lib/httpx/resolver/native.rb in httpx-1.2.4 vs lib/httpx/resolver/native.rb in httpx-1.2.6

@@ -63,10 +63,11 @@
       @ns_index += 1
       nameserver = @nameserver
       if nameserver && @ns_index < nameserver.size
         log { "resolver: failed resolving on nameserver #{@nameserver[@ns_index - 1]} (#{e.message})" }
         transition(:idle)
+        @timeouts.clear
       else
         handle_error(e)
       end
     rescue NativeResolveError => e
       handle_error(e)
@@ -141,17 +142,20 @@
 
       @timeouts[host].shift
 
       if !@timeouts[host].empty?
         log { "resolver: timeout after #{timeout}s, retry(#{@timeouts[host].first}) #{host}..." }
-        resolve(connection)
+        # must downgrade to tcp AND retry on same host as last
+        downgrade_socket
+        resolve(connection, h)
       elsif @ns_index + 1 < @nameserver.size
         # try on the next nameserver
         @ns_index += 1
         log { "resolver: failed resolving #{host} on nameserver #{@nameserver[@ns_index - 1]} (timeout error)" }
         transition(:idle)
-        resolve(connection)
+        @timeouts.clear
+        resolve(connection, h)
       else
 
         @timeouts.delete(host)
         reset_hostname(h, reset_candidates: false)
 
@@ -185,14 +189,13 @@
             @large_packet << @read_buffer
 
             next unless @large_packet.full?
 
             parse(@large_packet.to_s)
-            @socket_type = @resolver_options.fetch(:socket_type, :udp)
             @large_packet = nil
-            transition(:idle)
-            transition(:open)
+            # downgrade to udp again
+            downgrade_socket
             return
           else
             size = @read_buffer[0, 2].unpack1("n")
             buffer = @read_buffer.byteslice(2..-1)
 
@@ -302,17 +305,25 @@
           address["name"] = name
           connection = @queries.delete(name)
         end
 
         if address.key?("alias") # CNAME
+          hostname_alias = address["alias"]
           # clean up intermediate queries
           @timeouts.delete(name) unless connection.origin.host == name
 
-          if catch(:coalesced) { early_resolve(connection, hostname: address["alias"]) }
+          if catch(:coalesced) { early_resolve(connection, hostname: hostname_alias) }
             @connections.delete(connection)
           else
-            resolve(connection, address["alias"])
+            if @socket_type == :tcp
+              # must downgrade to udp if tcp
+              @socket_type = @resolver_options.fetch(:socket_type, :udp)
+              transition(:idle)
+              transition(:open)
+            end
+            log { "resolver: ALIAS #{hostname_alias} for #{name}" }
+            resolve(connection, hostname_alias)
             return
           end
         else
           reset_hostname(name, connection: connection)
           @timeouts.delete(connection.origin.host)
@@ -384,17 +395,24 @@
         origin = URI("tcp://#{ip}:#{port}")
         TCP.new(origin, [ip], @options)
       end
     end
 
+    def downgrade_socket
+      return unless @socket_type == :tcp
+
+      @socket_type = @resolver_options.fetch(:socket_type, :udp)
+      transition(:idle)
+      transition(:open)
+    end
+
     def transition(nextstate)
       case nextstate
       when :idle
         if @io
           @io.close
           @io = nil
         end
-        @timeouts.clear
       when :open
         return unless @state == :idle
 
         @io ||= build_socket