Implement `--config-option` CLI opt for knifedan/config-option-in-knife

The `--config-option` CLI option allows setting any `Chef::Config`
setting on the command line, which allows applications to be used
without a configuration file even if a desired config option does not
have a corresponding CLI option. This CLI option was present in the help
output for knife but was not actually implemented. Moving the behavior
into chef-config allows us to use it for both `chef-client` and `knife`.

Signed-off-by: Daniel DeLeo <dan@chef.io>

1 files changed, 20 insertions, 0 deletions

diff --git a/chef-config/lib/chef-config/config.rb b/chef-config/lib/chef-config/config.rb
index f2db54aa17..d0fa87a5ad 100644
--- a/chef-config/lib/chef-config/config.rb
+++ b/chef-config/lib/chef-config/config.rb
@@ -32,6 +32,7 @@ require "mixlib/shellout"
 require "uri"
 require "addressable/uri"
 require "openssl"
+require "yaml"
 
 module ChefConfig
 
@@ -70,6 +71,25 @@ module ChefConfig
       event_handlers << logger
     end
 
+    def self.apply_extra_config_options(extra_config_options)
+      if extra_config_options
+        extra_parsed_options = extra_config_options.inject({}) do |memo, option|
+          # Sanity check value.
+          if option.empty? || !option.include?("=")
+            raise UnparsableConfigOption, "Unparsable config option #{option.inspect}"
+          end
+          # Split including whitespace if someone does truly odd like
+          # --config-option "foo = bar"
+          key, value = option.split(/\s*=\s*/, 2)
+          # Call to_sym because Chef::Config expects only symbol keys. Also
+          # runs a simple parse on the string for some common types.
+          memo[key.to_sym] = YAML.safe_load(value)
+          memo
+        end
+        merge!(extra_parsed_options)
+      end
+    end
+
     # Config file to load (client.rb, knife.rb, etc. defaults set differently in knife, chef-client, etc.)
     configurable(:config_file)