. If not specified, the username and password specified by the
user
andpassword
properties will be used to resolve that user against the domain in which the system running Chef Infra Client is joined, or if that system is not joined to a domain it will resolve the user as a local account on that system. An alternative way to specify the domain is to leave this property unspecified and specify the domain as part of the user property.New in Chef Client 12.21
elevated
- Ruby Type: true, false | Default Value:
false
Determines whether the script will run with elevated permissions to circumvent User Access Control (UAC) from interactively blocking the process. This will cause the process to be run under a batch login instead of an interactive login. The user running chef-client needs the ‘Replace a process level token’ and ‘Adjust Memory Quotas for a process’ permissions. The user that is running the command needs the ‘Log on as a batch job’ permission. Because this requires a login, the user and password properties are required.
New in Chef Client 13.3
environment
- Ruby Type: Hash
A Hash of environment variables in the form of
({'ENV_VARIABLE' => 'VALUE'})
. Note: These variables must exist for a command to be run successfully.
flags
- Ruby Type: String
A string that is passed to the Windows PowerShell command value (Windows PowerShell 3.0+):
-NoLogo
-NonInteractive
-NoProfile
-ExecutionPolicy Bypass
-InputFormat None
group
- Ruby Type: String, Integer
The group name or group ID that must be changed before running a command.
guard_interpreter
- Ruby Type: Symbol | Default Value:
:powershell_script
When this property is set to
:powershell_script
, the 64-bit version of the Windows PowerShell shell will be used to evaluate strings values for thenot_if
andonly_if
properties. Set this value to:default
to use the 32-bit version of the cmd.exe shell.
input
- Ruby Type: String
An optional property to set the input sent to the command as STDIN.
New in Chef Infra Client 16.2
interpreter
- Ruby Type: String | Default Value:
powershell
Allowed Values:"powershell", "pwsh"
The interpreter type,
powershell
orpwsh
(PowerShell Core)
live_stream
- Ruby Type: true, false | Default Value:
false
Send the output of the command run by this execute resource block to the Chef Infra Client event stream.
password
- Ruby Type: String
Windows only The password of the user specified by the user property. This property is mandatory if user is specified on Windows and may only be specified if user is specified. The sensitive property for this resource will automatically be set to true if password is specified.
New in Chef Client 12.21
returns
- Ruby Type: Integer, Array | Default Value:
0
The return value for a command. This may be an array of accepted values. An exception is raised when the return value(s) do not match.
timeout
- Ruby Type: Integer, String, Float | Default Value:
3600
The amount of time (in seconds) a command is to wait before timing out.
use_inline_powershell
- Ruby Type: true, false | Default Value:
false
Use the inline PowerShell DLL rather than shelling out. The PowerShell DLL is faster, but its semantics could be different from shelling out. In particular, it doesn’t allow for streaming output, nor does it allow for passing custom parameters to the interpreter.
New in Chef Infra Client 18.4
user
- Ruby Type: String, Integer
The user name of the user identity with which to launch the new process. The user name may optionally be specified with a domain, i.e.
domain\user
oruser@my.dns.domain.com
via Universal Principal Name (UPN)format. It can also be specified without a domain simply as user if the domain is instead specified using the domain property. On Windows only, if this property is specified, the password property must be specified.
Common Resource Functionality
Chef resources include common properties, notifications, and resource guards.
Common Properties
The following properties are common to every resource:
compile_time
Ruby Type: true, false | Default Value:
false
Control the phase during which the resource is run on the node. Set to true to run while the resource collection is being built (the
compile phase
). Set to false to run while Chef Infra Client is configuring the node (theconverge phase
).ignore_failure
Ruby Type: true, false, :quiet | Default Value:
false
Continue running a recipe if a resource fails for any reason.
:quiet
will not display the full stack trace and the recipe will continue to run if a resource fails.retries
Ruby Type: Integer | Default Value:
0
The number of attempts to catch exceptions and retry the resource.
retry_delay
Ruby Type: Integer | Default Value:
2
The delay in seconds between retry attempts.
sensitive
Ruby Type: true, false | Default Value:
false
Ensure that sensitive resource data is not logged by Chef Infra Client.
Notifications
notifies
Ruby Type: Symbol, 'Chef::Resource[String]'
A resource may notify another resource to take action when its state changes. Specify a
'resource[name]'
, the:action
that resource should take, and then the:timer
for that action. A resource may notify more than one resource; use anotifies
statement for each resource to be notified.If the referenced resource does not exist, an error is raised. In contrast,
subscribes
will not fail if the source resource is not found.
A timer specifies the point during a Chef Infra Client run at which a notification is run. The following timers are available:
:before
Specifies that the action on a notified resource should be run before processing the resource block in which the notification is located.
:delayed
Default. Specifies that a notification should be queued up, and then executed at the end of a Chef Infra Client run.
:immediate
,:immediately
Specifies that a notification should be run immediately, for each resource notified.
The syntax for notifies
is:
notifies :action, 'resource[name]', :timer
subscribes
Ruby Type: Symbol, 'Chef::Resource[String]'
A resource may listen to another resource, and then take action if the
state of the resource being listened to changes. Specify a
'resource[name]'
, the :action
to be taken, and then the :timer
for
that action.
Note that subscribes
does not apply the specified action to the
resource that it listens to - for example:
file '/etc/nginx/ssl/example.crt' do
mode '0600'
owner 'root'
end
service 'nginx' do
subscribes :reload, 'file[/etc/nginx/ssl/example.crt]', :immediately
end
In this case the subscribes
property reloads the nginx
service
whenever its certificate file, located under
/etc/nginx/ssl/example.crt
, is updated. subscribes
does not make any
changes to the certificate file itself, it merely listens for a change
to the file, and executes the :reload
action for its resource (in this
example nginx
) when a change is detected.
If the other resource does not exist, the subscription will not raise an
error. Contrast this with the stricter semantics of notifies
, which
will raise an error if the other resource does not exist.
A timer specifies the point during a Chef Infra Client run at which a notification is run. The following timers are available:
:before
Specifies that the action on a notified resource should be run before processing the resource block in which the notification is located.
:delayed
Default. Specifies that a notification should be queued up, and then executed at the end of a Chef Infra Client run.
:immediate
,:immediately
Specifies that a notification should be run immediately, for each resource notified.
The syntax for subscribes
is:
subscribes :action, 'resource[name]', :timer
Guards
A guard property can be used to evaluate the state of a node during the execution phase of a Chef Infra Client run. Based on the results of this evaluation, a guard property is then used to tell Chef Infra Client if it should continue executing a resource. A guard property accepts either a string value or a Ruby block value:
- A string is executed as a shell command. If the command returns
0
, the guard is applied. If the command returns any other value, then the guard property is not applied. String guards in a powershell_script run Windows PowerShell commands and may returntrue
in addition to0
. - A block is executed as Ruby code that must return either
true
orfalse
. If the block returnstrue
, the guard property is applied. If the block returnsfalse
, the guard property is not applied.
A guard property is useful for ensuring that a resource is idempotent by allowing that resource to test for the desired state as it is being executed, and then if the desired state is present, for Chef Infra Client to do nothing.
PropertiesThe following properties can be used to define a guard that is evaluated during the execution phase of a Chef Infra Client run:
not_if
Prevent a resource from executing when the condition returns
true
.only_if
Allow a resource to execute only if the condition returns
true
.
Examples
The following examples demonstrate various approaches for using the powershell_script resource in recipes:
Write to an interpolated path:
powershell_script 'write-to-interpolated-path' do
code <<-EOH
$stream = [System.IO.StreamWriter] "#{Chef::Config[:file_cache_path]}/powershell-test.txt"
$stream.WriteLine("In #{Chef::Config[:file_cache_path]}...word.")
$stream.close()
EOH
end
Change the working directory:
powershell_script 'cwd-then-write' do
cwd Chef::Config[:file_cache_path]
code <<-EOH
$stream = [System.IO.StreamWriter] "C:/powershell-test2.txt"
$pwd = pwd
$stream.WriteLine("This is the contents of: $pwd")
$dirs = dir
foreach ($dir in $dirs) {
$stream.WriteLine($dir.fullname)
}
$stream.close()
EOH
end
Change the working directory in Microsoft Windows:
powershell_script 'cwd-to-win-env-var' do
cwd '%TEMP%'
code <<-EOH
$stream = [System.IO.StreamWriter] "./temp-write-from-chef.txt"
$stream.WriteLine("chef on windows rox yo!")
$stream.close()
EOH
end
Pass an environment variable to a script:
powershell_script 'read-env-var' do
cwd Chef::Config[:file_cache_path]
environment ({'foo' => 'BAZ'})
code <<-EOH
$stream = [System.IO.StreamWriter] "./test-read-env-var.txt"
$stream.WriteLine("FOO is $env:foo")
$stream.close()
EOH
end
Evaluate for true and/or false:
Use the convert_boolean_return
attribute to raise an exception when
certain conditions are met. For example, the following fragments will
run successfully without error:
powershell_script 'false' do
code '$false'
end
and:
powershell_script 'true' do
code '$true'
end
whereas the following will raise an exception:
powershell_script 'false' do
convert_boolean_return true
code '$false'
end
Use the flags attribute:
powershell_script 'Install IIS' do
code <<-EOH
Import-Module ServerManager
Add-WindowsFeature Web-Server
EOH
flags '-NoLogo, -NonInteractive, -NoProfile, -ExecutionPolicy Unrestricted, -InputFormat None, -File'
guard_interpreter :powershell_script
not_if '(Get-WindowsFeature -Name Web-Server).Installed'
end
Rename computer, join domain, reboot:
The following example shows how to rename a computer, join a domain, and then reboot the computer:
reboot 'Restart Computer' do
action :nothing
end
powershell_script 'Rename and Join Domain' do
code <<-EOH
...your rename and domain join logic here...
EOH
not_if <<-EOH
$ComputerSystem = gwmi win32_computersystem
($ComputerSystem.Name -like '#{node['some_attribute_that_has_the_new_name']}') -and
$ComputerSystem.partofdomain)
EOH
notifies :reboot_now, 'reboot[Restart Computer]', :immediately
end
where:
- The powershell_script resource block renames a computer, and then joins a domain.
- The reboot resource restarts the computer.
- The
not_if
guard prevents the Windows PowerShell script from running when the settings in thenot_if
guard match the desired state. - The
notifies
statement tells the reboot resource block to run if the powershell_script block was executed during a Chef Infra Client run.
Run a command as an alternate user:
Note: When Chef is running as a service, this feature
requires that the user that Chef runs as has SeAssignPrimaryTokenPrivilege
(aka SE_ASSIGNPRIMARYTOKEN_NAME
) user right. By default only LocalSystem
and NetworkService have this right when running as a service. This is necessary
even if the user is an Administrator.
This right can be added and checked in a recipe using this example:
# Add 'SeAssignPrimaryTokenPrivilege' for the user
Chef::ReservedNames::Win32::Security.add_account_right('<user>', 'SeAssignPrimaryTokenPrivilege')
# Check if the user has 'SeAssignPrimaryTokenPrivilege' rights
Chef::ReservedNames::Win32::Security.get_account_right('<user>').include?('SeAssignPrimaryTokenPrivilege')
The following example shows how to run mkdir test_dir
from a Chef Infra Client run as an alternate user.
# Passing only username and password
powershell_script 'mkdir test_dir' do
code "mkdir test_dir"
cwd Chef::Config[:file_cache_path]
user "username"
password "password"
end
# Passing username and domain
powershell_script 'mkdir test_dir' do
code "mkdir test_dir"
cwd Chef::Config[:file_cache_path]
domain "domain"
user "username"
password "password"
end
# Passing username = 'domain-name\\username'. No domain is passed
powershell_script 'mkdir test_dir' do
code "mkdir test_dir"
cwd Chef::Config[:file_cache_path]
user "domain-name\\username"
password "password"
end
# Passing username = 'username@domain-name'. No domain is passed
powershell_script 'mkdir test_dir' do
code "mkdir test_dir"
cwd Chef::Config[:file_cache_path]
user "username@domain-name"
password "password"
end
# Work around User Access Control (UAC)
powershell_script 'mkdir test_dir' do
code "mkdir test_dir"
cwd Chef::Config[:file_cache_path]
user "username"
password "password"
elevated true
end