i am creating relationship between two nodes that are created within the code but got error, can sombody tell me what should be arguments of fucnction below and what should be its format
node1.createRelationshipTo(node2, "some", {age:"20"}, function(err, relationship1)
{
if (err) {
console.err('Error saving new node to database:', err);
}
else {
relationship1.save(function (err,result)
{
if(err)
{
console.err('Error saving new node to database:', err);
}
});
}
});
No need to save the relationship after creating it. You can use relationship1 within the callback function.
node1.createRelationshipTo(node2, "some", {age:"20"}, function(err, relationship1) {
if (err) {
console.err('Error saving new node to database:', err);
} else {
// Do something with relationship1 here.
});
Related
Hi I have connection with db2 following way which works fine
require("ifxnjs").open(connectionString, function(err, con){
If(err){
console.log(err);
} else {
con.query(........){
}
}
});
I am trying to create a separate connection factory that can be called in any query. The code I have is
function confactory(){
db=require("ifxnjs).open(connectionString, function(err, conn){
if(err){} else {
console.log('connected');
}
})
return db
}
module.exports=confactory();
Than I access the connection in project
var db=require('./cofactory.js');
db.query('select * from emp', function(err, result){
if(err){}
else { cons
}
})
When I run the program I get error for
TypeError Can not read property 'query' of undefined
Please let me know how I can fix this issue. Thanks
I've taken this apart several different ways. The find happens after the remove, and the find never finds anything. If I comment out the this.accounts.remove... the find works. If I leave the remove line in there it doesn't. My understanding of cucumberjs, mongo client and node indicates that the find should work.
I've even tried moving the remove/find sequence into its own file, and it works there. It seems to be only when I'm running it in cucumber that the sequence fails. I suspect because of the way of cucumber loads the files, but I'm not sure.
Can someone help me figure out how to get this working?
World.js:
var db = new Db('FlashCards', new Server('localhost', 27017));
db.open(function(err, opened) {
if (err) {
console.log("error opening: ", err);
done(err);
}
db = opened;
});
var {
defineSupportCode
} = require('cucumber');
function CustomWorld() {
this.db = db;
this.accounts = db.collection('accounts');
hooks.js:
Before(function(result, done) {
//comment this out, and leave a done(), it works!!!!
this.accounts.remove(function(error, result){
if( error) {
console.log("Error cleaning the database: ", error);
done(error);
}
done();
})
});
user_steps.js:
Then('I will be registered', function(done) {
let world = this;
this.accounts.find({
username: world.user.username
}).toArray(
function(err, accounts) {
if (err) {
console.log("Error retrieveing data: ", err);
done(err);
}
console.log("Accounts found: ", accounts);
expect(accounts).to.be.ok;
expect(accounts.length).to.be.equal(1);
done();
});
});
Inovcation:
cucumber-js --compiler es6:babel-core/register
You are missing the item to be removed in the remove method. I am assuming the item to be removed is
this.accounts.remove(function(error, result){
You are missing one parameter to remove method. The parameter is query to remove. I am assuming, the remove query is {username: world.user.username}
var qry={username: world.user.username};
Please try with the following:
Before(function(result, done) { //comment this out, and leave a done(), it works!!!!
var qry={username: world.user.username};
this.accounts.remove(qry, function(error, result){
if( error) {
console.log("Error cleaning the database: ", error);
done(error);
}
done();
}) });
I'm very new to javascript/node.js and I'm having trouble with the following code. This is the handler for API an call. The 2nd code segment is just like the 1st, except there is an additional database lookup Merchant.findOne(...), and therefor the 'newTransaction.save()' function is nested one level deeper.
Both code segments return the 'output' variable value correctly. However, the second code segment does NOT also properly save the 'newTransaction' to the Mongo database.
I'm pretty sure the issue has to do with how/when the code returning from newTransaction.save(function (err, transaction){..} but I can't seem to get it straightened out.
I have been looking all over the internet trying to understand and fix this, with no success. Any help is appreciated...
Here is the older, simpler code that works as expected:
handler : function(request, reply) {
var output = {
"success": true,
"operations": [],
"epoch": Date.now()
};
Terminal.findById(request.payload.deviceNumber, function (err, terminal) {
if (err) {
return reply(Boom.internal('Error looking up terminal.', err));
}
if (terminal) {
ticket.quote("bitstamp", "USD", 1, function (err, exchangeRate) {
if (err) {
console.error(err);
return reply(Boom.internal('Error obtaining ticket quote.', err));
}
var newTransaction = new Transaction({
terminal: request.payload.deviceNumber,
merchant: terminal.merchant,
ccExchangeRate: exchangeRate.buy,
fiatAmtDue: request.payload.transactionValue,
ccAmtDue: ccAmtDueTruncated
});
newTransaction.save(function (err, transaction){
if (err) {
return reply(Boom.internal('Error creating new transaction.', err));
}
output.operations.push(
{
"control": "KeyPairGenControl",
"rand": cc.pseudoRandomBytes(32).toString('hex'),
"follow": {
"url": "/pos/v1/AddressAndEncKey",
"post": {
"transactionId": transaction.transactionId
}
}
}
);
return reply(output);
});
});
} else {
return reply(Boom.internal('Error looking up terminal.', err));
}
});
}
Here is the new code that does NOT save the newTransaction data into the Mongo DB.
handler : function(request, reply) {
var output = {
"success": true,
"operations": [],
"epoch": Date.now()
};
Terminal.findById(request.payload.deviceNumber, function (err, terminal) {
if (err) {
return reply(Boom.internal('Error looking up terminal.', err));
}
if (terminal) {
Merchant.findOne({merchantId: terminal.merchant}, function(err, merchant) {
if (err) {
console.log('Cannot find merchant');
return reply(output);
}
var processor = merchant.backendPaymentProcessor.name;
var localCurrency = merchant.localFiatCurrency;
//###################
ticket.quote(processor, localCurrency, 1, function (err, exchangeRate) {
if (err) {
console.error(err);
return reply(Boom.internal('Error obtaining ticket quote.', err));
}
var newTransaction = new Transaction({
terminal: request.payload.deviceNumber,
merchant: terminal.merchant,
ccExchangeRate: exchangeRate.buy,
fiatAmtDue: request.payload.transactionValue,
ccAmtDue: ccAmtDueTruncated
});
newTransaction.save(function (err, transaction){
if (err) {
return reply(Boom.internal('Error creating new transaction.', err));
}
output.operations.push(
{
"control": "KeyPairGenControl",
"rand": cc.pseudoRandomBytes(32).toString('hex'),
"follow": {
"url": "/pos/v1/AddressAndEncKey",
"post": {
"transactionId": transaction.transactionId
}
}
}
);
return reply(output);
});
//return reply(output);
});
//###################
});
} else {
return reply(Boom.internal('Error looking up terminal.', err));
}
});
}
I did a diff of your 2 version:
Check 1
ticket.quote
Callback are identical for both version
processor, localCurrency are different
Is exchangeRate pass into callback correct?
Check 2
newTransaction.save
newTransaction and callback for .save are setup identical
Check(console.log()) the values used in setting up new Transaction({...})
Check transaction object received by callback
Check/debug the code of Transaction.save().
I don't think the issue is with the code you posted. Both version reached return reply(output); inside newTransaction.save's callback. Very likely issue is inside Transaction class or Transaction.save() logic.
One scenario I can think of is when a transaction failed:
Transaction object is available (even for failed transaction)
Transaction Class / Transaction.save() does not write to db because transaction failed
Transaction.save() pass transaction object to callback, but NOT setting err, even when it should.
Mongoose having a feature to specify the collection name under the schema, or as the third argument when declaring the model. Otherwise it will use the pluralized version given by the name you map to the model.
Mongoose official doc having following statement:
Mongoose by default produces a collection name by passing the model name to the utils.toCollectionName method. This method pluralizes the name. Set this option if you need a different name for your collection.
schema-mapped:
new Schema({ <key>: <value>},
{ collection : '<collection name>' }); // collection name
model-mapped:
mongoose.model('<Model name>',
new Schema({ <key>: <value>}),
'<collection name>'); // collection name
You may also find same here
My app should update if tmx is newer, if older do nothing and if doesn't exist insert the document.
If the document is inserted, it works perfectly, else it doesn't update properly or says E11000 dup key.
trying to figure out if my callback are wrong or the logic. (I'm new to node.js+mongodb) MongoClient = require('mongodb').MongoClient,
assert = require('assert'),
url = 'mongodb://localhost:27017/pfc';
MongoClient.connect(url, function (err, db) {
run(db);
});
function run(db) {
fs.readFile('log.log', 'utf8', function (err, source) {
if (err) throw err;
var dataFile = JSON.parse(source);
dataFile.forEach(function (item) {
upsert(db, item, function (err, result) {
if (err) console.dir(err);
});
});
})
}
function upsert(db, doc, callback) {
db.collection('flags').findOne({vid: doc.vid}, function (err, item, result) {
if (item.vid != null) {
if (!(item.tmx instanceof Date)) {
item.tmx = new Date(item.tmx)
}
if(!(doc.tmx instanceof Date)){
doc.tmx = new Date(doc.tmx)
}
if (item.tmx < doc.tmx) {
console.dir("Date validation")
db.collection('flags').updateOne({vid: item.vid}, {
$set: {
"tmx": doc.tmx
}
},{upsert:true}, function (err, result) {
callback(err, result);
}
)
callback(err, result);
}
else{
console.dir("older")
callback(err, result);
}
}
else {
db.collection('flags').insertOne(doc, function(err, result) {
callback(err, result);
});
}
})}
Edit:
The documents from the 'log.log' file have this structure:
{
vid:2848
tmx: "2015-07-18T23:56:17.000Z"
}
{
vid: 2848
tmx: 2015-07-19T00:00:17.000Z
}
collection.find({vid: doc.vid},function(err,item){
if(!item) // didnt find in collection, items with vid: 2848
insert doc to collection
else if(item) //found an item with vid:2848
if (item.tmx < doc.tmx)//only update if doc.tmx is newer
update collection with the most recent document
with #Aaron Dufour help I got rid of the callback problem, thanks :)
but now the problem is when I have the collection already populated and go look for newest documents in log.log, it starts from the oldest document till the newest again :(
Your upsert is vulnerable to race conditions, and run calls it many times in parallel, so that is probably the issue. It is not clear exactly what doc will look like, so you might need slightly more complicated logic, but here's a version that uses Mongo's upsert to make things a bit safer:
function upsert(db, doc, callback) {
db.collection('flags').update({vid: doc.vid}, {$set: doc}, {upsert: true}, function(err) {
db.collection('flags').update({vid: doc.vid, tmx: {$lt: doc.tmx}}, {$set: tmx: doc.tmx}, function(err) {
callback();
});
});
}
Background:
I must create or update an document based on post request that I have zero control over. I'm calling the function updateOrCreate()
Question:
How can I properly find a document by an field called nuid without using _id in mongo/mongoose
example payload:
curl -H "Content-Type: application/json" -X POST -d '{"participant":{"nuid":"98ASDF988SDF89SDF89989SDF9898"}}' http://localhost:9000/api/things
thing.controller:
exports.updateOrCreate = function(req, res) {
//Thing.findByNuid() will not work but it will explain what i'm trying to accomplish
/**
Thing.findByNuid(req.body.participant.nuid, function (err, thing) {
if (err) { return handleError(res, err); }
if(!thing) {
Thing.create(req.body.participant, function(err, thing) {
if(err) { return handleError(res, err); }
});
}
var updated = _.merge(thing, req.body.participant);
updated.save(function (err) {
if (err) { return handleError(res, err); }
});
});
**/
//this block will fetch all the things that have nuids but that seems really heavy and awful practice
Thing.find({'nuid':req.body.participant.nuid}, function(err, thing){
console.log(thing);
});
// This block is here to communicate this will create a new thing as expected.
Thing.create(req.body.participant, function(err, thing) {
if(err) { return handleError(res, err); }
});
}
Schema
var ThingSchema = new Schema({
nuid: String
});
UPDATE:
var query = {"nuid": req.body.participant.nuid};
var update = {nuid: 'heyyy'};
Thing.findOneAndUpdate(
query,
update,
{upsert: true},
function(err, thing){
console.log(thing, "thing");
console.log(err, "err");
}
);
I would use findOneAndUpdate first and then based on the result do an insert. findOneAndUpdate use mongoDB findAndModify command.
You should also look at new & upsert options of it which would create a document if not found.