retries.rb in httpx-0.23.0

- old
+ new

@@ -9,11 +9,11 @@
     #
     module Retries
       MAX_RETRIES = 3
       # TODO: pass max_retries in a configure/load block
 
-      IDEMPOTENT_METHODS = %i[get options head put delete].freeze
+      IDEMPOTENT_METHODS = %w[GET OPTIONS HEAD PUT DELETE].freeze
       RETRYABLE_ERRORS = [
         IOError,
         EOFError,
         Errno::ECONNRESET,
         Errno::ECONNABORTED,
@@ -94,11 +94,11 @@
                (
                  response.is_a?(ErrorResponse) && __retryable_error?(response.error)
                )
                # rubocop:enable Style/MultilineTernaryOperator
              )
-            response.close if response.respond_to?(:close)
+            __try_partial_retry(request, response)
             log { "failed to get response, #{request.retries} tries to go..." }
             request.retries -= 1
             request.transition(:idle)
 
             retry_after = options.retry_after
@@ -132,17 +132,64 @@
         end
 
         def __retryable_error?(ex)
           RETRYABLE_ERRORS.any? { |klass| ex.is_a?(klass) }
         end
+
+        #
+        # Atttempt to set the request to perform a partial range request.
+        # This happens if the peer server accepts byte-range requests, and
+        # the last response contains some body payload.
+        #
+        def __try_partial_retry(request, response)
+          response = response.response if response.is_a?(ErrorResponse)
+
+          return unless response
+
+          unless response.headers.key?("accept-ranges") &&
+                 response.headers["accept-ranges"] == "bytes" && # there's nothing else supported though...
+                 (original_body = response.body)
+            response.close if response.respond_to?(:close)
+            return
+          end
+
+          request.partial_response = response
+
+          size = original_body.bytesize
+
+          request.headers["range"] = "bytes=#{size}-"
+        end
       end
 
       module RequestMethods
         attr_accessor :retries
 
+        attr_writer :partial_response
+
         def initialize(*args)
           super
           @retries = @options.max_retries
+        end
+
+        def response=(response)
+          if @partial_response
+            if response.is_a?(Response) && response.status == 206
+              response.from_partial_response(@partial_response)
+            else
+              @partial_response.close
+            end
+            @partial_response = nil
+          end
+
+          super
+        end
+      end
+
+      module ResponseMethods
+        def from_partial_response(response)
+          @status = response.status
+          @headers = response.headers
+          @body = response.body
         end
       end
     end
     register_plugin :retries, Retries
   end