knife_xargs.md

+++ title = "knife xargs" draft = false

gh_repo = "chef-workstation"

aliases = ["/knife_xargs.html", "/knife_xargs/"]

[menu] [menu.workstation] title = "knife xargs" identifier = "chef_workstation/chef_workstation_tools/knife/knife_xargs.md knife xargs" parent = "chef_workstation/chef_workstation_tools/knife" +++

{{< readfile file="content/workstation/reusable/md/knife_xargs_summary.md" >}}

Syntax

This subcommand has the following syntax:

knife xargs [PATTERN...] (options)

Options

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{{< readfile file="content/workstation/reusable/md/knife_common_see_common_options_link.md" >}}

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This subcommand has the following options:

-0

: Default: false.

--chef-repo-path PATH

: The path to the chef-repo. This setting will override the default path to the chef-repo. Default: same value as specified by chef_repo_path in client.rb.

--concurrency

: The number of allowed concurrent connections. Default: 10.

--[no-]diff

: Show a diff when a file changes. Default: --diff.

--dry-run

: Prevent changes from being uploaded to the Chef Infra Server. Default: false.

--[no-]force

: Force the upload of files even if they haven't been changed. Default: --no-force.

-I REPLACE_STRING, --replace REPLACE_STRING

: Define a string that is to be used to replace all occurrences o file name. Default: nil.

-J REPLACE_STRING, --replace-first REPLACE_STRING

: Define a string that is to be used to replace the first occurrence of a file name. Default: nil.

--local

: Build or execute a command line against a local file. Set to false to build or execute against a remote file. Default: false.

-n MAX_ARGS, --max-args MAX_ARGS

: The maximum number of arguments per command line. Default: nil.

-p [PATTERN...], --pattern [PATTERN...]

: One (or more) patterns for a command line. If this option is not specified, a list of patterns may be expected on standard input. Default: nil.

--repo-mode MODE

: The layout of the local chef-repo. Possible values: static, everything, or hosted_everything. Use static for just roles, environments, cookbooks, and data bags. By default, everything and hosted_everything are dynamically selected depending on the server type. Default value: default.

-s LENGTH, --max-chars LENGTH

: The maximum size (in characters) for a command line. Default: nil.

-t

: Run the print command on the command line. Default: nil.

{{< note >}}

{{< readfile file="content/workstation/reusable/md/knife_common_see_all_config_options.md" >}}

{{< /note >}}

Examples

The following examples show how to use this knife subcommand:

Find, and then replace data

The following example will go through all nodes on the server, and then replace the word foobar with baz:

knife xargs --pattern /nodes/* "perl -i -pe 's/foobar/baz'"

Use output of knife list and Perl

The following examples show various ways of listing all nodes on the server, and then using Perl to replace grantmc with gmc:

knife list 'nodes/*' | knife xargs "perl -i -pe 's/grantmc/gmc'"

or without quotes and the backslash escaped:

knife list /nodes/\* | knife xargs "perl -i -pe 's/grantmc/gmc'"

or by using the --pattern option:

knife xargs --pattern '/nodes.*' "perl -i -pe 's/grantmc/gmc'"

View security groups data

The following example shows how to display the content of all groups on the server:

knife xargs --pattern '/groups/*' cat

and will return something like:

{
  "name": "4bd14db60aasdfb10f525400cdde21",
  "users": [
    "grantmc"
  ]
}{
  "name": "62c4e268e15fasdasc525400cd944b",
  "users": [
    "robertf"
  ]
}{
  "name": "admins",
  "users": [
    "grantmc",
    "robertf"
  ]
}{
  "name": "billing-admins",
  "users": [
    "dtek"
  ]
}{
  "name": "clients",
  "clients": [
    "12345",
    "67890",
  ]
}{
  "name": "users",
  "users": [
    "grantmc"
    "robertf"
    "dtek"
  ],
  "groups": [
    "4bd14db60aasdfb10f525400cdde21",
    "62c4e268e15fasdasc525400cd944b"
  ]
}