Pull Value Out Of Map

index.ts

type itemMap<T> = {
    [itemName: string]: T
}

type Environments = {
    [x: string]: Environment
}

export enum Environment {
    /* eslint-disable no-unused-vars */
    STAGING = "staging",
    FRONTEND_STAGING = "frontend-staging",
    PRODUCTION = "production",
    /* eslint-enable no-unused-vars */
}

export const pullValueOutOfMap = <T>(
    map: itemMap<T>,
    keyName: string,
    errorMessage: string = ""
): T => {
    const value = map[keyName]
    if (!value) {
        throw new Error(
            `Test Error: We didn't expect "${keyName}" and didn't have it in our map. The properties our map has are:\n\n${Object.keys(
                map
            ).join("\n")}${errorMessage ? `\n\n${errorMessage}\n\n` : ""}`
        )
    }
    return value
}

export const environments: Environments = {
    staging: Environment.STAGING,
    "frontend-staging": Environment.FRONTEND_STAGING,
    production: Environment.PRODUCTION,
}

const getEnvironment = (): Environment => {
    const environment = process.env.ENVIRONMENT
    return pullValueOutOfMap(
        environments,
        environment,
        "You must set the environment in your .env file"
    )
}

const environment = getEnvironment()

console.log(`Running tests in "${environment}" environment`)

/**
 * ENVIRONMENT=staging node dist/u.js
 * Running tests in "staging" environment
 */