A JSON object is an unordered collection of name-value pairs enclosed in braces. In practical integrations, it carries structured data between Rust, Python, JavaScript, and WebAssembly. section 6.2 section 9.3.2
A Rust program can work with a JSON object through a small sequence:
- Describe the expected fields with a Rust struct, such as String for name and i32 for value. section 6.3
- Derive Deserialize so serde_json::from_str can parse the JSON text into that struct. section 6.3
- Use the resulting values directly, while treating mismatched field types as parsing errors rather than valid data. section 6.3
A small aggregation boundary
A JSON object containing { "name": "Rachelle Ferguson", "value": 948129 } can be parsed into Data, then used to calculate name.length() + value, producing 948146. The same operation can sit behind a Python loop while Rust performs the parsing and calculation. section 6.2 section 6.3
Listing 9.7 lib.rs: Defining the object as a JSON object
#[derive(Default, Debug, Clone, PartialEq, Serialize, Deserialize)]
pub struct Search {
pub term: String,
pub page: isize,
pub limit: isize,
}
A derived Rust struct defines the JSON object exchanged with JavaScript through a WebAssembly binding. section 9.3.2
