Class: Simple::SQL::Connection::RawConnection

Inherits:
Simple::SQL::Connection show all
Defined in:
lib/simple/sql/connection/raw_connection.rb

Constant Summary collapse

SELF = 
self

Constants included from Simple::SQL::ConnectionAdapter

Simple::SQL::ConnectionAdapter::Logging, Simple::SQL::ConnectionAdapter::Scope

Instance Attribute Summary collapse

Class Method Summary collapse

Instance Method Summary collapse

Methods inherited from Simple::SQL::Connection

create, #duplicate, #insert, #reflection

Methods included from Simple::SQL::ConnectionAdapter

#all, #ask, #costs, #each, #exec, #locked, #print, #resolve_type

Constructor Details

#initialize(database_url) ⇒ RawConnection

Returns a new instance of RawConnection.



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# File 'lib/simple/sql/connection/raw_connection.rb', line 8

def initialize(database_url)
  @database_url = database_url
  @raw_connection = PG::Connection.new(@database_url)
  ObjectSpace.define_finalizer(self, SELF.finalizer(@raw_connection))
end

Instance Attribute Details

#raw_connection ⇒ Object (readonly)

Returns the value of attribute raw_connection.



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# File 'lib/simple/sql/connection/raw_connection.rb', line 6

def raw_connection
  @raw_connection
end

Class Method Details

.finalizer(raw_connection) ⇒ Object 



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# File 'lib/simple/sql/connection/raw_connection.rb', line 14

def self.finalizer(raw_connection)
  proc do
    raw_connection.finish unless raw_connection.finished?
  end
end

Instance Method Details

#disconnect! ⇒ Object 



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# File 'lib/simple/sql/connection/raw_connection.rb', line 20

def disconnect!
  return unless @raw_connection

  @raw_connection.finish unless @raw_connection.finished?
  @raw_connection = nil
end

#transaction(&_block) ⇒ Object 



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# File 'lib/simple/sql/connection/raw_connection.rb', line 27

def transaction(&_block)
  @tx_nesting_level ||= 0

  # Notes: by using "ensure" (as opposed to rescue) we are rolling back
  # both when an exception was raised and when a value was thrown. This
  # also means we have to track whether or not to rollback. i.e. do roll
  # back when we yielded to &block but not otherwise.
  #
  # Also the transaction support is a bit limited: you cannot rollback.
  # Rolling back from inside a nested transaction would require SAVEPOINT
  # support; without the code is simpler at least :)

  if @tx_nesting_level == 0
    exec "BEGIN"
    tx_started = true
  end

  @tx_nesting_level += 1

  return_value = yield

  # Only commit if we started a transaction here.
  if tx_started
    exec "COMMIT"
    tx_committed = true
  end

  return_value
ensure
  @tx_nesting_level -= 1
  if tx_started && !tx_committed
    exec "ROLLBACK"
  end
end