`getStatus(state, statusLocation, [treatNullAsPending])`

Returns an object with boolean values representing the request status of a particular CRUD action. It can also be used to aggregate multiple request statuses together.

Arguments

state (Object): Typically, the current state of the Redux store, but more generally it can be any object that has a request status somewhere deeply nested within it.
statusLocation (String|Array): A single path that points to a request status within state. If you pass an array of status locations, then they will be aggregated. For more on status locations and status aggregation, see the Notes below.
[treatNullAsPending] (Boolean): Whether or not a request status of NULL is to be considered as a pending request. Defaults to false. See Tips on when to use this.

Returns

(Object): An Object representing the status of this request for the statusLocation. It has the following shape:

  {
    null: Boolean,
    pending: Boolean,
    failed: Boolean,
    succeeded: Boolean
  }

One of these values is always true, reflecting the value of the request status. When treatNullAsPending is true, then request statuses that are "NULL" will be returned as pending: true.

Notes

Passing more than one status location will aggregate the statuses. The rules of aggregation work as follows:

If all of the requests are null, then the aggregate is null
If any of the requests are failed, then the aggregate is failed.
If no requests have failed, but some are pending, then the aggregate is pending.
If all requests have succeeded, then the aggregate has succeeded.

A status location is a string that specifies a location of a request status in your state tree. For instance "books.meta.24.readStatus" or "books.requests.dashboardSearch.status".

Keep in mind that treatNullAsPending also works when aggregating.

Examples

In this example, we pass a single status location:

import { getStatus } from 'redux-resource';
import store from './store';

const state = store.getState();
const bookDeleteStatus = getStatus(state, 'books.meta[23].deleteStatus');

In this example, we pass two locations:

import { getStatus } from 'redux-resource';
import store from './store';

const state = store.getState();
const bookReadStatus = getStatus(
  state,
  [
    'articles.meta[23].readStatus',
    'comments.requests.detailsRead.status'
  ],
  true
);

Tips

The third argument, treatNullAsPending, is useful for requests that are made when your components mount. The components will often render before the request begins, so the status of these requests will be NULL. Passing treatNullAsPending will consider these NULL states as pending: true.
If you're using React, we recommend computing your getStatus values in mapStateToProps, and then passing them in as props into your component. That way, you have access to this information in all of the lifecycle methods of your component.
The first argument, state, doesn't always need to be the state of your Redux store. For instance, if you're using this method within your component's lifecycle methods, such as componentWillReceiveProps, you may instead pass it an object that is a subset of the state. This can be useful when you're comparing a previous status against an upcoming status.

getStatus