Added connection header related functions.

- WSF_REQUEST.is_keep_alive_http_connection: BOOLEAN
  - HTTP_HEADER_MODIFIER.put_connection_keep_alive
  - HTTP_HEADER_MODIFIER.put_connection_close
In Standalone request handler code, better detection of Connection: keep-alive header.

library/network/protocol/http/src/http_header_modifier.e

@@ -544,6 +544,26 @@ feature -- Others
 			put_pragma ("no-cache")
 		end
 
+feature -- Connection		
+
+	put_connection (a_conn: READABLE_STRING_8)
+			-- Put "Connection" header with `a_conn' value.
+		do
+			put_header_key_value ({HTTP_HEADER_NAMES}.header_connection, a_conn)
+		end
+
+	put_connection_keep_alive
+			-- Put "Connection" header with "keep-alive".
+		do
+			put_connection ("keep-alive")
+		end
+
+	put_connection_close
+			-- Put "Connection" header with "close".
+		do
+			put_connection ("close")
+		end
+
 feature -- Redirection
 
 	put_location (a_uri: READABLE_STRING_8)

library/server/httpd/httpd_request_handler_i.e

@@ -455,14 +455,11 @@ feature -- Parsing
 							-- Except for HTTP/1.0, persistent connection is the default.
 						is_persistent_connection_requested := True
 						if is_http_version_1_0 then
-							is_persistent_connection_requested := attached request_header_map.item ("Connection") as l_connection and then
-										l_connection.is_case_insensitive_equal_general ("keep-alive")
+							is_persistent_connection_requested := has_keep_alive_http_connection_header (request_header_map)
 						else
 								-- By default HTTP:1/1 support persistent connection.
-							if attached request_header_map.item ("Connection") as l_connection then
-								if l_connection.is_case_insensitive_equal_general ("close") then
-									is_persistent_connection_requested := False
-								end
+							if has_close_http_connection_header (request_header_map) then
+								is_persistent_connection_requested := False
 							else
 								is_persistent_connection_requested := True
 							end
@@ -476,6 +473,46 @@ feature -- Parsing
 			end
 		end
 
+	has_keep_alive_http_connection_header (h_map: like request_header_map): BOOLEAN
+			-- Does Current request header map `h_map' have "keep-alive" connection header?
+		local
+			i: INTEGER
+		do
+			if attached h_map.item ("Connection") as l_connection then
+					-- Could be for instance "keep-alive, Upgrade"
+				i := l_connection.substring_index ("keep-alive", 1)
+				if i > 0 then
+					i := i + 9 -- "keep-alive" has 10 characters
+					check i <= l_connection.count end
+					if i = l_connection.count then
+						Result := True
+					else
+						Result := l_connection [i + 1] = ',' or l_connection [i + 1].is_space
+					end
+				end
+			end
+		end
+
+	has_close_http_connection_header (h_map: like request_header_map): BOOLEAN
+			-- Does Current request header map `h_map' have "close" connection header?
+		local
+			i: INTEGER
+		do
+			if attached h_map.item ("Connection") as l_connection then
+					-- Could be for instance "close, ..."
+				i := l_connection.substring_index ("close", 1)
+				if i > 0 then
+					i := i + 4 -- "close" has 5 characters
+					check i <= l_connection.count end
+					if i = l_connection.count then
+						Result := True
+					else
+						Result := l_connection [i + 1] = ',' or l_connection [i + 1].is_space
+					end
+				end
+			end
+		end
+
 	analyze_request_line (line: STRING)
 			-- Analyze `line' as a HTTP request line.
 			-- note: may update `has_error'.

library/server/wsf/src/wsf_request.e

@@ -1200,11 +1200,19 @@ feature -- HTTP_*
 
 	http_connection: detachable READABLE_STRING_8
 			-- Contents of the Connection: header from the current wgi_request, if there is one.
-			-- Example: 'Keep-Alive'.
+			-- Example: 'keep-alive'.
 		do
 			Result := wgi_request.http_connection
 		end
 
+	is_keep_alive_http_connection: BOOLEAN
+			-- Is a keep-alive connection?
+		do
+			if attached http_connection as conn then
+				Result := conn.starts_with ("keep-alive")
+			end
+		end
+
 	http_expect: detachable READABLE_STRING_8
 			-- The Expect request-header field is used to indicate that particular server behaviors are required by the client.
 			-- Example: '100-continue'.

library/server/wsf_proxy/reverse_proxy/wsf_simple_reverse_proxy_handler.e

@@ -291,11 +291,8 @@ feature {NONE} -- Implementation
 			response.set_status_code (a_status_code)
 			response.header.put_content_type_text_html
 			response.header.put_content_length (s.count)
-			if
-				attached request.http_connection as l_connection and then
-				l_connection.is_case_insensitive_equal_general ("keep-alive")
-			then
-				response.header.put_header_key_value ("Connection", "keep-alive")
+			if request.is_keep_alive_http_connection then
+				response.header.put_connection_keep_alive
 			end
 			response.put_string (s)
 		end