Reduce cognitive complexity and replace duplicated literals with constants across modules

consumer/nf_management.go

@@ -20,6 +20,8 @@ import (
 	"github.com/omec-project/udm/logger"
 )
 
+const errServerNoResponse = "server no response"
+
 func BuildNFInstance(udmContext *udmContext.UDMContext) (profile models.NfProfile, err error) {
 	profile.NfInstanceId = udmContext.NfId
 	profile.NfStatus = models.NfStatus_REGISTERED
@@ -116,7 +118,7 @@ func SendDeregisterNFInstance() (problemDetails *models.ProblemDetails, err erro
 		problem := err.(openapi.GenericOpenAPIError).Model().(models.ProblemDetails)
 		problemDetails = &problem
 	} else {
-		err = openapi.ReportError("server no response")
+		err = openapi.ReportError(errServerNoResponse)
 	}
 	return
 }
@@ -146,7 +148,7 @@ var SendUpdateNFInstance = func(patchItem []models.PatchItem) (nfProfile models.
 		problem := err.(openapi.GenericOpenAPIError).Model().(models.ProblemDetails)
 		problemDetails = &problem
 	} else {
-		err = openapi.ReportError("server no response")
+		err = openapi.ReportError(errServerNoResponse)
 	}
 	return
 }
@@ -176,7 +178,7 @@ func SendCreateSubscription(nrfUri string, nrfSubscriptionData models.NrfSubscri
 		problem := err.(openapi.GenericOpenAPIError).Model().(models.ProblemDetails)
 		problemDetails = &problem
 	} else {
-		err = openapi.ReportError("server no response")
+		err = openapi.ReportError(errServerNoResponse)
 	}
 	return
 }
@@ -206,7 +208,7 @@ func SendRemoveSubscription(subscriptionId string) (problemDetails *models.Probl
 		problem := err.(openapi.GenericOpenAPIError).Model().(models.ProblemDetails)
 		problemDetails = &problem
 	} else {
-		err = openapi.ReportError("server no response")
+		err = openapi.ReportError(errServerNoResponse)
 	}
 	return
 }

context/context.go

@@ -33,6 +33,8 @@ const (
 	LocationUriAuthEvents // New constant for AuthEvent resource URI type.
 )
 
+const uecmUriPrefix = "/nudm-uecm/v1/"
+
 func init() {
 	UDM_Self().NfService = make(map[models.ServiceName]models.NfService)
 	UDM_Self().EeSubscriptionIDGenerator = idgenerator.NewGenerator(1, math.MaxInt32)
@@ -357,11 +359,11 @@ func (context *UDMContext) GetAmfNon3gppRegContext(supi string) *models.AmfNon3G
 func (ue *UdmUeContext) GetLocationURI(types int) string {
 	switch types {
 	case LocationUriAmf3GppAccessRegistration:
-		return UDM_Self().GetIPv4Uri() + "/nudm-uecm/v1/" + ue.Supi + "/registrations/amf-3gpp-access"
+		return UDM_Self().GetIPv4Uri() + uecmUriPrefix + ue.Supi + "/registrations/amf-3gpp-access"
 	case LocationUriAmfNon3GppAccessRegistration:
-		return UDM_Self().GetIPv4Uri() + "/nudm-uecm/v1/" + ue.Supi + "/registrations/amf-non-3gpp-access"
+		return UDM_Self().GetIPv4Uri() + uecmUriPrefix + ue.Supi + "/registrations/amf-non-3gpp-access"
 	case LocationUriSmfRegistration:
-		return UDM_Self().GetIPv4Uri() + "/nudm-uecm/v1/" + ue.Supi + "/registrations/smf-registrations/" + ue.PduSessionID
+		return UDM_Self().GetIPv4Uri() + uecmUriPrefix + ue.Supi + "/registrations/smf-registrations/" + ue.PduSessionID
 	}
 	return ""
 }

eventexposure/api_create_ee_subscription.go

@@ -25,6 +25,8 @@ import (
 	"github.com/omec-project/util/httpwrapper"
 )
 
+const contentTypeJson = "application/json"
+
 // HTTPCreateEeSubscription - Subscribe
 func HTTPCreateEeSubscription(c *gin.Context) {
 	var eeSubscriptionReq models.EeSubscription
@@ -42,7 +44,7 @@ func HTTPCreateEeSubscription(c *gin.Context) {
 		return
 	}
 
-	err = openapi.Deserialize(&eeSubscriptionReq, requestBody, "application/json")
+	err = openapi.Deserialize(&eeSubscriptionReq, requestBody, contentTypeJson)
 	if err != nil {
 		problemDetail := "[Request Body] " + err.Error()
 		rsp := models.ProblemDetails{
@@ -60,7 +62,7 @@ func HTTPCreateEeSubscription(c *gin.Context) {
 
 	rsp := producer.HandleCreateEeSubscription(req)
 
-	responseBody, err := openapi.Serialize(rsp.Body, "application/json")
+	responseBody, err := openapi.Serialize(rsp.Body, contentTypeJson)
 	if err != nil {
 		logger.EeLog.Errorln(err)
 		problemDetails := models.ProblemDetails{
@@ -70,6 +72,6 @@ func HTTPCreateEeSubscription(c *gin.Context) {
 		}
 		c.JSON(http.StatusInternalServerError, problemDetails)
 	} else {
-		c.Data(rsp.Status, "application/json", responseBody)
+		c.Data(rsp.Status, contentTypeJson, responseBody)
 	}
 }

eventexposure/api_update_ee_subscription.go

@@ -42,7 +42,7 @@ func HTTPUpdateEeSubscription(c *gin.Context) {
 		return
 	}
 
-	err = openapi.Deserialize(&patchList, requestBody, "application/json")
+	err = openapi.Deserialize(&patchList, requestBody, contentTypeJson)
 	if err != nil {
 		problemDetail := "[Request Body] " + err.Error()
 		rsp := models.ProblemDetails{
@@ -64,7 +64,7 @@ func HTTPUpdateEeSubscription(c *gin.Context) {
 	if rsp.Status == http.StatusNoContent {
 		c.Status(rsp.Status)
 	} else {
-		responseBody, err := openapi.Serialize(rsp.Body, "application/json")
+		responseBody, err := openapi.Serialize(rsp.Body, contentTypeJson)
 		if err != nil {
 			logger.EeLog.Errorln(err)
 			problemDetails := models.ProblemDetails{
@@ -74,7 +74,7 @@ func HTTPUpdateEeSubscription(c *gin.Context) {
 			}
 			c.JSON(http.StatusInternalServerError, problemDetails)
 		} else {
-			c.Data(rsp.Status, "application/json", responseBody)
+			c.Data(rsp.Status, contentTypeJson, responseBody)
 		}
 	}
 }

httpcallback/data_change_notification_to_nf.go

@@ -16,6 +16,8 @@ import (
 	"github.com/omec-project/util/httpwrapper"
 )
 
+const contentTypeJson = "application/json"
+
 func HTTPDataChangeNotificationToNF(c *gin.Context) {
 	var dataChangeNotify models.DataChangeNotify
 	// step 1: retrieve http request body
@@ -33,7 +35,7 @@ func HTTPDataChangeNotificationToNF(c *gin.Context) {
 	}
 
 	// step 2: convert requestBody to openapi models
-	err = openapi.Deserialize(&dataChangeNotify, requestBody, "application/json")
+	err = openapi.Deserialize(&dataChangeNotify, requestBody, contentTypeJson)
 	if err != nil {
 		problemDetail := "[Request Body] " + err.Error()
 		rsp := models.ProblemDetails{
@@ -50,7 +52,7 @@ func HTTPDataChangeNotificationToNF(c *gin.Context) {
 	req.Params["supi"] = c.Params.ByName("supi")
 
 	rsp := producer.HandleDataChangeNotificationToNFRequest(req)
-	responseBody, err := openapi.Serialize(rsp.Body, "application/json")
+	responseBody, err := openapi.Serialize(rsp.Body, contentTypeJson)
 	if err != nil {
 		logger.CallbackLog.Errorln(err)
 		problemDetails := models.ProblemDetails{
@@ -60,6 +62,6 @@ func HTTPDataChangeNotificationToNF(c *gin.Context) {
 		}
 		c.JSON(http.StatusInternalServerError, problemDetails)
 	} else {
-		c.Data(rsp.Status, "application/json", responseBody)
+		c.Data(rsp.Status, contentTypeJson, responseBody)
 	}
 }

parameterprovision/api_subscription_data_update.go

@@ -25,6 +25,8 @@ import (
 	"github.com/omec-project/util/httpwrapper"
 )
 
+const contentTypeJson = "application/json"
+
 // Update - provision parameters
 func HTTPUpdate(c *gin.Context) {
 	var ppDataReq models.PpData
@@ -44,7 +46,7 @@ func HTTPUpdate(c *gin.Context) {
 	}
 
 	// step 2: convert requestBody to openapi models
-	err = openapi.Deserialize(&ppDataReq, requestBody, "application/json")
+	err = openapi.Deserialize(&ppDataReq, requestBody, contentTypeJson)
 	if err != nil {
 		problemDetail := "[Request Body] " + err.Error()
 		rsp := models.ProblemDetails{
@@ -62,7 +64,7 @@ func HTTPUpdate(c *gin.Context) {
 
 	rsp := producer.HandleUpdateRequest(req)
 
-	responseBody, err := openapi.Serialize(rsp.Body, "application/json")
+	responseBody, err := openapi.Serialize(rsp.Body, contentTypeJson)
 	if err != nil {
 		logger.PpLog.Errorln(err)
 		problemDetails := models.ProblemDetails{
@@ -72,6 +74,6 @@ func HTTPUpdate(c *gin.Context) {
 		}
 		c.JSON(http.StatusInternalServerError, problemDetails)
 	} else {
-		c.Data(rsp.Status, "application/json", responseBody)
+		c.Data(rsp.Status, contentTypeJson, responseBody)
 	}
 }

producer/event_exposure.go

@@ -16,7 +16,13 @@ import (
 	"github.com/omec-project/util/httpwrapper"
 )
 
-const anyUE = "anyUE"
+const (
+	anyUE            = "anyUE"
+	prefixMsisdn     = "msisdn-"
+	prefixExtid      = "extid-"
+	prefixExtgroupId = "extgroupid-"
+	fmtPatchItem     = "patch item: %+v"
+)
 
 func HandleCreateEeSubscription(request *httpwrapper.Request) *httpwrapper.Response {
 	logger.EeLog.Infoln("Handle Create EE Subscription")
@@ -47,10 +53,10 @@ func CreateEeSubscriptionProcedure(ueIdentity string,
 	logger.EeLog.Debugf("udIdentity: %s", ueIdentity)
 	switch {
 	// GPSI (MSISDN identifier) represents a single UE
-	case strings.HasPrefix(ueIdentity, "msisdn-"):
+	case strings.HasPrefix(ueIdentity, prefixMsisdn):
 		fallthrough
 	// GPSI (External identifier) represents a single UE
-	case strings.HasPrefix(ueIdentity, "extid-"):
+	case strings.HasPrefix(ueIdentity, prefixExtid):
 		if ue, ok := udmSelf.UdmUeFindByGpsi(ueIdentity); ok {
 			id, err := udmSelf.EeSubscriptionIDGenerator.Allocate()
 			if err != nil {
@@ -75,7 +81,7 @@ func CreateEeSubscriptionProcedure(ueIdentity string,
 			return nil, problemDetails
 		}
 	// external groupID represents a group of UEs
-	case strings.HasPrefix(ueIdentity, "extgroupid-"):
+	case strings.HasPrefix(ueIdentity, prefixExtgroupId):
 		id, err := udmSelf.EeSubscriptionIDGenerator.Allocate()
 		if err != nil {
 			problemDetails := &models.ProblemDetails{
@@ -145,13 +151,13 @@ func DeleteEeSubscriptionProcedure(ueIdentity string, subscriptionID string) {
 	udmSelf := udm_context.UDM_Self()
 
 	switch {
-	case strings.HasPrefix(ueIdentity, "msisdn-"):
+	case strings.HasPrefix(ueIdentity, prefixMsisdn):
 		fallthrough
-	case strings.HasPrefix(ueIdentity, "extid-"):
+	case strings.HasPrefix(ueIdentity, prefixExtid):
 		if ue, ok := udmSelf.UdmUeFindByGpsi(ueIdentity); ok {
 			delete(ue.EeSubscriptions, subscriptionID)
 		}
-	case strings.HasPrefix(ueIdentity, "extgroupid-"):
+	case strings.HasPrefix(ueIdentity, prefixExtgroupId):
 		udmSelf.UdmUePool.Range(func(key, value interface{}) bool {
 			ue := value.(*udm_context.UdmUeContext)
 			if ue.ExternalGroupID == ueIdentity {
@@ -190,73 +196,58 @@ func HandleUpdateEeSubscription(request *httpwrapper.Request) *httpwrapper.Respo
 }
 
 // TODO: complete this procedure based on TS 29503 5.5
+// applyPatchToUe localizes the patching logic and reduces nesting in the main caller.
+func applyPatchToUe(ue *udm_context.UdmUeContext, subscriptionID string, patchList []models.PatchItem) bool {
+	if _, ok := ue.EeSubscriptions[subscriptionID]; !ok {
+		return false
+	}
+	for _, patchItem := range patchList {
+		logger.EeLog.Debugf(fmtPatchItem, patchItem)
+		// TODO: patch the Eesubscription
+	}
+	return true
+}
+
 func UpdateEeSubscriptionProcedure(ueIdentity string, subscriptionID string,
 	patchList []models.PatchItem,
 ) *models.ProblemDetails {
 	udmSelf := udm_context.UDM_Self()
 
 	switch {
-	case strings.HasPrefix(ueIdentity, "msisdn-"):
-		fallthrough
-	case strings.HasPrefix(ueIdentity, "extid-"):
-		if ue, ok := udmSelf.UdmUeFindByGpsi(ueIdentity); ok {
-			if _, ok := ue.EeSubscriptions[subscriptionID]; ok {
-				for _, patchItem := range patchList {
-					logger.EeLog.Debugf("patch item: %+v", patchItem)
-					// TODO: patch the Eesubscription
-				}
-				return nil
-			} else {
-				problemDetails := &models.ProblemDetails{
-					Status: http.StatusNotFound,
-					Cause:  "SUBSCRIPTION_NOT_FOUND",
-				}
-				return problemDetails
-			}
-		} else {
-			problemDetails := &models.ProblemDetails{
+	case strings.HasPrefix(ueIdentity, prefixMsisdn), strings.HasPrefix(ueIdentity, prefixExtid):
+		ue, ok := udmSelf.UdmUeFindByGpsi(ueIdentity)
+		if !ok || !applyPatchToUe(ue, subscriptionID, patchList) {
+			return &models.ProblemDetails{
 				Status: http.StatusNotFound,
 				Cause:  "SUBSCRIPTION_NOT_FOUND",
 			}
-			return problemDetails
 		}
-	case strings.HasPrefix(ueIdentity, "extgroupid-"):
+		return nil
+
+	case strings.HasPrefix(ueIdentity, prefixExtgroupId):
 		udmSelf.UdmUePool.Range(func(key, value interface{}) bool {
 			ue := value.(*udm_context.UdmUeContext)
 			if ue.ExternalGroupID == ueIdentity {
-				if _, ok := ue.EeSubscriptions[subscriptionID]; ok {
-					for _, patchItem := range patchList {
-						logger.EeLog.Debugf("patch item: %+v", patchItem)
-						// TODO: patch the Eesubscription
-					}
-				}
+				applyPatchToUe(ue, subscriptionID, patchList)
 			}
 			return true
 		})
 		return nil
+
 	case ueIdentity == anyUE:
 		udmSelf.UdmUePool.Range(func(key, value interface{}) bool {
-			ue := value.(*udm_context.UdmUeContext)
-			if _, ok := ue.EeSubscriptions[subscriptionID]; ok {
-				for _, patchItem := range patchList {
-					logger.EeLog.Debugf("patch item: %+v", patchItem)
-					// TODO: patch the Eesubscription
-				}
-			}
+			applyPatchToUe(value.(*udm_context.UdmUeContext), subscriptionID, patchList)
 			return true
 		})
 		return nil
+
 	default:
-		problemDetails := &models.ProblemDetails{
+		return &models.ProblemDetails{
 			Status: http.StatusBadRequest,
 			Cause:  "MANDATORY_IE_INCORRECT",
 			InvalidParams: []models.InvalidParam{
-				{
-					Param:  "ueIdentity",
-					Reason: "incorrect format",
-				},
+				{Param: "ueIdentity", Reason: "incorrect format"},
 			},
 		}
-		return problemDetails
 	}
 }