update xds-server package in docker

scripts/package-update: bash scripts to update xds-server package in docker
monitor updates: default time is 24h, a update is tried at startup
api/v1: 2 new requests:
    - get(updates): return various information about xds-server packages
    - post(updates): update xds-server packages

Change-Id: I1673f7860e57cfe1d4abe5a24609ee46a90b67d8
Signed-off-by: Clément Bénier <clement.benier@iot.bzh>

1 files changed, 164 insertions, 0 deletions

diff --git a/lib/xdsserver/xds-server-update.go b/lib/xdsserver/xds-server-update.go
new file mode 100644
index 0000000..cd9d6b1
--- /dev/null
+++ b/lib/xdsserver/xds-server-update.go
@@ -0,0 +1,164 @@
+/*
+ * Copyright (C) 2018 "IoT.bzh"
+ * Author Clément Bénier <clement.benier@iot.bzh>
+ *
+ * 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 xdsserver
+
+import (
+	"os/exec"
+	"path"
+	"path/filepath"
+	"strings"
+	sc "sync"
+	"time"
+
+	common "gerrit.automotivelinux.org/gerrit/src/xds/xds-common.git/golib"
+	"gerrit.automotivelinux.org/gerrit/src/xds/xds-server/lib/xdsconfig"
+	"gerrit.automotivelinux.org/gerrit/src/xds/xds-server/lib/xsapiv1"
+)
+
+const (
+	scriptXdsSrvUpdate    = "updateXdsServerPackage"
+	scriptGetXdsSrvUpdate = "getXdsServerPackage"
+	scriptXdsSrvRestart   = "restartXdsServer"
+)
+
+//LockXdsUpdate allows to lock xds-server avoiding restart
+type LockXdsUpdate struct {
+	sc.Mutex
+	LockCpt int
+}
+
+//LockXdsUpdateCounter Inc/decrement lock counter
+func LockXdsUpdateCounter(ctx *Context, inc bool) {
+	if inc {
+		//paranoia lock count > 10
+		if ctx.lockXdsSrvUpdate.LockCpt > 10 {
+			ctx.Log.Errorf("lock counter value is abnormally high: LockCpt=%v", ctx.lockXdsSrvUpdate.LockCpt)
+		}
+		ctx.lockXdsSrvUpdate.Lock()
+		ctx.lockXdsSrvUpdate.LockCpt++
+		ctx.lockXdsSrvUpdate.Unlock()
+	} else {
+		//paranoia lock count < 0
+		if ctx.lockXdsSrvUpdate.LockCpt <= 0 {
+			ctx.Log.Errorf("lock counter value is lower than 0: LockCpt=%v", ctx.lockXdsSrvUpdate.LockCpt)
+			return
+		}
+		ctx.lockXdsSrvUpdate.Lock()
+		ctx.lockXdsSrvUpdate.LockCpt--
+		ctx.lockXdsSrvUpdate.Unlock()
+	}
+}
+
+//MonitorUpdates try to update xds-server package at first
+// then monitor updates
+func MonitorUpdates(ctx *Context) {
+	UpdateXdsServer(ctx) //try to update at startup
+
+	updateTime, err := time.ParseDuration(ctx.Config.FileConf.XdsSrvUpdateTime)
+	if err != nil {
+		ctx.Log.Errorf("Wrong format type of XdsSrvUpdateTime\n"+
+			"err=%v \n"+
+			"Valid time units are ns, us, ms, s, m, h\n"+
+			"Here an example: 1h10m10s\n"+
+			"So, default value is set %v", err, xdsconfig.DefaultXdsSrvUpdateTime)
+		updateTime, _ = time.ParseDuration(xdsconfig.DefaultXdsSrvUpdateTime)
+	}
+	ctx.Log.Infof("Update time for package xds-server is %v", updateTime)
+	go func(ctx *Context) {
+		for {
+			currentUpdateTime := updateTime
+			for currentUpdateTime > 0 {
+				time.Sleep(currentUpdateTime)
+				currentUpdateTime = UpdateXdsServer(ctx)
+			}
+		}
+	}(ctx)
+}
+
+func getScriptsDir(ctx *Context) string {
+	scriptsDir := ctx.Config.FileConf.XdsUtilsScriptsDir
+	if !common.Exists(scriptsDir) {
+		// allow to use scripts/xds-utils when debugging with vscode(EXEPATH=WORKSPACE)
+		scriptsDir = filepath.Join(filepath.Dir(ctx.Config.FileConf.XdsUtilsScriptsDir), "scripts", "xds-utils")
+		if !common.Exists(scriptsDir) {
+			ctx.Log.Errorf("scripts directory doesn't exist (%v)", scriptsDir)
+		}
+	}
+	return scriptsDir
+}
+
+// UpdateXdsServer launches update package xds-server script
+func UpdateXdsServer(ctx *Context) time.Duration {
+	timeToRestartIfBusy := 0 * time.Minute
+	scriptsDir := getScriptsDir(ctx)
+
+	ctx.Log.Infof("Trying to update xds-server package, "+
+		"xds-utils scripts dir: %s", scriptsDir)
+
+	//launch xds-server update package script
+	cmd := exec.Command(path.Join(scriptsDir, scriptXdsSrvUpdate))
+	_, err := cmd.CombinedOutput()
+	if err != nil {
+		ctx.Log.Errorf("Cannot update xds-server package err=%v", err)
+		return 0
+	}
+
+	//launch xds-server restart script
+	cmd = exec.Command(path.Join(scriptsDir, scriptXdsSrvRestart))
+	ctx.lockXdsSrvUpdate.Lock()
+	if ctx.lockXdsSrvUpdate.LockCpt == 0 { //no action in progress
+		_, err = cmd.CombinedOutput()
+		if err != nil {
+			ctx.Log.Errorf("Cannot restart xds-server service err=%v", err)
+			return 0
+		}
+	} else {
+		timeToRestartIfBusy = 1 * time.Minute
+		ctx.Log.Infof("Cannot restart xds-server service because "+
+			"xds-server has an action in progress, trying to restart in a %v", timeToRestartIfBusy)
+	}
+	ctx.lockXdsSrvUpdate.Unlock()
+
+	return timeToRestartIfBusy
+}
+
+// GetXdsSrvUpdate gets information about package
+func GetXdsSrvUpdate(ctx *Context) xsapiv1.XdsSrvUpdate {
+	var xdsSrvUpdate xsapiv1.XdsSrvUpdate
+	scriptsDir := getScriptsDir(ctx)
+
+	//exec getXdsSrvUpdate script
+	cmd := exec.Command(path.Join(scriptsDir, scriptGetXdsSrvUpdate))
+	stdout, err := cmd.CombinedOutput()
+	if err != nil {
+		ctx.Log.Errorf("Cannot get xds-server package information err=%v", err)
+		return xdsSrvUpdate
+	}
+
+	//stdout is formatting with 'version: xxxxx'
+	outputs := strings.Split(string(stdout[:]), "\n")
+	installedVersion := strings.Split(outputs[0], ": ")[1]
+	candidateVersion := strings.Split(outputs[1], ": ")[1]
+	ctx.Log.Infof("XdsSrvUpdate: candidateVersion:%v installedVersion:%v", candidateVersion, installedVersion)
+	xdsSrvUpdate = xsapiv1.XdsSrvUpdate{
+		CurrentVersion: installedVersion,
+		NewerVersion:   candidateVersion,
+		UpdateTime:     ctx.Config.FileConf.XdsSrvUpdateTime,
+	}
+	return xdsSrvUpdate
+}