Concepts to be prepared for Any JavaScript Interview

HTML5

CSS3

JavaScript

OOJS

Functional JavaScript

ES6

LESS/SASS

Atomic CSS

Bootstrap/Material

MicroServices

Nodejs

Express

MongoDB / Any equivalent

Micro Frontends

React

Redux/Mobx

Angular

GraphQL

Docker

Devtools/Performance/Security Related questions

Data Structures and Algorithms

 

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VS Code Extensions

These are the best extensions that i configured to enable best features and rich UX as shown below..

Some of the VS Code features here..

Rename All Occurrences

Refactoring is a necessary aspect of writing and maintaining clean code, but it can be quite the headache — especially when you’re refactoring a large module or an otherwise huge chunk of code. So instead of hunting through dozens of files just to rename a variable or method, let VS Code do it for you.

If you select a variable/method and hit F2, you can edit the name and it will change every instance of that variable’s name throughout the entire current working project.

If you only want to change within the current file, use the Command + F2 (on Mac) or Ctrl + F2 (on Windows) keyboard shortcut and VS Code will spawn a cursor at every instance throughout the current file.

Go to Definition

When you’re programming or scripting, often times you’ll run into a variable or method that you don’t recognize. So what do you do? You could spend several minutes searching for the right file, or you could press Command (on Mac) or Ctrl (on Windows) key and click the variable/method with your mouse. VS Code will take you to it’s definition right away.

Or you could just hover your cursor over the variable/method along with pressing the Command (on Mac) or Ctrl (on Windows) key, it will shows you the definition right in line where your cursor is.

Edit Multiple Lines at Once

If you ever need to insert or delete multiple instances of text throughout a document, all you have to do is create multiple cursors. You can do this by holding down Option (on Mac) or Alt (on Windows) and clicking anywhere in the text. Every click creates a new cursor.

This is particularly useful for things like HTML, where you might want to add many instances of the same class or change the format of several hyperlinks.

Few More here
https://medium.com/@i_AnkurBiswas/pro-tips-for-visual-studio-code-to-be-productive-in-2018-d5252e914561
https://dev.to/seankilleen/vscode-tip-watching-files-1hkk

Shortcuts

mac: https://code.visualstudio.com/shortcuts/keyboard-shortcuts-macos.pdf
windows: https://code.visualstudio.com/shortcuts/keyboard-shortcuts-windows.pdf

Most Useful Google Chrome Browser chrome:// Commands

chrome://flags

chrome://inspect/#devices

chrome://dns

chrome://memory

chrome://net-internals

chrome://quota-internals

chrome://sync-internals

chrome://sessions

chrome://settings

chrome://downloads

chrome://extensions

chrome://bookmarks

chrome://history

chrome://version/

chrome://about/

 

Finally, to view all the available chrome:// commands, type chrome://about/ in your chrome browser URL as shown below.

GraphDB

MySQL (RDBMS) = Organizes in Tables
MongoDB (Documents) = Organizes in Documents
Cassandra (Columnar) = Organizes in Column family
Neo4j (Graph) = Organizes in Tree resembling, convenient for traversal

Each or different approach and trade-off of CAP theorem.

Neo4j as Graph Database

 

Docker

its a utility – package of processes for distributed network

allows us to provision isolated process for scaling applications

packaged as a package micro controller.

eg: network deployments

package and deployment applications – first use case.

http://www.docker.com/getting-started

download and install from docker.com

https://www.docker.com/get-docker
once it is installed, type docker in terminal and hit enter. it will show docker related commands.

 

Usage: docker COMMAND

A self-sufficient runtime for containers

Options:
–config string Location of client config files (default
“/Users/svaka1/.docker”)
-D, –debug Enable debug mode
-H, –host list Daemon socket(s) to connect to
-l, –log-level string Set the logging level
(“debug”|”info”|”warn”|”error”|”fatal”)
(default “info”)
–tls Use TLS; implied by –tlsverify
–tlscacert string Trust certs signed only by this CA (default
“/Users/svaka1/.docker/ca.pem”)
–tlscert string Path to TLS certificate file (default
“/Users/svaka1/.docker/cert.pem”)
–tlskey string Path to TLS key file (default
“/Users/svaka1/.docker/key.pem”)
–tlsverify Use TLS and verify the remote
-v, –version Print version information and quit

Management Commands:
checkpoint Manage checkpoints
config Manage Docker configs
container Manage containers
image Manage images
network Manage networks
node Manage Swarm nodes
plugin Manage plugins
secret Manage Docker secrets
service Manage services
stack Manage Docker stacks
swarm Manage Swarm
system Manage Docker
trust Manage trust on Docker images (experimental)
volume Manage volumes

Commands:
attach Attach local standard input, output, and error streams to a running container
build Build an image from a Dockerfile
commit Create a new image from a container’s changes
cp Copy files/folders between a container and the local filesystem
create Create a new container
deploy Deploy a new stack or update an existing stack
diff Inspect changes to files or directories on a container’s filesystem
events Get real time events from the server
exec Run a command in a running container
export Export a container’s filesystem as a tar archive
history Show the history of an image
images List images
import Import the contents from a tarball to create a filesystem image
info Display system-wide information
inspect Return low-level information on Docker objects
kill Kill one or more running containers
load Load an image from a tar archive or STDIN
login Log in to a Docker registry
logout Log out from a Docker registry
logs Fetch the logs of a container
pause Pause all processes within one or more containers
port List port mappings or a specific mapping for the container
ps List containers
pull Pull an image or a repository from a registry
push Push an image or a repository to a registry
rename Rename a container
restart Restart one or more containers
rm Remove one or more containers
rmi Remove one or more images
run Run a command in a new container
save Save one or more images to a tar archive (streamed to STDOUT by default)
search Search the Docker Hub for images
start Start one or more stopped containers
stats Display a live stream of container(s) resource usage statistics
stop Stop one or more running containers
tag Create a tag TARGET_IMAGE that refers to SOURCE_IMAGE
top Display the running processes of a container
unpause Unpause all processes within one or more containers
update Update configuration of one or more containers
version Show the Docker version information
wait Block until one or more containers stop, then print their exit codes

How to install mongo in docker??

docker pull mongo

Set port number and run mongo from docker??

docker run –name mongodb -p 37017:27017 -d mongo

How to start mongodb in docker?

docker start mongodb

How to view the collections and data in docker mongodb?

install Robo 3T from https://robomongo.org/download

Open it and click on create button and do the following

Then click on save. Later click on connect to view the database in Robo 3T.