如何将杂项文档转换为JSON，从而去除嵌入式文档ID，但保留主文档ID？

Question

I have a document that has some embedded documents (and some of those have further embedded documents).

I want to return the document content as JSON but without all the IDs for the embedded documents.

I can do this: mydoc.to_json(:except => :_id) but that strips all BSON IDs, including the one for mydoc.

Is there some other way to only strip the embedded document IDs?

Answer 1

Keep in mind that to_json is actually two steps here:

1. Call as_json to get a Hash.
2. Convert that Hash to a string of JSON.

So you could use as_json instead of to_json to build a Hash without any _id s, then put the _id you care about back in, and finally convert to JSON:

mydoc.as_json(:except => :_id).merge('_id' => mydoc.id).to_json