Shows how a struct holding complex datatypes can be serialized using serde library. Fixed problems with lifetimes.

complex_struct_serialization.rs

#[macro_use]
extern crate serde_derive;

extern crate serde;
extern crate serde_json;

#[derive(Serialize, Debug)]
struct DetailRecord {
    id: i32,
    description: String,
    data: Vec<u8>,
    data_type: String
}
#[derive(Serialize, Debug)]
struct Details <'a>{
    id: i32,
    detail_record_ids: Vec<&'a DetailRecord>
}

#[derive(Serialize, Debug)]
struct Profile <'a>{
    id: i32,
    description: String,
    detail_record_ids: Vec<&'a DetailRecord>,
    profile_specific_records: Vec<&'a ProfileSpecificRecord>
}

#[derive(Serialize, Debug)]
struct ProfileSpecificRecord {
    id: i32,
    description: String,
    data: Vec<u8>,
    data_type: String
}

fn main () {

    //Serialization stuff
    trait ToString where Self: serde::Serialize {
        fn tostring(&self) -> String{
            let serialized = serde_json::to_string(&self).unwrap();
            return serialized;
        }
    }

    impl ToString for DetailRecord {
    }
    impl<'a> ToString for Details<'a> {
    }
    impl ToString for ProfileSpecificRecord {
    }
    impl<'a> ToString for Profile<'a> {
    }

    //Sample data
    let dr1 = DetailRecord { id: 1, description: String::from("name"), data: String::from("Krishna").into_bytes(), data_type: String::from("String")};
    let dr2 = DetailRecord { id: 2, description: String::from("address"), data: String::from("Earth").into_bytes(), data_type: String::from("String")};
    let dr3 = DetailRecord { id: 2, description: String::from("aadhar"), data: String::from("111111111111").into_bytes(), data_type: String::from("String")};

    let d1 = Details {id: 1, detail_record_ids: vec![&dr1, &dr2, &dr3]};

    let ps1 = ProfileSpecificRecord {id: 1, description: String::from("dob"), data: String::from("00/00/1000").into_bytes(), data_type: String::from("date")};
    let p1 = Profile {id:1, description: String::from("aadhar"), detail_record_ids: vec![&dr1, &dr3], profile_specific_records: vec![&ps1]};
    let p1 = Profile {id:2, description: String::from("personal"), detail_record_ids: vec![&dr1, &dr2], profile_specific_records: vec![]};

    println!("p1 string {}",p1.tostring());
    println!("d1 string {}",d1.tostring());
    println!("dr1 string {}",dr1.tostring());
    println!("ps1 string {}",ps1.tostring());

}