TypeError: this.$__setSchema is not a function

[adamreisnz]

Prerequisites

• I have written a descriptive issue title
• I have searched existing issues to ensure the bug has not already been reported

Mongoose version

8.0.2

Node.js version

21.6

MongoDB server version

7.0

Typescript version (if applicable)

n/a

Description

Our error reporting tool captured the following error, which originated from Mongoose and seems to be an internal Mongoose error where the __setSchema function appears to be missing:

Steps to Reproduce

TypeError: this.$__setSchema is not a function
node_modules/mongoose/lib/document.js in Mongoose.Document at line 91:10

  options = Object.assign({}, options);
  // Support `browserDocument.js` syntax
  if (this.$__schema == null) {
    const _schema = utils.isObject(fields) && !fields.instanceOfSchema ?
      new Schema(fields) :
      fields;
    this.$__setSchema(_schema);
    fields = skipId;
    skipId = options;
    options = arguments[4] || {};
  }
  this.$__ = new InternalCache();
node_modules/mongoose/lib/model.js in Mongoose.Model at line 125:12

Don't have exact schema's or an isolated reproducible case at this stage, but if the method has truly been removed or renamed it should be easy to track down.

Expected Behavior

No error to be thrown

[vkarpov15]

The $__setSchema method has not been removed or renamed. The only thing that looks strange from this stack trace is that it looks like you're hitting the "browser document" code path, which is definitely unexpected. Do you have a more complete stack trace?

[adamreisnz]

Hmm, I talked to our developer and he said the only thing he changed was that he was using mongoose.Model('System') instead of mongoose.model('System'), which worked on his local environment apparently but triggered the above error in production.

The issue that caused it is thus resolved, so perhaps it is not worth the time to investigate further, if the method is still there.

[vkarpov15]

@adamreisnz this is more of an error message issue than a bug, calling mongoose.Model('foo') instead of mongoose.model('foo') is an error. We improved that error message in v8.1.1 to be a bit more clear.

[adamreisnz]

Cheers thanks for that