Generate pretty (indented) JSON with serde
The serde_json::to_string_pretty function generates pretty-printed indented JSON.
#[macro_use]extern crate serde_json;fn main() { let obj = json!({"foo":1,"bar":2}); println!("{}", serde_json::to_string_pretty(&obj).unwrap());}This approach defaults to 2 spaces of indentation, which happens to be what you asked for in your question. You can customize the indentation by using PrettyFormatter::with_indent.
#[macro_use]extern crate serde_json;extern crate serde;use serde::Serialize;fn main() { let obj = json!({"foo":1,"bar":2}); let buf = Vec::new(); let formatter = serde_json::ser::PrettyFormatter::with_indent(b" "); let mut ser = serde_json::Serializer::with_formatter(buf, formatter); obj.serialize(&mut ser).unwrap(); println!("{}", String::from_utf8(ser.into_inner()).unwrap());}