如何生成唯一的哈希并将其保存在我的 MongoDB 文档中，而不必通过 req.body 发送？

Posted 2023-03-11

【中文标题】如何生成唯一的哈希并将其保存在我的 MongoDB 文档中，而不必通过 req.body 发送？

【英文标题】：How can I generate a unique hash and save it in my MongoDB document without it having to be sent via req.body?

【发布时间】：2020-08-19 12:49:46

【问题描述】：

如何生成唯一的哈希并将其保存在我的 Mongoose 文档中的键下，而不需要用户输入任何内容？我知道我可以取出必需的，但同时我想保持它是必需的，所以它总是存在的。这是我的代码：

模型/user.js

let ChannelSchema = new Schema(
  provider: type: String,
  stream_key: type: String,
  auth: 
    access_token: type: String,
    refresh_token: type: String,
  ,
  profile: 
    id: String,
    login: String
  ,
,  timestamps: true )

let UserSchema = new Schema(
  name: type: String, required: true, unique: true,
  email: type: String, required: true, unique: true,
  password: type: String, required: true, select: false,
  stream_key: type: String, required: true ,
  channel: [ ChannelSchema ]
);

let createStreamKey = (next) => 
  let user = this;
  if(!user.isNew('stream_key')) 
    return next();
  
  const id = crypto.randomBytes(20).toString('hex');
  user.stream_key = `sinuous_$id`;
  next();


UserSchema.pre('save', createStreamKey);

错误

Error [ValidationError]: User validation failed: stream_key: Path `stream_key` is required.
    at ValidationError.inspect (C:\Users\Who\WebstormProject\what\node_modules\mongoose\lib\error\validation.js:61:24)
    at formatValue (internal/util/inspect.js:563:31)
    at inspect (internal/util/inspect.js:221:10)
    at formatWithOptions (internal/util/inspect.js:1693:40)
    at Object.Console.<computed> (internal/console/constructor.js:272:10)
    at Object.log (internal/console/constructor.js:282:61)
    at C:\Users\Who\WebstormProject\what\routes\auth.js:23:15
    at processTicksAndRejections (internal/process/task_queues.js:93:5) 
  errors: 
    stream_key: MongooseError [ValidatorError]: Path `stream_key` is required.

【参考方案1】：

您在createStreamKey 函数中使用了this 关键字，但这是一个箭头函数，那么this 关键字将无法按您的预期工作。

将其更改为“普通”函数语法（函数表达式），例如：

const createStreamKey = function(next) 
  let user = this;
  if (!user.isNew('stream_key')) 
    return next();
  
  const id = crypto.randomBytes(20).toString('hex');
  user.stream_key = `sinuous_$id`;
  next();