The Backend Engineering Show with Hussein Nasser

Database engines or storage engines or sometimes even called embedded databases is software library that a database management software uses to store data on disk and do CRUD (create update delete) Embedded means move everything in one software no network client server. In this video I want to go through the few popular database engines, explain the differences between them and finally I want to spin up a database and change its engine and show the different features on each engine Timecodes What is a database Engine 3:00 myISAM 9:43 Aria 16:30 InnoDB 19:00 XtraDB 25:30 LevelDB 27:40 RocksDB 34:00 SQLite 38:11 BerkelyDB 42:00 Demo! 47:11 Cards ACID 4:30 mysql/javascript 56:17 Resources https://youtu.be/V_C-T5S-w8g https://mariadb.com/kb/en/library/changes-improvements-in-mariadb-102/ https://mariadb.com/kb/en/library/why-does-mariadb-102-use-innodb-instead-of-xtradb/ https://github.com/facebook/rocksdb/wiki/Features-Not-in-LevelDB https://mariadb.com/kb/en/library/aria-storage-engine/ Best of MyISAM and InnoDB What is the performance impact of using CHAR vs VARCHAR on a fixed-size field? MySQL :: MySQL 8.0 Reference Manual :: 15.6.2.1 Clustered and Secondary Indexes Why Uber Engineering Switched from Postgres to MySQL | Uber Engineering Blog

Database Sharding Crash Course (with Postgres examples) Database sharding is process of segmenting the data into partitions that are spread on multiple database instances to speed up queries and scale the system. What is sharding? sharing key / partition key Consistent Hashing Horizontal partitioning vs Sharding Example Pros and cons What is Sharding? 1:30 Consistent Hashing 4:50 Horizontal partitioning vs Sharding 7:36 Example 8:45 Spin up Docker Postgres Shards 10:02 Write to the shard 17:25 Read from the Shard 39:20 Pros & Cons 51:10 Cards Postgres pgadmin Docker 8:54 Postgres Javascript 18:18 URL vs Query param 22:30 CORS 29:30 sql injection 42:40 Source Code https://github.com/hnasr/javascript_playground/tree/master/sharding Docker commands (including pgadmin) https://github.com/hnasr/javascript_playground/blob/master/sharding/shards/commands.txt Dockerfile & init.sql https://github.com/hnasr/javascript_playground/tree/master/sharding/shards Horizontal partitioning vs Sharding HP same database instance so you can still join sharding across instances (different server) Pros Extreme scale rdbms Optimal and Smaller index size Cons Transactions across shards problem Rollbacks Schema changes Complex client (aware of the shard) Joins Has to be something you know in the query Example URL shortener create table CREATE TABLE public.test1 ( id serial NOT NULL primary key, url text, url_id character(5) ) Spin up 3 instances p1 P2 P3 post get

Varnish is a reverse proxy web accelerator  Written in C designed to improve HTTP performance by using server side caching. In this video I’m going to go through how Varnish works, we will spin up a Varnish docker container and finally talk about the pros and cons of this tech. Agenda Classic HTTP Architecture How Varnish Works? HTTP Setup - Varnish HTTPS Setup - Varnish with Caddy as TLS Terminator. Varnish Pros & Cons Summary Pros Cache & prefetching documents Resolve DNS hostnames in documents Rewrite scripts to optimize code Load Balancing Backend Connection Pooling Varnish Modules (VMODS, e.g. rewrite headers) Edge side includes (personalized dynamic page) Cons Cache Invalidation Only works on unencrypted HTTP For HTTPS frontend, terminate TLS For HTTPS backend, no solution in Varnish open source Can’t cache POST requests (e.g. GraphQL queries) HTTP/2 backends won’t benefit docker commands docker run --name varnish -p 8080:80 varnish docker cp default.vcl varnish:/etc/varnish default.vcl vcl 4.0; backend default { .host = "husseinmac"; .port = "2015"; } timecodes Classic HTTP Architecture : 1:53 How Varnish Works 3:50 Demo HTTP 7:50 Demo HTTPS 18:23 Varnish Pros 28:43 Varnish Cons 39:26 Cards: Connection Pooling 2:15 https://www.youtube.com/watch?v=GTeCtIoV2Tw Layer 4 vs Layer 7 Load balancing 6:25 https://www.youtube.com/watch?v=aKMLgFVxZYk GET vs POST 6:48 https://www.youtube.com/watch?v=K8HJ6DN23zI Postgres NodeJS Chrome 8:23 https://www.youtube.com/watch?v=0JNq46eFuOM Redis 46:13 https://www.youtube.com/watch?v=sVCZo5B8ghE TLS Termination 49:35 https://www.youtube.com/watch?v=H0bkLsUe3no tags: varnish http accelerator, varnish pros and cons, varnish with https, varnish disadvantages Resources edge side includes https://www.fastly.com/blog/using-esi-part-1-simple-edge-side-include Cache invalidation varnish https://www.smashingmagazine.com/2014/04/cache-invalidation-strategies-with-varnish-cache/ ——

short is a major revision of the hyper text transfer protocol that improves the performance of the web. It uses a binary protocol and multiplexing. In this video I want to go through how HTTP/2 works, its pros and cons and show the performance difference between HTTP 1.1 and HTTP/2 Http/1 request has to wait for a response And if you used up your connection response you can send anything else. Source Code: https://github.com/hnasr/javascript_playground/tree/master/staticpage So hack ! 6 tcp connections Pros One connection Multipex Push ( have to enable) Hpack (compress) Cons Abuse push Proxies that dont support it might slow down Load balancer layer 7 (a layer 7 load balancer that doesnt support h2 will slow down when your web server supports it) Cards 1:25 HTTP crash course 12:30 TLS Time codes HTTP 1.1 2:15 HTTP/2 5:50 HTTP/2 With Push 8:25 HTTP/2 Pros 9:48 HTTP/2 Cons 14:10 Demo 17:15 +----------+--------+---------+---------+ | Protocol | Online | Fast 3G | Slow 3G | +----------+--------+---------+---------+ | HTTP 1.1 | 94 ms | 10 s | 36 s | +----------+--------+---------+---------+ | HTTP/2  | 171 ms | 2.7 s  | 10 s | +----------+--------+---------+---------+

Sorry about the free form audio and low quality thought I post something here its been while

Tor or (The Onion Router) is a free and open source project for allowing anonymous communication. In this video I want to discuss this technology and explain how it works. What can sniffers really see? Why Tor? Why don’t we just use a VPN? How Tor Works? More about Tor So if you are interested stay tuned. Cards: 6:00 TLS 10:53 symmetric key encryption TimeCodes: Normal Request 1:30 What sniffers see 4:30 Why Tor and not VPN? 6:00 How Tor Works 8:50 More tor info 21:00 Tor Directory Relay node Exit node Guard node

Apache Kafka is a distributed stream processing software developed by LinkedIn and written in Scala and Java. In this video I want to focus on the basics on Kafka, talk about how it works give finally spin up a kafka cluster and write a producer and a consumer. Kafka Components _ producer _consumer _topic _partition How Kafka works Example ( Ride sharing ) Spin Kafka cluster Write a producer Write a consumer Kafka Applications Pros and Cons

Tom Scott Full Video https://youtu.be/WVDQEoe6ZWY Tom Scott is a YouTuber with around 2M subscribers who discusses and specialized in computer security. I always enjoy his videos specially those on computerphile. He recently made a very interesting video titled This video is sponsor by —- We all probably know this is a reaction video to NordVPN Hack. He is really smart and not just because of his accent I wanted to make a video to elaborate on some of the statements that Tom made in his video and how that actually work. Cards 5:30 TLS https://www.youtube.com/watch?v=AlE5X1NlHgg 12:24 TLS Termination https://www.youtube.com/watch?v=H0bkLsUe3no Forged certificate https://slate.com/technology/2016/12/how-the-2011-hack-of-diginotar-changed-the-internets-infrastructure.html

RabbitMQ RabbitMQ is an open source distributed message queue written in Erlang and supports many communication protocols. It was trying to solve the spaghetti 🍝 mesh architecture where every client is communicating with other client in System by introducing an extra layer in the middle. (slide) In this video we will explain basic components of RabbitMQ Such as AMQP, channel, queue, publisher, consumer and some stuff, we will also learn how to spin up a RabbitMQ server and we will finally write some code to develop a publisher client that post messages to RabbitMQ. We will also write the consumer piece which will be the code that reads rabbitMQ. Finally I will talk about my personal thoughts on this tech. RabbitMQ Components(slide) *Publisher *Consumer *Connection *Channel *Queue Spin RabbitMQ server with Docker Write a Publisher client NodeJs Write a Consumer client Nodejs My Thoughts about this tech Summary timecodes components 2:00 spin up docker rabbit 8:30 Write a Publisher client NodeJs 11:00 Write a consumer client NodeJs 20:30 my thoughts 33:50 Source Code: https://github.com/hnasr/javascript_playground/tree/master/rabbitmq Example Schedule async job Exchange Queues Publisher Consumer AMQP Channel Connection HTTP AMQP Uses Channels and Queues Multiples channels into one connections docker run --name rabbitmq -p 5672:5672 -d rabbitmq docker run --name rabbitmq -p 5672:5672 -p 15672:15672 -d rabbitmq:3-management HTTP fetch("http://localhost:15672/api/vhosts”, {headers: {"Authorization" : `Basic ${btoa('guest:guest')}`}}).then(a=>a.json()).then(console.log) fetch("http://localhost:15672/api/channels", {headers: {"Authorization" : `Basic ${btoa('guest:guest')}`}}).then(a=>a.json()).then(console.log) fetch("http://localhost:15672/api/queues", {headers: {"Authorization" : `Basic ${btoa('guest:guest')}`}}).then(a=>a.json()).then(console.log) https://www.squaremobius.net/amqp.node/channel_api.html#channel_bindExchange https://www.rabbitmq.com/tutorials/tutorial-three-javascript.html

Redis is a noSQL key-value store, in memory database first that exploded in popularity in the past few years. In this video slash course, we will explain what Redis is, talk about the in-memory model, the optional durability, replication, clustering publish subscribe and the protocol and finally we will go through examples. During the video I will add time codes to each topic so you guys can jump to the topic that interests you the most.    Table of Content and TimeCodes  Redis as a NoSQL In Memory Key-Value store 3:49Optional Durability 10:00Transport Protocol 15:10Pub/Sub 18:24Replication and Clustering 20:40Examples 23:41Spin Docker 26:10Command CLI 28:50Set key 30:30  get key 31:00Set key with expiry 31:10exists key 32:00del 32:30  append key 32:50  publish subscribe 33:30   Commands  Docker run --name redis -p 6379:6379 redis docker exec -it rdb redis-cli    Cards 4:25 ACID!     Support me on PayPal  https://bit.ly/33ENps4  Become A Patron https://www.patreon.com/join/hnasr?