🌼 BE TIL Day 20 0408

j00b33Β·2022λ…„ 4μ›” 11일
0

CodeCamp BE 02

λͺ©λ‘ 보기
19/30

⬇️ Main Note
https://docs.google.com/document/d/1c3LEm0IKmI6y--c3nGdjaxAmZISq7eHd3TfjwD-M1fc/edit


🌿 ManyToMany

Today, I'm trying to make productTags API. This one's in the format of manyToMany in database.
productTags will get the input in the form of array. => productTags: ["#new","#hi"]

  • tagsRepository should be made and linked with the product by using relations.

⬇️ Source code

async create({ createProductInput }) {
    const {
      productSaleslocation,
      productCategoryId,
      productTags,
      ...restProduct
    } = createProductInput; // dividing createProductInput into several variables so that things can be assigned separately. 

    const result = await this.productSaleslocationRepository.save({
      ...productSaleslocation,
    }); 

    // productTags : ["#wow","#chocolate","#yum"]
    // =-=-=-=-=-= productTags =-=-=-=-=-=
    const result2 = [];
    for (let i = 0; i < productTags.length; i++) {
      const tagName = productTags[i].replace('#', '');

      // ----------- tag overlap check -----------
      const prevTag = await this.productTagRepository.findOne({
        name: tagName,
      }); // Check whether the tag name already exists in database (= original tag)

      if (prevTag) {
        // If original tag exists
        result2.push(prevTag);
      } else {
        // If the original tag doesn't exist
        const newTag = await this.productTagRepository.save({ name: tagName });
        result2.push(newTag);
      }
    }

🌿 Login Process

Memory: Data are saved as variables, so when you shut down the computer, all data are removed.
Disk: Data are saved as text, which is saved inside the computer itself.

☁️ Stateful vs. Stateless

  • I chose stateless form for now.
    -> No need for session savings
  • The login status is saved in database
    -> SessionId = Login Token
    *** database is disk-based

🌿 Database Load-balancing


🐚 Vertical Partitioning
Data are saved column by column
ex) Things are saved in big categories: user data, payment data, etc

🐚 Horizontal Partitioning : Sharding
Normalized database(μ •κ·œν™”λœ DB: 1NF, 2NF...) are saved to reduce the data size.

❗️ Since database is disk-based, the speed of calling the data is slow.

☁️ Redis

So we're gonna use Redis, which is memory-based database.

  • Basically, Redis is put between backend server and database.
  • I'm using Redis for calling the user login info : token info.

☁️ JWT - Encryption

Or just save the login info in object-form and save the login info that's encrypted.
Encrypt <==> Decode
ex) γ„± - r, γ„΄ - s, γ„· - e … // β€œλ™λ™β€ : β€œehdehd”
--> This one's able to be hacked by the hackers.

So JWT is mostly used for encoding the info.

JWT : JSON Web Token --> Decoding website
Here in JWT, key is the string-type password
--> Using this key, only the one who knows the password is able to access for decoding.

⚠️ Warning
Since anyone could decode, important data shouldn't be saved; things like user's personal information.


🌿 Creating Sign up API


profile
μ½±γ…†l

0개의 λŒ“κΈ€