cmd/lncli: add --peer flag to list channels

This commit adds a flag to listchannels that filters by remote pubkey.

cmd/lncli/commands.go

@@ -1990,6 +1990,12 @@ var listChannelsCommand = cli.Command{
 			Name:  "private_only",
 			Usage: "only list channels which are currently private",
 		},
+		cli.StringFlag{
+			Name: "peer",
+			Usage: "(optional) only display channels with a " +
+				"particular peer, accepts 66-byte, " +
+				"hex-encoded pubkeys",
+		},
 	},
 	Action: actionDecorator(listChannels),
 }
@@ -1999,11 +2005,26 @@ func listChannels(ctx *cli.Context) error {
 	client, cleanUp := getClient(ctx)
 	defer cleanUp()
 
+	peer := ctx.String("peer")
+
+	// If the user requested channels with a particular key, parse the
+	// provided pubkey.
+	var peerKey []byte
+	if len(peer) > 0 {
+		pk, err := route.NewVertexFromStr(peer)
+		if err != nil {
+			return fmt.Errorf("invalid --peer pubkey: %v", err)
+		}
+
+		peerKey = pk[:]
+	}
+
 	req := &lnrpc.ListChannelsRequest{
 		ActiveOnly:   ctx.Bool("active_only"),
 		InactiveOnly: ctx.Bool("inactive_only"),
 		PublicOnly:   ctx.Bool("public_only"),
 		PrivateOnly:  ctx.Bool("private_only"),
+		Peer:         peerKey,
 	}
 
 	resp, err := client.ListChannels(ctxb, req)
@@ -2011,8 +2032,6 @@ func listChannels(ctx *cli.Context) error {
 		return err
 	}
 
-	// TODO(roasbeef): defer close the client for the all
-
 	printRespJSON(resp)
 
 	return nil

lnrpc/rpc.proto

@@ -1385,6 +1385,12 @@ message ListChannelsRequest {
     bool inactive_only = 2;
     bool public_only = 3;
     bool private_only = 4;
+
+    /**
+    Filters the response for channels with a target peer's pubkey. If peer is
+    empty, all channels will be returned.
+    */
+    bytes peer = 5;
 }
 message ListChannelsResponse {
     /// The list of active channels

lnrpc/rpc.swagger.json

@@ -116,6 +116,14 @@
             "required": false,
             "type": "boolean",
             "format": "boolean"
+          },
+          {
+            "name": "peer",
+            "description": "*\nFilters the response for channels with a target peer's pubkey. If peer is\nempty, all channels will be returned.",
+            "in": "query",
+            "required": false,
+            "type": "string",
+            "format": "byte"
           }
         ],
         "tags": [

rpcserver.go

@@ -2948,6 +2948,11 @@ func (r *rpcServer) ListChannels(ctx context.Context,
 			"`private_only` can be set, but not both")
 	}
 
+	if len(in.Peer) > 0 && len(in.Peer) != 33 {
+		_, err := route.NewVertexFromBytes(in.Peer)
+		return nil, fmt.Errorf("invalid `peer` key: %v", err)
+	}
+
 	resp := &lnrpc.ListChannelsResponse{}
 
 	graph := r.server.chanDB.ChannelGraph()
@@ -2962,8 +2967,15 @@ func (r *rpcServer) ListChannels(ctx context.Context,
 
 	for _, dbChannel := range dbChannels {
 		nodePub := dbChannel.IdentityPub
+		nodePubBytes := nodePub.SerializeCompressed()
 		chanPoint := dbChannel.FundingOutpoint
 
+		// If the caller requested channels for a target node, skip any
+		// that don't match the provided pubkey.
+		if len(in.Peer) > 0 && !bytes.Equal(nodePubBytes, in.Peer) {
+			continue
+		}
+
 		var peerOnline bool
 		if _, err := r.server.FindPeer(nodePub); err == nil {
 			peerOnline = true