mv folders

client/health/health.go

@@ -0,0 +1,178 @@
+// Copyright 2018 fatedier, fatedier@gmail.com
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package health
+
+import (
+	"context"
+	"errors"
+	"fmt"
+	"net"
+	"net/http"
+	"time"
+
+	"github.com/fatedier/frp/utils/log"
+)
+
+var (
+	ErrHealthCheckType = errors.New("error health check type")
+)
+
+type HealthCheckMonitor struct {
+	checkType      string
+	interval       time.Duration
+	timeout        time.Duration
+	maxFailedTimes int
+
+	// For tcp
+	addr string
+
+	// For http
+	url string
+
+	failedTimes    uint64
+	statusOK       bool
+	statusNormalFn func()
+	statusFailedFn func()
+
+	ctx    context.Context
+	cancel context.CancelFunc
+
+	l log.Logger
+}
+
+func NewHealthCheckMonitor(checkType string, intervalS int, timeoutS int, maxFailedTimes int, addr string, url string,
+	statusNormalFn func(), statusFailedFn func()) *HealthCheckMonitor {
+
+	if intervalS <= 0 {
+		intervalS = 10
+	}
+	if timeoutS <= 0 {
+		timeoutS = 3
+	}
+	if maxFailedTimes <= 0 {
+		maxFailedTimes = 1
+	}
+	ctx, cancel := context.WithCancel(context.Background())
+	return &HealthCheckMonitor{
+		checkType:      checkType,
+		interval:       time.Duration(intervalS) * time.Second,
+		timeout:        time.Duration(timeoutS) * time.Second,
+		maxFailedTimes: maxFailedTimes,
+		addr:           addr,
+		url:            url,
+		statusOK:       false,
+		statusNormalFn: statusNormalFn,
+		statusFailedFn: statusFailedFn,
+		ctx:            ctx,
+		cancel:         cancel,
+	}
+}
+
+func (monitor *HealthCheckMonitor) SetLogger(l log.Logger) {
+	monitor.l = l
+}
+
+func (monitor *HealthCheckMonitor) Start() {
+	go monitor.checkWorker()
+}
+
+func (monitor *HealthCheckMonitor) Stop() {
+	monitor.cancel()
+}
+
+func (monitor *HealthCheckMonitor) checkWorker() {
+	for {
+		ctx, cancel := context.WithDeadline(monitor.ctx, time.Now().Add(monitor.timeout))
+		err := monitor.doCheck(ctx)
+
+		// check if this monitor has been closed
+		select {
+		case <-ctx.Done():
+			cancel()
+			return
+		default:
+			cancel()
+		}
+
+		if err == nil {
+			if monitor.l != nil {
+				monitor.l.Trace("do one health check success")
+			}
+			if !monitor.statusOK && monitor.statusNormalFn != nil {
+				if monitor.l != nil {
+					monitor.l.Info("health check status change to success")
+				}
+				monitor.statusOK = true
+				monitor.statusNormalFn()
+			}
+		} else {
+			if monitor.l != nil {
+				monitor.l.Warn("do one health check failed: %v", err)
+			}
+			monitor.failedTimes++
+			if monitor.statusOK && int(monitor.failedTimes) >= monitor.maxFailedTimes && monitor.statusFailedFn != nil {
+				if monitor.l != nil {
+					monitor.l.Warn("health check status change to failed")
+				}
+				monitor.statusOK = false
+				monitor.statusFailedFn()
+			}
+		}
+
+		time.Sleep(monitor.interval)
+	}
+}
+
+func (monitor *HealthCheckMonitor) doCheck(ctx context.Context) error {
+	switch monitor.checkType {
+	case "tcp":
+		return monitor.doTcpCheck(ctx)
+	case "http":
+		return monitor.doHttpCheck(ctx)
+	default:
+		return ErrHealthCheckType
+	}
+}
+
+func (monitor *HealthCheckMonitor) doTcpCheck(ctx context.Context) error {
+	// if tcp address is not specified, always return nil
+	if monitor.addr == "" {
+		return nil
+	}
+
+	var d net.Dialer
+	conn, err := d.DialContext(ctx, "tcp", monitor.addr)
+	if err != nil {
+		return err
+	}
+	conn.Close()
+	return nil
+}
+
+func (monitor *HealthCheckMonitor) doHttpCheck(ctx context.Context) error {
+	req, err := http.NewRequest("GET", monitor.url, nil)
+	if err != nil {
+		return err
+	}
+	resp, err := http.DefaultClient.Do(req)
+	if err != nil {
+		return err
+	}
+
+	if resp.StatusCode/100 != 2 {
+		return fmt.Errorf("do http health check, StatusCode is [%d] not 2xx", resp.StatusCode)
+	}
+	return nil
+}