过去几天我一直在玩rxjs和redux-observable,并且很难找到一种方法来测试 Observable.ajax 。我有以下史诗,它向https://jsonplaceholder.typicode.com/创建了一个请求,
export function testApiEpic (action$) {
return action$.ofType(REQUEST)
.switchMap(action =>
Observable.ajax({ url, method })
.map(data => successTestApi(data.response))
.catch(error => failureTestApi(error))
.takeUntil(action$.ofType(CLEAR))
)
}
其中,
export const REQUEST = 'my-app/testApi/REQUEST'
export const SUCCESS = 'my-app/testApi/SUCCESS'
export const FAILURE = 'my-app/testApi/FAILURE'
export const CLEAR = 'my-app/testApi/CLEAR'
export function requestTestApi () {
return { type: REQUEST }
}
export function successTestApi (response) {
return { type: SUCCESS, response }
}
export function failureTestApi (error) {
return { type: FAILURE, error }
}
export function clearTestApi () {
return { type: CLEAR }
}
在浏览器中运行时代码可以正常工作,但在使用Jest进行测试时则不行。
我试过了,
1)根据https://redux-observable.js.org/docs/recipes/WritingTests.html创建测试。 store.getActions()仅返回{type:REQUEST}。
const epicMiddleware = createEpicMiddleware(testApiEpic)
const mockStore = configureMockStore([epicMiddleware])
describe.only('fetchUserEpic', () => {
let store
beforeEach(() => {
store = mockStore()
})
afterEach(() => {
epicMiddleware.replaceEpic(testApiEpic)
})
it('returns a response, () => {
store.dispatch({ type: REQUEST })
expect(store.getActions()).toEqual([
{ type: REQUEST },
{ type: SUCCESS, response }
])
})
})
2)根据Redux-observable: failed jest test for epic创建测试。它返回
超时 - 在jasmine.DEFAULT_TIMEOUT_INTERVAL指定的超时时间内未调用异步回调。
it('returns a response', (done) => {
const action$ = ActionsObservable.of({ type: REQUEST })
const store = { getState: () => {} }
testApiEpic(action$, store)
.toArray()
.subscribe(actions => {
expect(actions).to.deep.equal([
{ type: SUCCESS, response }
])
done()
})
})
有人能指出我测试Observable.ajax的正确方法是什么?
答案 0 :(得分:6)
我会从StackOverflow中跟随第二个例子。为了使它工作,你需要做一些小的调整。您需要使用某种形式的依赖注入,而不是在史诗文件中导入Observable.ajax
并直接使用该引用。一种方法是在创建中间件时将其提供给中间件。
import { ajax } from 'rxjs/observable/dom/ajax';
const epicMiddleware = createEpicMiddleware(rootEpic, {
dependencies: { ajax }
});
我们作为dependencies
传递的对象将作为第三个参数
export function testApiEpic (action$, store, { ajax }) {
return action$.ofType(REQUEST)
.switchMap(action =>
ajax({ url, method })
.map(data => successTestApi(data.response))
.catch(error => failureTestApi(error))
.takeUntil(action$.ofType(CLEAR))
);
}
或者,您无法使用中间件的dependencies
选项,而只使用默认参数:
export function testApiEpic (action$, store, ajax = Observable.ajax) {
return action$.ofType(REQUEST)
.switchMap(action =>
ajax({ url, method })
.map(data => successTestApi(data.response))
.catch(error => failureTestApi(error))
.takeUntil(action$.ofType(CLEAR))
);
}
你选择哪一个,当我们测试史诗时,我们现在可以直接调用它并为它提供我们自己的模拟。以下是成功/错误/取消路径的示例这些未经测试且可能存在问题,但应该为您提供一般性的想法
it('handles success path', (done) => {
const action$ = ActionsObservable.of(requestTestApi())
const store = null; // not used by epic
const dependencies = {
ajax: (url, method) => Observable.of({ url, method })
};
testApiEpic(action$, store, dependencies)
.toArray()
.subscribe(actions => {
expect(actions).to.deep.equal([
successTestApi({ url: '/whatever-it-is', method: 'WHATEVERITIS' })
])
done();
});
});
it('handles error path', (done) => {
const action$ = ActionsObservable.of(requestTestApi())
const store = null; // not used by epic
const dependencies = {
ajax: (url, method) => Observable.throw({ url, method })
};
testApiEpic(action$, store, dependencies)
.toArray()
.subscribe(actions => {
expect(actions).to.deep.equal([
failureTestApi({ url: '/whatever-it-is', method: 'WHATEVERITIS' })
])
done();
});
});
it('supports cancellation', (done) => {
const action$ = ActionsObservable.of(requestTestApi(), clearTestApi())
const store = null; // not used by epic
const dependencies = {
ajax: (url, method) => Observable.of({ url, method }).delay(100)
};
const onNext = chai.spy();
testApiEpic(action$, store, dependencies)
.toArray()
.subscribe({
next: onNext,
complete: () => {
onNext.should.not.have.been.called();
done();
}
});
});
答案 1 :(得分:0)
第一种方式:
首先,使用isomorphic-fetch而不是Observable.ajax来支持nock,就像这样
const fetchSomeData = (api: string, params: FetchDataParams) => {
const request = fetch(`${api}?${stringify(params)}`)
.then(res => res.json());
return Observable.from(request);
};
所以我的史诗是:
const fetchDataEpic: Epic<GateAction, ImGateState> = action$ =>
action$
.ofType(FETCH_MODEL)
.mergeMap((action: FetchModel) =>
fetchDynamicData(action.url, action.params)
.map((payload: FetchedData) => fetchModelSucc(payload.data))
.catch(error => Observable.of(
fetchModelFail(error)
)));
然后,您可能需要一个间隔来决定何时完成测试。
describe("epics", () => {
let store: MockStore<{}>;
beforeEach(() => {
store = mockStore();
});
afterEach(() => {
nock.cleanAll();
epicMiddleware.replaceEpic(epic);
});
it("fetch data model succ", () => {
const payload = {
code: 0,
data: someData,
header: {},
msg: "ok"
};
const params = {
data1: 100,
data2: "4"
};
const mock = nock("https://test.com")
.get("/test")
.query(params)
.reply(200, payload);
const go = new Promise((resolve) => {
store.dispatch({
type: FETCH_MODEL,
url: "https://test.com/test",
params
});
let interval: number;
interval = window.setInterval(() => {
if (mock.isDone()) {
clearInterval(interval);
resolve(store.getActions());
}
}, 20);
});
return expect(go).resolves.toEqual([
{
type: FETCH_MODEL,
url: "https://test.com/assignment",
params
},
{
type: FETCH_MODEL_SUCC,
data: somData
}
]);
});
});
享受它:)