Module: Semian::Mysql2

Includes:
Adapter
Defined in:
lib/semian/mysql2.rb

Constant Summary collapse

CONNECTION_ERROR = 
Regexp.union(
  /Can't connect to MySQL server on/i,
  /Lost connection to MySQL server/i,
  /MySQL server has gone away/i,
  /Too many connections/i,
)
ResourceBusyError = 
::Mysql2::ResourceBusyError
CircuitOpenError = 
::Mysql2::CircuitOpenError
PingFailure = 
Class.new(::Mysql2::Error)
DEFAULT_HOST = 
'localhost'
DEFAULT_PORT = 
3306
QUERY_WHITELIST = 
Regexp.union(
  /\A\s*ROLLBACK/i,
  /\A\s*COMMIT/i,
  /\A\s*RELEASE\s+SAVEPOINT/i,
)

Class Method Summary collapse

Instance Method Summary collapse

Methods included from Adapter

#semian_resource

Class Method Details

.included(base) ⇒ Object

The naked methods are exposed as ‘raw_query` and `raw_connect` for instrumentation purpose



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# File 'lib/semian/mysql2.rb', line 43

def self.included(base)
  base.send(:alias_method, :raw_query, :query)
  base.send(:remove_method, :query)

  base.send(:alias_method, :raw_connect, :connect)
  base.send(:remove_method, :connect)

  base.send(:alias_method, :raw_ping, :ping)
  base.send(:remove_method, :ping)
end

Instance Method Details

#ping ⇒ Object 



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# File 'lib/semian/mysql2.rb', line 65

def ping
  result = nil
  acquire_semian_resource(adapter: :mysql, scope: :ping) do
    result = raw_ping
    raise PingFailure.new(result.to_s) unless result
  end
  result
rescue ResourceBusyError, CircuitOpenError, PingFailure
  false
end

#query(*args) ⇒ Object 



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# File 'lib/semian/mysql2.rb', line 76

def query(*args)
  if query_whitelisted?(*args)
    raw_query(*args)
  else
    acquire_semian_resource(adapter: :mysql, scope: :query) { raw_query(*args) }
  end
end

#semian_identifier ⇒ Object 



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# File 'lib/semian/mysql2.rb', line 54

def semian_identifier
  @semian_identifier ||= begin
    unless name = semian_options && semian_options[:name]
      host = query_options[:host] || DEFAULT_HOST
      port = query_options[:port] || DEFAULT_PORT
      name = "#{host}:#{port}"
    end
    :"mysql_#{name}"
  end
end