To inject context into a Redux Saga, you can use the `getContext` effect provided by Redux Saga. Here's how you can do it:
1. Create a Context Object: Create a context object that contains the values you want to inject into your sagas. This can be a singleton API service or any other shared value across your application.
2. Pass the Context Object to the Saga Middleware: When creating the saga middleware, pass the context object as an option. This sets the context for all sagas that are run using this middleware.
3. Use `getContext` Effect in Your Saga: In your saga, use the `getContext` effect to retrieve the context values. This allows you to access the shared values without having to import them statically.
Here is an example of how you can use `getContext` in a saga:
javascript
import { call, getContext } from "redux-saga/effects";
// No more API import:
// import api from './api'
export function* fetchInventorySaga() {
// Get the api value out of the shared context:
const api = yield getContext("api");
const inventory = yield call(api.getInventory);
// Do something with the inventory data...
By using `getContext`, you can decouple your sagas from statically-declared singletons and make your code more modular and testable.
Here is a more detailed example of how you can set up context in your main application and use it in your sagas:
javascript
import createSagaMiddleware from "redux-saga";
import api from "./api";
const sagaMiddleware = createSagaMiddleware({
context: {
api, // our singleton API value
},
});
const store = createStore(reducer, applyMiddleware(sagaMiddleware));
In this example, the `api` singleton is set as the context for all sagas that are run using this middleware. Then, in your sagas, you can use `getContext` to access the `api` value:
javascript
import { call, getContext } from "redux-saga/effects";
export function* fetchInventorySaga() {
const api = yield getContext("api");
const inventory = yield call(api.getInventory);
// Do something with the inventory data....
}
By using `getContext`, you can manage shared values across your application in a more organized and testable way.
Citations:[1] https://www.npmjs.com/package/redux-sagas-injector
[2] https://faraday.ai/blog/context-in-redux-saga
[3] https://github.com/redux-saga/redux-saga/issues/2050
[4] https://redux-saga.js.org/docs/api/
[5] https://www.youtube.com/watch?v=x5_9_PSlVYo