Updated, improved and cleaned RESTbucks example.

Moved it under "rest" subfolder.

examples/rest/restbucks_CRUD/src/database/restbucks_api.e

@@ -0,0 +1,173 @@
+note
+	description: "Summary description for {RESTBUCKS_API}."
+	date: "$Date$"
+	revision: "$Revision$"
+
+class
+	RESTBUCKS_API
+
+create
+	make
+
+feature {NONE} -- Initialization
+
+	make
+		local
+			db: BASIC_JSON_FS_DATABASE
+		do
+			create db.make (database_path)
+			db.serialization.register (create {ORDER_JSON_SERIALIZATION}, {ORDER})
+			database := db
+		end
+
+feature -- Access
+
+	orders_count: INTEGER
+			-- Number of existing orders.
+		do
+			Result := database.count_of ({ORDER})
+		end
+
+	has_order (a_id: READABLE_STRING_GENERAL): BOOLEAN
+		do
+			Result := database.has ({ORDER}, a_id)
+		end
+
+	order (a_id: READABLE_STRING_GENERAL): detachable ORDER
+		do
+			if attached {ORDER} database.item ({ORDER}, a_id) as o then
+				Result := o
+			end
+		end
+
+feature -- Element change
+
+	submit_order (a_order: ORDER)
+			-- Submit new order `a_order`.
+		require
+			no_id: not a_order.has_id
+		do
+			a_order.mark_submitted
+			save_order (a_order)
+		end
+
+	save_order (a_order: ORDER)
+		local
+			cl: CELL [detachable READABLE_STRING_GENERAL]
+		do
+			a_order.add_revision
+			if a_order.has_id then
+				create cl.put (a_order.id)
+			else
+				create cl.put (Void)
+			end
+			database.save ({ORDER}, a_order, cl)
+			if attached cl.item as l_new_id then
+				if l_new_id.is_valid_as_string_8 then
+					a_order.set_id (l_new_id.to_string_8)
+				else
+					check valid_id: False end
+				end
+			end
+		ensure
+			has_id: a_order.has_id
+			incremented_revision: a_order.revision > old (a_order.revision)
+		end
+
+	delete_order (a_order: ORDER)
+		do
+			database.delete ({ORDER}, a_order.id)
+		end
+
+feature -- Access: order status
+
+	is_valid_status_state (a_status: STRING): BOOLEAN
+			-- Is `a_status' a valid order state
+		do
+			Result := Order_states.has (a_status.as_lower)
+		end
+
+	Order_states : ARRAY [STRING]
+			-- List of valid status states
+		once
+			Result := <<
+							status_unset,
+							status_submitted,
+							status_pay, 	status_payed,
+							status_cancel, 	status_canceled,
+							status_prepare,	status_prepared,
+							status_deliver,
+							status_completed
+						>>
+			Result.compare_objects
+		end
+
+	is_valid_transition (a_order: ORDER; a_new_status: STRING): BOOLEAN
+			-- Is transition from `a_order.status` to `a_new_status` valid for `a_order`?
+		local
+			l_order_status: READABLE_STRING_GENERAL
+			l_new_status: STRING
+		do
+			l_order_status := a_order.status
+			l_new_status := a_new_status.as_lower
+			if l_order_status.same_string (l_new_status) then
+					-- Same status is valid, if it is a valid status
+				Result := is_valid_status_state (l_new_status)
+			else
+				if l_order_status.same_string (status_submitted) then
+					Result := 	l_new_status.same_string (status_pay)
+							or 	l_new_status.same_string (status_cancel)
+				elseif l_order_status.same_string (status_pay) then
+					Result := 	l_new_status.same_string (status_payed)
+				elseif l_order_status.same_string (status_cancel) then
+					Result := 	l_new_status.same_string (status_canceled)
+				elseif l_order_status.same_string (status_payed) then
+					Result := l_new_status.same_string (status_prepared)
+				elseif l_order_status.same_string (status_prepared) then
+					Result := l_new_status.same_string (status_deliver)
+				elseif l_order_status.same_string (status_deliver) then
+					Result := l_new_status.same_string (status_completed)
+				end
+			end
+		end
+
+	is_state_valid_to_update (a_status : STRING) : BOOLEAN
+			-- Is it possible to update order with status `a_status`?
+		do
+			if
+				a_status.same_string (status_submitted)
+				or else  a_status.same_string (status_pay)
+				or else  a_status.same_string (status_payed)
+			then
+				Result := True
+			end
+		end
+
+feature -- Constants: order status
+
+	status_unset: STRING = "unset"
+	status_submitted: STRING = "submitted"
+	status_pay: STRING = "pay"
+	status_payed: STRING = "payed"
+	status_cancel: STRING = "cancel"
+	status_canceled: STRING = "canceled"
+	status_prepare: STRING = "prepare"
+	status_prepared: STRING = "prepared"
+	status_deliver: STRING = "deliver"
+	status_completed: STRING = "completed"
+
+feature {NONE} -- Access
+
+	database: BASIC_DATABASE
+
+feature {NONE} -- Implementation
+
+	database_path: PATH
+		once
+			create Result.make_from_string ("db")
+		end
+
+;note
+	copyright: "2011-2017, Javier Velilla and others"
+	license: "Eiffel Forum License v2 (see http://www.eiffel.com/licensing/forum.txt)"
+end