Execute PLAN_AGGREGATOR.md

cmd/aggregator/server.go

@@ -0,0 +1,80 @@
+package main
+
+import (
+	"context"
+	"log"
+	"time"
+
+	pb "git.ipng.ch/ipng/nginx-logtail/proto/logtailpb"
+	"google.golang.org/grpc"
+	"google.golang.org/grpc/codes"
+	"google.golang.org/grpc/status"
+)
+
+// Server implements pb.LogtailServiceServer backed by the aggregator Cache.
+type Server struct {
+	pb.UnimplementedLogtailServiceServer
+	cache  *Cache
+	source string
+}
+
+func NewServer(cache *Cache, source string) *Server {
+	return &Server{cache: cache, source: source}
+}
+
+func (srv *Server) TopN(_ context.Context, req *pb.TopNRequest) (*pb.TopNResponse, error) {
+	if req == nil {
+		return nil, status.Error(codes.InvalidArgument, "request is nil")
+	}
+	n := int(req.N)
+	if n <= 0 {
+		n = 10
+	}
+	entries := srv.cache.QueryTopN(req.Filter, req.GroupBy, n, req.Window)
+	resp := &pb.TopNResponse{Source: srv.source}
+	for _, e := range entries {
+		resp.Entries = append(resp.Entries, &pb.TopNEntry{Label: e.Label, Count: e.Count})
+	}
+	return resp, nil
+}
+
+func (srv *Server) Trend(_ context.Context, req *pb.TrendRequest) (*pb.TrendResponse, error) {
+	if req == nil {
+		return nil, status.Error(codes.InvalidArgument, "request is nil")
+	}
+	points := srv.cache.QueryTrend(req.Filter, req.Window)
+	resp := &pb.TrendResponse{Source: srv.source}
+	for _, p := range points {
+		resp.Points = append(resp.Points, &pb.TrendPoint{
+			TimestampUnix: p.Timestamp.Unix(),
+			Count:         p.Count,
+		})
+	}
+	return resp, nil
+}
+
+func (srv *Server) StreamSnapshots(_ *pb.SnapshotRequest, stream grpc.ServerStreamingServer[pb.Snapshot]) error {
+	ch := srv.cache.Subscribe()
+	defer srv.cache.Unsubscribe(ch)
+
+	log.Printf("server: new StreamSnapshots subscriber")
+	for {
+		select {
+		case <-stream.Context().Done():
+			log.Printf("server: StreamSnapshots subscriber disconnected")
+			return nil
+		case snap, ok := <-ch:
+			if !ok {
+				return nil
+			}
+			msg := &pb.Snapshot{Source: srv.source, Timestamp: snap.Timestamp.Unix()}
+			for _, e := range snap.Entries {
+				msg.Entries = append(msg.Entries, &pb.TopNEntry{Label: e.Label, Count: e.Count})
+			}
+			if err := stream.Send(msg); err != nil {
+				return err
+			}
+		case <-time.After(30 * time.Second):
+		}
+	}
+}