EventMachine not catching nearly simultaneous events - ruby

Question

I'm using EventMachine to process incoming emails which could at times be very high volume. The code that I have so far definitely works for emails that come in separated by at least about 5 seconds, but somewhere below that, only one email will be processed out of however many arrive. I've tried adding EM.defer statements in a few different places which I thought would help, but to no avail. I should also note, if it makes any difference, that I'm using the em-imap gem in this example as well.
The relevant section of the code is here:
EM.run do
client = EM::IMAP.new('imap.gmail.com', 993, true)
client.connect.bind! do
client.login('me#email.com', 'password123')
end.bind! do
client.select('INBOX')
end.bind! do
client.wait_for_new_emails do |response|
client.fetch(response.data).callback do |fetched|
currentSubjectLine = fetched.first.attr.values[1].subject
desiredCommand = parseSubjectLine(currentSubjectLine)
if desiredCommand == 0
if fetched.first.attr.values[0].parts.length == 2
if fetched.first.attr.values[0].parts[1].subtype.downcase != "pdf"
puts 'Error: Missing attachment, or attachment of the wrong type.'
else
file_name = fetched.first.attr.values[0].parts[1].param.values[0]
client.fetch(response.data, "BODY[2]").callback do |attachments|
attachment = attachments[0].attr["BODY[2]"]
File.new(file_name,'wb+').write(Base64.decode64(attachment))
end
end...
Am I somehow blocking the reactor in this code segment? Is it possible that some library that I'm using isn't appropriate here? Could GMail's IMAP server have something to do with it? Do you need any more information about what happens in some given situation before you can answer with confidence? As always, any help is greatly appreciated. Thank you!
Update with Minimized Code
Just in case anything in my organization has anything to do with it, I'm including everything that I think might possibly be relevant.
module Processing
def self.run
EM.run do
client = EM::IMAP.new('imap.gmail.com', 993, true)
client.connect.bind! do
client.login('me#email.com', 'password123')
end.bind! do
client.select('INBOX')
end.bind! do
client.wait_for_new_emails do |response|
client.fetch(response.data).callback do |fetched|
puts fetched[0].attr.values[1].subject
end
end
end.errback do |error|
puts "Something failed: #{error}"
end
end...
Processing.run

Answer 1

Don't hate me for saying this, but refactor that pyramid of doom spaggheti thingy that makes Demeter twitch into something readable and the error will reveal itself :)
If it doesn't reveal itself you will be able to boil it down to the simplest possible code that reproduces the problem and submit it as an issue to https://github.com/eventmachine/eventmachine
However, EM isn't really supported any more, the devs went a bit awol so think about moving to https://github.com/celluloid/celluloid and https://github.com/celluloid/celluloid-io
PS
just saw this
File.new(file_name,'wb+').write(Base64.decode64(attachment))
is a blocking call afaik, try playing with this and you might be able to reproduce the issue. See https://github.com/martinkozak/em-files and http://eventmachine.rubyforge.org/EventMachine.html#defer-class_method on possible ways to go around this