Linking events and statistics

api/api.md

@@ -35,6 +35,7 @@
 
 - [lorawan-stack/api/applicationserver.proto](#lorawan-stack/api/applicationserver.proto)
     - [ApplicationLink](#ttn.lorawan.v3.ApplicationLink)
+    - [ApplicationLinkStats](#ttn.lorawan.v3.ApplicationLinkStats)
     - [GetApplicationLinkRequest](#ttn.lorawan.v3.GetApplicationLinkRequest)
     - [SetApplicationLinkRequest](#ttn.lorawan.v3.SetApplicationLinkRequest)
 
@@ -797,6 +798,26 @@ where the user or organization is collaborator on.
 
 
 
+<a name="ttn.lorawan.v3.ApplicationLinkStats"/>
+
+### ApplicationLinkStats
+Link stats as monitored by the Application Server.
+
+
+| Field | Type | Label | Description |
+| ----- | ---- | ----- | ----------- |
+| linked_at | [google.protobuf.Timestamp](#google.protobuf.Timestamp) |  |  |
+| network_server_address | [string](#string) |  |  |
+| last_up_received_at | [google.protobuf.Timestamp](#google.protobuf.Timestamp) |  | Timestamp when the last upstream message has been received from a Network Server. This can be a join-accept, uplink message or downlink message event. |
+| up_count | [uint64](#uint64) |  | Number of upstream messages received. |
+| last_downlink_forwarded_at | [google.protobuf.Timestamp](#google.protobuf.Timestamp) |  | Timestamp when the last downlink message has been forwarded to a Network Server. |
+| downlink_count | [uint64](#uint64) |  | Number of downlink messages forwarded. |
+
+
+
+
+
+
 <a name="ttn.lorawan.v3.GetApplicationLinkRequest"/>
 
 ### GetApplicationLinkRequest
@@ -859,6 +880,7 @@ The As service manages the Application Server.
 | GetLink | [GetApplicationLinkRequest](#ttn.lorawan.v3.GetApplicationLinkRequest) | [ApplicationLink](#ttn.lorawan.v3.GetApplicationLinkRequest) |  |
 | SetLink | [SetApplicationLinkRequest](#ttn.lorawan.v3.SetApplicationLinkRequest) | [ApplicationLink](#ttn.lorawan.v3.SetApplicationLinkRequest) |  |
 | DeleteLink | [ApplicationIdentifiers](#ttn.lorawan.v3.ApplicationIdentifiers) | [.google.protobuf.Empty](#ttn.lorawan.v3.ApplicationIdentifiers) |  |
+| GetLinkStats | [ApplicationIdentifiers](#ttn.lorawan.v3.ApplicationIdentifiers) | [ApplicationLinkStats](#ttn.lorawan.v3.ApplicationIdentifiers) |  |
 
 
 <a name="ttn.lorawan.v3.AsEndDeviceRegistry"/>

api/api.swagger.json

@@ -864,6 +864,30 @@
         ]
       }
     },
+    "/as/applications/{application_id}/link/stats": {
+      "get": {
+        "operationId": "GetLinkStats",
+        "responses": {
+          "200": {
+            "description": "A successful response.",
+            "schema": {
+              "$ref": "#/definitions/v3ApplicationLinkStats"
+            }
+          }
+        },
+        "parameters": [
+          {
+            "name": "application_id",
+            "in": "path",
+            "required": true,
+            "type": "string"
+          }
+        ],
+        "tags": [
+          "As"
+        ]
+      }
+    },
     "/as/applications/{device.ids.application_ids.application_id}/devices": {
       "post": {
         "operationId": "Set2",
@@ -1859,6 +1883,38 @@
         ]
       }
     },
+    "/gs/gateways/{gateway_id}/connection/stats": {
+      "get": {
+        "operationId": "GetGatewayConnectionStats",
+        "responses": {
+          "200": {
+            "description": "A successful response.",
+            "schema": {
+              "$ref": "#/definitions/v3GatewayConnectionStats"
+            }
+          }
+        },
+        "parameters": [
+          {
+            "name": "gateway_id",
+            "in": "path",
+            "required": true,
+            "type": "string"
+          },
+          {
+            "name": "eui",
+            "description": "Secondary identifier, which can only be used in specific requests.",
+            "in": "query",
+            "required": false,
+            "type": "string",
+            "format": "byte"
+          }
+        ],
+        "tags": [
+          "Gs"
+        ]
+      }
+    },
     "/invitations": {
       "get": {
         "operationId": "List",
@@ -5346,6 +5402,39 @@
         }
       }
     },
+    "v3ApplicationLinkStats": {
+      "type": "object",
+      "properties": {
+        "linked_at": {
+          "type": "string",
+          "format": "date-time"
+        },
+        "network_server_address": {
+          "type": "string"
+        },
+        "last_up_received_at": {
+          "type": "string",
+          "format": "date-time",
+          "description": "Timestamp when the last upstream message has been received from a Network Server.\nThis can be a join-accept, uplink message or downlink message event."
+        },
+        "up_count": {
+          "type": "string",
+          "format": "uint64",
+          "description": "Number of upstream messages received."
+        },
+        "last_downlink_forwarded_at": {
+          "type": "string",
+          "format": "date-time",
+          "description": "Timestamp when the last downlink message has been forwarded to a Network Server."
+        },
+        "downlink_count": {
+          "type": "string",
+          "format": "uint64",
+          "description": "Number of downlink messages forwarded."
+        }
+      },
+      "description": "Link stats as monitored by the Application Server."
+    },
     "v3ApplicationLocation": {
       "type": "object",
       "properties": {

api/applicationserver.proto

@@ -19,6 +19,7 @@ import "github.com/mwitkow/go-proto-validators/validator.proto";
 import "google/api/annotations.proto";
 import "google/protobuf/empty.proto";
 import "google/protobuf/field_mask.proto";
+import "google/protobuf/timestamp.proto";
 import "lorawan-stack/api/end_device.proto";
 import "lorawan-stack/api/identifiers.proto";
 import "lorawan-stack/api/messages.proto";
@@ -48,6 +49,21 @@ message SetApplicationLinkRequest {
   google.protobuf.FieldMask field_mask = 3 [(gogoproto.nullable) = false];
 }
 
+// Link stats as monitored by the Application Server.
+message ApplicationLinkStats {
+  google.protobuf.Timestamp linked_at = 1 [(gogoproto.stdtime) = true];
+  string network_server_address = 2;
+  // Timestamp when the last upstream message has been received from a Network Server.
+  // This can be a join-accept, uplink message or downlink message event.
+  google.protobuf.Timestamp last_up_received_at = 3 [(gogoproto.stdtime) = true];
+  // Number of upstream messages received.
+  uint64 up_count = 4;
+  // Timestamp when the last downlink message has been forwarded to a Network Server.
+  google.protobuf.Timestamp last_downlink_forwarded_at = 5 [(gogoproto.stdtime) = true];
+  // Number of downlink messages forwarded.
+  uint64 downlink_count = 6;
+}
+
 // The As service manages the Application Server.
 service As {
   rpc GetLink(GetApplicationLinkRequest) returns (ApplicationLink) {
@@ -68,6 +84,12 @@ service As {
       delete: "/as/applications/{application_id}/link",
     };
   };
+
+  rpc GetLinkStats(ApplicationIdentifiers) returns (ApplicationLinkStats) {
+    option (google.api.http) = {
+      get: "/as/applications/{application_id}/link/stats"
+    };
+  };
 }
 
 // The AppAs service connects an application or integration to an Application Server.

api/gatewayserver.proto

@@ -15,6 +15,7 @@
 syntax = "proto3";
 
 import "github.com/gogo/protobuf/gogoproto/gogo.proto";
+import "google/api/annotations.proto";
 import "google/protobuf/duration.proto";
 import "google/protobuf/empty.proto";
 import "lorawan-stack/api/gateway.proto";
@@ -63,5 +64,9 @@ service NsGs {
 service Gs {
   // Get statistics about the current gateway connection to the Gateway Server.
   // This is not persisted between reconnects.
-  rpc GetGatewayConnectionStats(GatewayIdentifiers) returns (GatewayConnectionStats);
+  rpc GetGatewayConnectionStats(GatewayIdentifiers) returns (GatewayConnectionStats) {
+    option (google.api.http) = {
+      get: "/gs/gateways/{gateway_id}/connection/stats"
+    };
+  };
 }

config/messages.json

@@ -4760,6 +4760,24 @@
       "file": "observability.go"
     }
   },
+  "event:as.link.start": {
+    "translations": {
+      "en": "link start"
+    },
+    "description": {
+      "package": "pkg/applicationserver",
+      "file": "observability.go"
+    }
+  },
+  "event:as.link.stop": {
+    "translations": {
+      "en": "link stop"
+    },
+    "description": {
+      "package": "pkg/applicationserver",
+      "file": "observability.go"
+    }
+  },
   "event:as.up.data.decode.fail": {
     "translations": {
       "en": "decode uplink data message fail"

pkg/applicationserver/applicationserver.go

@@ -20,6 +20,7 @@ import (
 	"fmt"
 	"net"
 	"sync"
+	"sync/atomic"
 	"time"
 
 	pbtypes "github.com/gogo/protobuf/types"
@@ -229,6 +230,7 @@ func (as *ApplicationServer) downlinkQueueOp(ctx context.Context, ids ttnpb.EndD
 		return err
 	}
 	<-link.connReady
+	var encryptedItems []*ttnpb.ApplicationDownlink
 	_, err = as.deviceRegistry.Set(ctx, ids,
 		[]string{
 			"session",
@@ -254,29 +256,29 @@ func (as *ApplicationServer) downlinkQueueOp(ctx context.Context, ids ttnpb.EndD
 				item.DecodedPayload = nil
 				item.CorrelationIDs = events.CorrelationIDsFromContext(ctx)
 				dev.Session.LastAFCntDown = item.FCnt
+				encryptedItems = append(encryptedItems, item)
 			}
 			client := ttnpb.NewAsNsClient(link.conn)
 			req := &ttnpb.DownlinkQueueRequest{
 				EndDeviceIdentifiers: ids,
-				Downlinks:            items,
+				Downlinks:            encryptedItems,
 			}
 			_, err = op(client, ctx, req, link.callOpts...)
 			if err != nil {
-				for _, item := range items {
-					registerDropDownlink(ctx, ids, item, err)
-				}
 				return nil, nil, err
 			}
-			for _, item := range items {
-				registerForwardDownlink(ctx, ids, item, link.connName)
-			}
 			return dev, []string{"session.last_a_f_cnt_down"}, nil
 		},
 	)
 	if err != nil {
+		for _, item := range encryptedItems {
+			registerDropDownlink(ctx, ids, item, err)
+		}
 		return err
 	}
-	for _, item := range items {
+	atomic.AddUint64(&link.downlinks, uint64(len(encryptedItems)))
+	atomic.StoreInt64(&link.lastDownlinkTime, time.Now().UnixNano())
+	for _, item := range encryptedItems {
 		registerForwardDownlink(ctx, ids, item, link.connName)
 	}
 	return nil

pkg/applicationserver/grpc_as.go

@@ -75,3 +75,30 @@ func (as *ApplicationServer) DeleteLink(ctx context.Context, ids *ttnpb.Applicat
 	}
 	return ttnpb.Empty, nil
 }
+
+// GetLinkStats implements ttnpb.AsServer.
+func (as *ApplicationServer) GetLinkStats(ctx context.Context, ids *ttnpb.ApplicationIdentifiers) (*ttnpb.ApplicationLinkStats, error) {
+	if err := rights.RequireApplication(ctx, *ids, ttnpb.RIGHT_APPLICATION_LINK); err != nil {
+		return nil, err
+	}
+
+	link, err := as.getLink(ctx, *ids)
+	if err != nil {
+		return nil, err
+	}
+	<-link.connReady
+
+	stats := &ttnpb.ApplicationLinkStats{}
+	lt := link.GetLinkTime()
+	stats.LinkedAt = &lt
+	stats.NetworkServerAddress = link.NetworkServerAddress
+	if n, t, ok := link.GetUpStats(); ok {
+		stats.UpCount = n
+		stats.LastUpReceivedAt = &t
+	}
+	if n, t, ok := link.GetDownlinkStats(); ok {
+		stats.DownlinkCount = n
+		stats.LastDownlinkForwardedAt = &t
+	}
+	return stats, nil
+}