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Approach to selecting a document

I am using Couchbase in a node app. Every time I insert a document, I am using a random UUID.
It inserts fine and I could retrieve data based on this id.
But in reality, I actually want to search by a key called url in the document. To be able to get or update or delete a document.
I could possibly add the url as the id I suppose but that is not what I see in any database concepts. Ids are not urls
or any unique names. They are typically random numbers or incremental numbers.
How could I approach this so that I can use a random UUID as id but be able to search by url?
Cos lets say the id was 56475-asdf-7856, I am not going to know this value to search for right.
Whereas if the id was https://www.example.com I know about this url and searching for it would give me what I want.
Is it a good idea making the url the id.
This is in a node app using Couchbase.
databaseRouter.put('/update/:id', (req, res) => {
updateDocument(req)
.then(({ document, error }) => {
if (error) {
res.status(404).send(error);
}
res.json(document);
})
.catch(error => res.status(500).send(error));
});
export const updateDocument = async (req) => {
try {
const result = await collection.get(req.params.id); // Feels like id should be the way to do this, but doesn't make sense cos I won't know the id beforehand.
document.url = req.body.url || document.url;
await collection.replace(req.params.id, document);
return { document };
} catch (error) {
return { error };
}
};

I think it's okay to use URLs as IDs, especially if that's the primary way you're going to lookup documents, and you don't need to change the URL later. Yes, often times IDs are numbers or UUIDs, but there is no reason you have to be restricted to this.
However, another approach you can take is to use a SQL query (SQL++, technically, since this is a JSON database).
Something like:
SELECT d.*
FROM mybucket.myscope.mydocuments d
WHERE d.url = 'http://example.com/foo/baz/bar'
You'll also need an index with that, something like:
CREATE INDEX ix_url ON mybucket.myscope.mydocuments (url)
I'd recommend checking out the docs for writing a SQL++ query (sometimes still known as "N1QL") with Node.js: https://docs.couchbase.com/nodejs-sdk/current/howtos/n1ql-queries-with-sdk.html
Here's the first example in the docs:
async function queryPlaceholders() {
const query = `
SELECT airportname, city FROM \`travel-sample\`.inventory.airport
WHERE city=$1
`;
const options = { parameters: ['San Jose'] }
try {
let result = await cluster.query(query, options)
console.log("Result:", result)
return result
} catch (error) {
console.error('Query failed: ', error)
}
}

Mongoose Update document

I am using Node.js and mongoose Module, I am looking for a way to count how many documents a user has and then if they have more then 0 documents it would edit their existing document and add the input so at the end it would have the previous text + the text that the user sent, so far this is how much I gotten.
const List = require('../Models/list.js')
List.countDocuments({}, function(err, count) {
if(count>0){
//edit document
}
else if(count=0){
const input = List.create({
User: User.name,
Songlist: args[0],
})
}
})
console.log('done')
here is how I think the code would look like
List.update(User.name) => update Songlist into List.Songlist + '|' + args[0]

I have never seen an update method like that. I am a nodejs developer. well, maybe there's a way like that.
Here's how I do to update a document
await Product.findByIdAndUpdate(id, //here where I have written "id" you have to write the id of the document you want to update.
{ //here in this object you have to put the variables of updated values
title: title,
description:description,
product_id:product_id,
category,
price,
});
there is also another method
await Product.findOneAndUpdate(name: 'asim', //let's suppose
{ //updated values
title:title,product: product
})
you can also read the documentation here https://mongoosejs.com/docs/tutorials/findoneandupdate.html

Javascript Axios get with conditional params

I am trying to get some data from an API. The problem is that the GET call could take none or some of the filters. I have tried but am not sure how/if I can create a URL with conditional filters.
actions: {
InstitutionSearch(value, id){
let fips = id['ParamValues'].find(o=>o.param==='fips')['value'];
let region = id['ParamValues'].find(o=>o.param==='region')['value'];
axios.get('https://educationdata.urban.org/api/v1/college-university/ipeds/directory/2019/',{
params:{
fips: ,
region: region,
offering_highest_level: 3
}
})
};
}
This is a vue application, with the code above running inside a vuex store. The id that is being passed in is an array of objects, that is taken from a search filter form. The problem that I have is that my query could include either fips or region or none.
My initial thought was the put fips and region equal to 0, but that does not work with my API. I am not opposed to building a query string inside conditionals, but there has to be an easier way. The following is an actual query for the data that I am working with https://educationdata.urban.org/api/v1/college-university/ipeds/directory/2019/?offering_highest_level=3.

With some amazing help, I figured out a simple solution. I created an empty object and then ran a conditional check on my parameters and only added them, if they met my qualifications. I then passed that object in as the parameters, and everything worked.
let fips = id['ParamValues'].find(o=>o.param==='fips')['value'];
let region = id['ParamValues'].find(o=>o.param==='region')['value'];
//code change
let params = {};
fips.length > 0 ? params['fips'] = fips.join(',') : null;
region != 0 ? params['region'] = region : null;
//code change
axios.get('https://educationdata.urban.org/api/v1/college-university/ipeds/directory/2019/',{
params
}).then(response=>{
console.log(response.data.results);
});

useEffect(() => {
axios
.get(
`http://stream-restaurant-menu-svc.herokuapp.com/item?category=${props.data}`
)
.then((response) => {
console.log("This is to show sub-categoary " + response.data);
setSubcate(response.data);
})
.catch((error) => {
console.log(error);
});
},[props]);

Cloud Firestore query works sometimes but not always

This has me really stumped. I have a method that searches for items in a Firestore database. It works when I call the method directly from a one-off test. It does not work when I call the method from another part of my app with the exact same input.
Here is the method that does the searching:
getProductsStartingWithCategory(textSoFar: string): Observable<Product[]> {
console.log('searching for ', textSoFar);
let endAt = textSoFar + '\uf8ff';
let filteredCollection: AngularFirestoreCollection<Product> =
this.afs.collection('products', ref =>
ref.orderBy('materialType').limit(30).startAt(textSoFar).endAt(endAt)
);
return filteredCollection.snapshotChanges().map(changes => {
return changes.map(a => {
console.log('matched one', a);
const data = a.payload.doc.data() as Product;
data.id = a.payload.doc.id;
return data;
});
});
}
And when I call the method directly from the first page in the app with a test button, it works. That method is as follows:
testTheThing() {
let text: string = 'Car';
this.productService.getProductsStartingWithCategory(text)
.subscribe(data => {
console.log('success', data);
});
}
Again, when I call this method I get results as expected (matching products in the database with materialType 'Carpet'.) Success!
But then, when I use the method from another page in the app, it returns no results. That page is a bit more complicated - essentially the method is being called when user input changes. Here are the relevant parts of the method:
productCategoryChanged(productPurchase: ProductPurchase) {
if (productPurchase.materialType) {
console.log('searching for products starting with "' + productPurchase.materialType + '"');
let unsubscribe = this.productService.getProductsStartingWithCategory(productPurchase.materialType).subscribe(products => {
products.forEach(product => {
// logic goes here...
});
});
// rest of method omitted
In both scenarios, I see the "searching for Car" in the console.log message. The search text is identical. I've tried numerous times with numerous different search text (all of which are in the database). The logging shows the method is being called with the right input, but for some reason I only find results when calling it from the "test" method. Why is that?
I've tried trimming the input. I do have another collection of 'products' hooked up to an observable, but I don't think that matters. I also have used this exact strategy for a "customer" search and that works fine. This "products" search is almost identical but it doesn't work.

LDAP JS with Node JS Finding users passing in patterns of string

I am currently using LDAP JS for Authentication in Angular JS app and everything works perfectly fine.
I am now building a new view and the requirement I have is this:
I have text box in which admin will write may be a few letters of a user id present in LDAP.
I want to show app matching ID present in LDAP on a typeahead/suggestions. I know how typeahead works so that's not an issue. The issue is how can I pass a rejex or pattern matching kind of a thing for uid in search() method.
My sample code is here:
function GetAllLDAPUser(dnFilter, res) {
client.search('uid=**WHAT-PATTERN-CAN-I-PASS-HERE**' + dnFilter, opts, function(err, result) {
result.on('searchEntry', function(entry) {
// I usually read entry.object or entry.raw here , that works
});
result.on('end', function(result) {
.......
});
}
}
}
So the question is what should I pass in place of
WHAT-PATTERN-CAN-I-PASS-HERE
Results :
Suppose I type an. The typeahead will show all user id starting with an like ana, anamon, analisa etc.

I have written the final solution and closed the issue on the project's repository
For pattern matching, we need to play with the 'filter' field in option object which we pass to the search method. So I ended up doing something like below:
var dnFilter = 'ou=People,o=Intra,dc=YOURCOMPANY,dc=com'; //depends on your LDAP settings.
var query;
var matchedUsers = [];
query.LDAPName = "dummy"; //some name which resides in LDAP
//You can even have one simple variable rather than having this query object.
opts = {
scope: 'sub',
filter: (shcDisplayName = '+ query.LDAPName + ')
'
};
//Do not use 'shcDisplayName' , this will be any variable stored in your LDAP object. You need get
//the structure of LDAP end point you are working on. For me, I had one variable 'shcDisplayName'
//on which I wanted to play so I am using this variable in my filter.
client.search(dnFilter, opts, function(err, result) {
result.on('searchEntry', function(entry) {
matchedUsers.push({
'Name': entry.object.shcDisplayName,
'Id': entry.object.uid
});
}
result.on('end', function(result) {
if (matchedUsers.length) { //if any match was found.
//send the json result back
res.json(matchedUsers);
//if you want to send json back, do not use res.send() otherwise you will end up getting
//circular reference error.
}
}
result.on('error', function(ex) {
//Handle errors here if any
});
});
}
}