end of file reached EOFError (Databasedotcom + Rails + Heroku)

Question

After much frustration trying to figure it out myself, I am reaching for SO guys (you!) to help me trace this formidable error:

Message: end of file reached EOFError Backtrace: ["/app/vendor/ruby-1.9.3/lib/ruby/1.9.1/openssl/buffering.rb:174:in `sysread_nonblock

Background : My App is a Rails 3 app hosted on Heroku and 100% back-end app. It uses Redis/Resque workers to process it's payload received from Salesforce using Chatter REST API.

Trouble : Unlike other similar errors of EOF in HTTPS/OpenSSL in Ruby, my error happens very random (since I can't yet predict when will this come up).

Usual Suspects : The error has been noticed quite frequently when I try to create 45 Resque workers, and try to sync data from 45 different Salesforce Chatter REST API connections all at once! It's so frequent that my processing fails 20% or more of the total and all due to this error.

Remedy Steps : I am using Databasedotcom gem which uses HTTPS and follows all the required steps to connect to create a sane HTTPS connection. So...

• Use SSL set in HTTPS - checked
• URI Encode - checked
• Ruby 1.9.3 - checked
• HTTP read timeout is set to 900 (15 minutes)
• I retry this EOF error MAX of 30 times after sleeping 30 seconds before each retry! Still, it fails some of the data.

Any help here please?

Answer 1

Have you considered that Salesforce might not like so many connections at once from a single source and you are blocked by an DDOS-preventer?

Also, setting those long timeouts is quite useless. If the connection fails, drop it and reschedule a new one yourself. That is what Resque does fine, it will add up those waiting times if it keeps having problems...