What is an API Gateway?

What's an API gateway? It is a server that exposes internal service APIs to external client devices, using a protocol like HTTP.
The gateway also uses design patterns like REST and GraphQL to expose APIs, which allow clients to get and update data through servers with databases.
In this video, we will talk about API gateways, their use cases, and how they work with CDNs and DNSes to ensure fast and reliable user request handling.
Some of their most common use cases are:
1. Authentication and Authorization
2. Request Transformation
3. Request Validation
4. Rate Limiting
5. Routing
6. Load Balancing
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00:00 What is an API Gateway?
01:02 Authentication on the Gateway
01:30 Request Transformation
02:07 Request Validation
02:43 Rate Limiting
03:09 Request Routing
04:20 Load Balancing
05:32 Architecture Overview
06:00 DNS
07:50 CDNs
09:30 Architecture Overview with AWS
10:31 War Story - Restart EVERY Week!
#SystemDesign #InterviewReady #Coding

[@jairajsahgal7101]

Thank you for such a good topic

[@olajohnson8101]

This is perfect timing on this topic. I’m working on a new API gateway for my company .

[@user-rr1dr7jm4y]

did you use a library if yes which one , any suggestions as i am working on api gateway for microservices . mern stack

[@NilakshMalpotra]

Thanks! Great vid

[@NeerajSharma-mz4es]

nice explanation

[@nehakhatri3921]

You are best teacher

[@aryankr]

kudos to your work on the topic.

[@gkcs]

Thank you!

[@everybot-it]

Thank you!

[@gkcs]

Thank you 😁

[@muhammedshafeeh9133]

Thanks gaurav

[@RicardoSilvaTripcall]

Great video as always, if it's possible, I would like to hear more about different techs or patterns that enable 3rd party services to communicate with each other without the need of API gateways.
API Gateways also acts as a Reverse Proxy, so your internal services are not exposed to the internet, how to do that without a proxy or a direct VPN link?

[@dpynsnyl]

to avoid SPOF in a single geographic location, we can also use something like Raft or Paxos to manage consensus and leader election.

[@SubhramRana]

Is api gateway is a persistent service? No. Then why is this required? Since this is stateless, deploying replica would serve the purpose

[@z.719]

Thanks 👍

[@gkcs]

Thank you!

[@shreyasgtrivikram8467]

Topic is Explained very nicely .
Would it be possible for you to provide the link for the free resource on CDN's on how they deliver live streaming . Would be really helpfull
Thank you 😇

[@ashishkumarmishra3570]

What is the algorithm working behind the load balancer forwarding requests to the POST service having the least load?

[@gkcs]

There are many: weighted round robin, least connections, etc...

[@cripz4203]

Our company uses AWS Chalice as the default tech stack now in almost all projects. 😅

[@mrrishiraj88]

Good day greetings

[@atulrai1713]

Why do we need to make a deployment on API Gateway in case of contract changes in any of the services? It is because you are also validating the incoming requests (validating request payload) on API Gateway?
Also, Does all the validation and authorization logic in API gateway goes inside the API Gateway Authorizer?

[@Prashantsingh896]

Right, lets say we are checking the incoming req against a predefined schema so any changes to that schema would need a new deployment. Otherwise incoming requests would be validated against the old schema.
Also not all validation/authorization logic goes in gateway, it can reside in service itself also.

[@r0075h3ll]

Is it the Controller that is referred to as API Gateway, or are these two completely different? If so, then how?

[@girishanker3796]

The controller is actually part of your service itself. Gateway is a server which routes the incoming client requests to the service ( which will hit the controller inside the service)

[@sachinbandil9245]

sir good evening as i am new to programming world and facing several challenges while solving the questions can you please help me to overcome come from this problem i want to learn these technologies

[@sadashivudubalabhadra4186]

Why do we need to add Authorization, validation, rate limit..etc in api gate level. We can add it in each microservice level correct?

[@RiteshYadav-rc1np]

yes you can do it but it will create unnecessary load on microservices why not to prevalidate all this things in api gateway so thats the crux

[@sanjeevkumarrai8440]

API gateways are used when client wants to call any of the endpoint right. but how does two microservice A and B will communicate with each other. Is it via gateway even when we use restTemplate to make API calls? Please answer this question

[@gkcs]

They communicate with each other directly using GRPC or some other protocol.
Have a look at my WhatsApp System Design video to get ideas around this.

[@shabeebck3057]

A this api gateway be netsjs ?

[@gopalsirotha]

Are you currently hiring for interviewready ??

[@gkcs]

Content writers, yes 😁

[@vaishalii_]

how come after two years of working you know so much,

[@gkcs]

It's 9 years of working 😛

[@vaishalii_]

hahaha okay maybe i rushed through your linkedIn@@gkcs

[@abhijeetsingh2933]

War story?

[@abhijeetsingh2933]

@@Elwacho1964 ? I didn't get it