¿ What is ?

ddmcdona06 — Sun, 11 Jun 2023 21:07:41 +0000

What exactly is Docker. Docker is a Platform As A Service, (PaaS), that uses virtualization to deliver software in packages called containers. Docker automates the deployment of these lightweight containers so that the software can work efficiently in multiple isolated environments.

Virtualization is the creation of a virtual computer hardware platform, storage, and network resources. Virtualization creates these virtual resources from hard drives, CPU's, and GPU's. When virtualizing you combine a network of resources into what is seemingly one object.

A Virtual Machine (VM) is software used for virtualization but must be built on top of hypervisor software. This allows VMs' to run a separate operating system from the host hardware. The advantages of this are you can install new software, change code to the operating system, or rollback to a previous configuration while maintaining the security of the host hardware and operating system.

A Container is an application completely isolated from other programs on a shared kernel. Containers are built from read-only images that usually run single processes or applications but can run multiple if needed. They are a guest operating system with virtual recourses who have no functional awareness of other processes running on the host operating system. The communication between the container and the device, as well as any other processes are handled by a container engine. One of the fundamental applications to Docker Daemon and its role in the Docker Engine.

Docker uses Daemon to create and manage containers. The advantage of these docker containers is their portability. They can run in multiple environments because of their lightweight in resource usage. They run consistently no matter the operating system you implement because each container packages its own dependencies.

Docker Containers Vs. Virtual Machines

Direct access to hardware
Easily update and delete instances of applications
Simplifies complex tasks such as a CI/CD Pipeline
Facilitate the use of microservices

Although these seem like two competing tools when deciding to virtualize your programs, they can be used together. The security of virtual machines and the efficiency of Docker containers allow you to take advantage of all the benefits of virtualization. When using VMs' to secure your applications and using containers to deploy code between machines you can utilize both of their strengths.

JS Blog - String Manipulation

ddmcdona06 — Sat, 29 Apr 2023 05:23:18 +0000

String Manipulation

Strings are vital in any programming language. String manipulation techniques help developers easily edit code. In JavaScript, strings are immutable and help to store text that includes characters, numbers, and Unicode. JavaScript includes many built-in functions for creating and manipulating strings in various ways. This blog will illustrate some of the functions that developers use as tools to write more efficient code. I will first illustrate string methods and then conclude with the plus operator.

String Methods:

.length() : returns the length of a string

ex. let name = "Darryl";
    let length = name.length => //6

.slice() : extracts a part of a string and returns it into a new string

ex. let places = "Los Angeles, Chicago, New York";
    let city = places.slice(13, 20) => // "Chicago"

.substring() : similar to slice but start and end values less than 0 are treated as 0

 ex. let places = "Los Angeles, Chicago, New York";
    let city = places.substring(-2, 11) => // "Los Angeles"

.substr() : similar to slice but the second parameter specifies the length of the extracted part

ex. let places = "Los Angeles, Chicago, New York";
    let city = places.substr(13, 7) => // "Chicago"

.concat() : joins two or more strings

ex. let text1 = "Be you";
    let text2 = "they'll adjust!";
    let confidence = text1.concat(" ", text2) => // "Be you they'll adjust!"

.toUpperCase() : converts all values in string to uppercase

ex. let text1 = "Be you";
    let text2 = text1.toUpperCase() => // "BE YOU"

.toLowerCase(): converts all values in strings to lowercase

ex. let text1 = "They'll Adjust!"; 
    let text2 = text1.toLowerCase() => // "they'll adjust!"

.trim() : removes white space from both sides of a string

ex. let text1 = "      Gator belts      ";
    let text2 = text1.trim() => // "Gator belts"

.trimStart() : removes white space from the start of a string

ex. let text1 = "      patty melts      ";
    let text2 = text1.trimStart() => // "patty melts    "

.trimEnd() : removes white space from the end of a string

ex. ex. let text1 = "      and Monte Carlos      ";
    let text2 = text1.trimEnd() => // "    and Monte Carlos"

.padStart()/.padEnd() : pads a string with another string

ex. let text = "10.00 - I'm broke";
    let padded = text.padStart(4,"x") => // "xxx10.00 I'm broke"

ex. let text = "Ballin! $100,";
    let padded = text.padEnd(4,"0") => // "Ballin! $100,000"

.charAt() : returns the character at a specified index (position) in a string

ex. let text = "Trekkie";
    let char = text.charAt(0) => // "T"

.charCodeAt() : returns the unicode of the character at a specified index in a string

ex. let text = "A Milli";
    let char = text.charCodeAt(0) => // 65

.replace() : replaces the first match in a string

ex. let text = "Ain't no thang like a chicken thigh";
    let newText = text.replace("thigh", "wang") => // "Ain't no thang like a chicken wang"

.replaceAll() : replaces all characters within a string

ex. let text = "I play cards. Cards can be challenging. I'm very competitive when I play cards!"
    text = text.replaceAll("Cards","Games");
    let text = text.replaceAll("cards","games") => // "I play games. Games can be challenging. I'm very competitive when I play games!"

.split() : Divides a string into an ordered list of two or more substrings and returns it

ex. let text = "Dallas";
let myCity = text.split("") => // [D, a, l, l, a, s]

The + Operator:
the plus operator concatenates values.

  ex. let string1 = "Ain't nobody dope as me,";
      let string2 = " I'm just so fresh, so clean!"
      let lyric = string1 + string2 => // "Ain't nobody dope as me, I'm just so fresh, so clean!"

DEV Community: ddmcdona06

******** ¿ What is ? ********

JS Blog - String Manipulation

¿ What is ?