query by metaseq and dataseq interface

2026-01-06 03:44:52 +00:00 · 2018-10-03 11:11:19 -07:00
parent 61f8ca8981
commit 145debbdf5
4 changed files with 479 additions and 1 deletions
--- a/examples/count-changes/main.go
+++ b/examples/count-changes/main.go
@@ -0,0 +1,82 @@
+// Copyright (c) 2018 Versity Software, Inc.
+//
+// Use of this source code is governed by a BSD-3-Clause license
+// that can be found in the LICENSE file in the root of the source
+// tree.
+
+package main
+
+import (
+	"fmt"
+	"log"
+	"net/http"
+	"os"
+	"time"
+
+	scoutfs "github.com/versity/scoutfs-go"
+)
+
+const (
+	max32 = 0xffffffff
+	max64 = 0xffffffffffffffff
+)
+
+type server struct {
+	update    <-chan int
+	lastcount int
+}
+
+func queryPopulation(basedir string, update chan<- int) error {
+	h, err := scoutfs.NewQuery(basedir,
+		scoutfs.ByMSeq(scoutfs.InodesEntry{},
+			scoutfs.InodesEntry{Major: max64, Minor: max32, Ino: max64}))
+	if err != nil {
+		return fmt.Errorf("scoutfs new handle: %v", err)
+	}
+	defer h.Close()
+
+	count := 0
+	for {
+		for {
+			qents, err := h.Next()
+			if err != nil {
+				return fmt.Errorf("scoutfs next: %v", err)
+			}
+			if len(qents) == 0 {
+				break
+			}
+			for _, qent := range qents {
+				fmt.Printf("%#v\n", qent)
+				count++
+			}
+		}
+
+		update <- count
+		time.Sleep(500 * time.Millisecond)
+	}
+}
+
+func (s *server) ServeHTTP(w http.ResponseWriter, r *http.Request) {
+	select {
+	case x, ok := <-s.update:
+		if ok {
+			s.lastcount = x
+		} else {
+			fmt.Println("Channel closed!")
+			os.Exit(1)
+		}
+	default:
+	}
+
+	fmt.Fprintf(w, "%s %d", `
+		<HEAD><meta HTTP-EQUIV="REFRESH" content="1"></HEAD>
+		<h1>SCOUTFS</h1></p>
+		Files/Directories updated:`, s.lastcount)
+}
+
+func main() {
+	update := make(chan int, 1)
+	s := &server{update: update}
+	go queryPopulation(os.Args[1], update)
+	log.Fatal(http.ListenAndServe(":8080", s))
+}