can't find whether this has been asked before or not, so bear with me.
I'm just starting to use Neo4j with a nodejs backend and the neo4j-driver driver. I wonder if it's possible to create a node with several properties without enumerating each one in the second argument to the session.run method.
app.post("/signup", function(req, res) {
var user = req.body; //{userId: "johnsmith", email: "john#smith.com", ...}
session.run("CREATE (u:User {u}) RETURN u", user).then(function(response) {
/*do stuff with newly created user*/
}, function() {
//handle error
});
});
Currently, this yields the following error: {code: 'Neo.ClientError.Statement.ParameterMissing', message: 'Expected a parameter named u' }, and if I change the above to:
app.post("/signup", function(req, res) {
var user = req.body; //{userId: "johnsmith", email: "john#smith.com", ...}
session.run("CREATE (u:User {u}) RETURN u", {u: user}).then(function(response) {
/*do stuff with newly created user*/
}, function() {
//handle error
});
});
then the error reads: { code: 'Neo.ClientError.Statement.TypeError', message: 'Property values can only be of primitive types or arrays thereof' }.
This doesn't make much sense to me, given that the refcard clearly states you can create a node using a map, like so: CREATE (n {map}); so I must obviously be getting something wrong. I hope I don't have to enumerate all a user's properties like so:
session.run("CREATE (u:User {userId: {u.userId}, email: {u.email}, ...}) RETURN u", {u: user}).then(/*...*/)
Thanks in advance
Map could not be the value of the properties
You can set properties using a parameter - http://neo4j.com/docs/developer-manual/current/cypher/clauses/set/#set-set-all-properties-using-a-parameter
So you need to check the input parameter and transform its properties if necessary.
For example:
app.post("/signup", function(req, res) {
var params = {};
//{userId: "johnsmith", email: "john#smith.com", ...}
Object.keys(req.body).forEach( function(k) {
var value = req.body[k];
if (!isPrimitive(val)) value = JSON.stringify(value);
params[k] = value;
});
session.run("CREATE (u:User) SET u = {user} RETURN u", {user: params})
.then(function(response) {
// do stuff with newly created user
}, function() {
// handle error
});
});
Where isPrimitive an abstract function that checks whether a variable is a primitive.
Neo4j only supports storing specific kinds of data structures to a property. To quote from the Cypher Refcard:
Neo4j properties can be strings, numbers, booleans or arrays thereof.
And, to be more exact, in order for an array (or "collection") to be stored as a property value, all its elements must be of the same primitive type.
The answer from #stdob-- provides one possible simple workaround to this (but it stringifies all arrays, even ones that can be stored without conversion).
NOTE: The refacrd needs to be a bit more clear. Nested maps are supported, in general. For instance, you can freely pass in JSON data as Cypher query parameters. However, maps containing nested maps are NOT supported for storing as property values.
Related
I want to rename the factORLossTree into savefactORLossTree dynamically inside the function from below payload.
I am getting below data on payload after submitting the form.
{
"cluster":"Europe",
"factory":"Caivano",
"factoryId":"Caivano",
"factORLossTree":[
{
"skuid":"000000000067334539",
"skuDescription":"MAG 55ml Mini PistHazelnut 8MP x6x120 EB",
"levelLosses":[
{
"level1":"Line Scheduling Losses",
"variancePer":100
}
],
"isRowChecked":false
}
],
"submitType":"po"
}
Below is my code .
saveOrUpdateORData() {
const formData = Object.assign({}, this.orLosstreeForm.value);
if (formData.factORLossTree.length === 0) {
this.dialogService.openDialog('Data Not Available');
return false;
}
console.log(formData,"formdata");
return;
}
Expected Output
{
"cluster":"Europe",
"factory":"Caivano",
"factoryId":"Caivano",
"savefactORLossTree":[
{
"skuid":"000000000067334539",
"skuDescription":"MAG 55ml Mini PistHazelnut 8MP x6x120 EB",
"levelLosses":[
{
"level1":"Line Scheduling Losses",
"variancePer":100
}
],
"isRowChecked":false
}
],
"submitType":"po"
}
Can anyone please help me to do this.
Sure thing! Worth mentioning that this issue is purely JS and has nothing to do with your framework (e.g. - Angular)
To the point: let's assume that your payload is stored in a variable called payload
First - check if the property exists. Then - replace it:
const propertyName = 'put the property name here'
const newPropertyName = 'put the new property name here'
if (payload.hasOwnProperty(propertyName)) {
payload[newPropertyName] = payload[propertyName]
delete payload[propertyName]
}
Why this is working? Because we are creating another reference to the original data before deleting the property. At the end we end-up with one reference having the updated name
If (from some reason) you need to clone the data, follow this pattern instead:
if (payload.hasOwnProperty(propertyName)) {
const clone = JSON.parse(JSON.stringify(payload[propertyName]))
payload[newPropertyName] = clone
delete payload[propertyName]
}
I assume that your property always contains an object. If the type of the property is primitive (e.g. - number, string or boolean) you can just skip the cloning phase all together (primitives are copied by their values while only objects are handled by their reference)
I am trying to retrieve one particular value from within a two-levels deep object data structure. First off, though, I am saving into a variable within the function, like this:
getTargetId() {
if (this.authenticationService.isAuthenticated()) {
const userInfo = sessionStorage.getItem('currentUser');
console.log(userInfo);
}
}
From:
console.log(userInfo);
I get this back in the console:
{"token":"sometoken.value","data":{"_id":"8cd0362c0", "phone":"555-4343"...}
What I want to do is specifically pull out the "_id" value here.
I tried:
console.log(userInfo.data._id);
But then my IDE is showing me an error:
'Property '_id' does not exist on type 'string'.
How do I dig out "_id" in this case?
You are accessing it wrong
Try userInfo.data._id
In the log of your object you can see by the {} notation that data is another object, so after accessing data you can access its properties just as you would with any other object.
I also see that you are getting
'Property '_id' does not exist on type 'string'.
This could mean that you never parsed the information. To find out if this is the case this should be right:
Running->
console.log(userInfo);
Returns->
{"token":"sometoken.value","data":{"_id":"8cd0362c0", "phone":"555-4343"...}
Just after this code:
Running->
console.log(typeof userInfo);
Returns->
"string"
With your edits, I can see that this is the case.
Try:
userInfo = JSON.parse(sessionStorage.getItem('currentUser') );
console.log(userInfo.data._id);
The _id property is under the data key:
const response = {
"token":"sometoken.value",
"data": {
"_id":"8cd0362c0",
"phone":"555-4343"
}
};
console.log(response.data._id)
You can also use destructuring:
const { _id } = response.data;
console.log(_id)
or:
const { data: { _id }} = response;
console.log(_id);
So, as #jonsharpe pointed out, the key was to JSON.parse the string first. So this gets me the value I need for "_id":
getTargetId() {
if (this.authenticationService.isAuthenticated()) {
const userInfo = JSON.parse(sessionStorage.getItem('currentUser'));
console.log(userInfo.data._id);
}
}
Actually your string is returned as JSON string. So you have to parse it into object using JSON.parse() if you are using js or with $.parseJSON() if you are using Jquery. So your updated code now looks like this.
var user ='{"token":"sometoken.value","data":{"_id":"8cd0362c0", "phone":"555-4343"}}';
var k = JSON.parse(user);
alert(k.data._id);
And Fiddle is here.
Thank You
I'm running some project on MEAN.js and I've got a following problem. I want to make some user's profile calculation and the save it to database. But there's a problem with method in users model:
UserSchema.pre('save', function(next) {
if (this.password && this.password.length > 6) {
this.salt = new Buffer(crypto.randomBytes(16).toString('base64'), 'base64');
this.password = this.hashPassword(this.password);
}
next();
});
If I will send a password with my changes, it will change credentials, so user is unable to login next time. I want to delete password from user object before save, but I'm not able to do it (let's look at the comments in my code below):
exports.signin = function(req, res, next) {
passport.authenticate('local', function(err, user, info) {
if (err || !user) {
res.status(400).send(info);
} else {
/* Some calculations and user's object changes */
req.login(user, function(err) {
if(err) {
res.status(400).send(err);
} else {
console.log(delete user.password); // returns true
console.log(user.password); // still returns password :(
//user.save();
//res.json(user);
}
});
}
})(req, res, next);
};
What's wrong? Why the delete method returns true, but nothing happens? Thanks for your help :)
Just do:
user.password = undefined;
instead of:
delete user.password;
and the password property will not appear at the output.
there are certain rules for delete operator in javascript
if the property is an own non-configurable property in "strict mode" than it will return false.
for example
x = 42; // creates the property x on the global object
var y = 43; // creates the property y on the global object, and marks it as non-configurable
// x is a property of the global object and can be deleted
delete x; // returns true
// y is not configurable, so it cannot be deleted
delete y; // returns false
If the object inherits a property from a prototype, and doesn't have the property itself, the property can't be deleted by referencing the object. You can, however, delete it directly on the prototype.
for example
function Foo(){}
Foo.prototype.bar = 42;
var foo = new Foo();
// returns true, but with no effect,
// since bar is an inherited property
delete foo.bar;
// logs 42, property still inherited
console.log(foo.bar);
so, please cross check these point and for more information your can read this Link
Had a similar problem. This worked for me:
// create a new copy
let newUser= ({...user}._doc);
// delete the copy and use newUser that thereafter.
delete newUser.password;
Working with MONGOOSE?
If you're facing this issue when working with Mongoose (Mongo DB's upper layer) then you can use lean property on find method
Examples
Without lean (The keys won't be deleted)
const users = await User.find({ role: 'user' }) // no lean method
users.forEach((user) => {
delete user.password // doesn't delete the password
})
console.log(users)
/* [
{name:'John', password:'123'},
{name:'Susan', password:'456'}
]
*/
With lean (The keys get deleted)
const users = await User.find({ role: 'user' }).lean()
users.forEach((user) => {
delete user.password // deletes the password
})
console.log(users)
/* [
{name:'John'},
{name:'Susan'}
]
*/
Reason why lean works
Documents returned from queries with the lean option enabled are plain javascript objects, not Mongoose Documents. They have no save method, getters/setters, virtuals, or other Mongoose features.
Documents are kind of read-only, so delete doesn't work on them
Reference - https://stackoverflow.com/a/48137096/10824697
https://mongoosejs.com/docs/api.html#query_Query-lean
Method 2 without lean
If you want to use the mongoose provided method to remove some property while you are querying, you can remove with select method,
const users = await User.find({ role: 'user' }).select('-password')
console.log(users)
/* [
{name:'John'},
{name:'Susan'}
]
*/
The answer above from Majed A is the simplest solution that works for single objects properties, we can even make it for more easier by removing the ...user spreader. just delete the property from your object._doc sub-object. in your example it would have been:
user.save()
delete user._doc.password
res.status(201).json(user) // The password will not be shown in JSON but it has been saved.
Had a similar issue. The delete operator "was not working" when trying to delete a property from an object in a specific case. Fixed it using Lodash unset:
_.unset(user, "password");
https://lodash.com/docs/4.17.11#unset
Otherwise the delete operator does work. Just in case, delete operator docs here: https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Operators/delete
If password was defined with defineProperty, then configurable defaults to false if not set. In that case, then the property can't be deleted.
For me, node js still tells me the property was deleted (console.log(delete obj.prop)), but it wasn't deleting.
function test(settings) {
settings = {...{c: false, w:false}, ...settings}
let obj = {}
Object.defineProperty(obj, "prop", {
configurable: settings.c,
enumerable: settings.e ?? true,
writable: settings.w,
value: "foo"
});
console.log(
JSON.stringify(settings),
'\nset value to 1', (function() {obj.prop = 1})() || "",
'\nappended bar:', (function() {obj.prop += "bar"})() || "",
'\nobj:', JSON.stringify(obj),
'\ndelete:', delete obj['prop'],
'\nobj:', JSON.stringify(obj))
}
console.log('baseline: unchangeable, undeletable');
test()
console.log('unchangeable, deletable');
test({c: true})
console.log('changeable, undeletable');
test({w: true})
console.log('changeable, deletable');
test({c: true, w: true})
You may use this. It skips the unwanted key instead of deleting, it then returns an object.
let x = {1:'1', 2:2}
console.log('in', x)
function remove(Object, key){
let outputObject = {}
for (let inKey in Object){
if(key == inKey){
console.log(key , 'was deleted')
}else{
outputObject[inKey] = Object[inKey]
}
}
return outputObject
}
let out = remove(x, 1)
console.log('out', out)
The most likely, property which you want to delete has not owned the property for this object. In this case, the result of the operation will show true but nothing will be deleted.
This is maddening, how do I get a hold of a loopback model so I can programmatically work with it ? I have a Persisted model named "Notification". I can interact with it using the REST explorer. I want to be able to work with it within the server, i.e. Notification.find(...). I execute app.models() and can see it listed. I have done this:
var Notification = app.models.Notification;
and get a big fat "undefined". I have done this:
var Notification = loopback.Notification;
app.model(Notification);
var Notification = app.models.Notification;
and another big fat "undefined".
Please explain all I have to do to get a hold of a model I have defined using:
slc loopback:model
Thanks in advance
You can use ModelCtor.app.models.OtherModelName to access other models from you custom methods.
/** common/models/product.js **/
module.exports = function(Product) {
Product.createRandomName = function(cb) {
var Randomizer = Product.app.models.Randomizer;
Randomizer.createName(cb);
}
// this will not work as `Product.app` is not set yet
var Randomizer = Product.app.models.Randomizer;
}
/** common/models/randomizer.js **/
module.exports = function(Randomizer) {
Randomizer.createName = function(cb) {
process.nextTick(function() {
cb(null, 'random name');
});
};
}
/** server/model-config.js **/
{
"Product": {
"dataSource": "db"
},
"Randomizer": {
"dataSource": null
}
}
I know this post was here a long time ago. But since I got the same question recent days, here's what I figured out with the latest loopback api:
Loopback 2.19.0(the latest for 12th, July)
API, Get the Application object to which the Model is attached.: http://apidocs.strongloop.com/loopback/#model-getapp
You can get the application which your model was attached as following:
ModelX.js
module.exports = function(ModelX) {
//Example of disable the parent 'find' REST api, and creat a remote method called 'findA'
var isStatic = true;
ModelX.disableRemoteMethod('find', isStatic);
ModelX.findA = function (filter, cb) {
//Get the Application object which the model attached to, and we do what ever we want
ModelX.getApp(function(err, app){
if(err) throw err;
//App object returned in the callback
app.models.OtherModel.OtherMethod({}, function(){
if(err) throw err;
//Do whatever you what with the OtherModel.OtherMethod
//This give you the ability to access OtherModel within ModelX.
//...
});
});
}
//Expose the remote method with settings.
ModelX.remoteMethod(
'findA',
{
description: ["Remote method instaed of parent method from the PersistedModel",
"Can help you to impliment your own business logic"],
http:{path: '/finda', verb: 'get'},
accepts: {arg:'filter',
type:'object',
description: 'Filter defining fields, where, include, order, offset, and limit',
http:{source:'query'}},
returns: {type:'array', root:true}
}
);
};
Looks like I'm not doing well with the code block format here...
Also you should be careful about the timing when this 'getApp' get called, it matters because if you call this method very early when initializing the model, something like 'undefined' error will occur.
Scroll down to the bottom of this post to see a work around / possible solution.
This is probably easier just to explain in the source code with comments. The issue at hand is I cannot figure out how pseudo classes work together to perform the task I'm trying to do (explained in the code below).
The code is broken down into 3 files: lead.js, router.js, and db.js.
There are a decent amount of lines of code but most of it is comments.
[lead.js]
var bcrypt = require('bcrypt'),
validators = require('../lib/validators'),
utility = require('../lib/utility'),
document = {};
var Lead = module.exports = function (db) {
// Save a reference to the database.
this.db = db;
// Reference initial document.
// This is totally wrong, not sure how to 'send' a variable to the constructor of a class
// when I cannot add another param. Due to how I'm importing the db model, I won't know what
// the document is until I fill out the form. I've also tried 'document' instead of 'Lead.document'.
this.document = Lead.document;
// Setup the document if it exists.
// This also doesn't work.
// Basically I want to be able to set up a document variable outside of this module (line #100),
// Then pass it to this module after filling it up with values from a form.
// Then based on what's been filled in, it would fix up (trim, convert to lower case)
// some of the values automatically and default a few values that I'm not always going to pass.
if (!document) {
var salt = bcrypt.genSaltSync(10),
hash = bcrypt.hashSync(utility.generatePassword(), salt);
// Default values.
if (!document.meta.createdAt) { this.document.meta.createdAt = Date.now(); }
if (!document.login.password) { this.document.login.password = hash; }
if (!document.login.role) { this.document.login.role = 'User'; }
// Normalize a few values.
this.document.login.email = document.login.email.toLowerCase().trim();
this.document.contact.name.first = document.contact.name.first.trim();
this.document.contact.name.last = document.contact.name.last.trim();
this.document.contact.address.street = document.contact.address.street.trim();
this.document.contact.address.city = document.contact.address.city.trim();
this.document.contact.address.state = document.contact.address.state.trim();
this.document.contact.address.zip = document.contact.address.zip.trim();
this.document.contact.phone.home = document.contact.phone.home.trim();
}
// So in regards to the above code, the end result I'm looking for is...
// I want to append some properties to the this.document reference when the document is empty (when I'm updating it, I won't set the document),
// and on new documents it will append a few default values/normalize all the fields.
};
Lead.prototype.validate = function(fn) {
var errors = [];
// Some validation rules I cut out to make this shorter.
if (errors.length) return fn(errors);
fn();
};
Lead.prototype.save = function(fn) {
this.db.collection('leads', function(err, collection) {
if (err) { fn(new Error({message: err})); }
collection.insert(this.document, function(err, result) {
return fn(err, result);
});
});
};
---
[route.js file]
var db = require('../models/db');
app.post('/register', function(req, res) {
var data = req.body.lead || {};
// Fill the document.
var document = {
meta: {
host: req.headers.host,
referer: req.headers.referer,
createdIPAddress: req.connection.remoteAddress
},
login: {
email: data.email
},
contact: {
name: {
first: data.first,
last: data.last
},
address: {
street: data.street,
city: data.city,
state: data.state,
zip: data.zip
},
phone: {
home: data.phone
}
}
};
// Write the document.
db.lead.document = document;
db.lead.validate(function(err) {
if (err) {
req.session.error = err;
return res.redirect('back');
}
db.lead.save(function(err) {
res.redirect('/register/success');
});
});
});
---
[db.js]
var mongodb = require('mongodb'),
server = new mongodb.Server('localhost', 27017),
connection = new mongodb.Db('test', server);
connection.open(function(err, db) {});
module.exports = {
lead: new (require('./lead'))(connection)
};
When I run this, my validator always reports that the password is empty which makes sense. I'm sending the document initially to the class with an empty password (the password is randomly generated, not a form field) -- the problem is I have no idea what to do with the if (!document) ... code block to actually set the this.document properly.
I hope between the comments and code you can get an idea of what I'm trying to do. I've been stuck on this for a while.
EDIT
I changed the flow of it a bit to get a solution.
In the db.js, I exported the connection rather than instantiating the lead (and future models) directly.
In the router.js file, I require the db and lead file, then pass both the db connection and the document in the constructor of the Lead. Ex.
var lead = new Lead(db, document);
In the lead.js file, it becomes as simple as doing this.document = document (same as the db). When I submit a new lead, the values I don't send over from router.js get appended to the document (the created date, a random password, etc.) and everything is good.
Is this a decent way of handling this, or is there a better way to refactor this?
This is completely wrong way even if make this code work as you want. In this example you have singleton lead. By requesting /register url you want to set 'document' field to this singleton . (IMPORTANT) But requests work asynchronously. Absolutely no guarantee that you save the document, which has just validate. Because new request may overwrite it in lead object. You need to do this logic in request scope. One scope for one request. Not one for all.
You need to read up on object-oriented programming in Javascript.
The anonymous function you're defining near the top of your code is the constructor function, so with respect to the document property you want that is currently uninitialized, just type something like:
this.document = null;
Then some time later when you create a new object using this constructor, like so:
var myLead = new Lead(dbConnection);
You'll have the myLead.document property.
There are many other things wrong with your code, though. Why are you assuming that there is a global document variable with relevant data visible in your library when it's defined as {}? The code in that if statement at the end of your constructor should be run when the document property is set in your other file below, and should only expect this.document to exist.
You set var document = {} initially, and {} is not falsy. Better would be to set as a starting value document = null and then after checking for !document set document = {} before assigning whatever properties you need.