mongo_helper.js

// YELIN MONGO UTILS

// get index usage
db.orders.aggregate( [ { $indexStats: { } } ] )

// find connection status
ar status = db.serverStatus()
status.connections

// kill operations taking longer than 5s
db.currentOp().inprog.forEach(
  function(op) {
    if(op.secs_running > 5) db.killOp(op.opid);
  }
)

// find operations taking longer than 5s
db.currentOp().inprog.forEach(
  function(op) {
    if(op.secs_running > 5) printjson(op);
  }
)

// CURRENT CONNECTION COUNT
db.currentOp(true).inprog.reduce(
  (accumulator, connection) => {
    ipaddress = connection.client ? connection.client.split(":")[0] : "Internal";
    accumulator[ipaddress] = (accumulator[ipaddress] || 0) + 1;
    accumulator["TOTAL_CONNECTION_COUNT"]++;
    return accumulator;
  },
  { TOTAL_CONNECTION_COUNT: 0 }
)


db.currentOp(true).inprog.filter(connection => !connection.client).map(connection => connection.desc);


// LIST OF INDEXES
db.getCollectionNames().forEach(function(collection) {
   indexes = db.getCollection(collection).getIndexes();
   print("Indexes for " + collection + ":");
   printjson(indexes);
});

// INDEX STATS
db.listing.aggregate({ $indexStats: { } }).cursor.firstBatch.forEach(function(item) {
  print("Index name                     : " + item.name)
  print("Number of times being accesses : " + item.accesses.ops);
  print("-----------------------------")
});


// get collection size
var collectionNames = db.getCollectionNames(),
  stats = [];
collectionNames.forEach(function (n) {
  stats.push(db[n].stats());
});

// COLLECTION SIZE
for (var c in stats) {
  // skip views
  if (!stats[c]["ns"]) continue;
  print(stats[c]["ns"] + ": " + stats[c]["size"]);
}


// ITEM COUNT IN EACH COLLECTION
db.getCollectionNames().forEach(k => print(db[k].getName(), db[k].count()))