Improve socket management for EiffelWeb standalone connector.

examples/simple/application_execution.e

@@ -24,6 +24,8 @@ feature -- Basic operations
  			s := "Hello World!"
 			create dt.make_now_utc
 			s.append (" (UTC time is " + dt.rfc850_string + ").")
+			s.append ("%N")
+			s.append ("Your request: " + request.request_uri + " %N")
 			response.put_header ({HTTP_STATUS_CODE}.ok, <<["Content-Type", "text/html"], ["Content-Length", s.count.out]>>)
 			response.set_status_code ({HTTP_STATUS_CODE}.ok)
 			response.header.put_content_type_text_html

library/server/ewsgi/connectors/standalone/lib/httpd/httpd_request_handler_i.e

@@ -33,7 +33,7 @@ feature {NONE} -- Initialization
 		do
 			reset_request
 
-			has_error := False
+			reset_error
 			if attached internal_client_socket as l_sock then
 				l_sock.cleanup
 			end
@@ -156,6 +156,20 @@ feature -- Status report
 	has_error: BOOLEAN
 			-- Error occurred during `analyze_request_message'
 
+feature -- Status change
+
+	report_error (m: detachable READABLE_STRING_GENERAL)
+			-- Report error occurred, with optional message `m'.
+		do
+			has_error := True
+		end
+
+	reset_error
+			-- Reset previous error for current request handler.
+		do
+			has_error := False
+		end
+
 feature -- Change
 
 	set_is_verbose (b: BOOLEAN)
@@ -236,11 +250,18 @@ feature -- Execution
 		require
 			is_connected: is_connected
 			reuse_connection_when_possible: a_is_reusing_connection implies is_persistent_connection_supported
+			no_error: not has_error
 		local
 			l_remote_info: detachable like remote_info
 			l_socket: like client_socket
 			l_is_ready: BOOLEAN
 		do
+			debug ("dbglog")
+				if a_is_reusing_connection then
+					dbglog ("execute_request: wait on persistent connection.")
+				end
+			end
+			reset_error
 			l_socket := client_socket
 			check
 				socket_attached: l_socket /= Void
@@ -248,17 +269,18 @@ feature -- Execution
 			end
 			if l_socket.is_closed then
 				debug ("dbglog")
-					dbglog (generator + ".execute_request {socket is Closed!}")
+					dbglog ("execute_request {socket is Closed!}")
 				end
 			else
 				debug ("dbglog")
-					dbglog (generator + ".execute_request  socket=" + l_socket.descriptor.out + " ENTER")
+					dbglog ("execute_request  socket=" + l_socket.descriptor.out + " ENTER")
 				end
 
 				if a_is_reusing_connection then
 						--| set by default 5 seconds.
 					l_socket.set_recv_timeout (keep_alive_timeout) -- in seconds!
-					l_is_ready := l_socket.ready_for_reading
+						-- FIXME: check if both are really needed.
+					l_is_ready := l_socket.ready_for_reading and then l_socket.has_incoming_data
 				else
 					l_is_ready := True
 				end
@@ -273,20 +295,12 @@ feature -- Execution
 						remote_info := l_remote_info
 					end
             		analyze_request_message (l_socket)
-            	else
-					has_error := True
-					debug ("dbglog")
-						dbglog (generator + ".execute_request socket=" + l_socket.descriptor.out + "} timeout!")
-	            	end
-				end
 
             		if has_error then
-					if l_is_ready then
 	--					check catch_bad_incoming_connection: False end
 						if is_verbose then
 							log (request_header + "%NWARNING: invalid HTTP incoming request", warning_level)
 						end
-					end
 						process_bad_request (l_socket)
 						is_persistent_connection_requested := False
 					else
@@ -295,8 +309,17 @@ feature -- Execution
 						end
 						process_request (l_socket)
 		            end
+            	else
+            		check is_reusing_connection: a_is_reusing_connection end
+            			-- Close persistent connection, since no new connection occurred in the delay `keep_alive_timeout'.
+            		is_persistent_connection_requested := False
 					debug ("dbglog")
-		            dbglog (generator + ".execute_request {" + l_socket.descriptor.out + "} LEAVE")
+						dbglog ("execute_request socket=" + l_socket.descriptor.out + "} close persistent connection.")
+	            	end
+				end
+
+	            debug ("dbglog")
+		            dbglog ("execute_request {" + l_socket.descriptor.out + "} LEAVE")
 	            end
 			end
 		end
@@ -329,6 +352,8 @@ feature -- Request processing
 			h: STRING
 			s: STRING
 		do
+				-- NOTE: this is experiment code, and not ready yet.
+			if a_socket.is_connected and then a_socket.ready_for_writing then
 				s := "{
 <!DOCTYPE HTML PUBLIC "-//IETF//DTD HTML 2.0//EN">
 <html><head>
@@ -344,8 +369,11 @@ feature -- Request processing
 				h.append ("Content-Type: text/html; charset=iso-8859-1%R%N")
 				h.append ("%R%N")
 				a_socket.put_string (h)
+				if a_socket.is_connected and then a_socket.ready_for_writing then
 					a_socket.put_string (s)
 				end
+			end
+		end
 
 feature -- Parsing
 
@@ -365,7 +393,12 @@ feature -- Parsing
 			request_header := txt
 			if
 				not has_error and then
-				a_socket.is_readable and then
+				a_socket.readable
+			then
+				if not a_socket.has_incoming_data then
+					dbglog ("analyze_request_message: NO INCOMING DATA !!!")
+				end
+				if
 					attached next_line (a_socket) as l_request_line and then
 					not l_request_line.is_empty
 				then
@@ -373,7 +406,10 @@ feature -- Parsing
 					txt.append_character ('%N')
 					analyze_request_line (l_request_line)
 				else
-				has_error := True
+					report_error ("Bad header line (empty)")
+				end
+			else
+				report_error ("Socket is not readable")
 			end
 			l_is_verbose := is_verbose
 			if not has_error then
@@ -448,7 +484,9 @@ feature -- Parsing
 				n := n - 1
 			end
 			version := line.substring (next_pos + 1, n)
-			has_error := method.is_empty
+			if method.is_empty then
+				report_error ("Missing request method data")
+			end
 		end
 
 	next_line (a_socket: HTTPD_STREAM_SOCKET): detachable STRING
@@ -460,7 +498,7 @@ feature -- Parsing
 			retried: BOOLEAN
 		do
 			if retried then
-				has_error := True
+				report_error ("Rescue in next_line")
 				Result := Void
 			elseif a_socket.readable then
 				a_socket.read_line_thread_aware
@@ -468,14 +506,14 @@ feature -- Parsing
 					-- Do no check `socket_ok' before socket operation,
 					-- otherwise it may be False, due to error during other socket operation in same thread.
 				if not a_socket.socket_ok then
-					has_error := True
+					report_error ("Socket error")
 					if is_verbose then
 						log (request_header +"%N" + Result + "%N## socket_ok=False! ##", debug_level)
 					end
 				end
 			else
 					-- Error with socket...
-				has_error := True
+				report_error ("Socket error: not readable")
 				if is_verbose then
 					log (request_header + "%N## Socket is not readable! ##", debug_level)
 				end

library/server/ewsgi/connectors/standalone/lib/httpd/network/httpd_stream_socket.e

@@ -141,6 +141,15 @@ feature -- Input
 			socket.read_character
 		end
 
+	peek_stream (nb_char: INTEGER)
+		require
+			nb_char_positive: nb_char > 0
+		do
+			if attached {TCP_STREAM_SOCKET} socket as l_socket then
+				l_socket.peek_stream (nb_char)
+			end
+		end
+
 	bytes_read: INTEGER
 		do
 			Result := socket.bytes_read
@@ -308,6 +317,13 @@ feature -- Status Report
 			Result := socket.readable
 		end
 
+	has_incoming_data: BOOLEAN
+		do
+			if attached {TCP_STREAM_SOCKET} socket as l_socket then
+				Result := l_socket.has_incoming_data
+			end
+		end
+
 	ready_for_reading: BOOLEAN
 		do
 			if attached {TCP_STREAM_SOCKET} socket as l_socket then

library/server/ewsgi/connectors/standalone/lib/httpd/network/tcp_stream_socket.e

@@ -55,6 +55,38 @@ feature {NONE} -- Initialization
 
 feature -- Basic operation
 
+	peek_stream (nb_char: INTEGER)
+			-- Read a string of at most `nb_char' characters without removing the data from the queue.
+			-- Make result available in last_string.
+		require
+			readable: readable
+			socket_exists: exists
+		local
+			ext: C_STRING
+			retval: INTEGER
+			l: like last_string
+		do
+			create ext.make_empty (nb_char + 1)
+			retval := c_receive (descriptor, ext.item, nb_char, c_peekmsg)
+			if retval = 0 then
+				last_string.wipe_out
+				socket_error := Void
+			elseif retval > 0 then
+				ext.set_count (retval)
+				l := last_string
+				l.wipe_out
+				l.grow (retval)
+				l.set_count (retval)
+				ext.read_substring_into (l, 1, retval)
+				socket_error := Void
+			else
+				last_string.wipe_out
+				socket_error := "Socket error (MSG_PEEK)"
+			end
+		ensure
+			last_string_not_void: last_string /= Void
+		end
+
 	send_message (a_msg: STRING)
 		do
 			put_string (a_msg)
@@ -73,6 +105,14 @@ feature -- Output
 
 feature -- Status report
 
+	has_incoming_data: BOOLEAN
+		require
+			socket_exists: exists
+		do
+			peek_stream (1)
+			Result := last_string.count = 1
+		end
+
 	try_ready_for_reading: BOOLEAN
 			-- Is data available for reading from the socket right now?
 		require

library/server/ewsgi/connectors/standalone/src/implementation/wgi_httpd_request_handler.e

@@ -97,7 +97,9 @@ feature -- Request processing
 				end
 			end
 		rescue
-			has_error := l_output = Void or else not l_output.is_available
+			if l_output = Void or else not l_output.is_available then
+				report_error ("Missing WGI output")
+			end
 			if not retried then
 				retried := True
 				retry