我正在学习 express 和 mongoose，我无法保存要保存的模式，但可以通过 console.log() 看到它
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【中文标题】我正在学习 express 和 mongoose，我无法保存要保存的模式，但可以通过 console.log() 看到它【英文标题】：I am learning express and mongoose and I cannot get a schema to save, but can see it with console.log() 【发布时间】：2020-01-20 12:29:03 【问题描述】：编辑：我认为 weekCount 在记录加载到其中之前正在保存。可能不正确地使用 find()？
我创建了一个网站来记录营地（围场）中的动物。我正在使用 express、mongo、mongoose 和 pug。
我有一个模式（见下文），它有一个类型数组：Schema.Types.ObjectId，我无法保存到 mongo。数组为空。
我有一个表格，可以获取营地名称和动物类型（奶牛、公牛、小牛）并创建一个表格。
表单显示出来，POST可以读取表单数据。表单数据被读入架构并使用console.log显示正常，但不会将整个架构保存在mongo中。
我已经阅读了很多帖子，并尝试了很多东西，例如 markModified，使用了完整的 Schema。
现在已经几个小时了，我希望能得到一些帮助。
Express mongoose 模型：
var WeekCountSchema = new Schema(
dateOfCount: type: Date ,
campCounts: [type: Schema.Types.ObjectId, ref: 'CampCount'] < ----- problem
);
var CampCountSchema = new Schema(
campName: String,
campCountDate: Date,
count:
ox: Number,
cow: Number,
bull: Number,
heifer: Number,
calf: Number,
weaner: Number
);
weekCountController:
Scroll Down to the <----
exports.weekCount_create_post = [
validator
.body("dateOfCount", "Week Count Data Required")
.toDate()
.isLength( min: 1 )
.trim(),
validator.sanitizeBody("*").escape(),
(req, res, next) =>
var weekCount = new WeekCount(
dateOfCount: req.body.dateOfCount
);
const errors = validator.validationResult(req);
if (!errors.isEmpty())
// There are errors. Render the form again with sanitized values/error messages.
console.log("ERRORS!s");
async.parallel(
camps: function(callback)
Camp.find()
.sort("name")
.exec(callback);
,
cattleClasses: function(callback)
CattleClass.find(callback);
,
function(err, results)
if (err)
return next(err);
res.render("weekCount_form",
title: "There were Errors! New Week Count",
camps: results.camps,
cattleClasses: results.cattleClasses
);
);
return;
else
// Data from form is valid.
Camp.find(, "name").exec(function(err, list_camps)
if (err)
return next(err);
CattleClass.find(, "name").exec(function(err, list_cattleClasses)
if (err)
return next(err);
var campCountArray = [];
list_camps.forEach(function(campName)
var campCount = new CampCount(
campName: campName.name
);
var emptyCount = true;
list_cattleClasses.forEach(function(cattleClassName)
var tempVar = campName.name + "." + cattleClassName.name;
var tempNum = parseInt(req.body[tempVar]);
// console.log(tempNum);
if (tempNum)
// console.log(req.body[tempVar]);
campCount.count[cattleClassName.name] = req.body[tempVar];
emptyCount = false;
else
campCount.count[cattleClassName.name] = 0;
);
if (!emptyCount)
campCount.save(function(err)
if (err)
return next(err);
);
campCountArray.push(campCount);
);
console.log("CampCountArray");
console.log(campCountArray);
weekCount.campCounts = campCountArray;
);
);
// ****************************************************************
// Check if Week Count with same date already exists.
WeekCount.findOne( dateOfCount: req.body.dateOfCount ).exec(function(
err,
found_weekCount
)
if (err)
console.log("ERROR findone " + err);
return next(err);
if (found_weekCount)
// Week count exists, redirect to its detail page.
console.log("FOUND");
res.redirect(found_weekCount.url);
else
console.log("NOT FOUND");
// weekCount.markModified('campCounts');
weekCount.save(function(err) // <---- does not save
if (err)
console.log("ERROR SAVING: " + err);
return next(err);
console.log("weekCount saved");
console.log(weekCount);
// output below
// Week Count saved. Redirect to week count detail page.
// console.log(weekCount.campCounts);
res.redirect(weekCount.url);
);
);
];
console.log 的输出：
GET /catalog/WeekCount/create 200 219.085 ms - 3782
NOT FOUND <------ count not a duplicate (OK)
CampCountArray
[ count: calf: 1, bull: 0, cow: 0, weaner: 0, ox: 0, heifer: 0 ,
_id: 5d83720e2279011e90a1614b,
campName: 'Bloekom' ,
count: calf: 1, bull: 0, cow: 0, weaner: 0, ox: 0, heifer: 0 ,
_id: 5d83720e2279011e90a1614c,
campName: 'Davel' ,
count: calf: 1, bull: 0, cow: 0, weaner: 0, ox: 0, heifer: 0 ,
_id: 5d83720e2279011e90a1614d,
campName: 'Elfas' ,
count: calf: 1, bull: 0, cow: 0, weaner: 0, ox: 0, heifer: 0 ,
_id: 5d83720e2279011e90a1614e,
campName: 'Groot kamp' ]
weekCount saved
campCounts:
[ count: [Object],
_id: 5d83720e2279011e90a1614b,
campName: 'Bloekom',
__v: 0 ,
count: [Object],
_id: 5d83720e2279011e90a1614c,
campName: 'Davel',
__v: 0 ,
count: [Object],
_id: 5d83720e2279011e90a1614d,
campName: 'Elfas',
__v: 0 ,
count: [Object],
_id: 5d83720e2279011e90a1614e,
campName: 'Groot kamp',
__v: 0 ],
_id: 5d83720e2279011e90a1614a,
dateOfCount: 2019-09-06T00:00:00.000Z,
__v: 0
来自蒙哥：
"_id" : ObjectId("5d83720e2279011e90a1614a"),
"campCounts" : [ ], <---------------------- nothing here!
"dateOfCount" : ISODate("2019-09-06T00:00:00Z"),
"__v" : 0
campCounts 在 mongo 中（示例）：
"_id" : ObjectId("5d83720e2279011e90a1614d"),
"count" :
"calf" : 1,
"bull" : 0,
"cow" : 0,
"weaner" : 0,
"ox" : 0,
"heifer" : 0
,
"campName" : "Elfas",
"__v" : 0
但是 weekCount 没有更新。这就是问题所在。
【问题讨论】：
【参考方案1】：我认为您的怀疑是正确的，即 weekCount 在 CattleClass.find() 回调完成执行之前保存。
您可以使用 .then 语法解决此问题：
CattleClass.find(, "name").exec(function(err, list_cattleClasses)
...
).then( function ()
WeekCount.findOne( dateOfCount: req.body.dateOfCount ).exec(function(
err, found_weekCount)
...
)
你也可以使用 ES6 async/await 语法，但是你的代码需要大量的重写，因为你不能在 await 中使用 .exec()。
这两种方法都将确保 CattleClass.find() 在运行 WeekCount.findOne() 之前完成执行
如果您需要更多信息，有很多关于 Stack Overflow 处理异步代码的精彩帖子。
【讨论】：
我已经能够使用虚拟数据进行保存，所以这就是问题所在。现在重写它。完成后将发布解决方案。感谢您的帮助，不胜感激。【参考方案2】：下面的代码现在可以正常工作了。
使用 .then() 而不是混合回调和承诺。 感谢您的帮助！
exports.weekCount_create_post = [
validator
.body("dateOfCount", "Week Count Data Required")
.toDate()
.isLength( min: 1 )
.trim(),
// Sanitize (escape) the name field.
validator.sanitizeBody("*").escape(),
// Process request after validation and sanitization.
(req, res, next) =>
var weekCountDetail =
dateOfCount: req.body.dateOfCount
;
const errors = validator.validationResult(req);
if (!errors.isEmpty())
// There are errors. Render the form again with sanitized values/error messages.
console.log("ERRORS!s");
async.parallel(
camps: function(callback)
Camp.find()
.sort("name")
.exec(callback);
,
cattleClasses: function(callback)
CattleClass.find(callback);
,
function(err, results)
if (err)
return next(err);
res.render("weekCount_form",
title: "There were Errors! New Week Count",
camps: results.camps,
cattleClasses: results.cattleClasses
);
);
return;
else
Camp.find(, "name")
.exec()
.then(list_camps =>
return CattleClass.find(, "name")
.exec()
.then(list_cattleClasses =>
return [list_camps, list_cattleClasses];
);
)
.then(qResult =>
list_camps = qResult[0];
list_cattleClasses = qResult[1];
var campCountArray = [];
list_camps.forEach(function(campName)
var campCount = new CampCount(
campName: campName.name
);
var emptyCount = true;
list_cattleClasses.forEach(function(cattleClassName)
var tempVar = campName.name + "." + cattleClassName.name;
var tempNum = parseInt(req.body[tempVar]);
if (tempNum)
campCount.count[cattleClassName.name] = req.body[tempVar];
emptyCount = false;
else
campCount.count[cattleClassName.name] = 0;
);
if (!emptyCount)
campCount.save(function(err)
if (err)
return next(err);
);
campCountArray.push(campCount);
);
weekCountDetail.campCounts = campCountArray;
return weekCountDetail;
)
.then(weekCountDetail =>
WeekCount.findOne( dateOfCount: req.body.dateOfCount )
.exec()
.then(found_weekCount =>
if (found_weekCount)
res.redirect(found_weekCount.url);
else
console.log("Not FOUND");
var weekCount = new WeekCount(weekCountDetail);
console.log("WEEKCOUNT3");
console.log(weekCount);
weekCount.save(err =>
if (err)
return next(err);
res.redirect(weekCount.url);
);
)
.catch(err =>
console.log("error findOne " + err);
return next(err);
);
);
];
【讨论】：
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