How to update the state of an object in react-redux - reactjs

Question

My question might sound stupid but I swear my brain freeze, I google it for answer but honestly I don't even know what should I search for. So basically I have a reducer, usually when I'm using redux I'm using arrays and my reducers look like this:
import { FETCH_ALL, CREATE, UPDATE, DELETE } from '../constants/actionTypes';
export default (posts = [], action) => {
switch (action.type) {
case FETCH_ALL:
return action.payload;
case CREATE:
return [...posts, action.payload];
case UPDATE:
return posts.map((post) => post._id === action.payload._id ? action.payload : post);
case DELETE:
return posts.filter((post) => post._id !== action.payload);
default:
return posts;
}
};
And now I only have an object, and I really don't know what to write on case UPDATE, I mean I'm not looping through and find my updated object and that process.
My question is how can I update if I only have an object
import { FETCH_PROFILE, UPDATE_PROFILE } from '../constants';
export default (profile= {}, action) => {
switch (action.type) {
case FETCH_PROFILE:
return action.payload;
case UPDATE_PROFILE:
return ;
default:
return profile;
}
};
like here, in that case UPDATE_PROFILE, what should I write to make it work, in my backend everything going well, the return is an object with the updated user.
I know my question is stupid, but please be kind! Thank you in advance
Unexpected token, expected "," (8:32)
6 | return action.payload;
7 | case UPDATE_PROFILE:
> 8 | return {...profile, action.payload};
| ^
9 | default:
10 | return profile;
11 | }

Answer 1

For object you will use spread operator just like in an array:
import { FETCH_PROFILE, UPDATE_PROFILE } from '../constants';
export default (profile= {}, action) => {
switch (action.type) {
case FETCH_PROFILE:
return action.payload;
case UPDATE_PROFILE:
return {...profile, action.payload};
default:
return profile;
}
};
More about it here.

Answer 2

In your update profile, pass the entire object after updating.
For eg:
let profiles =[{name:"foo",id:1},{name:"bar",id:2},{name:"baz",id:3}]
let updateProfile = [{id:2,name:"gaurav"}]
then, first update the profiles with updated profile, that is,
const updatedProfiles = profiles.map(item=>item.id===?:updatedProfile:item)
then, simply pass updatedProfiles in action.payload,
in your reducer, it will be then
case UPDATE_PROFILE:
return action.payload;