Javascript 如何在redux observable中正确使用forkJoin?
我正在使用redux observable 我试图在所有附件分别上传后发送邮件 此发送邮件API的过程是Javascript 如何在redux observable中正确使用forkJoin?,javascript,redux,rxjs,rxjs5,redux-observable,Javascript,Redux,Rxjs,Rxjs5,Redux Observable,我正在使用redux observable 我试图在所有附件分别上传后发送邮件 此发送邮件API的过程是 将邮件内容添加到草稿中 在草稿中单独添加附件 上传所有附件后,从草稿发送邮件 现在,下面的代码可以分别成功上载所有附件。然而,我不知道如何等待它们全部完成 学习之后,我认为我需要使用forkJoin,但是我没有弄清楚在这种情况下如何正确使用它 export const addMailContentSucceedEpic = (action$, store) => action$
forkJoin
,但是我没有弄清楚在这种情况下如何正确使用它
export const addMailContentSucceedEpic = (action$, store) =>
action$
.ofType(ADD_MAIL_CONTENT_SUCCEED)
.expand(action => { // expand here helps upload all attachments separately
const restAttachments = removeFirstAttachment(action.payload.attachments);
if (isEmpty(restAttachments)) return Observable.empty();
return Observable.of({
...action,
payload: {
...action.payload,
attachments: restAttachments
}
});
})
.map(action => addAttachment({ mailId: action.payload.mailId, attachment: first(action.payload.attachments) }));
export const addAttachmentEpic = (action$, store) =>
action$
.ofType(ADD_ATTACHMENT)
.mergeMap(action => getBase64FromFile(action))
.mergeMap(action =>
ajax
.patch(url, { base64: action.payload.base64 })
.map(() => addAttachmentSucceed({ mailId: action.payload.mailId }))
.catch(addAttachmentFailed)
);
export const addAttachmentSucceedEpic = (action$, store) =>
action$
.ofType(ADD_ATTACHMENT_SUCCEED)
// Here is wrong, I need wait all attachments be uploaded
// I tried to add a global `let = tasks$[];` on the top, but I am not clear where and how I can push each task (add attachment) to it
// Then add .mergeMap(action => Observable.forkJoin(tasks$)) here, but it probably wrong to be added after .ofType(ADD_ATTACHMENT_SUCCEED)
// In my mind, it needs to be after something `ADD_ALL_ATTACHMENTS_SUCCEED`
.map(action => sendMailFromDraft({ mailId: action.payload.mailId }));
更新:
我将尝试更改为下面的结构
也许我可以将addAttachments$
作为有效负载(?)传递,或者将其创建为全局变量。稍后我会提供更多更新
const addAttachments$ = [
ajax.patch(url, { base64: getBase64(first(action.payload.attachments) })),
ajax.patch(url, { base64: getBase64(second(action.payload.attachments) })),
ajax.patch(url, { base64: getBase64(third(action.payload.attachments) })),
// ...
];
export const addMailContentSucceedEpic = (action$, store) =>
action$
.ofType(ADD_MAIL_CONTENT_SUCCEED)
.mergeMap(action =>
Observable.forkJoin(addAttachments$)
.map(() => sendMailFromDraft({ mailId: action.payload.mailId }))
)
.catch(/* ... */);
这是我最后的解决办法 因为读取文件也是异步的,所以在这个解决方案中有两个
forkJoin
一个forkJoin
用于等待读取所有文件。另一个forkJoin
用于等待上传所有附件
对于代码中的getBase64FromFile$
,请检查
export const addMailContentSucceedEpic=(action$,store)=>
行动$
.of类型(添加邮件内容成功)
.mergeMap(操作=>addTasks$(操作))
.mergeMap(action=>Observable.forkJoin(action.payload.posts$)
.map(()=>sendMailFromDraft({mail:action.payload.mail}))
);
函数getPosts(base64Array,action){
让帖子$=[];
for(设i=0;igetPosts(base64Array,action));
}
代码中有forkJoin
的地方在哪里?@martin刚刚添加了更多!感谢您回来并添加解决方案!非常有助于子孙后代。@Jayphapps不,你对我们的帮助超出了我们的能力,谢谢!
export const addMailContentSucceedEpic = (action$, store) =>
action$
.ofType(ADD_MAIL_CONTENT_SUCCEED)
.mergeMap(action => addTasks$(action))
.mergeMap(action => Observable.forkJoin(action.payload.posts$)
.map(() => sendMailFromDraft({ mail: action.payload.mail }))
);
function getPosts(base64Array, action) {
let posts$ = [];
for (let i = 0; i < base64Array.length; ++i) {
posts$ = [...posts$, ajax.patch(url, { base64: base64Array[i] })];
}
return {
...action,
payload: {
...action.payload,
posts$
}
};
}
function addTasks$(action) {
let readFiles$ = [];
for (let i = 0, attachmentIds = Object.keys(action.payload.attachments); i < attachmentIds.length; ++i) {
const attachmentId = attachmentIds[i];
const attachment = action.payload.attachments[attachmentId];
readFiles$ = [...readFiles$, getBase64FromFile$(attachment)];
}
return Observable.forkJoin(readFiles$)
.map(base64Array => getPosts(base64Array, action));
}