[TIL] 0309

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Today I Learnt 

 

 

 

 

 

왜 https는 맨날 하면서 고생하고 또 까먹는 걸까?

 

https://velog.io/@i01029407043/%ED%94%84% EB% A1% A0% ED% 8A% B8% EC%97%94% EB%93%9C-HTTPS-%EC%82% AC% EC% 9A% A9% ED%95%98% EA% B8% B0-AWS-EC2-Route53-Load-Balancer

HTTPS 사용하기 (AWS EC2, Route53, Load Balancer)

 

 

 

vercel에다가 한 번에 리액트  github repository랑 연동해서 자동 배포까지 되는데,

backend server가 https가 안돼 있어서 api call이 안 들어간다.

 

일단은 S3에 급하게 배포하기로 했다.

 

https://42place.innovationacademy.kr/archives/9784

AWS S3, CloudFront로 리액트(프론트) 배포하기

이거 아니면 그냥 임민영 튜터님 notion자료도 쉽게 설명되어 잇는 듯... 

 

 

Javascript :

 

null vs undefine :

 

null and undefined  

These are two types you need to know about, but won’t make as much sense until we get to variable declarations and functions. They make even less sense when you try and compare them without using ‘strict equals’.  

•       null is unlike the primitive types we have seen before.  It represents the lack of a value, as it does in most other languages.  

•       undefined is slightly different - it represents a value that has not been defined. 

•       null must be explicitly assigned or returned.   

•       undefined is what you get when you do not explicitly assign or return. 

 

We will cover these in more depth when looking at variables and functions, and their use will become pretty clear through repetition.  

 

 

The undefined value is a primitive value used when a variable has not been assigned a value.

The null value is a primitive value that represents the null, empty, or non-existent reference.

When you declare a variable through var and do not give it a value, it will have the value undefined. 

 

• null is an assigned value. It means nothing.
• undefined typically means a variable has been declared but not defined yet.

 

MUI

아무거나 막 가지고 와서 이것저것 해보다가 원래 되던 것도 안됐다 

깜작 놀랐네

 

https://exerror.com/you-are-running-create-react-app-4-0-3-which-is-behind-the-late st-release-5-0-0/

[Solved] You are running `create-react-app` 4.0.3, which is behind the latest release (5.0.0) - Exception Error

 

프런트를 하면서 , 항해 때 프런트분들이 정말 고생이 많았겠구나 매번 느낀다.

할게 한둘이 아니네..