-
Type:
Bug
-
Resolution: Done
-
Priority:
Major - P3
-
Affects Version/s: 2.0.33
-
Component/s: None
-
Environment:node v0.10.33
MongoDB v2.6.3
Amazon Linux
-
Empty show more show less
Sorry, but couldn't find specific information about differences between Cursor.next() and Cursor.nextObject() for version 2.0 regarding tailable cursors. From the documentation I was expecting that they would behave the same, being only a method rename. What happens is that Cursor.next() constantly returns "MongoError: No more documents in tailed cursor". Well, seems to me that this turns it into a normal cursor, which instead of returning a null item, returns an error. If I set the awaitData option, it waits for some data, but still returns the same error after awhile.
Maybe I'm supposed to use it in a different way, maybe change some timeout?
The following code illustrates the problem:
tailable.js
var mongodb = require('mongodb') mongodb.connect('mongodb://localhost:27017/test', function(err, db) { if (err) throw err; function getCollection (name, cb) { db.collection(name, { strict: true }, function(err, collection) { if (err || !collection) { db.createCollection(name, { size: 1024*1024, capped: true, autoIndexId: true }, cb); } else { cb(null, collection); } }); } getCollection('tailable_test', function (err, tailable_test) { if (err) throw err; tailable_test.insertOne({}, {w:1}, function (err, result) { if (err) throw err; var _id = result.ops[0]._id; console.log('last _id:', _id); var cursor = tailable_test.find({ _id: { $gt: _id } }, { tailable: true, numberOfRetries: Number.MAX_VALUE, tailableRetryInterval: 200 }); var cursorNextObject = cursor.nextObject; var cursorNext = cursor.next; var count = 0; var method; function next() { if (count++ < 5) { cursor.nextObject(function(err, item) { console.log('old nextObject call,', 'error:', err, 'item:', item, 'ts:', new Date().toJSON(), 'count:', count); setTimeout(function () {next()}, 1000) }); } else if (count++ < 20) { cursor.next(function(err, item) { console.log('new next call,', 'error:', err, 'item:', item, 'ts:', new Date().toJSON(), 'count:', count); setTimeout(function () {next()}, 1000) }); } else { process.exit(0); } } next(); setInterval(function () { tailable_test.insertOne({},{w:0}); }, 3000); }); }); })
Unable to find source-code formatter for language: title:output. Available languages are: actionscript, ada, applescript, bash, c, c#, c++, cpp, css, erlang, go, groovy, haskell, html, java, javascript, js, json, lua, none, nyan, objc, perl, php, python, r, rainbow, ruby, scala, sh, sql, swift, visualbasic, xml, yaml
last _id: 556871a19107ccbc136f7fa8 old nextObject call, error: null item: { _id: 556871a49107ccbc136f7fa9 } ts: 2015-05-29T14:03:16.325Z count: 1 old nextObject call, error: null item: { _id: 556871a79107ccbc136f7faa } ts: 2015-05-29T14:03:19.383Z count: 2 old nextObject call, error: null item: { _id: 556871aa9107ccbc136f7fab } ts: 2015-05-29T14:03:22.350Z count: 3 old nextObject call, error: null item: { _id: 556871ad9107ccbc136f7fac } ts: 2015-05-29T14:03:25.423Z count: 4 old nextObject call, error: null item: { _id: 556871b09107ccbc136f7fad } ts: 2015-05-29T14:03:28.485Z count: 5 new next call, error: { [MongoError: No more documents in tailed cursor] name: 'MongoError', message: 'No more documents in tailed cursor', tailable: true, awaitData: undefined } item: undefined ts: 2015-05-29T14:03:29.488Z count: 7 new next call, error: { [MongoError: No more documents in tailed cursor] name: 'MongoError', message: 'No more documents in tailed cursor', tailable: true, awaitData: undefined } item: undefined ts: 2015-05-29T14:03:30.492Z count: 9 new next call, error: null item: { _id: 556871b39107ccbc136f7fae } ts: 2015-05-29T14:03:31.495Z count: 11 new next call, error: { [MongoError: No more documents in tailed cursor] name: 'MongoError', message: 'No more documents in tailed cursor', tailable: true, awaitData: undefined } item: undefined ts: 2015-05-29T14:03:32.498Z count: 13 new next call, error: { [MongoError: No more documents in tailed cursor] name: 'MongoError', message: 'No more documents in tailed cursor', tailable: true, awaitData: undefined } item: undefined ts: 2015-05-29T14:03:33.501Z count: 15 new next call, error: null item: { _id: 556871b69107ccbc136f7faf } ts: 2015-05-29T14:03:34.504Z count: 17 new next call, error: { [MongoError: No more documents in tailed cursor] name: 'MongoError', message: 'No more documents in tailed cursor', tailable: true, awaitData: undefined } item: undefined ts: 2015-05-29T14:03:35.510Z count: 19