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Environment Vars

Get run-time environment variables for immutable builds

Version

Installation​

NPM​

npm install @availity/env-var

Yarn​

yarn add @availity/env-var

Usage​

envVar (default export)​

This function accepts an object, and will return a value based on what environment you are in. You can also pass in a window override as well as a default value.

import envVar from '@availity/env-var';

const myEnvVal = envVar(values, windowOverride, defaultValue);

export default myEnvVal;

Required args​

  • values: An object with keys which match the name of the potential environments. The value of the give for the current environment will be returned

Optional args​

  • windowOverride: String or Window Object which can be used to override the window which is used to determine the current hostname (which is used to determine the current environment)
    • When string, the string will be takes an a fully qualified URL and the hostname will be parsed from it.
    • When Window Object, the location hostname will be used.
  • defaultValue: The value to be returned when one does not exist for the specified environment. If no default is provided, then the function will use the value specified for local

Example​

import envVar from '@availity/env-var';

/*
    myEnvVal will be different depending on the environment the code runs in
        prod: myEnvVal will be '123'
        qa: myEnvVal will be '234'
        test: myEnvVal will be '345' (defaults to local if env is not found)
*/
const myEnvVal = envVar({ prod: '123', qa: '234', local: '345' });

export default myEnvVal;

setEnvironments​

Set the potential environments and the tests used to determine which environment the code is currently being executed in.

import { setEnvironments } from '@availity/env-var';

setEnvironments(environments, override);

Required args​

  • environments: An object with keys which match the name of the potential environments and the values are the tests which are ran to determine if the environment is the current one.

These tests can be

  • String: A string will be used to check an exact match.
  • Regular Expression: A regex will be tested with the domain.
  • Function: The function will be called and the result should be a boolean indicating if the environment is the current environment.
  • Array: An array containing any of the above types.

Optional args​

  • override: Boolean, when true possibleEnvironments will replace the existing environments instead of merging.

Example​

import { setEnvironments } from '@availity/env-var';

setEnvironments({
  local: ['127.0.0.1', 'localhost'],
  test: [/^t(?:(?:\d\d)|(?:est))-apps$/],
  qa: [/^q(?:(?:\d\d)|(?:ap?))-apps$/],
  prod: [/^apps$/],
  myEnv: ['custom-stuff-here'],
});

getSpecificEnv​

Get the specific current environment, without rolling up to the general environment. Whereas envVar treats the t01 environment as test, for example, getSpecificEnv returns 't01' for the t01 environment.

import { getSpecificEnv } from '@availity/env-var';

const specificEnv = getSpecificEnv(windowOverride);

Required args​

None

Optional args​

  • windowOverride: String or Window Object which can be used to override the window which is used to determine the current hostname (which is used to determine the current environment)
    • When string, the string will be takes an a fully qualified URL and the hostname will be parsed from it.
    • When Window Object, the location hostname will be used.

Example​

import { getSpecificEnv } from '@availity/env-var';

/*
depending on the environment this code runs in, specificEnv would be something different,
like 't01' or 'stg' or 'prod'
*/
const specificEnv = getSpecificEnv();

setSpecificEnvironments​

Set the tests that will be used to determine the specific environment the code is currently being executed in.

import { setSpecificEnvironments } from '@availity/env-var';

setSpecificEnvironments(environments, override);

Required args​

  • environments: An array of objects with the following keys:
    • regex: the regular expression to match against the current subdomain
    • fn: the function to run to return the name of the environment as a string

The code will iterate through the objects, matching the subdomain against the regex. If the regex matches, the code calls the corresponding fn, passing an object containing the match (capturing groups), subdomain, and pathname. The iteration stops when it receives a non-empty answer from a function or when it reaches the end, in which case it returns 'local'.

Optional args​

  • override: Boolean, when true possibleEnvironments will replace the existing environments instead of merging.

Example​

import { setSpecificEnvironments } from '@availity/env-var';

setSpecificEnvironments([
  {
    regex: /^(?:(.*)-)?apps$/,
    fn: (options) => options.match[1] || 'prod',
  },
  {
    regex: /.*?\.(?:av|aw|gc)(n|p)$/,
    fn: (options) => options.subdomain || options.pathname.split('/')[2],
  },
]);