Class: Shamu::Features::EnvStore

Inherits:
Services::Service show all
Defined in:
lib/shamu/features/env_store.rb

Overview

Expose a read-only runtime environment for consumption by the FeaturesService. By default blends a Rack env request headers (if using Rack) with the host env. The request env overrides the host.

When fetching, EnvStore will look for an X-Shamu-Features header sent in the HTTP request. It should be constructed using pack to build a verifiable hash of feature settings.

If a rack value is not set, EnvStore will fall back to looking for the toggle in the host's environment with the name TOGGLE_{ toggle name upcased and underscored }. For example buy_now/one_click will look for TOGGLE_BUY_NOW_ONE_CLICK in the environment.

Constant Summary collapse

RACK_ENV_KEY = 
"HTTP_X_SHAMU_FEATURES".freeze
RACK_PARAMS_KEY = 
"shamu.features".freeze
RACK_PARAMS_FEATURES_KEY = 
"shamu.features.from_params".freeze
RACK_HEADER_FEATURES_KEY = 
"shamu.features.from_header".freeze

Dependencies collapse

Class Method Summary collapse

Instance Method Summary collapse

Methods inherited from Services::Service

#cache_for, #cached_lookup, #entity_list, #entity_lookup_list, #error, #find_by_lookup, #lazy_association, #lookup_association

Instance Attribute Details

#codec ⇒ ToggleCode

Returns code used to pack and unpack the features.

Returns:

  • (ToggleCode) —

    code used to pack and unpack the features.



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# File 'lib/shamu/features/env_store.rb', line 29

attr_dependency :codec, ToggleCodec

Class Method Details

.env_key_name(key) ⇒ String

Returns the expected ENV key name for the given toggle name.

Returns:

  • (String) —

    the expected ENV key name for the given toggle name.



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# File 'lib/shamu/features/env_store.rb', line 41

def self.env_key_name( key )
  key = key.upcase
  key.tr! "/", "_"
  key
end

Instance Method Details

#fetch(key, &block) ⇒ Object

Fetch a value from the environment.



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# File 'lib/shamu/features/env_store.rb', line 35

def fetch( key, &block )
  return env_fetch( key, &block ) unless defined? Rack
  rack_params_fetch( key, &block )
end