Node.js / Javascript 多重递归承诺在视图中返回
Posted
技术标签:
【中文标题】Node.js / Javascript 多重递归承诺在视图中返回【英文标题】：Node.js / Javascript multiple recursive promise to return at view 【发布时间】：2019-12-19 08:32:13 【问题描述】：我目前有一个包含多个递归调用的算法，我希望每个人都返回该算法以巩固我的结果
问题是递归调用太多，我不再知道如何返回我的合并结果
我尝试在每个promise的末尾通过结果数检查promise的数量来做出promise.all，但是我得到的结果表明我正在做出几个http响应
在这个版本中，我在所有承诺执行或添加到我的承诺列表之前返回结果。
var https = require('https');
var moment = require('moment');
app.get('/detail/:issue', function (req, res)
var promises = [];
var jsonResult =
total:
daysSpent: 0,
daysEstimated: 0,
daysRemaining: 0,
cost: 0
,
issues:
;
var getIssue = function (key)
/**
* Récupération des imputations par projet.
*/
promises.push(new Promise(function (resolve)
var options = Object.assign(, app.locals.data.jira);
options.path = "/jira/rest/api/2/issue/issueKey"
.replace('issueKey', key);
https.request(options, (resp) =>
let body = '';
resp.on('data', (chunk) =>
body += chunk;
);
resp.on('end', () =>
var issue = JSON.parse(body);
if (issue.fields.issuetype.name == 'Epic')
getEpic(issue.key);
else
jsonResult.issues[issue.key] =
key: issue.key,
numberTicket: issue.fields.customfield_10267 === null ? "-" : issue.fields.customfield_10267,
icon: issue.fields.issuetype.iconUrl,
name: issue.fields.summary,
status: issue.fields.status.name,
daysEstimated: issue.fields.issuetype.subtask ? (((issue.fields.timeoriginalestimate || 0) / 3600) / 7) : ((issue.fields.customfield_11901 || 0) / 7),
daysRemaining: issue.fields.issuetype.subtask ? (((issue.fields.timeoriginalestimate || 0) / 3600) / 7) : ((issue.fields.customfield_11901 || 0) / 7),
hoursSpent: 0,
daysSpent: 0,
cost: 0,
parent: issue.fields.parent === undefined ? issue.key : issue.fields.parent.key,
detail: ,
subtask: issue.fields.issuetype.subtask,
worklog: issue.fields.worklog.total != 0
jsonResult.total.daysEstimated += ((issue.fields.customfield_11901 || 0) / 7);
jsonResult.total.daysRemaining += ((issue.fields.customfield_11901 || 0) / 7);
if (issue.fields.subtasks != false)
for (let e in issue.fields.subtasks)
e = issue.fields.subtasks[e];
getIssue(e.key);
;
if (issue.fields.worklog.total != 0)
getWorklog(issue.key);
resolve();
);
).on("error", (e) =>
console.log("Error: " + e.message);
).end();
));
var getEpic = function (key)
/**
* Récupération des imputations par projet.
*/
promises.push(new Promise(function (resolve)
var postData = JSON.stringify(
"jql": "'Epic link' = issueKey"
.replace('issueKey', key),
"maxResults": -1,
"fields": [
"issuekey"
]
);
var options = Object.assign(, app.locals.data.jira);
options.path = "/jira/rest/api/2/search";
options.method = 'POST';
options.headers =
'Content-Type': 'application/json',
'Cache-Control': 'no-cache',
"Content-Length": Buffer.byteLength(postData)
;
var req = https.request(options, (resp) =>
let body = '';
resp.on('data', (chunk) =>
body += chunk;
);
resp.on('end', () =>
var issues = JSON.parse(body).issues;
for (let issue in JSON.parse(body).issues)
issue = issues[issue];
getIssue(issue.key);
;
resolve();
);
).on("error", (e) =>
console.log("Error: " + e.message);
);
req.write(postData);
req.end();
));
var getWorklog = function (key)
/**
* Récupération des imputations par projet.
*/
promises.push(new Promise(function (resolve)
var options = Object.assign(, app.locals.data.jira);
options.path = "/jira/rest/api/2/issue/issueKey/worklog"
.replace('issueKey', key);
https.request(options, (resp) =>
let body = '';
resp.on('data', (chunk) =>
body += chunk;
);
resp.on('end', () =>
var worklogs = JSON.parse(body).worklogs;
for (let e in worklogs)
e = worklogs[e];
if (jsonResult.issues[key].detail[e.author.key] == undefined)
jsonResult.issues[key].detail[e.author.key] =
name: e.author.displayName,
hoursSpent: 0,
daysSpent: 0,
cost: 0
jsonResult.issues[key].hoursSpent += e.timeSpentSeconds / 3600;
jsonResult.issues[key].detail[e.author.key].hoursSpent += e.timeSpentSeconds / 3600;
if (app.locals.data.scr[moment(e.started).format("Y")] !== undefined && app.locals.data.scr[moment(e.started).format("Y")][e.author.emailAddress] !== undefined)
var time = (e.timeSpentSeconds / 3600) / app.locals.data.scr[moment(e.started).format("Y")][e.author.emailAddress].modality;
var cost = time * app.locals.data.scr[moment(e.started).format("Y")][e.author.emailAddress].scr;
jsonResult.issues[key].detail[e.author.key].daysSpent += time;
jsonResult.issues[key].detail[e.author.key].cost += cost;
jsonResult.issues[key].daysSpent += time;
jsonResult.issues[key].cost += cost;
jsonResult.issues[key].daysRemaining -= time;
;
resolve();
);
).on("error", (e) =>
console.log("Error: " + e.message);
).end();
));
getIssue(req.params.issue);
Promise.all(promises).then(function ()
res.json(jsonResult);
);
);
【问题讨论】：
递归对于某些问题可能是一种很好的技术；在这种情况下，它增加了太多的认知开销（这意味着它很难跟踪程序执行）。您是否尝试过迭代方法？什么条件终止递归？将所有这些函数拆分为单独的文件也很有用。 我建议你使用async/await (developer.mozilla.org/en-US/docs/Web/javascript/Reference/…) 而不是promise。这将允许您编写函数调用，就好像它们是同步函数一样
不可能进行迭代，因为我事先不知道必须处理的元素数量。我处理多达 3 个层次级别的数据，其中第 2 级可以有 X 个子级。我将再次尝试等待/异步解决方案，这是我认为我可以做到的一种方法，但 nodeJS 告诉我我不明白
【参考方案1】：
我的问题已经解决了！
var https = require('https');
var moment = require('moment');
app.get('/detail/:issue', function (req, res)
var jsonResult =
total:
daysSpent: 0,
daysEstimated: 0,
daysRemaining: 0,
cost: 0
,
issues:
;
var getIssue = function (key)
/**
* Récupération des imputations par projet.
*/
return new Promise(function (resolve)
var options = Object.assign(, app.locals.data.jira);
options.path = "/jira/rest/api/2/issue/issueKey"
.replace('issueKey', key);
https.request(options, (resp) =>
let body = '';
resp.on('data', (chunk) =>
body += chunk;
);
resp.on('end', () =>
var promises = [];
var issue = JSON.parse(body);
if (issue.fields.issuetype.name == 'Epic')
promises.push(getEpic(issue.key));
else
jsonResult.issues[issue.key] =
key: issue.key,
numberTicket: issue.fields.customfield_10267 === null ? "-" : issue.fields.customfield_10267,
icon: issue.fields.issuetype.iconUrl,
name: issue.fields.summary,
status: issue.fields.status.name,
daysEstimated: issue.fields.issuetype.subtask ? (((issue.fields.timeoriginalestimate || 0) / 3600) / 7) : ((issue.fields.customfield_11901 || 0) / 7),
daysRemaining: issue.fields.issuetype.subtask ? (((issue.fields.timeoriginalestimate || 0) / 3600) / 7) : ((issue.fields.customfield_11901 || 0) / 7),
hoursSpent: 0,
daysSpent: 0,
cost: 0,
parent: issue.fields.parent === undefined ? issue.key : issue.fields.parent.key,
detail: ,
subtask: issue.fields.issuetype.subtask,
worklog: issue.fields.worklog.total != 0
jsonResult.total.daysEstimated += ((issue.fields.customfield_11901 || 0) / 7);
jsonResult.total.daysRemaining += ((issue.fields.customfield_11901 || 0) / 7);
if (issue.fields.worklog.total != 0)
promises.push(getWorklog(issue.key));
if (issue.fields.subtasks != false)
for (let e in issue.fields.subtasks)
e = issue.fields.subtasks[e];
promises.push(getIssue(e.key));
;
Promise.all(promises).then(function ()
resolve();
);
);
).on("error", (e) =>
console.log("Error: " + e.message);
).end();
);
var getEpic = function (key)
/**
* Récupération des imputations par projet.
*/
return new Promise(function (resolve)
var postData = JSON.stringify(
"jql": "'Epic link' = issueKey"
.replace('issueKey', key),
"maxResults": -1,
"fields": [
"issuekey"
]
);
var options = Object.assign(, app.locals.data.jira);
options.path = "/jira/rest/api/2/search";
options.method = 'POST';
options.headers =
'Content-Type': 'application/json',
'Cache-Control': 'no-cache',
"Content-Length": Buffer.byteLength(postData)
;
var req = https.request(options, (resp) =>
let body = '';
resp.on('data', (chunk) =>
body += chunk;
);
resp.on('end', () =>
var promises = [];
var issues = JSON.parse(body).issues;
for (let issue in JSON.parse(body).issues)
issue = issues[issue];
promises.push(getIssue(issue.key));
;
Promise.all(promises).then(function ()
resolve();
);
);
).on("error", (e) =>
console.log("Error: " + e.message);
);
req.write(postData);
req.end();
);
var getWorklog = function (key)
/**
* Récupération des imputations par projet.
*/
return new Promise(function (resolve)
var options = Object.assign(, app.locals.data.jira);
options.path = "/jira/rest/api/2/issue/issueKey/worklog"
.replace('issueKey', key);
https.request(options, (resp) =>
let body = '';
resp.on('data', (chunk) =>
body += chunk;
);
resp.on('end', () =>
var worklogs = JSON.parse(body).worklogs;
for (let e in worklogs)
e = worklogs[e];
if (jsonResult.issues[key].detail[e.author.key] == undefined)
jsonResult.issues[key].detail[e.author.key] =
name: e.author.displayName,
hoursSpent: 0,
daysSpent: 0,
cost: 0
jsonResult.issues[key].hoursSpent += e.timeSpentSeconds / 3600;
jsonResult.issues[key].detail[e.author.key].hoursSpent += e.timeSpentSeconds / 3600;
if (app.locals.data.scr[moment(e.started).format("Y")] !== undefined && app.locals.data.scr[moment(e.started).format("Y")][e.author.emailAddress] !== undefined)
var time = (e.timeSpentSeconds / 3600) / app.locals.data.scr[moment(e.started).format("Y")][e.author.emailAddress].modality;
var cost = time * app.locals.data.scr[moment(e.started).format("Y")][e.author.emailAddress].scr;
jsonResult.issues[key].detail[e.author.key].daysSpent += time;
jsonResult.issues[key].detail[e.author.key].cost += cost;
jsonResult.issues[key].daysSpent += time;
jsonResult.issues[key].cost += cost;
jsonResult.issues[key].daysRemaining -= time;
if (jsonResult.issues[key].subtask)
jsonResult.issues[jsonResult.issues[key].parent].hoursSpent += e.timeSpentSeconds / 3600;
jsonResult.issues[jsonResult.issues[key].parent].daysSpent += time;
jsonResult.issues[jsonResult.issues[key].parent].cost += cost;
jsonResult.issues[jsonResult.issues[key].parent].daysRemaining -= time;
jsonResult.total.daysSpent += time;
jsonResult.total.cost += cost;
jsonResult.total.daysRemaining -= time;
;
resolve();
);
).on("error", (e) =>
console.log("Error: " + e.message);
).end();
);
getIssue(req.params.issue).then(function ()
res.json(jsonResult);
);
);
每个方法都等待其所有子方法结束才能结束
【讨论】：
以上是关于Node.js / Javascript 多重递归承诺在视图中返回的主要内容，如果未能解决你的问题，请参考以下文章
Node.js资讯 | ES6 下的函数式:递归模式；JavaScript 深拷贝性能分析