From 6664805c748b0f47ee20309c0d50266a3dfa55b0 Mon Sep 17 00:00:00 2001
From: akhila-s06 <94685258+akhila-s06@users.noreply.github.com>
Date: Fri, 19 Apr 2024 09:15:58 +0530
Subject: [PATCH] paging fix,handle deregistration notification implimentation
 (#214)

Co-authored-by: gab-arrobo <gabriel.arrobo@intel.com>
---
 context/amf_ran.go               |  1 -
 httpcallback/api_dereg_notify.go | 68 ++++++++++++++++++++++++++++++++
 httpcallback/router.go           |  6 +++
 producer/callback.go             | 49 +++++++++++++++++++++++
 4 files changed, 123 insertions(+), 1 deletion(-)
 create mode 100644 httpcallback/api_dereg_notify.go

diff --git a/context/amf_ran.go b/context/amf_ran.go
index bfae9e18..d52f10d3 100644
--- a/context/amf_ran.go
+++ b/context/amf_ran.go
@@ -161,7 +161,6 @@ func (ran *AmfRan) SetRanId(ranNodeId *ngapType.GlobalRANNodeID) {
 	if ranId.GNbId != nil {
 		ran.GnbId += ranId.GNbId.GNBValue
 	}
-	AMF_Self().AmfRanPool.Store(ran.GnbId, ran)
 }
 
 func (ran *AmfRan) ConvertGnbIdToRanId(gnbId string) (ranNodeId *models.GlobalRanNodeId) {
diff --git a/httpcallback/api_dereg_notify.go b/httpcallback/api_dereg_notify.go
new file mode 100644
index 00000000..accc2d7e
--- /dev/null
+++ b/httpcallback/api_dereg_notify.go
@@ -0,0 +1,68 @@
+// SPDX-FileCopyrightText: 2022 Infosys Limited
+// Copyright 2019 free5GC.org
+//
+// SPDX-License-Identifier: Apache-2.0
+//
+
+package httpcallback
+
+import (
+	"net/http"
+
+	"github.com/gin-gonic/gin"
+	"github.com/omec-project/amf/logger"
+	"github.com/omec-project/amf/producer"
+	"github.com/omec-project/openapi"
+	"github.com/omec-project/openapi/models"
+	"github.com/omec-project/util/httpwrapper"
+)
+
+func HTTPDeregistrationNotification(c *gin.Context) {
+	var deregistrationData models.DeregistrationData
+
+	requestBody, err := c.GetRawData()
+	if err != nil {
+		logger.CallbackLog.Errorf("Get Request Body error: %+v", err)
+		problemDetail := models.ProblemDetails{
+			Title:  "System failure",
+			Status: http.StatusInternalServerError,
+			Detail: err.Error(),
+			Cause:  "SYSTEM_FAILURE",
+		}
+		c.JSON(http.StatusInternalServerError, problemDetail)
+		return
+	}
+
+	err = openapi.Deserialize(&deregistrationData, requestBody, "application/json")
+	if err != nil {
+		problemDetail := "[Request Body] " + err.Error()
+		rsp := models.ProblemDetails{
+			Title:  "Malformed request syntax",
+			Status: http.StatusBadRequest,
+			Detail: problemDetail,
+		}
+		logger.CallbackLog.Errorln(problemDetail)
+		c.JSON(http.StatusBadRequest, rsp)
+		return
+	}
+
+	req := httpwrapper.NewRequest(c.Request, deregistrationData)
+	if supi, exists := c.Params.Get("supi"); exists {
+		req.Params["supi"] = supi
+	}
+	rsp := producer.HandleDeregistrationNotification(req)
+
+	responseBody, err := openapi.Serialize(rsp.Body, "application/json")
+	if err != nil {
+		logger.CallbackLog.Errorln(err)
+		problemDetails := models.ProblemDetails{
+			Status: http.StatusInternalServerError,
+			Cause:  "SYSTEM_FAILURE",
+			Detail: err.Error(),
+		}
+		c.JSON(http.StatusInternalServerError, problemDetails)
+	} else {
+		c.Data(rsp.Status, "application/json", responseBody)
+	}
+
+}
diff --git a/httpcallback/router.go b/httpcallback/router.go
index 2b26dd07..5fd82595 100644
--- a/httpcallback/router.go
+++ b/httpcallback/router.go
@@ -109,4 +109,10 @@ var routes = Routes{
 		"/nf-status-notify",
 		HTTPNfSubscriptionStatusNotify,
 	},
+	{
+		"DeregistrationNotify",
+		strings.ToUpper("Post"),
+		":supi/deregistration-notify",
+		HTTPDeregistrationNotification,
+	},
 }
diff --git a/producer/callback.go b/producer/callback.go
index 414e4470..639c1f70 100644
--- a/producer/callback.go
+++ b/producer/callback.go
@@ -493,3 +493,52 @@ func NfSubscriptionStatusNotifyProcedure(notificationData models.NotificationDat
 
 	return nil
 }
+
+func HandleDeregistrationNotification(request *httpwrapper.Request) *httpwrapper.Response {
+	logger.ProducerLog.Infoln("Handle Deregistration Notification")
+	deregistrationData := request.Body.(models.DeregistrationData)
+
+	switch deregistrationData.DeregReason {
+	case "SUBSCRIPTION_WITHDRAWN":
+		amfSelf := context.AMF_Self()
+		if supi, exists := request.Params["supi"]; exists {
+			reqUri := request.URL.RequestURI()
+			if ue, ok := amfSelf.AmfUeFindBySupi(supi); ok {
+				logger.ProducerLog.Debugln("amf ue found: ", ue.Supi)
+				sbiMsg := context.SbiMsg{
+					UeContextId: ue.Supi,
+					ReqUri:      reqUri,
+					Msg:         nil,
+					Result:      make(chan context.SbiResponseMsg, 10),
+				}
+				ue.EventChannel.UpdateSbiHandler(HandleOAMPurgeUEContextRequest)
+				ue.EventChannel.SubmitMessage(sbiMsg)
+				msg := <-sbiMsg.Result
+				if msg.ProblemDetails != nil {
+					return httpwrapper.NewResponse(int(msg.ProblemDetails.(*models.ProblemDetails).Status), nil, msg.ProblemDetails.(*models.ProblemDetails))
+				} else {
+					return httpwrapper.NewResponse(http.StatusNoContent, nil, nil)
+				}
+			} else {
+				return httpwrapper.NewResponse(http.StatusNotFound, nil, nil)
+			}
+		}
+
+	case "":
+		problemDetails := &models.ProblemDetails{
+			Status: http.StatusBadRequest,
+			Cause:  "MANDATORY_IE_MISSING", // Defined in TS 29.503 6.2.5.2
+			Detail: "Missing IE [DeregReason] in DeregistrationData",
+		}
+		return httpwrapper.NewResponse(int(problemDetails.Status), nil, problemDetails)
+
+	default:
+		problemDetails := &models.ProblemDetails{
+			Status: http.StatusNotImplemented,
+			Cause:  "NOT_IMPLEMENTED", // Defined in TS 29.503
+			Detail: "Unsupported [DeregReason] in DeregistrationData",
+		}
+		return httpwrapper.NewResponse(int(problemDetails.Status), nil, problemDetails)
+	}
+	return nil
+}