I started developing an app in Angular + Ionic Framework.
My problem is that I don't know how to define the type on a returned object to be able to retrieve specific attributes.
I think this is a common problem but I couldn't find the proper results using google.
When I try to return my authentication token from device storage, which looks something like
{
key:'authData',
value: token
}
I am not able to compile as my value attribute is not known on the returned storedData field.
error TS2339: Property 'value' does not exist on type 'unknown'.
return from(Storage.get({ key: 'authData' })).pipe(map(storedData => {
if (!storedData || !storedData.value) {
return null;
}
const parsedData = JSON.parse(storedData.value)
}
So I am looking for some type to define the interface type on the storedData object. Kind regards!
You must declare a model in the top of your file
interface StoredData {
key: string;
value: string;
}
And then later in your code:
return from(Storage.get({ key: 'authData' })).pipe(map(storedData: StoredData => {
if (!storedData || !storedData.value) {
return null;
}
const parsedData = JSON.parse(storedData.value)
}
Alternatively you can cheat the linter with:
return from(Storage.get({ key: 'authData' })).pipe(map(storedData => {
if (!storedData || !storedData['value']) {
return null;
}
const parsedData = JSON.parse(storedData['value'])
}