Support with_meta without transactions about logidze

[oleg-kiviljov]

Hi @palkan, are there any ideas how this could be implemented?

[palkan]

I have one idea which could described as follows:

# add an option to specify whether we want a transaction or not 
# (this is mostly for backward compatibility)
def with_meta(data, transactional: true, &block)
  #  transactional_with_meta is the current implementation
  return MetaTransaction.wrap(data, &block) if transactional

  MetaNoTransaction.wrap(data, &block)
end

# the same as current MetaTransaction with the only one change
class Meta
  def perform
    raise ArgumentError, "Block must be given" unless block

    call_block_in_meta_context
  end

  def call_block_in_meta_context
    prev_meta = current_meta

    meta_stack.push(meta)

    pg_set_meta_param(current_meta)
    result = block.call

    result
  ensure
    # That's the only difference: we move reset to ensure to call it in case of exceptions
    pg_reset_meta_param(prev_meta)
    meta_stack.pop
  end
end

class MetaTransaction < BaseMeta
  def  call_block_in_meta_context
    ActiveRecord::Base.transaction { super }
  end
end

I hope, that should be enough)

[oleg-kiviljov]

Hi @palkan, I don't really get how the SET LOCAL is done without transaction based on your example.

[palkan]

Yeah, there is the point missing; when we're not within a transaction, we can only use SET (w/o LOCAL); and that's why we have to cleanup manually.

[palkan]

Closed by #143