...G...... [ZBXNEXT-6408] added mongoDB plugin

(cherry picked from commit 4b3dd53b207a0282cd2b0827702b5b1c11e90969)

1 files changed, 92 insertions, 0 deletions

diff --git a/src/go/plugins/mongodb/handler_oplog_stats.go b/src/go/plugins/mongodb/handler_oplog_stats.go
new file mode 100644
index 00000000000..6da5cfe0d95
--- /dev/null
+++ b/src/go/plugins/mongodb/handler_oplog_stats.go
@@ -0,0 +1,92 @@
+/*
+** Zabbix
+** Copyright (C) 2001-2021 Zabbix SIA
+**
+** This program is free software; you can redistribute it and/or modify
+** it under the terms of the GNU General Public License as published by
+** the Free Software Foundation; either version 2 of the License, or
+** (at your option) any later version.
+**
+** This program is distributed in the hope that it will be useful,
+** but WITHOUT ANY WARRANTY; without even the implied warranty of
+** MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+** GNU General Public License for more details.
+**
+** You should have received a copy of the GNU General Public License
+** along with this program; if not, write to the Free Software
+** Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
+**/
+
+package mongodb
+
+import (
+	"encoding/json"
+	"time"
+
+	"gopkg.in/mgo.v2"
+	"gopkg.in/mgo.v2/bson"
+	"zabbix.com/pkg/zbxerr"
+)
+
+type oplogStats struct {
+	TimeDiff int `json:"timediff"` // in seconds
+}
+
+type oplogEntry struct {
+	Timestamp bson.MongoTimestamp `bson:"ts"`
+}
+
+const (
+	oplogReplicaSet  = "oplog.rs"    // the capped collection that holds the oplog for Replica Set Members
+	oplogMasterSlave = "oplog.$main" // oplog for the master-slave configuration
+)
+
+const (
+	sortAsc  = "$natural"
+	sortDesc = "-$natural"
+)
+
+var oplogQuery = bson.M{"ts": bson.M{"$exists": true}}
+
+// oplogStatsHandler
+// https://docs.mongodb.com/manual/reference/method/db.getReplicationInfo/index.html
+func oplogStatsHandler(s Session, _ map[string]string) (interface{}, error) {
+	var (
+		stats           oplogStats
+		opFirst, opLast oplogEntry
+	)
+
+	localDb := s.DB("local")
+
+	for _, collection := range []string{oplogReplicaSet, oplogMasterSlave} {
+		if err := localDb.C(collection).Find(oplogQuery).
+			Sort(sortAsc).Limit(1).
+			SetMaxTime(time.Duration(s.GetMaxTimeMS()) * time.Millisecond).
+			One(&opFirst); err != nil {
+			if err == mgo.ErrNotFound {
+				continue
+			}
+
+			return nil, zbxerr.ErrorCannotFetchData.Wrap(err)
+		}
+
+		if err := localDb.C(collection).Find(oplogQuery).Sort(sortDesc).Limit(1).One(&opLast); err != nil {
+			return nil, zbxerr.ErrorCannotFetchData.Wrap(err)
+		}
+
+		break
+	}
+
+	// BSON has a special timestamp type for internal MongoDB use and is not associated with the regular Date type.
+	// This internal timestamp type is a 64 bit value where:
+	// the most significant 32 bits are a time_t value (seconds since the Unix epoch)
+	// the least significant 32 bits are an incrementing ordinal for operations within a given second.
+	stats.TimeDiff = int(opLast.Timestamp>>32 - opFirst.Timestamp>>32)
+
+	jsonRes, err := json.Marshal(stats)
+	if err != nil {
+		return nil, zbxerr.ErrorCannotMarshalJSON.Wrap(err)
+	}
+
+	return string(jsonRes), nil
+}