I want to convert ObjectID (Mongodb) to String in JavaScript.
When I get a Object form MongoDB. it like as a object has: timestamp, second, inc, machine.
I can't convert to string.
Try this:
objectId.str
See the doc.
ObjectId() has the following attribute and methods:
[...]
str - Returns the hexadecimal string representation of the object.
in the shell
ObjectId("507f191e810c19729de860ea").str
in js using the native driver for node
objectId.toHexString()
Here is a working example of converting the ObjectId in to a string
> a=db.dfgfdgdfg.findOne()
{ "_id" : ObjectId("518cbb1389da79d3a25453f9"), "d" : 1 }
> a['_id']
ObjectId("518cbb1389da79d3a25453f9")
> a['_id'].toString // This line shows you what the prototype does
function () {
return "ObjectId(" + tojson(this.str) + ")";
}
> a['_id'].str // Access the property directly
518cbb1389da79d3a25453f9
> a['_id'].toString()
ObjectId("518cbb1389da79d3a25453f9") // Shows the object syntax in string form
> ""+a['_id']
518cbb1389da79d3a25453f9 // Gives the hex string
Did try various other functions like toHexString() with no success.
You can use $toString aggregation introduced in mongodb version 4.0 which converts the ObjectId to string
db.collection.aggregate([
{ "$project": {
"_id": { "$toString": "$your_objectId_field" }
}}
])
Use toString:
var stringId = objectId.toString()
Works with the latest Node MongoDB Native driver (v3.0+):
http://mongodb.github.io/node-mongodb-native/3.0/
Acturally, you can try this:
> a['_id']
ObjectId("518cbb1389da79d3a25453f9")
> a['_id'] + ''
"518cbb1389da79d3a25453f9"
ObjectId object + String will convert to String object.
If someone use in Meteorjs, can try:
In server: ObjectId(507f191e810c19729de860ea)._str.
In template: {{ collectionItem._id._str }}.
Assuming the OP wants to get the hexadecimal string value of the ObjectId, using Mongo 2.2 or above, the valueOf() method returns the representation of the object as a hexadecimal string. This is also achieved with the str property.
The link on anubiskong's post gives all the details, the danger here is to use a technique which has changed from older versions e.g. toString().
In Javascript, String() make it easy
const id = String(ObjectID)
this works, You have mongodb object: ObjectId(507f191e810c19729de860ea),
to get string value of _id, you just say
ObjectId(507f191e810c19729de860ea).valueOf();
In Js do simply: _id.toString()
For example:
const myMongoDbObjId = ObjectID('someId');
const strId = myMongoDbObjId.toString();
console.log(typeof strId); // string
You can use string formatting.
const stringId = `${objectId}`;
toString() method gives you hex String which is kind of ascii code but in base 16 number system.
Converts the id into a 24 character hex string for printing
For example in this system:
"a" -> 61
"b" -> 62
"c" -> 63
So if you pass "abc..." to get objectId you will get "616263...".
As a result if you want to get readable string(char string) from objectId you have to convert it(hexCode to char).
To do this I wrote an utility function hexStringToCharString()
function hexStringToCharString(hexString) {
const hexCodeArray = [];
for (let i = 0; i < hexString.length - 1; i += 2) {
hexCodeArray.push(hexString.slice(i, i + 2));
}
const decimalCodeArray = hexCodeArray.map((hex) => parseInt(hex, 16));
return String.fromCharCode(...decimalCodeArray);
}
and there is usage of the function
import { ObjectId } from "mongodb";
const myId = "user-0000001"; // must contains 12 character for "mongodb": 4.3.0
const myObjectId = new ObjectId(myId); // create ObjectId from string
console.log(myObjectId.toString()); // hex string >> 757365722d30303030303031
console.log(myObjectId.toHexString()); // hex string >> 757365722d30303030303031
const convertedFromToHexString = hexStringToCharString(
myObjectId.toHexString(),
);
const convertedFromToString = hexStringToCharString(myObjectId.toString());
console.log(`convertedFromToHexString:`, convertedFromToHexString);
//convertedFromToHexString: user-0000001
console.log(`convertedFromToString:`, convertedFromToString);
//convertedFromToHexString: user-0000001
And there is also TypeScript version of hexStringToCharString() function
function hexStringToCharString(hexString: string): string {
const hexCodeArray: string[] = [];
for (let i = 0; i < hexString.length - 1; i += 2) {
hexCodeArray.push(hexString.slice(i, i + 2));
}
const decimalCodeArray: number[] = hexCodeArray.map((hex) =>
parseInt(hex, 16),
);
return String.fromCharCode(...decimalCodeArray);
}
Just use this : _id.$oid
And you get the ObjectId string. This come with the object.
Found this really funny but it worked for me:
db.my_collection.find({}).forEach((elm)=>{
let value = new String(elm.USERid);//gets the string version of the ObjectId which in turn changes the datatype to a string.
let result = value.split("(")[1].split(")")[0].replace(/^"(.*)"$/, '$1');//this removes the objectid completely and the quote
delete elm["USERid"]
elm.USERid = result
db.my_collection.save(elm)
})
On aggregation use $addFields
$addFields: {
convertedZipCode: { $toString: "$zipcode" }
}
Documentation of v4 (right now it's latest version) MongoDB NodeJS Driver says: Method toHexString() of ObjectId returns the ObjectId id as a 24 character hex string representation.
In Mongoose, you can use toString() method on ObjectId to get a 24-character hexadecimal string.
Mongoose documentation
Below three methods can be used to get the string version of id.
(Here newUser is an object containing the data to be stored in the mongodb document)
newUser.save((err, result) => {
if (err) console.log(err)
else {
console.log(result._id.toString()) //Output - 23f89k46546546453bf91
console.log(String(result._id)) //Output - 23f89k46546546453bf91
console.log(result._id+"") //Output - 23f89k46546546453bf91
}
});
Use this simple trick, your-object.$id
I am getting an array of mongo Ids, here is what I did.
jquery:
...
success: function (res) {
console.log('without json res',res);
//without json res {"success":true,"message":" Record updated.","content":[{"$id":"58f47254b06b24004338ffba"},{"$id":"58f47254b06b24004338ffbb"}],"dbResponse":"ok"}
var obj = $.parseJSON(res);
if(obj.content !==null){
$.each(obj.content, function(i,v){
console.log('Id==>', v.$id);
});
}
...
You could use String
String(a['_id'])
If you're using Mongoose along with MongoDB, it has a built-in method for getting the string value of the ObjectID. I used it successfully to do an if statement that used === to compare strings.
From the documentation:
Mongoose assigns each of your schemas an id virtual getter by default which returns the document's _id field cast to a string, or in the case of ObjectIds, its hexString. If you don't want an id getter added to your schema, you may disable it by passing this option at schema construction time.
Related
I am working on a project where I require to format incoming numbers in the following way:
###.###
However I noticed some results I didn't expect.
The following works in the sense that I don't get an error:
console.log(07);
// or in my case:
console.log(007);
Of course, it will not retain the '00' in the value itself, since that value is effectively 7.
The same goes for the following:
console.log(7.0);
// or in my case:
console.log(7.000);
JavaScript understands what I am doing, but in the end the actual value will be 7, which can be proven with the following:
const leadingValue = 007;
const trailingValue = 7.00;
console.log(leadingValue, trailingValue); // both are exactly 7
But what I find curious is the following: the moment I combine these two I get a syntax error:
// but not this:
console.log(007.000);
1) Can someone explain why this isn't working?
I'm trying to find a solution to store numbers/floats with the exact precision without using string.
2) Is there any way in JS/NodeJS or even TypeScript to do this without using strings?
What I currently want to do is to receive the input, scan for the format and store that as a separate property and then parse the incoming value since parseInt('007.000') does work. And when the user wants to get this value return it back to the user... in a string.. unfortunately.
1) 007.000 is a syntax error because 007 is an octal integer literal, to which you're then appending a floating point part. (Try console.log(010). This prints 8.)
2) Here's how you can achieve your formatting using Intl.NumberFormat...
var myformat = new Intl.NumberFormat('en-US', {
minimumIntegerDigits: 3,
minimumFractionDigits: 3
});
console.log(myformat.format(7)); // prints 007.000
Hi
You can use an aproach that uses string funtions .split .padStart and .padEnd
Search on MDN
https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/String/split
https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/String/padStart
https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/String/padEnd
Here you have an example:
const x = 12.1;
function formatNumber( unformatedNumber) {
const desiredDecimalPad = 3;
const desiredNonDecimalPad = 3;
const unformatedNumberString = unformatedNumber.toString();
const unformatedNumberArr = unformatedNumberString.split('.');
const decimalStartPadded = unformatedNumberArr[0].padStart(desiredDecimalPad, '0');
const nonDecimalEndPadded = unformatedNumberArr[1].padEnd(desiredNonDecimalPad, '0');
const formatedNumberString = decimalStartPadded + '.' + nonDecimalEndPadded;
return formatedNumberString;
}
console.log(formatNumber(x))
I am trying to convert a string i receive back from an API into a JSON object in Angular.
The issue is that the string is not normalized to be parsed into JSON easily.
This is the string im working with:
"{rootCause=EJBusinessException: This is a sample exception thrown for testing additional info field, description=This is a more detailed description about the incident., stackTrace=com.springboot.streams.infrastructure.web.heartbeat.HeartbeatService.testServiceNow(HeartbeatService.java:200)}"
When trying to do JSON.parse(myStr) it throws an error due to invalid string format.
Is there an easy way to convert the listed string into a more correct JSON format, getting rid of the '=' and replacing them with ':' instead.
There is more to it than just .replace(/['"]+/g, ''), as even with that the string is not ready to be turned into JSON yet.
Hoping someone more versed in Javascript knows a trick i dont.
You just need to manipulate the string before parsing it remove unecessary string that can cause error to the object like "{" and "}" and split it by "," example is in below.
var obj = {}, str = "{rootCause=EJBusinessException: This is a sample exception thrown for testing additional info field, description=This is a more detailed description about the incident., stackTrace=com.springboot.streams.infrastructure.web.heartbeat.HeartbeatService.testServiceNow(HeartbeatService.java:200)}"
str.split(",").forEach((st, i) => {
pair = st.split("=")
if(pair.length > 1) {
obj[pair[0].replace("{",'').replace("}", '').trim()] = pair[1]
} else {
obj[i] = pair
}
})
console.log(obj)
As commenters have posted, unless you control the API or at least have documentation that output will always follow a specific format, then you are limited in what you can do. With your current example, however you can trim off the extraneous bits to get the actual data... (remove braces, split on comma, split on equals) to get your key:value pairs... then build a javascript object from scratch with the data... if you need json string at that point can just JSON.stringify()
var initialString = "{rootCause=EJBusinessException: This is a sample exception thrown for testing additional info field, description=This is a more detailed description about the incident., stackTrace=com.springboot.streams.infrastructure.web.heartbeat.HeartbeatService.testServiceNow(HeartbeatService.java:200)}"
var trimmedString = initialString.substr(1, initialString.length - 2);
var pairArray = trimmedString.split(',');
var objArray = [];
pairArray.forEach(pair => {
var elementArray = pair.split('=');
var obj = {
key: elementArray[0].trim(),
value: elementArray[1].trim()
};
objArray.push(obj);
});
var returnObj = {};
objArray.forEach(element => {
returnObj[element.key] = element.value;
});
console.log(JSON.stringify(returnObj));
I'd like to check for a correct ObjectID to continue my code. I'am on NodeJS and I don't want to get the error:
Error: Argument passed in must be a single String of 12 bytes or a string of 24 hex characters
Actually I got those tests:
if (!user.id || !user.id.match("/^[0-9a-fA-f]{24}$") || !typeof(user.id) === 'string') {
console.log("user id is required !")
return callback("user id is required !")
}
For string of 24 hex characters I got this regex :
!user.id.match("/^[0-9a-fA-f]{24}$")
And I am searching for check if it is a string of 12 bytes :
!typeof(user.id) === 'string'
How should I add the verification for the 12 bytes?
Any idea please?
With NodeJS if you are using :
const objectID = require('mongodb').objectID
You could simply test your ObjectID like that :
ObjectID.isValid(yourobjectid)
It will return true if it is valid and false if it is not.
From what I see you can pass as an Id any string you want. You should
probably turn it into Hexadecimal string first (http://forums.devshed.com/javascript-development-115/convert-string-hex-674138.html)
function toHex(str) {
var hex = '';
for(var i=0;i<str.length;i++) {
hex += ''+str.charCodeAt(i).toString(16);
}
return hex;
}
and then create an ObjectId from the Hexadecimal string the way it is suggested from the mongoDB Documentation (https://docs.mongodb.com/manual/reference/method/ObjectId/)
Specify a Hexadecimal string
To generate a new ObjectId using ObjectId() with a unique hexadecimal string:
y = ObjectId("507f191e810c19729de860ea")
i'm new to mongoDB. I got my data as a string but i want to parse it to a decimal/ float.
I found made this code but it doesn't seem to work. This is my code, it replaces - for 00, * for "", and parses it a float. It gives no errors, but the parseFloat(doc).toFixed(2).
db.behuizingen.find().forEach(function(doc)
{
var price = doc.Prijs.replace('€', ''); // it may be vary for your other document
price = price.replace('-', '00');
price = price.replace('*', '');
doc.Prijs = Number(price);
parseFloat(doc).toFixed(2)
db.behuizingen.update({_id : doc._id} , doc;
})
Thanks in advance.
You did this wrong. Convert first and the Number() function of the shell has nothing to do with it. So replacing that line an continuing:
doc.Prijs = parseFloat(parseFloat(price).toFixed(2));
db.moederborden.update({_id : doc._id} , doc );
But also be beware. That usage of .update() where the second argument is there will "replace" the entire document with the contents of doc.
You may want to do this instead:
doc.Prijs = parseFloat(parseFloat(price).toFixed(2));
var update = { "$set": {} };
Object.keys(doc).each(function(key) {
update["$set"][key] = doc[key];
});
db.moederborden.update({_id : doc._id} , update );
Which uses the $set operator, so that any existing values that were not referenced in your doc object are not overwritten when writing to the database.
I had a similar issue where we had not had decimal serialisation enabled correctly and so I wanted to update documents that were already in our database to use the Decimal type instead of String. I used the following script:
db.MyCollection.find({ Price: { $type: "string" } }).forEach(function(doc) {
print('Updating price for ' + doc._id);
db.MyCollection.update(
{ _id: doc._id },
{ $set : { Price: NumberDecimal(doc.Price) } }
)
})
This only retrieves the documents that need updating by filtering on the field type, and then uses NumberDecimal to convert the string into a decimal.
I really like the format of the _ids generated by mongodb. Mostly because I can pull data like the date out of them client side. I'm planning to use another database but still want that type of _id for my document. How can I create these ids without using mongodb?
Thanks!
A very easy pseudo ObjectId generator in javascript:
const ObjectId = (m = Math, d = Date, h = 16, s = s => m.floor(s).toString(h)) =>
s(d.now() / 1000) + ' '.repeat(h).replace(/./g, () => s(m.random() * h))
Use the official MongoDB BSON lib in the client
I have a browser client that generates ObjectIds. I wanted to make sure that I employ the same ObjectId algorithm in the client as the one used in the server. MongoDB has js-bson which can be used to accomplish that.
If you are using javascript with node.
npm install --save bson
Using require statement
var ObjectID = require('bson').ObjectID;
var id = new ObjectID();
console.log(id.toString());
Using ES6 import statement
import { ObjectID } from 'bson';
const id = new ObjectID();
console.log(id.toString());
The library also lets you import using good old script tags but I have not tried this.
Object IDs are usually generated by the client, so any MongoDB driver would have code to generate them.
If you're looking for JavaScript, here's some code from the MongoDB Node.js driver:
https://github.com/mongodb/js-bson/blob/1.0-branch/lib/bson/objectid.js
And another, simpler solution:
https://github.com/justaprogrammer/ObjectId.js
Extending Rubin Stolk's and ChrisV's answer in a more readable syntax (KISS).
function objectId () {
return hex(Date.now() / 1000) +
' '.repeat(16).replace(/./g, () => hex(Math.random() * 16))
}
function hex (value) {
return Math.floor(value).toString(16)
}
export default objectId
ruben-stolk's answer is great, but deliberately opaque? Very slightly easier to pick apart is:
const ObjectId = (rnd = r16 => Math.floor(r16).toString(16)) =>
rnd(Date.now()/1000) + ' '.repeat(16).replace(/./g, () => rnd(Math.random()*16));
(actually in slightly fewer characters). Kudos though!
This is a simple function to generate a new objectId
newObjectId() {
const timestamp = Math.floor(new Date().getTime() / 1000).toString(16);
const objectId = timestamp + 'xxxxxxxxxxxxxxxx'.replace(/[x]/g, () => {
return Math.floor(Math.random() * 16).toString(16);
}).toLowerCase();
return objectId;
}
Here's a link! to a library to do that.
https://www.npmjs.com/package/mongo-object-reader
You can read and write hexadecimal strings.
const { createObjectID, readObjectID,isValidObjectID } = require('mongo-object-reader');
//Creates a new immutable `ObjectID` instance based on the current system time.
const ObjectID = createObjectID() //a valid 24 character `ObjectID` hex string.
//returns boolean
// input - a valid 24 character `ObjectID` hex string.
const isValid = isValidObjectID(ObjectID)
//returns an object with data
// input - a valid 24 character `ObjectID` hex string.
const objectData = readObjectID(ObjectID)
console.log(ObjectID) //ObjectID
console.log(isValid) // true
console.log(objectData) /*
{ ObjectID: '5e92d4be2ced3f58d92187f5',
timeStamp:
{ hex: '5e92d4be',
value: 1586681022,
createDate: 1970-01-19T08:44:41.022Z },
random: { hex: '2ced3f58d9', value: 192958912729 },
incrementValue: { hex: '2187f5', value: 2197493 } }
*/
There is a detailed specification here
http://www.mongodb.org/display/DOCS/Object+IDs
Which you can use to roll your own id strings