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getEnvVar and getEnvFlag type-safe functions
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| type EnvVarName = | |
| | 'FOO' | |
| | 'BAR'; | |
| type EnvFlagName = | |
| | 'IS_FOO' | |
| | 'IS_BAR'; | |
| export function getEnvVar<T extends string = EnvVarName | EnvFlagName>( | |
| name: T, | |
| params?: { | |
| default?: string; | |
| }, | |
| ): string; | |
| export function getEnvVar<T extends string = EnvVarName | EnvFlagName>( | |
| name: T, | |
| params?: { | |
| default?: string; | |
| optional: true; | |
| }, | |
| ): string | undefined; | |
| export function getEnvVar<T extends string = EnvVarName | EnvFlagName>( | |
| name: T, | |
| params?: { | |
| default?: string; | |
| optional?: true; | |
| }, | |
| ): string | undefined { | |
| const res = process.env[name] ?? params?.default; | |
| if (typeof res === 'undefined') { | |
| if (params?.optional) { | |
| return undefined; | |
| } | |
| throw new Error(`Environment variable '${name}' is not defined`); | |
| } | |
| return res; | |
| } | |
| export function getEnvFlag<T extends string = EnvFlagName>(name: T): boolean { | |
| const str = getEnvVar(name, { default: '0' }); | |
| return ['1', 'true'].includes(str); | |
| } |
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