Error convert string Json to Document using Serde.

[almir-lima]

Hi everyone, i try convert a String JSON to Document, but i receive a error when key value is a Integer, if i put in quotes number then it's work.

it's work:
let d: Document = serde_json::from_str( &"{ "id" : "1" }".to_string() ).unwrap();

Don't work:
let d: Document = serde_json::from_str( &"{ "id" : 1 }".to_string() ).unwrap();

I receive this message below:

thread '' panicked at 'called Result::unwrap() on an Err value: Error("invalid type: integer 1, expected a signed integer", line: 1, column: 10)'
note: run with RUST_BACKTRACE=1 environment variable to display a backtrace

[saghm]

To convert raw JSON into a Document, you'll need to first create a serde_json::Map, and then convert that into a Document:

use bson::Document;
use serde_json::{Map, Value};

let value: Map<String, Value> = serde_json::from_str("{ \"id\": 1 }")?;
let document = Document::try_from(value)?;

For an arbitrary BSON value, you can substitute Map and Document with Value and Bson:

use bson::Bson;
use serde_json::Value;

let value: Value = serde_json::from_str("1")?;
let bson_value = Bson::try_from(value)?;

Alternately, if you're using a custom type with Serialize and Deserialize to model your data, you can use that as an intermediate form between the JSON and BSON to validate the structure:

use bson::Bson;
use serde::{Deserialize, Serialize};
use serde_json::Value;

#[derive(Deserialize, Serialize)]
struct Item {
    id: i32,
}

let item: Item = serde_json::from_str("{ \"id\": 1 }")?;
let bson_value = bson::ser::to_bson(&item)?;

[patrickfreed]

I filed RUST-507 to track work for deserializing BSON types like this easier. Thank you for filing this issue!

[njust]

Hi, I'm trying to convert a raw json to a bson document as described above. Unfortunatelty the Document::try_from method is not public anymore, so I tried

    let value: Map<String, Value> = serde_json::from_str("{ \"id\": 1 }")?;
    let document = bson::to_document(&value)?;

this compiles, but gives me a error at runtime: Error: UnsupportedUnsignedType. My dependencies are:

#bson = {git = "https://github.com/mongodb/bson-rust.git"}
bson = "1.1.0"
serde = "1.0.117"
serde_json = "1.0.59"

[isabelatkinson]

Hi @njust!

We currently have work in progress to deserialize unsigned integers which will be included in the next release. You can take a look at RUST-507 to track this work. In the meantime, the following code should give you the desired document:

let value: Map<String, Value> = serde_json::from_str("{ \"id\": 1 }")?;
let doc = Document::try_from(value)?;

In order to use Document::try_from, make sure you have std::convert::TryFrom included in your imports.

[njust]

Hi @isabelatkinson, thanks for helping out.

[isabelatkinson]

Hi @njust, the work for RUST-507 to convert from unsigned to signed automatically during deserialization has been completed and will be included in the next release.