DEV Community: Elson Jose

How to enable Authentication in mongodb ?

Elson Jose — Tue, 21 Feb 2023 12:42:03 +0000

Lets learn how to enable authentication in a local installation of mongodb.

Note: These steps are to be done on a linux OS

Start mongodb deamon
$ sudo systemctl start mongod
Connect to mongodb using shell
$ mongosh
Use admin database
$ use admin
Create new user. Replace USER_NAME & USER_PASSWORD with the values that you want.
$ db.createUser( ... { ... user: "USER_NAME", ... pwd: "USER_PASSWORD", ... roles: ["readWriteAnyDatabase"] ... } ... )
Exit shell
$ exit
Modify the configuration file to enable authentication
$ sudo nano /etc/mongod.conf
Uncomment security option and add authentication. The previous content will be
#secutiry
There are 2 spaces before the authorization: enabled line. Save using Ctrl+X, confirm using Y and Enter. After updating configuration it will look like this.
security: authorization: enabled
Restart mongod
$ sudo systemctl restart mongod
Verify the deamon is running and status is active
$ sudo systemctl status mongod
Connect to mongoDb using shell.
$ mongosh -u "USER_NAME" -p "USER_PASSWORD" --authenticationDatabase "admin"

If everything is correct it will connect to the default test database. To verify whether authentication is working use $ exit command and try to connect to mongoDb using
$ mongosh and list databases $ show dbs. It will return an error saying "MongoServerError: command listDatabases requires authentication".

How to use a different style while reusing a component ?

Elson Jose — Mon, 20 Feb 2023 05:20:47 +0000

In the CSS of the reusable component, create as many styles you want using '&'.

Note: Assuming that the className is component.

.component{
    // write the common styles here
}

.component {
    &-style1 {
        // write style 1 
    }
    &-style2 {
        // write style 2 
    }
}

Here the &-style1 and &-style2 are the additional styles that has be used while re-using the component. Now when you have to use &-style1, simple add the following CSS classname to the classname attribute of the component. For example

<div classname={"component component-style1"}>

This may need to passed as a prop to make it dynamic. Passing style={'-style1'} as a prop in the component and inside the component we can use the following.

<div classname={"component component"+props.style}>

That's it!

How to simplify importing multiple components in another component ?

Elson Jose — Sun, 19 Feb 2023 07:30:53 +0000

Suppose we have multiple components namely Component1, Component2 and Component3. Importing them in the main Component (usually the App Component) will look like this.

import Component1 from './path-to-component1'
import Component2 from './path-to-component2'
import Component3 from './path-to-component3'

This is repetitive. This can be solved by creating a new js file inside the components directory & exporting the components inside it.

export { default as Component1 } from './path-to-component1'
export { default as Component2 } from './path-to-component2'
export { default as Component3 } from './path-to-component3'

Now inside the main Component (usually the App Component) we can import them using the below one-liner.

import { Component1, Component2, Component3 } from './path-of-the-js-file-containing-export-statements'

How to serve angular app to all devices connected to your router ?

Elson Jose — Sat, 18 Feb 2023 09:44:30 +0000

Sometimes you might need to see how your site functions on another actual device. Follow these steps to learn how you can do that on angular.

Find the IP address assigned by your router to the device on which you are planning to serve the angular app. Use the following commands based on you operating systems.
$ ifconfig // for linux
$ ipconfig // for windows
In the results you can look for inet followed by the IP address assigned by your router to the device.
Then using that IP address use the following command to serve the angular application.
$ ng s --host=<YOUR_IP_ADDRESS_HERE> --port=<PORT_NUMBER>
You can replace YOUR_IP_ADDRESS_HERE with the result from step 1 and PORT_NUMBER with any available port number.
On another device connected to the same router, type the address https://<YOU_IP_ADDRESS_HERE>:<PORT_NUMBER>

Voilà....thats it.