rapblock/src/brainz.rs

use percent_encoding::{utf8_percent_encode, DEFAULT_ENCODE_SET};
use failure::Error;
use std::io::Read;
use std::time::Duration;

#[derive(Serialize, Deserialize, Debug)]
struct MBArtistQueryResult {
    created : String,
    count: i32,
    offset: i32,
    artists: Option<Vec<MBArtist>>,
}

#[derive(Serialize, Deserialize, Debug)]
struct Tag {
    count: i32, // negative doesn't make sense, but it sometimes occurs
    name: String,
}

#[derive(Serialize, Deserialize, Debug)]
struct MBArtist {
    id: String,
    score: i32,
    name: String,
    #[serde(rename="sort-name")]
    sort_name: String,
    tags: Option<Vec<Tag>>
}

lazy_static! {
    static ref BAD_GENRES : Vec<&'static str> = vec![
        "hip hop", "hip-hop", "hiphop", "rnb", "rap", "rapper",
        "hardcore hip hop", "new york hip hop", "east coast hip hop",
        "pop rap"
    ];
}

pub fn artist_sucks(artist : &str) -> Result<bool, Error> {
    let query = utf8_percent_encode(&format!("\"{}\"", artist), DEFAULT_ENCODE_SET).to_string();
    let url = format!("https://musicbrainz.org/ws/2/artist?query={}&fmt=json&inc=tags", query);

    info!("Querying MusicBrainz for artist \"{}\", query URL: {}", artist, url);

    let mut resp = String::new();

    reqwest::Client::builder()
        .timeout(Duration::from_millis(2000))
        .build()?
        .get(&url)
        .header(reqwest::header::USER_AGENT, "Bad Spotify Song Skipper/0.0.1 ( ondra@ondrovo.com )")
        .header(reqwest::header::ACCEPT, "text/json")
        .send()?
        .read_to_string(&mut resp)?;

    debug!("Resp: {}", resp);

    let result : MBArtistQueryResult = serde_json::from_str(&resp)?;

    info!("Response OK");
    debug!("{:#?}", result);

    if result.count == 0 {
        // not found, let's hope it's OK
        warn!("No results!");
        return Err(failure::err_msg("Artist not found"));
    } else {
        info!("Got {} results", result.count);
        let artists = result.artists.as_ref().unwrap();
        if artists[0].tags.is_some() {
            let tags = artists[0].tags.as_ref().unwrap();
            let as_vec : Vec<&String> = tags.iter().map(|t| &t.name).collect();
            debug!("First artist has tags: {:?}", tags);
            for tag in as_vec {
                if BAD_GENRES.contains(&tag.as_str()) {
                    info!("Found a bad tag: {}", tag);
                    return Ok(true);
                }
            }
            info!("All tags OK");
            return Ok(false);
        } else {
            warn!("No tags, can't determine genre");
            return Err(failure::err_msg("Artist found, but has no tags"));
        }
    }
}