knife-environment - Define cookbook policies for the environments in your infrastructure
knife environment sub-command (options)
Environment subcommands follow a basic create, read, update, delete (CRUD) pattern. The following subcommands are available:
knife environment create environment (options)
-d, --description DESCRIPTIONCreate a new environment object on the Chef Server. The envrionment will be opened in the text editor for editing prior to creation if the -n option is not present.
knife environment delete environment (options)
Destroy an environment on the Chef Server. A prompt for confirmation will be displayed if the -y options is not given.
knife environment edit environment (options)
Fetch environment and display it in the text editor for editing. The environment will be saved to the Chef Server when the editing session exits.
knife environment from file file (options)
Create or update an environment from the JSON or Ruby format file. See format for the proper format of this file.
knife environment list (options)
* -w, --with-uri:
Show the resource URI for each environment
knife environment show environment (options)
Environments provide a means to apply policies to hosts in your infrastructure based on business function. For example, you may have a separate copy of your infrastructure called "dev" that runs the latest version of your application and should use the newest versions of your cookbooks when configuring systems, and a production instance of your infrastructure where you wish to update code and cookbooks in a more controlled fashion. In Chef, this function is implemented with environments.
Environments contain two major components: a set of cookbook version constraints and environment attributes.
A cookbook version constraint is comprised of a cookbook name and a version constraint. The cookbook name is the name of a cookbook in your system, and the version constraint is a String describing the version(s) of that cookbook allowed in the environment. Only one version constraint is supported for a given cookbook name.
The exact syntax used to define a cookbook version constraint varies depending on whether you use the JSON format or the Ruby format. In the JSON format, the cookbook version constraints for an environment are represented as a single JSON object, like this:
{"apache2": ">= 1.5.0"}
In the Ruby format, the cookbook version contraints for an environment are represented as a Ruby Hash, like this:
{"apache2" => ">= 1.5.0"}
A version number is a String comprised of two or three digits separated by a dot (.) character, or in other words, strings of the form "major.minor" or "major.minor.patch". "1.2" and "1.2.3" are examples of valid version numbers. Version numbers containing more than three digits or alphabetic characters are not supported.
A version constraint String is composed of an operator and a version number. The following operators are available:
= VERSION> VERSIONVERSION may be used.>= VERSION< VERSION<= VERSION~> VERSION~> 1.1 will match any
version less than 2.0 and greater than or equal to 1.1.0,
whereas ~> 2.0.5 will match any version less than 2.1.0 and
greater than or equal to 2.0.5.The JSON format of an envioronment is as follows:
{
"name": "dev",
"description": "The development environment",
"cookbook_versions": {
"couchdb": "= 11.0.0"
},
"json_class": "Chef::Environment",
"chef_type": "environment",
"default_attributes": {
"apache2": { "listen_ports": [ "80", "443" ] }
},
"override_attributes": {
"aws_s3_bucket": "production"
}
}
The Ruby format of an environment is as follows:
name "dev"
description "The development environment"
cookbook_versions "couchdb" => "= 11.0.0"
default_attributes "apache2" => { "listen_ports" => [ "80", "443" ] }
override_attributes "aws_s3_bucket" => "production"
knife-node(1) knife-cookbook(1) knife-role(1) http://wiki.opscode.com/display/chef/Environments http://wiki.opscode.com/display/chef/Version+Constraints
Chef was written by Adam Jacob adam@opscode.com with many contributions from the community.
This manual page was written by Daniel DeLeo dan@opscode.com. Permission is granted to copy, distribute and / or modify this document under the terms of the Apache 2.0 License.
Knife is distributed with Chef. http://wiki.opscode.com/display/chef/Home