fix(retry): better error

lib/algolia/logger_helper.rb

@@ -5,7 +5,7 @@ class LoggerHelper
     # @param debug_file [nil|String] file used to output the logs
     #
     def self.create(debug_file = nil)
-      file              = debug_file || (ENV['ALGOLIA_DEBUG'] ? File.new('debug.log') : $stderr)
+      file              = debug_file || (ENV['ALGOLIA_DEBUG'] ? File.open('debug.log', 'a+') : $stderr)
       instance          = ::Logger.new file
       instance.progname = 'algolia'
       instance

lib/algolia/transport/retry_strategy.rb

@@ -1,6 +1,6 @@
 module Algolia
   module Transport
-    # Class RetryStatregy
+    # Class RetryStrategy
     class RetryStrategy
       include RetryOutcomeType
 

lib/algolia/transport/transport.rb

@@ -49,6 +49,8 @@ def write(method, path, body = {}, opts = {})
       # @return [Response] response of the request
       #
       def request(call_type, method, path, body = {}, opts = {})
+        last_retry = {host: nil, error: nil}
+
         @retry_strategy.get_tryable_hosts(call_type).each do |host|
           opts[:timeout]         ||= get_timeout(call_type) * (host.retry_count + 1)
           opts[:connect_timeout] ||= @config.connect_timeout * (host.retry_count + 1)
@@ -73,10 +75,14 @@ def request(call_type, method, path, body = {}, opts = {})
             decoded_error = json_to_hash(response.error, @config.symbolize_keys)
             raise AlgoliaHttpError.new(get_option(decoded_error, 'status'), get_option(decoded_error, 'message'))
           end
-          return json_to_hash(response.body, @config.symbolize_keys) unless outcome == RETRY
+          if outcome == RETRY
+            last_retry = {host: host.url, error: response.error}
+          else
+            return json_to_hash(response.body, @config.symbolize_keys)
+          end
         end
 
-        raise AlgoliaUnreachableHostError, 'Unreachable hosts'
+        raise AlgoliaUnreachableHostError, "Unreachable hosts. Last error for #{last_retry[:host]}: #{last_retry[:error]}"
       end
 
       private

test/algolia/unit/retry_strategy_test.rb

@@ -82,11 +82,11 @@ def test_failure_when_all_hosts_are_down
         index.save_object({ objectID: 'one' })
       end
 
-      assert_equal 'Unreachable hosts', exception.message
+      assert_includes exception.message, 'Unreachable hosts. Last error for 0.0.0.0: SSL_connect'
     end
   end
 
-  describe 'retry stategy decisions' do
+  describe 'retry strategy decisions' do
     def before_all
       super
       @app_id         = 'app_id'