I'm trying to deserialize a Spotify metadata JSON from the web API (specifications). I'm using hyper to retrieve the JSON from the server and serde to turn the JSON into something I can actually use within Rust. The JSON is retrieved from the server just fine, but when I try to turn the JSON into an object that can be used Rust panicks and throws an error:
thread '<main>' panicked at 'called 'Result::unwrap()' on an 'Err' value: SyntaxError("expected value", 11, 21)', ../src/libcore/result.rs:746
This is not helpful in the least way, because it doesn't indicate where things go wrong at all. When searching the web I stumbled upon a serde issue, which leads me to think that the problem is related to the nested structure of the JSON.
Can anyone see where things go wrong? Fixing the error would be the best solution for me, but if another crate turns out to be a better solution I'd like to hear that too. I've already tried rustc-serialize, but that crate can't handle the 'type' variables within the json.
The code I use is:
#![feature(custom_derive, plugin)]
#![plugin(serde_macros)]
#![feature(custom_attribute)]
extern crate hyper;
extern crate serde;
extern crate serde_json;
use std::io::Read;
use hyper::Client;
use hyper::header::Connection;
#[derive(Serialize, Deserialize)]
struct Track_Full {
album: Album_Simp,
artists: Vec<Artist_Simp>,
available_markets: Vec<String>,
disc_number: u8,
duration_ms: u32,
explicit: bool,
external_ids: External_IDs,
external_urls: External_URLs,
href: String,
id: String,
name: String,
popularity: u8,
preview_url: String,
track_number: u8,
#[serde(rename="type")]
_type: String,
uri: String
}
#[derive(Serialize, Deserialize)]
struct Album_Simp {
album_type: String,
available_markets: Vec<String>,
external_urls: External_URLs,
href: String,
id: String,
images: Vec<Image>,
name: String,
#[serde(rename="type")]
_type: String,
uri: String
}
#[derive(Serialize, Deserialize)]
struct Artist_Simp {
external_urls: External_URLs,
href: String,
id: String,
name: String,
#[serde(rename="type")]
_type: String,
uri: String
}
#[derive(Serialize, Deserialize)]
struct External_IDs {
isrc: String
}
#[derive(Serialize, Deserialize)]
struct External_URLs {
spotify: String
}
#[derive(Serialize, Deserialize)]
struct Image {
height: u8,
url: String,
width: u8
}
fn main() {
// Create a client.
let mut client = Client::new();
// Creating an outgoing request.
let mut res = client.get("https://api.spotify.com/v1/tracks/0eGsygTp906u18L0Oimnem")
// set a header
.header(Connection::close())
// let 'er go!
.send().unwrap();
// Read the Response.
let mut body = String::new();
res.read_to_string(&mut body).unwrap();
println!("{}", body);
let deserialized: Track_Full = serde_json::from_str(&body).unwrap();
}
The JSON:
{
"album" : {
"album_type" : "album",
"available_markets" : [ "AD", "AR", "AT", "AU", "BE", "BG", "BO", "BR", "CH", "CL", "CO", "CR", "CY", "CZ", "DE", "DK", "DO", "EC", "EE", "ES", "FI", "FR", "GR", "GT", "HK", "HN", "HU", "IE", "IS", "IT", "LI", "LT", "LU", "LV", "MC", "MT", "MY", "NI", "NL", "NO", "NZ", "PA", "PE", "PH", "PL", "PT", "PY", "RO", "SE", "SG", "SI", "SK", "SV", "TR", "TW", "UY" ],
"external_urls" : {
"spotify" : "https://open.spotify.com/album/6TJmQnO44YE5BtTxH8pop1"
},
"href" : "https://api.spotify.com/v1/albums/6TJmQnO44YE5BtTxH8pop1",
"id" : "6TJmQnO44YE5BtTxH8pop1",
"images" : [ {
"height" : 640,
"url" : "https://i.scdn.co/image/8e13218039f81b000553e25522a7f0d7a0600f2e",
"width" : 629
}, {
"height" : 300,
"url" : "https://i.scdn.co/image/8c1e066b5d1045038437d92815d49987f519e44f",
"width" : 295
}, {
"height" : 64,
"url" : "https://i.scdn.co/image/d49268a8fc0768084f4750cf1647709e89a27172",
"width" : 63
} ],
"name" : "Hot Fuss",
"type" : "album",
"uri" : "spotify:album:6TJmQnO44YE5BtTxH8pop1"
},
"artists" : [ {
"external_urls" : {
"spotify" : "https://open.spotify.com/artist/0C0XlULifJtAgn6ZNCW2eu"
},
"href" : "https://api.spotify.com/v1/artists/0C0XlULifJtAgn6ZNCW2eu",
"id" : "0C0XlULifJtAgn6ZNCW2eu",
"name" : "The Killers",
"type" : "artist",
"uri" : "spotify:artist:0C0XlULifJtAgn6ZNCW2eu"
} ],
"available_markets" : [ "AD", "AR", "AT", "AU", "BE", "BG", "BO", "BR", "CH", "CL", "CO", "CR", "CY", "CZ", "DE", "DK", "DO", "EC", "EE", "ES", "FI", "FR", "GR", "GT", "HK", "HN", "HU", "IE", "IS", "IT", "LI", "LT", "LU", "LV", "MC", "MT", "MY", "NI", "NL", "NO", "NZ", "PA", "PE", "PH", "PL", "PT", "PY", "RO", "SE", "SG", "SI", "SK", "SV", "TR", "TW", "UY" ],
"disc_number" : 1,
"duration_ms" : 222075,
"explicit" : false,
"external_ids" : {
"isrc" : "USIR20400274"
},
"external_urls" : {
"spotify" : "https://open.spotify.com/track/0eGsygTp906u18L0Oimnem"
},
"href" : "https://api.spotify.com/v1/tracks/0eGsygTp906u18L0Oimnem",
"id" : "0eGsygTp906u18L0Oimnem",
"name" : "Mr. Brightside",
"popularity" : 74,
"preview_url" : "https://p.scdn.co/mp3-preview/934da7155ec15deb326635d69d050543ecbee2b4",
"track_number" : 2,
"type" : "track",
"uri" : "spotify:track:0eGsygTp906u18L0Oimnem"
}
