Class: ActiveRecord::DatabaseConfigurations
Relationships & Source Files | |
Namespace Children | |
Classes:
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Exceptions:
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Inherits: | Object |
Defined in: | activerecord/lib/active_record/database_configurations.rb, activerecord/lib/active_record/database_configurations/connection_url_resolver.rb, activerecord/lib/active_record/database_configurations/database_config.rb, activerecord/lib/active_record/database_configurations/hash_config.rb, activerecord/lib/active_record/database_configurations/url_config.rb |
Overview
DatabaseConfigurations
returns an array of DatabaseConfig
objects that are constructed from the application’s database configuration hash or URL string.
The array of DatabaseConfig
objects in an application default to either a HashConfig
or UrlConfig
. You can retrieve your application’s config by using Base.configurations.
If you register a custom handler, objects will be created according to the conditions of the handler. See .register_db_config_handler for more on registering custom handlers.
Class Method Summary
- .new(configurations = {}) ⇒ DatabaseConfigurations constructor
-
.register_db_config_handler(&block)
Allows an application to register a custom handler for database configuration objects.
Instance Attribute Summary
-
#blank?
readonly
Alias for #empty?.
- #configurations readonly
-
#empty? ⇒ Boolean
(also: #blank?)
readonly
Checks if the application’s configurations are empty.
Instance Method Summary
- #any? ⇒ Boolean
-
#configs_for(env_name: nil, name: nil, config_key: nil, include_hidden: false)
Collects the configs for the environment and optionally the specification name passed in.
-
#find_db_config(env)
Returns a single
DatabaseConfig
object based on the requested environment.
Constructor Details
.new(configurations = {}) ⇒ DatabaseConfigurations
# File 'activerecord/lib/active_record/database_configurations.rb', line 73
def initialize(configurations = {}) @configurations = build_configs(configurations) end
Class Method Details
.register_db_config_handler(&block)
Allows an application to register a custom handler for database configuration objects. This is useful for creating a custom handler that responds to methods your application needs but Active Record doesn’t implement. For example if you are using Vitess, you may want your Vitess configurations to respond to sharded?
. To implement this define the following in an initializer:
ActiveRecord::DatabaseConfigurations.register_db_config_handler do |env_name, name, url, config|
next unless config.key?(:vitess)
VitessConfig.new(env_name, name, config)
end
Note: applications must handle the condition in which custom config should be created in your handler registration otherwise all objects will use the custom handler.
Then define your VitessConfig
to respond to the methods your application needs. It is recommended that you inherit from one of the existing database config classes to avoid having to reimplement all methods. Custom config handlers should only implement methods Active Record does not.
class VitessConfig < ActiveRecord::DatabaseConfigurations::UrlConfig
def sharded?
configuration_hash.fetch("sharded", false)
end
end
For configs that have a :vitess
key, a VitessConfig
object will be created instead of a DatabaseConfigurations::UrlConfig
.
# File 'activerecord/lib/active_record/database_configurations.rb', line 61
def self.register_db_config_handler(&block) db_config_handlers << block end
Instance Attribute Details
#blank? (readonly)
Alias for #empty?.
# File 'activerecord/lib/active_record/database_configurations.rb', line 153
alias :blank? :empty?
#configurations (readonly)
[ GitHub ]# File 'activerecord/lib/active_record/database_configurations.rb', line 26
attr_reader :configurations
#empty? ⇒ Boolean
(readonly)
Also known as: #blank?
Checks if the application’s configurations are empty.
# File 'activerecord/lib/active_record/database_configurations.rb', line 150
def empty? configurations.empty? end
Instance Method Details
#any? ⇒ Boolean
# File 'activerecord/lib/active_record/database_configurations.rb', line 27
delegate :any?, to: :configurations
#configs_for(env_name: nil, name: nil, config_key: nil, include_hidden: false)
Collects the configs for the environment and optionally the specification name passed in. To include replica configurations pass include_hidden: true
.
If a name is provided a single DatabaseConfigurations::DatabaseConfig
object will be returned, otherwise an array of DatabaseConfigurations::DatabaseConfig
objects will be returned that corresponds with the environment and type requested.
Options
-
env_name:
The environment name. Defaults tonil
which will collect configs for all environments. -
name:
The db config name (i.e. primary, animals, etc.). Defaults tonil
. If noenv_name
is specified the config for the default env and the passedname
will be returned. -
config_key:
Selects configs that contain a particular key in the configuration hash. Useful for selecting configs that use a custom db config handler or finding configs with hashes that contain a particular key. -
include_hidden:
Determines whether to include replicas and configurations hidden bydatabase_tasks: false
in the returned list. Most of the time we’re only iterating over the primary connections (i.e. migrations don’t need to run for the write and read connection). Defaults tofalse
.
# File 'activerecord/lib/active_record/database_configurations.rb', line 98
def configs_for(env_name: nil, name: nil, config_key: nil, include_hidden: false) env_name ||= default_env if name configs = env_with_configs(env_name) unless include_hidden configs = configs.select do |db_config| db_config.database_tasks? end end if config_key configs = configs.select do |db_config| db_config.configuration_hash.key?(config_key) end end if name configs.find do |db_config| db_config.name == name end else configs end end
#find_db_config(env)
Returns a single DatabaseConfigurations::DatabaseConfig
object based on the requested environment.
If the application has multiple databases find_db_config
will return the first DatabaseConfigurations::DatabaseConfig
for the environment.
# File 'activerecord/lib/active_record/database_configurations.rb', line 127
def find_db_config(env) env = env.to_s configurations.find do |db_config| db_config.for_current_env? && (db_config.env_name == env || db_config.name == env) end || configurations.find do |db_config| db_config.env_name == env end end