From d56c5bac1426268d579b42e8297a21e1f856daa7 Mon Sep 17 00:00:00 2001
From: Denis Zheleztsov <d_zheleztsov@wargaming.net>
Date: Mon, 9 Jan 2017 22:32:00 +0300
Subject: [PATCH] requests

---
 src/rbmd/requests.go | 163 +++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 163 insertions(+)
 create mode 100644 src/rbmd/requests.go

diff --git a/src/rbmd/requests.go b/src/rbmd/requests.go
new file mode 100644
index 0000000..71b1514
--- /dev/null
+++ b/src/rbmd/requests.go
@@ -0,0 +1,163 @@
+package rbmd
+
+import (
+	"log"
+	"strings"
+	"encoding/json"
+	// "bytes"
+
+	"github.com/samuel/go-zookeeper/zk"
+)
+
+//RequestWatch watch for mount/umount requests
+func (z ZooNode) RequestWatch(fqdn string) {
+	requestsPath := strings.Join([]string{z.Path, "cluster", fqdn, "requests"}, "/")
+	_, _, ch, err := z.Conn.ChildrenW(requestsPath)
+	if err != nil {
+		log.Print("[zk ERROR] ", err)
+	}
+
+	for {
+		req := <-ch
+		log.Print("[DEBUG] ch path ", req.Path)
+		childrens, _, err := z.Conn.Children(requestsPath)
+		if err != nil {
+			break
+		}
+		for _, child := range childrens {
+			p := strings.Join([]string{req.Path, child}, "/")
+			request, _, err := z.Conn.Get(p)
+			if err != nil {
+				log.Print("[zk ERROR] ", err)
+			}
+
+			var r RBDDevice
+			err = json.Unmarshal(request, &r)
+			if err != nil {
+				log.Print("[ERROR] ", err)
+			}
+
+			// 1) Map RBD 2) Mount FS
+			if child == "mount" {
+				std, err := r.MapDevice()
+				if err != nil {
+					z.RMR(p)
+					z.Answer(fqdn, child, std, "FAIL")
+					log.Print("[ERROR] Mapping error: ", string(std), err)
+					break
+				}
+				err = r.MountFS(string(std))
+				if err != nil {
+					r.UnmapDevice()
+					z.RMR(p)
+					z.Answer(fqdn, child, std, "FAIL")
+					log.Print("[ERROR] Mount filesystem error: ", err)
+					break
+				}
+				z.Answer(fqdn, child, std, "OK")
+			// 1) Unmount FS 2) Unmap RBD
+			} else if child == "umount" {
+				log.Print("[DEBUG] Umount")
+			} else {
+				log.Print("[DEBUG] Unknown ", child)
+			}
+			z.RMR(p)
+		}
+		break
+	}
+}
+
+//Answer make answer
+func (z ZooNode) Answer(fqdn string, req string, stderr []byte, t string) {
+	answerPath := strings.Join([]string{z.Path, "cluster", fqdn, "answers", req}, "/")
+
+	answer := MountState{t, string(stderr)}
+	answerJSON, err := json.Marshal(answer)
+	if err != nil {
+		log.Print("[ERROR] ", err)
+	}
+
+	_, err = z.Conn.Create(answerPath, answerJSON, 0, zk.WorldACL(zk.PermAll))
+	if err != nil {
+		log.Print("[zk ERROR] ", err)
+		_, err := z.Conn.Set(answerPath, answerJSON, -1)
+		if err != nil {
+			log.Print("[zk ERROR] ", err)
+		}
+	}
+}
+
+//MountRequest write mount request
+// func (z ZooNode) MountRequest(RBDDevice) {
+	
+// }
+
+//MountRequest create node with mount requests from API
+func (z ZooNode) MountRequest(r RBDDevice) error {
+	jsReq, err := json.Marshal(r)
+	if err != nil {
+		return err
+	}
+
+	requestsPath := strings.Join([]string{z.Path, "cluster", r.Node, "requests", "mount"}, "/")
+	_, err = z.Conn.Create(requestsPath, jsReq, 0, zk.WorldACL(zk.PermAll))
+	if err != nil {
+		_, err := z.Conn.Set(requestsPath, jsReq, -1)
+		if err != nil {
+			log.Print("[zk ERROR] ", err)
+			return err
+		}
+	}
+	return nil
+}
+
+//WatchAnswer watch for answer
+func (z ZooNode) WatchAnswer(fqdn string, t string) MountState {
+	answersPath := strings.Join([]string{z.Path, "cluster", fqdn, "answers"}, "/")
+	log.Print("[DEBUG] ", answersPath)
+	_, _, ch, err := z.Conn.ChildrenW(answersPath)
+	if err != nil {
+		log.Print("[zk ERROR] 107 ", err)
+	}
+
+	var ms MountState
+	var p string
+	
+	for {
+		ans := <-ch
+		log.Print("[DEBUG] ch answer path ", ans.Path)
+		childrens, _, err := z.Conn.Children(answersPath)
+		if err != nil {
+			ms.Message = "Zk Error"
+			ms.State = "FAIL"
+			break
+		}
+		for _, child := range childrens {
+			p = strings.Join([]string{ans.Path, child}, "/")
+			answer, _, err := z.Conn.Get(p)
+			if err != nil {
+				log.Print("[zk ERROR] ", err)
+				ms.Message = "Zk Error"
+				ms.State = "FAIL"
+				break
+			}
+
+			var m MountState
+			err = json.Unmarshal(answer, &m)
+			if err != nil {
+				log.Print("[ERROR] ", err)
+				ms.Message = "Zk Error"
+				ms.State = "FAIL"
+				break
+			}
+
+			if child == t {
+				ms = m
+				break
+			}
+		}
+		break
+	}
+	z.RMR(p)
+	return ms
+}