Adding Sentinel Commands

sentinel.go

@@ -0,0 +1,301 @@
+package goredis
+
+import (
+	"fmt"
+	"log"
+	"reflect"
+	"strconv"
+)
+
+// MasterAddress is a small struct to provide connection information for a
+// Master as returned from get-master-addr-by-name
+type MasterAddress struct {
+	Host string
+	Port int
+}
+
+// MasterInfo is a struct providing the information available from sentinel
+// about a given master (aka pod)
+// The way this works is you tag the field with the name redis returns
+// and reflect is used in the methods which return this structure to populate
+// it with the data from Redis
+//
+// Note this means it will nee dto be updated when new fields are added in
+// sentinel. Fortunately this appears to be rare.
+//
+// Currently the list is:
+// 'pending-commands'
+// 'ip'
+// 'down-after-milliseconds'
+// 'role-reported'
+// 'runid'
+// 'port'
+// 'last-ok-ping-reply'
+// 'last-ping-sent'
+// 'failover-timeout'
+// 'config-epoch'
+// 'quorum'
+// 'role-reported-time'
+// 'last-ping-reply'
+// 'name'
+// 'parallel-syncs'
+// 'info-refresh'
+// 'flags'
+// 'num-slaves'
+// 'num-other-sentinels'
+type MasterInfo struct {
+	Name                  string `redis:"name"`
+	Port                  int    `redis:"port"`
+	NumSlaves             int    `redis:"num-slaves"`
+	Quorum                int    `redis:"quorum"`
+	NumOtherSentinels     int    `redis:"num-other-sentinels"`
+	ParallelSyncs         int    `redis:"parallel-syncs"`
+	Runid                 string `redis:"runid"`
+	IP                    string `redis:"ip"`
+	DownAfterMilliseconds int    `redis:"down-after-milliseconds"`
+	IsMasterDown          bool   `redis:"is-master-down"`
+	LastOkPingReply       int    `redis:"last-ok-ping-reply"`
+	RoleReportedTime      int    `redis:"role-reported-time"`
+	InfoRefresh           int    `redis:"info-refresh"`
+	RoleReported          string `redis:"role-reported"`
+	LastPingReply         int    `redis:"last-ping-reply"`
+	LastPingSent          int    `redis:"last-ping-sent"`
+	FailoverTimeout       int    `redis:"failover-timeout"`
+	ConfigEpoch           int    `redis:"config-epoch"`
+	Flags                 string `redis:"flags"`
+}
+
+// SlaveInfo is a struct for the results returned from slave queries,
+// specifically the individual entries of the  `sentinel slave <podname>`
+// command. As with the other Sentinel structs this may change and will need
+// updated for new entries
+// Currently the members defined by sentinel are as follows.
+// "name"
+// "ip"
+// "port"
+// "runid"
+// "flags"
+// "pending-commands"
+// "last-ping-sent"
+// "last-ok-ping-reply"
+// "last-ping-reply"
+// "down-after-milliseconds"
+// "info-refresh"
+// "role-reported"
+// "role-reported-time"
+// "master-link-down-time"
+// "master-link-status"
+// "master-host"
+// "master-port"
+// "slave-priority"
+// "slave-repl-offset"
+type SlaveInfo struct {
+	Name                   string `redis:"name"`
+	Host                   string `redis:"ip"`
+	Port                   int    `redis:"port"`
+	Runid                  string `redis:"runid"`
+	Flags                  string `redis:"flags"`
+	PendingCommands        int    `redis:"pending-commands"`
+	IsMasterDown           bool   `redis:"is-master-down"`
+	LastOkPingReply        int    `redis:"last-ok-ping-reply"`
+	RoleReportedTime       int    `redis:"role-reported-time"`
+	LastPingReply          int    `redis:"last-ping-reply"`
+	LastPingSent           int    `redis:"last-ping-sent"`
+	InfoRefresh            int    `redis:"info-refresh"`
+	RoleReported           string `redis:"role-reported"`
+	MasterLinkDownTime     int    `redis:"master-link-down-time"`
+	MasterLinkStatus       string `redis:"master-link-status"`
+	MasterHost             string `redis:"master-host"`
+	MasterPort             int    `redis:"master-port"`
+	SlavePriority          int    `redis:"slave-priority"`
+	SlaveReplicationOffset int    `redis:"slave-repl-offset"`
+}
+
+// buildSlaveInfoStruct builods the struct for a slave from the Redis slaves command
+func (r *Redis) buildSlaveInfoStruct(info map[string]string) (master SlaveInfo, err error) {
+	s := reflect.ValueOf(&master).Elem()
+	typeOfT := s.Type()
+	for i := 0; i < s.NumField(); i++ {
+		p := typeOfT.Field(i)
+		f := s.Field(i)
+		tag := p.Tag.Get("redis")
+		if f.Type().Name() == "int" {
+			val, err := strconv.ParseInt(info[tag], 10, 64)
+			if err != nil {
+				println("Unable to convert to data from sentinel server:", info[tag], err)
+			} else {
+				f.SetInt(val)
+			}
+		}
+		if f.Type().Name() == "string" {
+			f.SetString(info[tag])
+		}
+		if f.Type().Name() == "bool" {
+			// This handles primarily the xxx_xx style fields in the return data from redis
+			if info[tag] != "" {
+				val, err := strconv.ParseInt(info[tag], 10, 64)
+				if err != nil {
+					println("[bool] Unable to convert to data from sentinel server:", info[tag], err)
+					fmt.Println("Error:", err)
+				} else {
+					if val > 0 {
+						f.SetBool(true)
+					}
+				}
+			}
+		}
+	}
+	return
+}
+
+// SentinelSlaves takes a podname and returns a list of SlaveInfo structs for
+// each known slave.
+func (r *Redis) SentinelSlaves(podname string) (slaves []SlaveInfo) {
+	rp, err := r.ExecuteCommand("SENTINEL", "SLAVES", podname)
+	if err != nil {
+		fmt.Println("error on slaves command:", err)
+		return
+	}
+	for i := 0; i < len(rp.Multi); i++ {
+		slavemap, err := rp.Multi[i].HashValue()
+		if err != nil {
+			log.Println("unable to get slave info, err:", err)
+		} else {
+			info, err := r.buildSlaveInfoStruct(slavemap)
+			if err != nil {
+				fmt.Printf("Unable to get slaves, err:", err, "\n")
+			}
+			slaves = append(slaves, info)
+		}
+	}
+	return
+}
+
+// SentinelMonitor executes the SENTINEL MONITOR command on the server
+// This is used to add pods to the sentinel configuration
+func (r *Redis) SentinelMonitor(podname string, ip string, port int, quorum int) error {
+	_, err := r.ExecuteCommand("SENTINEL", "MONITOR", podname, ip, port, quorum)
+	return err
+}
+
+// SentinelRemove executes the SENTINEL REMOVE command on the server
+// This is used to remove pods to the sentinel configuration
+func (r *Redis) SentinelRemove(podname string) error {
+	_, err := r.ExecuteCommand("SENTINEL", "REMOVE", podname)
+	return err
+}
+
+// SentinelSetString will set the value of skey to sval for a
+// given pod. This is used when the value is known to be a string
+func (r *Redis) SentinelSetString(podname string, skey string, sval string) error {
+	_, err := r.ExecuteCommand("SENTINEL", "SET", podname, skey, sval)
+	return err
+}
+
+// SentinelSetInt will set the value of skey to sval for a
+// given pod. This is used when the value is known to be an Int
+func (r *Redis) SentinelSetInt(podname string, skey string, sval int) error {
+	_, err := r.ExecuteCommand("SENTINEL", "SET", podname, skey, sval)
+	return err
+}
+
+// SentinelSetPass will set the value to be used in the AUTH command for a
+// given pod
+func (r *Redis) SentinelSetPass(podname string, password string) error {
+	_, err := r.ExecuteCommand("SENTINEL", "SET", podname, "AUTHPASS", password)
+	return err
+}
+
+func (r *Redis) SentinelMasters() (masters []MasterInfo, err error) {
+	rp, err := r.ExecuteCommand("SENTINEL", "MASTERS")
+	if err != nil {
+		return
+	}
+	podcount := len(rp.Multi)
+	for i := 0; i < podcount; i++ {
+		pod, err := rp.Multi[i].HashValue()
+		if err != nil {
+			log.Fatal("Error:", err)
+		}
+		minfo, err := r.buildMasterInfoStruct(pod)
+		masters = append(masters, minfo)
+	}
+	return
+}
+
+func (r *Redis) buildMasterInfoStruct(info map[string]string) (master MasterInfo, err error) {
+	s := reflect.ValueOf(&master).Elem()
+	typeOfT := s.Type()
+	for i := 0; i < s.NumField(); i++ {
+		p := typeOfT.Field(i)
+		f := s.Field(i)
+		tag := p.Tag.Get("redis")
+		if f.Type().Name() == "int" {
+			val, err := strconv.ParseInt(info[tag], 10, 64)
+			if err != nil {
+				fmt.Println("Unable to convert to integer from sentinel server:", tag, info[tag], err)
+			} else {
+				f.SetInt(val)
+			}
+		}
+		if f.Type().Name() == "string" {
+			f.SetString(info[tag])
+		}
+		if f.Type().Name() == "bool" {
+			// This handles primarily the xxx_xx style fields in the return data from redis
+			if info[tag] != "" {
+				val, err := strconv.ParseInt(info[tag], 10, 64)
+				if err != nil {
+					println("Unable to convert to bool from sentinel server:", info[tag])
+					fmt.Println(info[tag])
+					fmt.Println("Error:", err)
+				} else {
+					if val > 0 {
+						f.SetBool(true)
+					}
+				}
+			}
+		}
+	}
+	return
+}
+
+// SentinelMasterInfo returns the information about a pod or master
+func (r *Redis) SentinelMasterInfo(podname string) (master MasterInfo, err error) {
+	rp, err := r.ExecuteCommand("SENTINEL", "MASTER", podname)
+	if err != nil {
+		return master, err
+	}
+	info, err := rp.HashValue()
+	return r.buildMasterInfoStruct(info)
+}
+
+// SentinelGetMaster returns the information needed to connect to the master of
+// a given pod
+func (r *Redis) SentinelGetMaster(podname string) (conninfo MasterAddress, err error) {
+	rp, err := r.ExecuteCommand("SENTINEL", "get-master-addr-by-name", podname)
+	if err != nil {
+		return conninfo, err
+	}
+	info, err := rp.ListValue()
+	conninfo.Host = info[0]
+	conninfo.Port, err = strconv.Atoi(info[1])
+	if err != nil {
+		fmt.Println("Got bad port info from server, causing err:", err)
+	}
+	return conninfo, err
+}
+
+func (r *Redis) SentinelFailover(podname string) (bool, error) {
+	rp, err := r.ExecuteCommand("SENTINEL", "failover", podname)
+	if err != nil {
+		log.Println("Error on failover command execution:", err)
+		return false, err
+	}
+
+	if rp.Error != "" {
+		log.Println("Error on failover command execution:", rp.Error)
+		return false, fmt.Errorf("Unable to failover pod '%s' due to error: '%s'", podname, rp.Error)
+	}
+	return true, nil
+}