Bre*_*ody 8 javascript reactjs redux-saga react-redux
我有一个Saga,我需要做3个异步请求,然后在后续请求中使用来自3个请求的响应.这里有一些psuedo代码来解释:
function* useOtherActionsAndSagas(action) {
try {
const [response1, response2, response3] = yield [
request1,
request2,
request3
];
const orderData = {
...response1,
...response2,
...response3,
};
const response4 = yield request4;
yield put({ type: 'SUCCESS', data: response4 });
} catch (e) {
// handle error
}
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的3个请求request1,request2并request3对应于3个独立的英雄传奇.例如,因为request1有一个Saga沿着以下线:
export function* request1(action) {
try {
const result = yield api.get(`/api/endpoint`);
yield put({...action, type: ACTION1_SUCCESS, data: result});
} catch (e) {
yield put({...action, type: ACTION1_FAIL, errors: e});
}
}
function* watchAction1() {
yield* takeLatest(ACTION1, request1);
}
export default function* () {
yield [fork(watchAction1)];
}
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其中api.get是Axios.get()的包装器.
Saga中的这个观察者连接到相应的动作/减速器.
export const ACTION1 = "actions/ACTION1";
export const ACTION1_SUCCESS = "actions/ACTION1_SUCCESS";
export const ACTION1_FAIL = "actions/ACTION1_FAIL";
const initialState = {
// Initial state
};
export default function reducer(state = initialState, action = {}) {
switch (action.type) {
case ACTION1:
// return state
case ACTION1_SUCCESS:
// return state
case ACTION1_FAIL:
// return state
};
default:
// return state;
}
}
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export function request1(data){return {type:ACTION1,data}; }
为了保持我的代码干,我希望利用父传奇中的现有动作和传奇.为此,我试过:
const [response1, response2, response3] = yield [
put({type: ACTION1, data: data1}),
put({type: ACTION2, data: data2}),
put({type: ACTION3, data: data3})
];
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这正确地启动了每个动作及其相应的传奇.但是,请求的响应在分配的变量中不可用.也就是说response1,response2并且response3是对他们的行为的引用,{type: "actions/ACTION1", data: data1}而不是对Promise的引用.
我知道可以在这个父级Saga中复制Axios请求,但是我会失去对各个请求进行成功/失败操作的奖励.
是否可以使用这样的设置?如果是这样,如何检索异步请求的响应以用于后续请求?
如果没有,完成此任务的正确方法是什么?
我可以在父传奇中使用其他Sagas的工人,如下所示:
import request1 from request1Saga;
const [response1, response2, response3] = yield [
call(request1, data1),
call(request2, data2),
call(request3, data3),
];
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在哪里request1,request2并且request3工人的功能来自其他Sagas.这样可以使用Sagas所带来的好处ACTION1_SUCCESS和ACTION1_FAIL行动.
您所需要的只是将all组合器与call效果结合起来(用于编写传奇和并行运行任务的文档):
const [response1, response2, response3] = yield all([
call(request1),
call(request2),
call(request3)
]);
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这将并行执行传奇并返回每个传奇的结果。它的工作原理是Promise.all.
上面的saga(request1到request3)需要在saga结束时返回一些数据:
export function* request1(action) {
try {
const result = yield call(url => api.get(url), `/api/endpoint`);
yield put({...action, type: ACTION1_SUCCESS, data: result});
// This will be assigned to result1
return result
} catch (e) {
yield put({...action, type: ACTION1_FAIL, errors: e});
}
}
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注意:您不需要分叉 takeEvery,因为它已经“分叉”了:
// Example of root saga:
export default function* () {
yield takeLatest(ACTION1, request1);
yield takeLatest(ACTION2, request2);
// ...
}
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