Class: Sequel::SchemaSharding::ConnectionManager

Inherits:
Object
  • Object
show all
Defined in:
lib/sequel/schema-sharding/connection_manager.rb

Overview

Used to manage database connections separately from database shards

Instance Attribute Summary collapse

Instance Method Summary collapse

Constructor Details

#initialize ⇒ ConnectionManager

Returns a new instance of ConnectionManager.



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# File 'lib/sequel/schema-sharding/connection_manager.rb', line 12

def initialize
  @connections = {}
end

Instance Attribute Details

#connections ⇒ Object (readonly)

Returns the value of attribute connections.



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# File 'lib/sequel/schema-sharding/connection_manager.rb', line 10

def connections
  @connections
end

Instance Method Details

#[](name) ⇒ Object 



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# File 'lib/sequel/schema-sharding/connection_manager.rb', line 16

def [](name)
  config = db_config_for(name)
  @connections[name.to_s] ||= Sequel.postgres(sequel_connection_config_for(config).merge!(replica_hash_for(config)))
end

#default_dataset_for(table_name) ⇒ Object

Given table_name, return a functional dataset. This is used when models are loaded to read table columns and allow for data typecasting. In most cases it should not be used directly in application code.



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# File 'lib/sequel/schema-sharding/connection_manager.rb', line 53

def default_dataset_for(table_name)
  shard_number = config.logical_shard_configs(table_name).keys.sample
  shard_name = config.logical_shard_configs(table_name)[shard_number]
  self[shard_name][:"#{schema_for(table_name, shard_number)}__#{table_name}"]
end

#disconnect ⇒ Object 



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# File 'lib/sequel/schema-sharding/connection_manager.rb', line 29

def disconnect
  @connections.each_value do |conn|
    conn.disconnect
  end
  @connections = {}
end

#master(name) ⇒ Object

Used by rake tasks that need to deterministically work against a master database even when read/write splitting is configured.



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# File 'lib/sequel/schema-sharding/connection_manager.rb', line 25

def master(name)
  @connections["master_#{name}"] ||= Sequel.postgres(sequel_connection_config_for(db_config_for(name)))
end

#schema_for(table_name, shard_number) ⇒ Object

Given table_name and shard_number, returns the name of the PostgreSQL schema based on a schema_name pattern defined in sharding.yml. shard_number is interpolated into schema_name via sprintf, so schema_name should include a format specifier with which to interpolate it (ex. %s, %02d).



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# File 'lib/sequel/schema-sharding/connection_manager.rb', line 43

def schema_for(table_name, shard_number)
  pattern = config.schema_name(table_name)
  sprintf pattern, shard_number
end