Added framework for HTTP-conforming contracts

examples/restbucksCRUD/src/resource/order_handler.e

@@ -23,7 +23,7 @@ inherit
 
 	WSF_RESOURCE_HANDLER_HELPER
 		redefine
-			do_get,
+			do_get_head,
 			do_post,
 			do_put,
 			do_delete
@@ -53,27 +53,21 @@ feature -- API DOC
 
 feature -- HTTP Methods
 
-	do_get (req: WSF_REQUEST; res: WSF_RESPONSE)
-			-- Using GET to retrieve resource information.
-			-- If the GET request is SUCCESS, we response with
-			-- 200 OK, and a representation of the order
-			-- If the GET request is not SUCCESS, we response with
-			-- 404 Resource not found
-			-- If is a Condition GET and the resource does not change we send a
-			-- 304, Resource not modifed
+	do_get_head (a_req: WSF_REQUEST; a_res: WSF_RESPONSE; a_is_get: BOOLEAN)
+			-- <Precursor>
 		local
 			id:  STRING
 		do
-			if attached req.orig_path_info as orig_path then
+			if attached a_req.orig_path_info as orig_path then
 				id := get_order_id_from_path (orig_path)
 				if attached retrieve_order (id) as l_order then
-					if is_conditional_get (req, l_order) then
-						handle_resource_not_modified_response ("The resource" + orig_path + "does not change", req, res)
+					if is_conditional_get (a_req, l_order) then
+						handle_resource_not_modified_response ("The resource" + orig_path + "does not change", a_req, a_res)
 					else
-						compute_response_get (req, res, l_order)
+						compute_response_get_head (a_req, a_res, l_order, a_is_get)
 					end
 				else
-					handle_resource_not_found_response ("The following resource" + orig_path + " is not found ", req, res)
+					handle_resource_not_found_response ("The following resource" + orig_path + " is not found ", a_req, a_res)
 				end
 			end
 		end
@@ -93,7 +87,7 @@ feature -- HTTP Methods
 			end
 		end
 
-	compute_response_get (req: WSF_REQUEST; res: WSF_RESPONSE; l_order : ORDER)
+	compute_response_get_head (a_req: WSF_REQUEST; a_res: WSF_RESPONSE; l_order: ORDER; a_is_get: BOOLEAN)
 		local
 			h: HTTP_HEADER
 			l_msg : STRING
@@ -105,13 +99,15 @@ feature -- HTTP Methods
 			if attached {JSON_VALUE} json.value (l_order) as jv then
 				l_msg := jv.representation
 				h.put_content_length (l_msg.count)
-				if attached req.request_time as time then
+				if attached a_req.request_time as time then
 					h.add_header ("Date:" + time.formatted_out ("ddd,[0]dd mmm yyyy [0]hh:[0]mi:[0]ss.ff2") + " GMT")
 				end
 				h.add_header ("etag:" + etag_utils.md5_digest (l_order.out))
-				res.set_status_code ({HTTP_STATUS_CODE}.ok)
-				res.put_header_text (h.string)
-				res.put_string (l_msg)
+				a_res.set_status_code ({HTTP_STATUS_CODE}.ok)
+				a_res.put_header_text (h.string)
+				if a_is_get then
+					a_res.put_string (l_msg)
+				end
 			end
 		end
 

library/server/wsf/extension/wsf_method_handler.e

@@ -0,0 +1,24 @@
+note
+
+	description: "Conforming handler for any HTTP 1.1 standard method"
+
+	author: "Colin Adams"
+	date: "$Date$"
+	revision: "$Revision$"
+
+deferred class	WSF_METHOD_HANDLER
+
+feature -- Method
+
+	do_method (a_req: WSF_REQUEST; a_res: WSF_RESPONSE)
+			-- Respond to `a_req' using `a_res'.
+		require
+			a_req_not_void: a_req /= Void
+			a_res_not_void: a_res /= Void
+		deferred
+		ensure
+
+		end
+
+end
+

library/server/wsf/extension/wsf_method_handlers.e

@@ -0,0 +1,55 @@
+note
+
+	description: "Conforming handlers for HTTP 1.1 standard methods"
+
+	author: "Colin Adams"
+	date: "$Date$"
+	revision: "$Revision$"
+
+deferred class	WSF_METHOD_HANDLERS
+
+inherit
+
+	WSF_METHOD_HANDLER
+		rename
+			do_method as do_get
+		select
+			do_get
+		end
+
+	WSF_METHOD_HANDLER
+		rename
+			do_method as do_put
+		end
+
+	WSF_METHOD_HANDLER
+		rename
+			do_method as do_put
+		end
+
+	WSF_METHOD_HANDLER
+		rename
+			do_method as do_connect
+		end
+
+	WSF_METHOD_HANDLER
+		rename
+			do_method as do_head
+		end
+
+	WSF_METHOD_HANDLER
+		rename
+			do_method as do_options
+		end
+
+	WSF_METHOD_HANDLER
+		rename
+			do_method as do_trace
+		end
+
+feature -- Method
+
+	
+end
+
+	

library/server/wsf/extension/wsf_resource_handler_helper.e

@@ -4,13 +4,16 @@ note
 	date: "$Date$"
 	revision: "$Revision$"
 
-class
-	WSF_RESOURCE_HANDLER_HELPER
+class	WSF_RESOURCE_HANDLER_HELPER
+
+inherit
+
+	WSF_METHOD_HANDLERS
 
 feature -- Execute template
 
 	execute_methods (req: WSF_REQUEST; res: WSF_RESPONSE)
-			-- Execute request and dispatch according to the request method
+			-- Execute request and dispatch according to the request method.
 		local
 			m: READABLE_STRING_8
 		do
@@ -44,16 +47,31 @@ feature -- Method Get
 			do_get (req, res)
 		end
 
-	do_get (req: WSF_REQUEST; res: WSF_RESPONSE)
+	frozen do_get (req: WSF_REQUEST; res: WSF_RESPONSE)
 			-- Using GET to retrieve resource information.
-			-- If the GET request is SUCCESS, we response with
-			-- 200 OK, and a representation of the person
+			-- If the GET request is SUCCESS, we respond with
+			-- 200 OK, and a representation of the resource.
 			-- If the GET request is not SUCCESS, we response with
 			-- 404 Resource not found
 			-- If is a Condition GET and the resource does not change we send a
 			-- 304, Resource not modifed	
 		do
-			handle_not_implemented ("Method GET not implemented", req, res)
+			do_get_head (req, res, True)
+		end
+
+	do_get_head (a_req: WSF_REQUEST; a_res: WSF_RESPONSE; a_is_get: BOOLEAN)
+			-- Using GET or HEAD to retrieve resource information.
+			-- If the GET or HEAD request is SUCCESS, we respond with
+			-- 200 OK, and WITH/WITHOUT (for GET/HEAD respectively) a representation of the resource
+			-- If the GET or HEAD request is not SUCCESS, we respond with
+			-- 404 Resource not found.
+			-- If Conditional GET or HEAD and the resource does not change we send a
+			-- 304, Resource not modifed.
+		do
+			handle_not_implemented ("Methods GET and HEAD not implemented", a_req, a_res)
+		ensure
+			all_postconditions_for_do_get: a_is_get implies True
+			all_postconditions_for_do_head: not a_is_get implies True
 		end
 
 feature -- Method Post
@@ -139,16 +157,16 @@ feature -- Method HEAD
 			do_head (req, res)
 		end
 
-	do_head (req: WSF_REQUEST; res: WSF_RESPONSE)
+	frozen do_head (req: WSF_REQUEST; res: WSF_RESPONSE)
 			-- Using HEAD to retrieve resource information.
-			-- If the HEAD request is SUCCESS, we response with
-			-- 200 OK, and WITHOUT a representation of the person
-			-- If the HEAD request is not SUCCESS, we response with
-			-- 404 Resource not found
-			-- If is a Condition HEAD and the resource does not change we send a
-			-- 304, Resource not modifed	
+			-- If the HEAD request is SUCCESS, we respond with
+			-- 200 OK, and WITHOUT a representation of the resource.
+			-- If the HEAD request is not SUCCESS, we respond with
+			-- 404 Resource not found.
+			-- If Conditional HEAD and the resource does not change we send a
+			-- 304, Resource not modifed.
 		do
-			handle_not_implemented ("Method HEAD not implemented", req, res)
+			do_get_head (req, res, False)
 		end
 
 feature -- Method OPTIONS
@@ -172,6 +190,7 @@ feature -- Method TRACE
 
 	do_trace (req: WSF_REQUEST; res: WSF_RESPONSE)
 		do
+			-- TODO - implement frozen, as there is only one permitted semantic.
 			handle_not_implemented ("Method TRACE not implemented", req, res)
 		end