We are currently using the msal library and are in the process of converting our javaScript code to TypeScript.
In the screenshot below, TypeScript correctly identifies the expected type for cacheLocation, which can be either the string localStorage, the string sessionStorage, or undefined. However, when attempting to assign a variable holding one of these values, it fails:
The issue could be resolved by using the following syntax. The drawback in this scenario is that an incorrect value is not flagged as incorrect:
After consulting the TS documentation on Type Assertions, it states that this behavior is intentional, with the developer being responsible for ensuring correct types. I had expected TypeScript to throw an error if an unknown value was used.
Is there a more efficient way to handle this? Or is this simply the standard practice? Apologies if this question sounds naive, as I am still learning TypeScript.
Code
import * as config from 'src/app-config.json'
import { Configuration, CacheLocation } from 'msal'
const test = 'wrongValue'
export function MSALConfigFactory(): Configuration {
return {
auth: {
clientId: config.auth.clientId,
authority: config.auth.authority,
validateAuthority: true,
redirectUri: config.auth.redirectUri,
postLogoutRedirectUri: config.auth.postLogoutRedirectUri,
navigateToLoginRequestUrl: true,
},
cache: {
cacheLocation: test as CacheLocation,
storeAuthStateInCookie: false,
},
}
}