Dotenv-expand: Variable Expansion for Dotenv

dotenv-expand

Dotenv-expand adds variable expansion on top of dotenv. If you find yourself needing to expand environment variables already existing on your machine, then dotenv-expand is your tool.   

Install

# Install locally (recommended)
npm install dotenv-expand --save

Or installing with yarn? yarn add dotenv-expand

Usage

Create a .env file in the root of your project:

PASSWORD="s1mpl3"
DB_PASS=$PASSWORD

As early as possible in your application, import and configure dotenv and then expand dotenv:

var dotenv = require('dotenv')
var dotenvExpand = require('dotenv-expand')

var myEnv = dotenv.config()
dotenvExpand.expand(myEnv)

console.log(process.env)

That's it. process.env now has the expanded keys and values you defined in your .env file.

Preload

You can use the --require (-r) command line option to preload dotenv & dotenv- . By doing this, you do not need to require and load dotenv or dotenv-expand in your application code. This is the preferred approach when using import instead of require.

$ node -r dotenv-expand/config your_script.js

The configuration options below are supported as command line arguments in the format dotenv_config_<option>=value

$ node -r dotenv-expand/config your_script.js dotenv_config_path=/custom/path/to/your/env/vars

Additionally, you can use environment variables to set configuration options. Command line arguments will precede these.

$ DOTENV_CONFIG_<OPTION>=value node -r dotenv-expand/config your_script.js

$ DOTENV_CONFIG_ENCODING=latin1 node -r dotenv-expand/config your_script.js dotenv_config_path=/custom/path/to/.env

Examples

See tests/.env for simple and complex examples of variable expansion in your .env file.

Documentation

DotenvExpand exposes one function:

• expand

Expand

expand will expand your environment variables.

const dotenv = {
  parsed: {
    BASIC: 'basic',
    BASIC_EXPAND: '${BASIC}',
    BASIC_EXPAND_SIMPLE: '$BASIC'
  }
}

const obj = dotenvExpand.expand(dotenv)

console.log(obj)

Options

ignoreProcessEnv

Default: false

Turn off writing to process.env.

const dotenv = {
  ignoreProcessEnv: true,
  parsed: {
    SHOULD_NOT_EXIST: 'testing'
  }
}
const obj = dotenvExpand.expand(dotenv).parsed

console.log(obj.SHOULD_NOT_EXIST) // testing
console.log(process.env.SHOULD_NOT_EXIST) // undefined

FAQ

What rules does the expansion engine follow?

The expansion engine roughly has the following rules:

• $KEY will expand any env with the name KEY
• ${KEY} will expand any env with the name KEY
• \$KEY will escape the $KEY rather than expand
• ${KEY:-default} will first attempt to expand any env with the name KEY. If not one, then it will return default

You can see a full list of examples here.

Contributing Guide

See CONTRIBUTING.md

CHANGELOG

See CHANGELOG.md

Who's using dotenv-expand?

These npm modules depend on it.

Download Details:

Author: Motdotla
Source Code: https://github.com/motdotla/dotenv-expand 
License: BSD-2-Clause license

#javascript #variables #dotenv 

What is GEEK

Buddha Community

Dotenv-expand: Variable Expansion for Dotenv

dotenv-expand

Dotenv-expand adds variable expansion on top of dotenv. If you find yourself needing to expand environment variables already existing on your machine, then dotenv-expand is your tool.   

Install

# Install locally (recommended)
npm install dotenv-expand --save

Or installing with yarn? yarn add dotenv-expand

Usage

Create a .env file in the root of your project:

PASSWORD="s1mpl3"
DB_PASS=$PASSWORD

As early as possible in your application, import and configure dotenv and then expand dotenv:

var dotenv = require('dotenv')
var dotenvExpand = require('dotenv-expand')

var myEnv = dotenv.config()
dotenvExpand.expand(myEnv)

console.log(process.env)

That's it. process.env now has the expanded keys and values you defined in your .env file.

Preload

You can use the --require (-r) command line option to preload dotenv & dotenv- . By doing this, you do not need to require and load dotenv or dotenv-expand in your application code. This is the preferred approach when using import instead of require.

$ node -r dotenv-expand/config your_script.js

The configuration options below are supported as command line arguments in the format dotenv_config_<option>=value

$ node -r dotenv-expand/config your_script.js dotenv_config_path=/custom/path/to/your/env/vars

Additionally, you can use environment variables to set configuration options. Command line arguments will precede these.

$ DOTENV_CONFIG_<OPTION>=value node -r dotenv-expand/config your_script.js

$ DOTENV_CONFIG_ENCODING=latin1 node -r dotenv-expand/config your_script.js dotenv_config_path=/custom/path/to/.env

Examples

See tests/.env for simple and complex examples of variable expansion in your .env file.

Documentation

DotenvExpand exposes one function:

• expand

Expand

expand will expand your environment variables.

const dotenv = {
  parsed: {
    BASIC: 'basic',
    BASIC_EXPAND: '${BASIC}',
    BASIC_EXPAND_SIMPLE: '$BASIC'
  }
}

const obj = dotenvExpand.expand(dotenv)

console.log(obj)

Options

ignoreProcessEnv

Default: false

Turn off writing to process.env.

const dotenv = {
  ignoreProcessEnv: true,
  parsed: {
    SHOULD_NOT_EXIST: 'testing'
  }
}
const obj = dotenvExpand.expand(dotenv).parsed

console.log(obj.SHOULD_NOT_EXIST) // testing
console.log(process.env.SHOULD_NOT_EXIST) // undefined

FAQ

What rules does the expansion engine follow?

The expansion engine roughly has the following rules:

• $KEY will expand any env with the name KEY
• ${KEY} will expand any env with the name KEY
• \$KEY will escape the $KEY rather than expand
• ${KEY:-default} will first attempt to expand any env with the name KEY. If not one, then it will return default

You can see a full list of examples here.

Contributing Guide

See CONTRIBUTING.md

CHANGELOG

See CHANGELOG.md

Who's using dotenv-expand?

These npm modules depend on it.

Download Details:

Author: Motdotla
Source Code: https://github.com/motdotla/dotenv-expand 
License: BSD-2-Clause license

#javascript #variables #dotenv 

Reference Variable in Java

Before We Started with the Reference variable we should know about the following facts.

**1. **When we create an object(instance) of class then space is reserved in heap memory. Let’s understand with the help of an example.

Demo D1 = new Demo();

Now, The space in the heap Memory is created but the question is how to access that space?.

Then, We create a Pointing element or simply called Reference variable which simply points out the Object(the created space in a Heap Memory).

**Understanding Reference variable **

1. Reference variable is used to point object/values.

**2. **Classes, interfaces, arrays, enumerations, and, annotations are reference types in Java. Reference variables hold the objects/values of reference types in Java.

3. Reference variable can also store null value. By default, if no object is passed to a reference variable then it will store a null value.

**4. **You can access object members using a reference variable using **dot **syntax.

.<instance variable_name / method_name>

#java #reference variable in java #variables in java #reference variables #refer #variable's

Scope of a Variable In Java [With Coding Example]

Introduction

Programmers define the scope of a Variable in Java that tells the compiler about the region from where a variable is accessible or visible. The scope of a variable in Java is static by nature. It means we have to declare it at compile time only. In this article, you will learn about the scope of a Java variable along with its types

What is the Scope of a Variable in Java?

Salient Points About the Scope of a Variable in Java

Conclusion

#full stack development #java variable #scope of a variable in java #variable #scope of a variable #scope

Basic Variable Types in Python

This written lesson is part of Banana Chip Tech’s Python Crash Course. For video lectures, programming homework assignments, and other content please visit our website.

Variables are ways that we can store information for use later on in a program. For this reason, they are incredibly helpful when programming. The way that I like to think about variables are like jars where we can stuff information in and then take information out later. A good real world example of what a variable does can be found in food containers. The food container itself would be the variable and the food that it holds would be the data that a variable would hold. For instance, we can store some peanut butter in our peanut butter jar. We can then take our peanut butter out of the jar and use it when we want to make our peanut butter and jelly sandwich. Similarly, we can have a pizza box which is holding our pizza. Later on when we are hungry, we can take out a piece of pizza and eat it. Both the peanut butter jar and pizza box act as storage containers, but _what _they store is different. All python variables store information, but the type of information that they store differs.

While python doesn’t force you to document what specific type of variable you’re going to be using, knowing the type of variable used can be critical for the success of your program. I like to classify python variables into two distinct types: basic variable types and data structure variable types. In this tutorial, we talk about the different basic variable types.

Basic variable types contain only a single piece of information. These basic variable types are like our peanut butter jar that only stores peanut butter. We can’t store cheese or bread in our peanut butter jar; we can only store peanut butter!

The first basic variable type that we will discuss is the integer (int). Ints are whole numbers that don’t have a decimal. They can be positive or negative as long as they don’t have a decimal. The following code provides a demonstration of creating an int. Notice that the equal sign is used to assign the value 3 to the variable named myint. For simplicity sake, I recommend using only letters and underscores in your variable names. Avoid using any keywords (ie: for, in, while, if, etc) in your variable names. Following these recommendations will help you avoid any invalid variable names!

#variables-in-python #python3 #python #programming #variables #basic variable types in python

Set the Path for Python in Windows | Liquid Web Knowledge Base

Python is a powerful programming language that is scalable and uses code that is readable and clear for all types of projects. Python is also available across a number of operating systems, making it a popular choice for developers. If you are using Python on your Windows operating system, you may need to adjust your System Environment Variables to simplify utilizing Python on your server.

Method 1

The latest Python installer for Windows can set the System Environment Variable Path automatically if selected during the installation process.

Method 2

This method involves modifying the path of an existing Python installation. To verify if the path setting is correct or current, follow these steps.

Step 1.

Open an administrative command prompt by going to

Start > Windows System > Command Prompt.

Next, right-click on the command prompt icon, choose More, then choose “run as administrator“.

Step 2.

Once the Type in the python command, and then press Enter. If the System Variable Path is correctly set, you should receive output similar to what is shown below.

When using Powershell, the output will look like this.

If an error is seen indicating that the Python command is unknown, but we have confirmed that Python is installed and can be launched from within its directory, we will need to add the Python path to the System Environment Variables.

#tutorials #environment #environment variables #iis #powershell #python #python 3 #system variables #user variables #windows