How to track fields changes at update?

[gugadev]

I have a User schema with a path email. I want track changes over this field, so, when the user changes his email, a job is executed. Which is the way to do it with mongoose, since the update hooks pass a Query instead a Document (can't use isModified(path))?

[gugadev]

Actually, instead of use Model.update, I follow this pattern:

• Fetch the model to update via ID
• Assign manually the new values (user.email = data.email || user.email)
• Use save method.

So, with this way I'm able to get the document inside the pre save hook and I can check if the path was changed via doc.isModified('email').

Would be great if docs are availabe on update and remove hooks too. It is possible?

[vkarpov15]

You can access getUpdate() in a pre update hook to check whether email is getting updated or not:

mySchema.pre('update', function() {
  if (this.getUpdate().email) {
    // Run job
  }
});

You can't use isModified(), but email won't change unless email is in the update