class Sequel::ConnectionPool

The base connection pool class, which all other connection pools are based on. This class is not instantiated directly, but subclasses should at the very least implement the following API:

initialize(Database, Hash)

Initialize using the passed Sequel::Database object and options hash.

hold(Symbol, &block)

Yield a connection object (obtained from calling the block passed to initialize) to the current block. For sharded connection pools, the Symbol passed is the shard/server to use.

disconnect(Symbol)

Disconnect the connection object. For sharded connection pools, the Symbol passed is the shard/server to use.

servers

An array of shard/server symbols for all shards/servers that this connection pool recognizes.

size

an integer representing the total number of connections in the pool, or for the given shard/server if sharding is supported.

max_size

an integer representing the maximum size of the connection pool, or the maximum size per shard/server if sharding is supported.

For sharded connection pools, the sharded API adds the following methods:

add_servers(Array of Symbols)

start recognizing all shards/servers specified by the array of symbols.

remove_servers(Array of Symbols)

no longer recognize all shards/servers specified by the array of symbols.

Constants

OPTS
POOL_CLASS_MAP

Attributes

after_connect[R]

The #after_connect proc used for this pool. This is called with each new connection made, and is usually used to set custom per-connection settings. Deprecated.

connect_sqls[R]

An array of sql strings to execute on each new connection. Deprecated.

db[RW]

The Sequel::Database object tied to this connection pool.

Public Class Methods

new(db, opts=OPTS) click to toggle source

Instantiates a connection pool with the given Database and options.

# File lib/sequel/connection_pool.rb, line 112
def initialize(db, opts=OPTS) # SEQUEL6: Remove second argument, always use db.opts
  @db = db
  @use_old_connect_api = false # SEQUEL6: Remove
  @after_connect = opts[:after_connect] # SEQUEL6: Remove
  @connect_sqls = opts[:connect_sqls] # SEQUEL6: Remove
  @error_classes = db.send(:database_error_classes).dup.freeze
end

Public Instance Methods

after_connect=(v) click to toggle source

Override the #after_connect proc for the connection pool. Deprecated. Disables support for shard-specific :after_connect and :connect_sqls if used.

# File lib/sequel/connection_pool.rb, line 93
def after_connect=(v) # SEQUEL6: Remove
  @use_old_connect_api = true
  @after_connect = v
end
connect_sqls=(v) click to toggle source

Override the #connect_sqls for the connection pool. Deprecated. Disables support for shard-specific :after_connect and :connect_sqls if used.

# File lib/sequel/connection_pool.rb, line 103
def connect_sqls=(v) # SEQUEL6: Remove
  @use_old_connect_api = true
  @connect_sqls = v
end
servers() click to toggle source

An array of symbols for all shards/servers, which is a single :default by default.

# File lib/sequel/connection_pool.rb, line 121
def servers
  [:default]
end

Private Instance Methods

disconnect_connection(conn) click to toggle source

Remove the connection from the pool. For threaded connections, this should be called without the mutex, because the disconnection may block.

# File lib/sequel/connection_pool.rb, line 129
def disconnect_connection(conn)
  db.disconnect_connection(conn)
end
disconnect_error?(exception) click to toggle source

Whether the given exception is a disconnect exception.

# File lib/sequel/connection_pool.rb, line 134
def disconnect_error?(exception)
  exception.is_a?(Sequel::DatabaseDisconnectError) || db.send(:disconnect_error?, exception, OPTS)
end
make_new(server) click to toggle source

Return a new connection by calling the connection proc with the given server name, and checking for connection errors.

# File lib/sequel/connection_pool.rb, line 140
def make_new(server)
  begin
    if @use_old_connect_api
      # SEQUEL6: Remove block
      conn = @db.connect(server)

      if ac = @after_connect
        if ac.arity == 2
          ac.call(conn, server)
        else
          ac.call(conn)
        end
      end

      if cs = @connect_sqls
        cs.each do |sql|
          db.send(:log_connection_execute, conn, sql)
        end
      end

      conn
    else
      @db.new_connection(server)
    end
  rescue Exception=>exception
    raise Sequel.convert_exception_class(exception, Sequel::DatabaseConnectionError)
  end || raise(Sequel::DatabaseConnectionError, "Connection parameters not valid")
end