MongoDb and Node.js: Listing server databases

 

Certain applications needs to identify the existing database instances in a certain database server. For this purpose, the database libraries provides mechanisms to identify metadata over its database instances, as its name, size on disk and amount of stored records/documents.

 

For identifying the existing databases in a mongodb server connection from node.js programming language you may run a code like this example below:

//npm install mongodb

 

const {MongoClient} = require('mongodb');

const uri = "mongodb://localhost:27017/";//$ mongo mongodb://<host>:<port>

const client = new MongoClient(uri);

 

client.connect().then(function(){

    //client.db().



    client.db().admin().listDatabases().then(function(databases){

        console.log("Databases:",databases);

    });

    

 

Just to not forget that before running the code it is necessary to install though npm the mongodb module.

Also it is important to highlight that here in the example the URI is pointing to a local database in its default port, but in another scenarios you may need to adjust that.

The complete code of this example is available here:

https://github.com/rafaelqg/code/blob/main/node_mongo_list_databases_async.js

A video class about this code you can see here:



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