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module ActiveRecord::ConnectionHandling
Constants
- DEFAULT_ENV
- RAILS_ENV
Public Instance Methods
# File activerecord/lib/active_record/connection_handling.rb, line 117
def connected?
connection_handler.connected?(self)
end
Returns true
if Active Record is connected.
# File activerecord/lib/active_record/connection_handling.rb, line 86
def connection
retrieve_connection
end
Returns the connection currently associated with the class. This can also be used to “borrow” the connection to do database work unrelated to any of the specific Active Records.
# File activerecord/lib/active_record/connection_handling.rb, line 104
def connection_config
connection_pool.spec.config
end
Returns the configuration of the associated connection as a hash:
ActiveRecord::Base.connection_config
# => {pool: 5, timeout: 5000, database: "db/development.sqlite3", adapter: "sqlite3"}
Please use only for reading.
# File activerecord/lib/active_record/connection_handling.rb, line 90
def connection_id
ActiveRecord::RuntimeRegistry.connection_id
end
# File activerecord/lib/active_record/connection_handling.rb, line 94
def connection_id=(connection_id)
ActiveRecord::RuntimeRegistry.connection_id = connection_id
end
# File activerecord/lib/active_record/connection_handling.rb, line 108
def connection_pool
connection_handler.retrieve_connection_pool(self) or raise ConnectionNotEstablished
end
# File activerecord/lib/active_record/connection_handling.rb, line 47
def establish_connection(spec = nil)
spec ||= DEFAULT_ENV.call.to_sym
resolver = ConnectionAdapters::ConnectionSpecification::Resolver.new configurations
spec = resolver.spec(spec)
unless respond_to?(spec.adapter_method)
raise AdapterNotFound, "database configuration specifies nonexistent #{spec.config[:adapter]} adapter"
end
remove_connection
connection_handler.establish_connection self, spec
end
Establishes the connection to the database. Accepts a hash as input where the :adapter
key must be specified with the name of a database adapter (in lower-case) example for regular databases (MySQL, Postgresql, etc):
ActiveRecord::Base.establish_connection(
adapter: "mysql",
host: "localhost",
username: "myuser",
password: "mypass",
database: "somedatabase"
)
Example for SQLite database:
ActiveRecord::Base.establish_connection(
adapter: "sqlite3",
database: "path/to/dbfile"
)
Also accepts keys as strings (for parsing from YAML for example):
ActiveRecord::Base.establish_connection(
"adapter" => "sqlite3",
"database" => "path/to/dbfile"
)
Or a URL:
ActiveRecord::Base.establish_connection(
"postgres://myuser:mypass@localhost/somedatabase"
)
In case ActiveRecord::Base.configurations
is set (Rails automatically loads the contents of config/database.yml into it), a symbol can also be given as argument, representing a key in the configuration hash:
ActiveRecord::Base.establish_connection(:production)
The exceptions AdapterNotSpecified, AdapterNotFound and ArgumentError may be returned on an error.
# File activerecord/lib/active_record/connection_handling.rb, line 121
def remove_connection(klass = self)
connection_handler.remove_connection(klass)
end
# File activerecord/lib/active_record/connection_handling.rb, line 112
def retrieve_connection
connection_handler.retrieve_connection(self)
end
© 2004–2018 David Heinemeier Hansson
Licensed under the MIT License.