Cron and Redis

redis.md

Redis, Websockets and cron Discussion

Write your answers in the comment section below:

• What is Redis? Mention one use case of Redis.
• What type of database is Redis and where does it hold its data?
• What is Websocket and what is it used for?
• Explain 3 use cases for CRON jobs.
• What are the 3 types of design patterns in Nodejs?

Team members : Mohamad Karbejha - Feda - Hammam - Farah

1-What is Redis? Mention one use case of Redis.

Redis is an open-source, in-memory data store known for its speed and flexibility. It's not a traditional database, but rather a data structure server that uses RAM to store data, making it significantly faster than disk-based databases like MySQL or PostgreSQL. This speed advantage makes it ideal for a variety of use cases, with one of the most popular being caching.
Ex: Messaging and queues: Real-time chat applications, task queues, and event processing pipelines can all benefit from Redis's speed and reliability.

2-What type of database is Redis and where does it hold its data?
Redis actually isn't a traditional database in the typical sense. It's categorized as a NoSQL, in-memory data store

3-What is Websocket and what is it used for?
Websocket is a communication protocol that enables real-time, two-way communication between a client (like your web browser) and a server , like Stock tickers and news alerts: Updates are pushed instantly, keeping users informed in real-time.
For example :
https://kur.doviz.com/serbest-piyasa/amerikan-dolari

4- Explain 3 use cases for CRON jobs.
The cron command-line utility is a job scheduler on Unix-like operating systems. Users who set up and maintain software environments use cron to schedule jobs
1-Automated Backups
2-Scheduled Data Processing
3-System Maintenance Tasks

5-What are the 3 types of design patterns in Nodejs?
There are three types of design patterns: Creational - the creation of the object instances. Structural - the way the objects are designed. Behavioural - how objects interact with each other.

room 5 : mohamad, baraa,ahjmad, mahmoud

q1 -What is Redis? Mention one use case of Redis.

• Redis (which stands for Remote Dictionary Server) is an open-source, in-memory data structure store that can be used as a database, cache, and message broker. It supports various data structures such as strings, hashes, lists, sets, sorted sets, bitmaps, hyperloglogs, and geospatial indexes with radius queries.

• By using Redis as a caching layer, the web application can store frequently accessed data in memory, which is much faster than accessing data from a database.

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q2 - What type of database is Redis and where does it hold its data?

• Redis is a NoSQL database that stores data in memory. It is a key-value store, which means that it uses a simple key-value pair to store data.

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q3 - What is Websocket and what is it used for?

• WebSocket is a protocol that enables real-time, bidirectional communication between a web client (such as a web browser) and a server.

• It is a persistent connection that allows the client and server to send and receive data asynchronously without the need for constant polling or long-polling.

• WebSocket is used for a variety of applications that require real-time communication, such as:

  _**- 1 - Chat applications

  • 2- Real-time analytics
  • 3- Multiplayer games
  • 4- Collaborative editing
  • 5- Notifications**_

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q4 - Explain 3 use cases for CRON jobs.

• CRON jobs are a powerful tool for automating repetitive tasks in a Unix-like operating system.
• Here are three use cases for CRON jobs:
  **_- 1 - Database maintenance
  • 2 - Content updates
  • 3 - System monitoring_**

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q5 - What are the 3 types of design patterns in Nodejs?
**- 1 - Observer Pattern: **

• This pattern involves a subject (or observable) that maintains a list of its dependents (or observers) and notifies them automatically of any state changes.
• This pattern is commonly used in Node.js for event-driven programming.

** - 2 - Singleton Pattern: **

• This pattern ensures that a class has only one instance and provides a global point of access to that instance.
• This pattern is commonly used in Node.js for creating shared resources, such as a database connection or a logging utility.

- 3 - Module Pattern:

• This pattern involves creating a module by encapsulating related functions and variables within a single object.
• This pattern promotes code organization and reusability.

Team members: Muna Al Haj Eid, Hakimah Ismail, Gorgees Odisho, Raneem Hamrneh.

1. Redis is an open-source, in-memory data structure store that can be used as a database, cache, and message broker. It is known for its speed, scalability, and flexibility. Redis is an ideal choice for real-time analytics use cases such as social media analytics, ad targeting, personalization, and IoT.
2. Redis is NoSQL database because it does not use the traditional tabular structure of relational databases like SQL and it holds its data primarily in-memory.
3. WebSocket is a communication protocol that provides full-duplex communication channels over a single, long-lived connection between a client and a server. It enables real-time, two-way communication between web clients (such as browsers) and servers.
4. CRON jobs are automated tasks that run on a Unix-like operating system at specified intervals. Here are three use cases for CRON jobs:

• Automated backups: CRON jobs can be used to schedule automated backups of important files, databases, and directories. This ensures that data is backed up regularly and can be easily restored in case of data loss or corruption.
• Scheduled maintenance: CRON jobs can be used to schedule routine maintenance tasks such as software updates, security patches, and system scans. This helps keep the system up-to-date and secure.
• Automated reports: CRON jobs can be used to generate and send automated reports to stakeholders at regular intervals. For example, a CRON job can be used to generate a daily report of website traffic, sales, or other key metrics and email it to the relevant stakeholders.

5. The Factory pattern:
   Factory >>> decoupling object creation and implementation

a mechanism to enforce encapsulation
building a simple code profiler
builder >>> implementing url obj builder
revealing constructor>>>

• The Revealing Constructor pattern,
  function Person(name, age) {
  this.name = name;
  this.age = age;
  }

Person.prototype = (function() {
function sayName() {
console.log(this.name);
}

function sayAge() {
console.log(this.age);
}

return {
sayName: sayName,
sayAge: sayAge
};
})();

var person = new Person("John", 30);
person.sayName(); // Output: "John"
person.sayAge(); // Output: 30

• The Builder pattern.
• 

a way for you to structure your solution's code in a way that allows you to gain some kind of benefit, such as faster development speed, code reusability.

Jana AbuHaltam, Noor Alrai, Lujain Mansour, Mohamad Alchehabi

Q1
Redis offers a fast, in-memory data store to power live streaming use cases. Redis can be used to store metadata about users' profiles and viewing histories, authentication information/tokens for millions of users, and manifest files to enable CDNs to stream videos to millions of mobile and desktop users at a time.
it's an open source in-memory data store that can be used as a database, cache, or message broker. It's often used for caching web pages and reducing the load on servers. Redis also has some features that make it attractive for use as a database, such as support for transactions and publish/subscribe messaging.

Q2
Redis is a type of database that's commonly referred to as No SQL or non-relational, t holds its data primarily in memory, making it highly efficient for read and write operations. However, Redis also has the capability to persist data to disk, providing durability and backup options. This combination of in-memory storage and optional disk persistence enables Redis to deliver fast data access and manipulation while still ensuring data integrity and protection.

Q3
WebSocket is a technology that allows quick back-and-forth communication between a website (like a game or chat app) and a server. It's great for things that need constant, real-time updates, like chatting or online gaming. WebSocket makes this communication fast and efficient.

Q4.
1- Scheduled backups or data synchronization between different systems.
2-Regular system maintenance tasks like log rotation or database cleanup.
3-Periodic data aggregation or reporting tasks.
4-Automated scaling of resources based on time-specific requirements

Q5
1- Creational Patterns: These patterns provide ways to create objects while hiding the creation logic, creating a separation of concerns. Examples of creational patterns include the Singleton pattern, Factory pattern, and Constructor pattern.

2- Structural Patterns: Structural design patterns deal with how objects are composed to form larger structures. Examples in Node.js include the Module pattern, Decorator pattern, and Facade pattern.

3- Behavioral Patterns: Behavioral design patterns focus on how objects communicate and interact with each other. In Node.js, examples include the Observer pattern, Pub/Sub pattern, and Promises pattern.

Room 1: Yassin, Mohammad smadi, Musab, Belal

1. What is Redis? Mention one use case of Redis.

2. What type of database is Redis and where does it hold its data?

---

Redis is an open-source in-memory data store that works really well as a cache or message broker, It offers excellent performance, with the ability to quickly read and write data to memory.
An in-memory database is a type of database that stores data entirely in main memory (RAM) rather than on disk.

It can be used in cases where Real-time analytics are required, or in social media cases for ad personalisation.

3. What is WebSocket and what is it used for?

---

Websocket API is a realtime technology that's used to open a two-way interactive communication session between the user's browser and a server. it's like a constantly opened tunnel between two parties that can be used to pass data back and forth until one of the parties terminates the connection

4. Explain 3 use cases for CRON jobs.

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1. Data backup: we can set a scheduled task to backup specific data from a database every set time.
2. Server status: it can be used to check the status of the server constantly
3. Sending automated reports: Generating and sending reports on a scheduled basis.

5. What are the 3 types of design patterns in Nodejs?

---

1. Creational Design Pattern
2. Structural Design Pattern
3. Behavioral Design Pattern

Najwan Shawareb, Abdullah Alawad, Ramah Madi

Q1. Redis is an open-source (BSD licensed), in-memory data structure store used as a database, cache, message broker, and streaming engine.
Redis can be used to store metadata about users' profiles and viewing histories, authentication information/tokens for millions of users, and manifest files to enable CDNs to stream videos to millions of mobile and desktop users at a time.

Q2. Open-source (BSD licensed), in-memory data structure store.

Q3. WebSockets are a protocol for bi-directional, real-time communication between a client and a server over a single, long-lived connection. Unlike traditional HTTP requests, which are unidirectional and require a new connection for each request, WebSockets allow for continuous communication between the client and server.

Q4. Scheduled backups or data synchronization between different systems.
Regular system maintenance tasks like log rotation or database cleanup.
Periodic data aggregation or reporting tasks.

Q5. 1. the Factory pattern.
2. the Revealing Constructor pattern, the Builder pattern.
3. the Builder pattern.