From bbe4813c083bf95ebe7a5a6dbb519f808ba2ab98 Mon Sep 17 00:00:00 2001
From: Adam McCrea <adam@adamlogic.com>
Date: Sat, 11 Mar 2023 09:22:04 -0500
Subject: [PATCH] fix: Gracefully handle several types of transient TCP errors

---
 judoscale-ruby/lib/judoscale/adapter_api.rb | 12 ++++++++++--
 judoscale-ruby/test/adapter_api_test.rb     |  2 +-
 2 files changed, 11 insertions(+), 3 deletions(-)

diff --git a/judoscale-ruby/lib/judoscale/adapter_api.rb b/judoscale-ruby/lib/judoscale/adapter_api.rb
index 8da70461..649ba6df 100644
--- a/judoscale-ruby/lib/judoscale/adapter_api.rb
+++ b/judoscale-ruby/lib/judoscale/adapter_api.rb
@@ -10,6 +10,14 @@ class AdapterApi
     include Logger
 
     SUCCESS = "success"
+    TRANSIENT_ERRORS = [
+      Errno::ECONNREFUSED,
+      Errno::ECONNRESET,
+      Net::OpenTimeout,
+      Net::ReadTimeout,
+      OpenSSL::SSL::SSLError,
+    ]
+
 
     def initialize(config)
       @config = config
@@ -43,14 +51,14 @@ def post_raw(options)
       when 200...300 then SuccessResponse.new(response.body)
       else FailureResponse.new([response.code, response.message].join(" - "))
       end
-    rescue Net::OpenTimeout
+    rescue *TRANSIENT_ERRORS => ex
       if attempts < 3
         # TCP timeouts happen sometimes, but they can usually be successfully retried in a moment
         sleep 0.01
         attempts += 1
         retry
       else
-        FailureResponse.new("Timeout while obtaining TCP connection to #{uri.host}")
+        FailureResponse.new("Could not connect to #{uri.host}: #{ex.inspect}")
       end
     end
 
diff --git a/judoscale-ruby/test/adapter_api_test.rb b/judoscale-ruby/test/adapter_api_test.rb
index 1e1ca6d6..c1abe850 100644
--- a/judoscale-ruby/test/adapter_api_test.rb
+++ b/judoscale-ruby/test/adapter_api_test.rb
@@ -57,7 +57,7 @@
       result = adapter_api.report_metrics(report_params)
 
       _(result).must_be_instance_of Judoscale::AdapterApi::FailureResponse
-      _(result.failure_message).must_equal "Timeout while obtaining TCP connection to railsautoscale.dev"
+      _(result.failure_message).must_equal "Could not connect to railsautoscale.dev: #<Net::OpenTimeout: execution expired>"
       assert_requested stub, times: 3
     end