add notification server, tests

ozon/notifications/enums.go

@@ -0,0 +1,19 @@
+package notifications
+
+type MessageType string
+
+const (
+	PingType                MessageType = "TYPE_PING"
+	NewPostingType          MessageType = "TYPE_NEW_POSTING"
+	PostingCancelledType    MessageType = "TYPE_POSTING_CANCELLED"
+	StateChangedType        MessageType = "TYPE_STATE_CHANGED"
+	CutoffDateChangedType   MessageType = "TYPE_CUTOFF_DATE_CHANGED"
+	DeliveryDateChangedType MessageType = "TYPE_DELIVERY_DATE_CHANGED"
+	CreateOrUpdateType      MessageType = "TYPE_CREATE_OR_UPDATE_ITEM"
+	PriceIndexChangedType   MessageType = "TYPE_PRICE_INDEX_CHANGED"
+	StocksChangedType       MessageType = "TYPE_STOCKS_CHANGED"
+	NewMessageType          MessageType = "TYPE_NEW_MESSAGE"
+	UpdateMessageType       MessageType = "TYPE_UPDATE_MESSAGE"
+	MessageReadType         MessageType = "TYPE_MESSAGE_READ"
+	ChatClosedType          MessageType = "TYPE_CHAT_CLOSED"
+)

ozon/notifications/server.go

@@ -1,21 +1,152 @@
 package notifications
 
 import (
+	"encoding/json"
+	"fmt"
+	"io/ioutil"
 	"net/http"
+	"time"
 )
 
-type NotificationServer struct{}
+type Handler func(req interface{}) error
 
-func NewNotificationServer() *NotificationServer {
+type NotificationServer struct {
-	return &NotificationServer{}
+	port     int
+	handlers map[MessageType]Handler
+}
+
+func NewNotificationServer(port int) *NotificationServer {
+	return &NotificationServer{
+		port:     port,
+		handlers: map[MessageType]Handler{},
+	}
 }
 
 func (ns *NotificationServer) Run() error {
 	mux := http.NewServeMux()
 	mux.HandleFunc("/", ns.handler)
-	return http.ListenAndServe("", mux)
+	server := http.Server{
+		Addr:    fmt.Sprintf("0.0.0.0:%d", ns.port),
+		Handler: mux,
+	}
+	return server.ListenAndServe()
 }
 
-func (ns *NotificationServer) handler(rw http.ResponseWriter, req *http.Request) {
+func (ns *NotificationServer) handler(rw http.ResponseWriter, httpReq *http.Request) {
+	mt := &Common{}
+	content, err := ioutil.ReadAll(httpReq.Body)
+	if err != nil {
+		ns.error(rw, http.StatusBadRequest, err)
+		return
+	}
+	if err := json.Unmarshal(content, mt); err != nil {
+		ns.error(rw, http.StatusBadRequest, err)
+		return
+	}
 
+	if mt.MessageType == PingType {
+		resp := pingResponse{
+			Version: "1.0",
+			Name:    "Ozon Seller API",
+			Time:    time.Now(),
+		}
+		respJson, err := json.Marshal(resp)
+		if err != nil {
+			ns.error(rw, http.StatusInternalServerError, err)
+			return
+		}
+
+		rw.WriteHeader(http.StatusOK)
+		rw.Write(respJson)
+		return
+	}
+
+	req, err := ns.unmarshal(mt.MessageType, content)
+	if err != nil {
+		ns.result(rw, false)
+		//ns.error(rw, http.StatusInternalServerError, err)
+		return
+	}
+	h, _ := ns.handlers[mt.MessageType]
+	if err := h(req); err != nil {
+		ns.result(rw, false)
+		//ns.error(rw, http.StatusInternalServerError, err)
+		return
+	}
+}
+
+func (ns *NotificationServer) Register(mt MessageType, handler func(req interface{}) error) {
+	ns.handlers[mt] = handler
+}
+
+func (ns *NotificationServer) unmarshal(messageType MessageType, content []byte) (interface{}, error) {
+	switch messageType {
+	case NewPostingType:
+		v := &NewPosting{}
+		err := json.Unmarshal(content, v)
+		return v, err
+	case PostingCancelledType:
+		v := &PostingCancelled{}
+		err := json.Unmarshal(content, v)
+		return v, err
+	case StateChangedType:
+		v := &StateChanged{}
+		err := json.Unmarshal(content, v)
+		return v, err
+	case CutoffDateChangedType:
+		v := &CutoffDateChanged{}
+		err := json.Unmarshal(content, v)
+		return v, err
+	case DeliveryDateChangedType:
+		v := &DeliveryDateChanged{}
+		err := json.Unmarshal(content, v)
+		return v, err
+	case CreateOrUpdateType:
+		v := &CreateOrUpdateItem{}
+		err := json.Unmarshal(content, v)
+		return v, err
+	case PriceIndexChangedType:
+		v := &PriceIndexChanged{}
+		err := json.Unmarshal(content, v)
+		return v, err
+	case StocksChangedType:
+		v := &StocksChanged{}
+		err := json.Unmarshal(content, v)
+		return v, err
+	case NewMessageType:
+		v := &NewMessage{}
+		err := json.Unmarshal(content, v)
+		return v, err
+	case UpdateMessageType:
+		v := &UpdateMessage{}
+		err := json.Unmarshal(content, v)
+		return v, err
+	case MessageReadType:
+		v := &MessageRead{}
+		err := json.Unmarshal(content, v)
+		return v, err
+	case ChatClosedType:
+		v := &ChatClosed{}
+		err := json.Unmarshal(content, v)
+		return v, err
+	default:
+		return nil, fmt.Errorf("unsupported type: %s", messageType)
+	}
+}
+
+func (ns *NotificationServer) error(rw http.ResponseWriter, statusCode int, err error) {
+	errResp := errorResponse{
+		Data: errorData{
+			Code:    fmt.Sprintf("%d", statusCode),
+			Message: err.Error(),
+		},
+	}
+	errJson, _ := json.Marshal(errResp)
+	rw.WriteHeader(statusCode)
+	rw.Write(errJson)
+}
+
+func (ns *NotificationServer) result(rw http.ResponseWriter, res bool) {
+	rw.WriteHeader(http.StatusOK)
+	rw.Write([]byte(fmt.Sprintf(`{"result": %t}`, res)))
 }

ozon/notifications/server_test.go

@@ -0,0 +1,118 @@
+package notifications
+
+import (
+	"encoding/json"
+	"fmt"
+	"io/ioutil"
+	"net/http"
+	"strings"
+	"testing"
+)
+
+const (
+	port = 5000
+)
+
+func TestNotificationServer(t *testing.T) {
+	testCases := []struct {
+		request  string
+		response string
+	}{
+		// PING
+		{
+			`{
+				"message_type": "string",
+				"time": "2019-08-24T14:15:22Z"
+			}`,
+			`{
+				"version": "1.0",
+				"name": "Ozon Seller API"
+			}`,
+		},
+		// REGISTERED HANDLER
+		{
+			`{  
+				"message_type": "TYPE_CHAT_CLOSED",
+				"chat_id": "b646d975-0c9c-4872-9f41-8b1e57181063",
+				"chat_type": "Buyer_Seller",
+				"user": {
+					"id": "115568",
+					"type": "Сustomer"
+				},
+				"seller_id": "7"
+			}`,
+			`{
+				"result": true
+			}`,
+		},
+		// UNREGISTERED HANDLER
+		{
+			`{  
+				"message_type": "TYPE_MESSAGE_READ",
+				"chat_id": "b646d975-0c9c-4872-9f41-8b1e57181063",
+				"chat_type": "Buyer_Seller",
+				"message_id": "3000000000817031942",
+				"created_at": "2022-07-18T20:58:04.528Z",    
+				"user": {
+					"id": "115568",
+					"type": "Сustomer"
+				},
+				"last_read_message_id": "3000000000817031942",
+				"seller_id": "7"
+			}`,
+			`{
+				"result": false
+			}`,
+		},
+	}
+
+	client := http.Client{}
+	server := NewNotificationServer(port)
+	server.Register(ChatClosedType, func(req interface{}) error {
+		_, ok := req.(*ChatClosed)
+		if !ok {
+			return fmt.Errorf("req is not of ChatClosed type")
+		}
+		return nil
+	})
+	go func() {
+		if err := server.Run(); err != nil {
+			t.Fatalf("notification server is down: %s", err)
+		}
+	}()
+
+	for _, testCase := range testCases {
+		httpResp, err := client.Post(fmt.Sprintf("http://127.0.0.1:%d/", port), "application/json", strings.NewReader(testCase.request))
+		if err != nil {
+			t.Error(err)
+			continue
+		}
+
+		gotJson, err := ioutil.ReadAll(httpResp.Body)
+		if err != nil {
+			t.Error(err)
+			continue
+		}
+
+		expected := map[string]string{}
+		got := map[string]string{}
+		json.Unmarshal(gotJson, got)
+		json.Unmarshal([]byte(testCase.response), expected)
+
+		if err := compare(expected, got); err != nil {
+			t.Error(err)
+			continue
+		}
+	}
+}
+
+func compare(expected map[string]string, got map[string]string) error {
+	for k, v := range expected {
+		if gotValue, ok := got[k]; !ok {
+			return fmt.Errorf("key %s is expected to present", k)
+		} else if gotValue != v {
+			return fmt.Errorf("key %s is not equal, got: %s, want: %s", k, gotValue, v)
+		}
+	}
+	return nil
+}

ozon/notifications/types.go

@@ -4,8 +4,7 @@ import "time"
 
 // Checking if the service is ready at initial connection and periodically after it
 type pingRequest struct {
-	// Notification type: TYPE_PING
+	Common
-	MessageType string `json:"message_type"`
 
 	// Date and time when the notification was sent in UTC format
 	Time time.Time `json:"time"`
@@ -22,10 +21,13 @@ type pingResponse struct {
 	Time time.Time `json:"time"`
 }
 
+type Common struct {
+	MessageType MessageType `json:"message_type"`
+}
+
 // New shipment
 type NewPosting struct {
-	// Notification type: TYPE_NEW_POSTING
+	Common
-	MessageType string `json:"message_type"`
 
 	// Shipment number
 	PostingNumber string `json:"posting_number"`
@@ -53,8 +55,7 @@ type Product struct {
 
 // Shipment cancellation
 type PostingCancelled struct {
-	// Notification type: TYPE_POSTING_CANCELLED
+	Common
-	MessageType string `json:"message_type"`
 
 	// Shipment number
 	PostingNumber string `json:"posting_number"`
@@ -91,8 +92,7 @@ type Reason struct {
 
 // Shipment status change
 type StateChanged struct {
-	// Notification type: TYPE_STATE_CHANGED
+	Common
-	MessageType string `json:"message_type"`
 
 	// Shipment number
 	PostingNumber string `json:"posting_number"`
@@ -112,8 +112,7 @@ type StateChanged struct {
 
 // Shipment shipping date change
 type CutoffDateChanged struct {
-	// Notification type: TYPE_CUTOFF_DATE_CHANGED
+	Common
-	MessageType string `json:"message_type"`
 
 	// Shipment number
 	PostingNumber string `json:"posting_number"`
@@ -133,8 +132,7 @@ type CutoffDateChanged struct {
 
 // Shipment delivery date change
 type DeliveryDateChanged struct {
-	// Notification type: TYPE_DELIVERY_DATE_CHANGED
+	Common
-	MessageType string `json:"message_type"`
 
 	// Shipment number
 	PostingNumber string `json:"posting_number"`
@@ -160,8 +158,7 @@ type DeliveryDateChanged struct {
 
 // Product creation and update or processing error
 type CreateOrUpdateItem struct {
-	// Notification type: TYPE_CREATE_OR_UPDATE_ITEM
+	Common
-	MessageType string `json:"message_type"`
 
 	// Product identifier in the seller's system
 	OfferId string `json:"offer_id"`
@@ -181,8 +178,7 @@ type CreateOrUpdateItem struct {
 
 // Product price index change
 type PriceIndexChanged struct {
-	// Notification type: TYPE_PRICE_INDEX_CHANGED
+	Common
-	MessageType string `json:"message_type"`
 
 	// Date and time of price index change
 	UpdatedAt time.Time `json:"updated_at"`
@@ -202,8 +198,7 @@ type PriceIndexChanged struct {
 
 // Stock change at the seller's warehouse
 type StocksChanged struct {
-	// Notification type: TYPE_STOCKS_CHANGED
+	Common
-	MessageType string `json:"message_type"`
 
 	// Array with products data
 	Items []Item `json:"items"`
@@ -239,8 +234,7 @@ type Stock struct {
 
 // New message in chat
 type NewMessage struct {
-	// Notification type: TYPE_NEW_MESSAGE
+	Common
-	MessageType string `json:"message_type"`
 
 	// Chat identifier
 	ChatId string `json:"chat_id"`
@@ -290,8 +284,7 @@ type MessageRead struct {
 
 // Chat is closed
 type ChatClosed struct {
-	// Notification type: TYPE_CHAT_CLOSED
+	Common
-	MessageType string `json:"message_type"`
 
 	// Chat identifier
 	ChatId string `json:"chat_id"`