React JSX Question
Keeping data object after filtering
Small Background intro
I´m currently working the User Administration page of my project and running into a small problem here. I have a table which contains some material-ui`s Usercard. For Each user that uses my System exist´s one card. The card´s are generated from data that comes from my database and then written into a redux store.
The Admin can do several interactions with the database that changes some Userdata. To provide an easy way to find a specific user a
<TextField />All of the things mentioned here works!
The Problem
As mentioned in the Intro the data are stored in a redux store. When I filter the data, an action is dispatched
export const FILTER_ALL_USER_BY_NAME = "FILTER_ALL_USER_BY_NAME"
export const FILTER_ALL_USER_BY_DEPARTMENT = "FILTER_ALL_USER_BY_DEPARTMENT"
export default function filterAllUser(filter, filterOption){
return (dispatch, getState) => {
if(filterOption === 'name'){
return dispatch (filterUserByName(filter))
}else{
return dispatch (filteUserByDepartment(filter))
}
}
}
function filterUserByName(filter){
return {
type: FILTER_ALL_USER_BY_NAME,
filter: filter
}
}
function filteUserByDepartment(filter){
return {
type: FILTER_ALL_USER_BY_DEPARTMENT,
filter: filter
}
}
The Reducer
Even if the reducers works, it is the main reason for my problem.
Why?
It is because, when I filter the data I was not able to really filter the state, rather then return a new state object which leads me to the problem that the
allUserDatafilteredUserDataLet me explain this in code
function allUser(state = {allUserData: []}, action){
switch (action.type){
case 'REQUEST_ALL_USER':
return Object.assign({}, state, {
isFetching: true
});
case 'RECEIVE_ALL_USER':
return Object.assign({}, state, {
isFetching: false,
allUserData: action.items
});
case 'FILTER_ALL_USER_BY_NAME':
return Object.assign({}, state, {
filteredUserData: state.allUserData.filter(user => user.userNameLast.toLowerCase().indexOf(action.filter.toLowerCase()) >= 0)
});
case 'FILTER_ALL_USER_BY_DEPARTMENT':
return Object.assign({}, state, {
filteredUserData: state.allUserData.filter(user => user.departmentName.toLowerCase().indexOf(action.filter.toLowerCase()) >= 0)
});
default:
return state
}
}
But when I´m trying to filter the original state and the user removes the filter, the data that didn´t matched the filter are gone.
case 'FILTER_ALL_USERS': return allUsers.filter(user => user.userNameLast.toLowerCase().indexOf(action.filter.toLowerCase()) >= 0);
How can I filter the state, but keep the data ?
Answer
As requested, I have put together some code for you. It would be something like below.
As a side note, I would pass the filter as { field: 'userLastName', text: your filter text} as the filter criteria. Or to make it even more scalable, you can pass a filter-handler instead of text above. That way you can have any type of filter, and not just text filters.
export default function allUser(state = {allUserData: [], filters: {}, filteredUserData: []}, action){
switch (action.type){
case 'REQUEST_ALL_USER':
return {
...state,
isFetching: true
};
case 'RECEIVE_ALL_USER':
return {
...state,
isFetching: false,
allUserData: action.items,
filteredUserData: filterData(action.items, state.filters),
};
case 'FILTER_ALL_USER_BY_NAME':
{
const updatedFilters = {
...state.filters,
userNameLast: action.filter
}
return {
...state,
filteredUserData: filterData(state.allUserData, updatedFilters),
filters: updatedFilters
};
}
case 'FILTER_ALL_USER_BY_DEPARTMENT':
{
const updatedFilters = {
...state.filters,
departmentName: action.filter
}
return {
...state,
filteredUserData: filterData(state.allUserData, updatedFilters),
filters: updatedFilters
};
}
default:
return state
}
}
const filterData = (users, filters) => {
return users.filter(filterFn(filters));
};
const filterFn = filters => item => Object.keys(filters).reduce((res, filter) => {
return res && item[filter].toLowerCase().indexOf(filters[filter].toLowerCase()) >= 0;
}, true);
Unit tests
import usersReducer from './users';
describe('usersReducer', () => {
describe('RECEIVE_ALL_USER', () => {
const RECEIVE_ALL_USER = 'RECEIVE_ALL_USER';
it('should replace users in state', () => {
const initialState = { isFetching: false, allUserData: [{ name: 'A' }], filters: {}};
const newUsers = [{ name: 'B' }];
const newState = { ...initialState, allUserData: newUsers, filteredUserData: newUsers};
expect(usersReducer(initialState, { type: RECEIVE_ALL_USER, items: newUsers })).toEqual(newState);
})
})
describe('FILTER_ALL_USER_BY_NAME', () => {
let FILTER_ALL_USER_BY_NAME = 'FILTER_ALL_USER_BY_NAME';
it('should filter users by name', () => {
const initialState = { isFetching: false, allUserData: [{ userNameLast: 'Doe' }, { userNameLast: 'Smith' }], filters: {}};
const filterText = 'd';
const finalState = { isFetching: false,
allUserData: [{ userNameLast: 'Doe' }, { userNameLast: 'Smith' }],
filters: { userNameLast: filterText },
filteredUserData: [{ userNameLast: 'Doe' }]
};
expect(usersReducer(initialState, { type: FILTER_ALL_USER_BY_NAME, filter: filterText})).toEqual(finalState);
})
})
describe('FILTER_ALL_USER_BY_DEPARTMENT', () => {
let FILTER_ALL_USER_BY_DEPARTMENT = 'FILTER_ALL_USER_BY_DEPARTMENT';
it('should filter users by department', () => {
const initialState = { isFetching: false, allUserData: [{ departmentName: 'IT' }, { departmentName: 'Human Resources' }], filters: {}};
const filterText = 'it';
const finalState = {
...initialState,
filters: { departmentName: filterText },
filteredUserData: [{ departmentName: 'IT' }]
};
expect(usersReducer(initialState, { type: FILTER_ALL_USER_BY_DEPARTMENT, filter: filterText})).toEqual(finalState);
})
})
});
Source (Stackoverflow)