pings record to sqlite

cmd/pinger/main.go

@@ -2,12 +2,17 @@ package main
 
 import (
 	"context"
+	"database/sql"
 	"flag"
+	"fmt"
 	"log"
+	"math/rand"
+	"net"
 	"os"
+	"sync"
+	"time"
 
 	"gitea.bel.blue/bel/with"
-	"github.com/digineo/go-ping"
 )
 
 func main() {
@@ -16,18 +21,148 @@ func main() {
 	}
 }
 
+type S struct {
+	*sql.DB
+}
+
 func run(ctx context.Context) error {
+	return with.Sqlite(ctx, "/tmp/pinger.db", func(db *sql.DB) error {
+		s := S{
+			DB: db,
+		}
+		if err := s.init(ctx); err != nil {
+			return err
+		}
+
+		wg := &sync.WaitGroup{}
+		defer wg.Wait()
+		for _, foo := range []func(context.Context) error{
+			s.pingAndRecord,
+			s.listen,
+		} {
+			foo := foo
+			wg.Go(func() {
+				if err := foo(ctx); err != nil {
+					panic(err)
+				}
+			})
+		}
+		return ctx.Err()
+	})
+}
+
+func (s S) init(ctx context.Context) error {
+	for _, q := range []string{
+		`CREATE TABLE IF NOT EXISTS "pinger_to" (
+			id NUMBER NOT NULL UNIQUE
+			, addr TEXT NOT NULL UNIQUE
+		)`,
+		`CREATE TABLE IF NOT EXISTS "pinger_pings" (
+			start TIMESTAMP NOT NULL 
+			, ms NUMBER NOT NULL
+			, ok BOOLEAN NOT NULL DEFAULT false
+			, to_id NUMBER 
+			, FOREIGN KEY (to_id) REFERENCES "pinger_to"(id)
+		)`,
+		//`ALTER TABLE "pinger_pings" SET UNLOGGED`,
+	} {
+		if _, err := s.ExecContext(ctx, q); err != nil {
+			return err
+		}
+	}
+	return ctx.Err()
+}
+
+func (S) listen(ctx context.Context) error {
+	return ctx.Err()
+}
+
+func (s S) pingAndRecord(ctx context.Context) error {
+	ctx, can := context.WithCancel(ctx)
+	defer can()
+
 	fs := flag.NewFlagSet(os.Args[0], flag.ContinueOnError)
+	target := fs.String("t", "google.com", "target")
+	port := fs.String("p", "80", "target port")
+	interval := fs.Duration("i", time.Second, "between conns")
 	if err := fs.Parse(os.Args[1:]); err != nil {
 		return err
 	}
 
-	pinger, err := ping.New("", "::")
-	if err != nil {
+	addr := fmt.Sprintf("%s:%s", *target, *port)
+	if _, err := s.ExecContext(ctx, `
+		INSERT INTO "pinger_to" (id, addr)
+		VALUES ($1, $2)
+		ON CONFLICT (addr) DO NOTHING
+	`, rand.Int(), addr); err != nil {
 		return err
 	}
-	defer pinger.Close()
 
-	log.Fatal("RUN")
+	var toId int
+	if row := s.QueryRowContext(ctx, `
+		SELECT id
+		FROM "pinger_to"
+		WHERE addr=$1
+	`, addr); row.Err() != nil {
+		return row.Err()
+	} else if err := row.Scan(&toId); err != nil {
+		return err
+	}
+
+	type record struct {
+		start time.Time
+		ms    time.Duration
+		ok    bool
+	}
+	records := make(chan record, 100)
+	defer close(records)
+	go func() {
+		for record := range records {
+			if _, err := s.ExecContext(ctx, `
+				INSERT INTO "pinger_pings" 
+				(start, ms, ok, to_id)
+				VALUES
+				($1, $2, $3, $4)
+			`, record.start, record.ms.Milliseconds(), record.ok, toId); err != nil {
+				log.Println("!", err)
+			}
+		}
+	}()
+
+	c := time.NewTicker(*interval)
+	go func() {
+		<-ctx.Done()
+		c.Stop()
+	}()
+
+	dialer := &net.Dialer{
+		Timeout: time.Second,
+	}
+
+	for {
+		select {
+		case <-c.C:
+		case <-ctx.Done():
+			return nil
+		}
+		func() {
+			ctx, can := context.WithTimeout(ctx, *interval)
+			defer can()
+			start := time.Now()
+			conn, err := dialer.DialContext(ctx, "tcp", addr)
+			select {
+			case records <- record{
+				start: start,
+				ms:    time.Since(start),
+				ok:    err == nil,
+			}:
+			default:
+			}
+			if err == nil {
+				conn.Close()
+			}
+		}()
+	}
+
 	return ctx.Err()
 }