"read would block" when communicating with external APIs

[gillesbergerp]

Basic Info

• Faraday Version: 2.11.0
• Ruby Version: jruby 9.4.8.0 (3.1.4) 2024-07-02 4d41e55a67 OpenJDK 64-Bit Server VM 21.0.4+7-LTS on 21.0.4+7-LTS +jit [x86_64-linux]

Issue description

We occasionally and intermittently face Faraday::SSLErrors with the message read would block when communicating with external endpoints. Our application is deployed as an ECS on EC2 service and (so far) we were unable to reproduce the issue locally or in our staging environment. We use jruby-openssl on version 0.15.0.

Steps to reproduce

Unfortunately, we haven't managed to reproduce the issue locally. There are certain requests to external APIs that fail very consistently, however.

[iMacTia]

Sorry for the delay getting back to you @gillesbergerp, I wanted to at least try and be useful but:

1. I have close to zero experience with JRuby
2. I have never seen that error on MRI Ruby

For what I know, this error may be bound to a much lower layer than Faraday (e.g. could this be related?).

I'm not really sure on how to proceed, but maybe changing the adapter to another JRuby-compatible adapter could provide some useful data?

[olleolleolle]

"read would block" is indeed raised by that JRuby gem:

https://github.com/jruby/jruby-openssl/blob/7767343f269b5761380d293b8419f4a5748cf201/src/main/java/org/jruby/ext/openssl/SSLSocket.java#L545