Serializing a BSON document to a simple JSON

[erfanium]

I wonder is there any way to serialize a bson document to a simple json (not extjson)?
I know there's two similar methods Bson::into_relaxed_extjson and Bson::into_canonical_extjson but they convert them into extjson, not simple json, which i don't want.

Here's is an example of my expected result.

let doc = bson!({ "x": 5i32, "_id": oid::ObjectId::new(), "d": bson::DateTime::now() });


let simple_json = doc.clone().into_simple_json();
println!("{}", simple_json); // { "x": 5, "_id": <hexstring>, "d": "2020-06-01T22:19:13.075Z" }

This is exactly the same behavior of JSON.stringify(bson_document) in JavaScript

[kmahar]

Hi @erfanium, thanks for reaching out.

There isn't a way to do this directly from a Bson right now.

We recently discussed doing something that might help in this case: RUST-1178. See #191 for some related discussion. What that ticket proposes is adding a way to opt into having the driver produce "plain" JSON for types such as bson::DateTime and oid::ObjectId.

One workaround currently available would be to define a type modeling your data that implements Serialize and Deserialize. You could then deserialize your BSON data into that type, and serialize the type into plain JSON. See here for some details on how to do that.
Beyond that, another option would be to implement your own logic, something like this, that serializes BSON types the way you want them to be represented.

[erfanium]

Thank you @kmahar

another option would be to implement your own logic, something like this

I wanna add that it's not really my own logic, MongoDB Atlas Data Api uses this logic for response bodies, so I think it's necessary to have simple-json serialization in official bson libs.
https://www.mongodb.com/docs/atlas/api/data-api-resources/#find-a-single-document

[kmahar]

@erfanium Atlas Data API supports both plain and extended JSON, with the caveat that the plain format can lead to data loss because not all BSON types are representable in plain JSON (see docs).
An additional caveat worth noting is that even for types that can be represented in plain JSON, it is impossible for many of them to be losslessly round-tripped from Document -> JSON -> Document. For example, the "plain" JSON of an ObjectId is a string, and so if you have a document like doc! { "_id": oid::ObjectId::new() }, serialize it to plain JSON, and then deserialize the JSON back into a Document, the BSON library cannot tell that the field was initially an ObjectId, and so it will be decoded as a string instead: doc! { "_id": "string_representation_here" }.

Due to these limitations, we've chosen not to support plain JSON in this library at this time. If you want to use this BSON library with Atlas Data API I would strongly recommend having your endpoints return and accept extended JSON, as it will ensure you do not lose any data or inadvertently change the data type of any fields in your documents.

[erfanium]

@kmahar

Atlas Data API supports both plain and extended JSON, with the caveat that the plain format can lead to data loss because not all BSON types are representable in plain JSON (see docs).

That was all I need, Thank you!

[DanieliusDev]

I would like to quickly bring this back and ask: since we cannot make both JSON and BSON with one struct, is there really a point of using bson features like uuids and dates instead of just strings?

[erfanium]

@gamertike databases can perform more optimizations when they know a field is a UUID, or Date
also it helps data integrity