How to compute a JWK thumbprint (RFC 7638) in Rust

1[dependencies]
2jsonwebtoken = { version = "=11.1.0", features = ["rust_crypto"] }
3serde_json = "=1.0.154"

1use jsonwebtoken::jwk::{Jwk, ThumbprintHash};
2use jsonwebtoken::DecodingKey;
3 
4fn main() -> Result<(), Box<dyn std::error::Error>> {
5    // From a JWK: Jwk::thumbprint implements RFC 7638 (kid, use and alg are ignored)
6    for file in ["ec.jwk.json", "rsa.jwk.json", "okp.jwk.json"] {
7        let jwk: Jwk = serde_json::from_str(&std::fs::read_to_string(file)?)?;
8        println!("{file}: {}", jwk.thumbprint(ThumbprintHash::SHA256)?);
9    }
10 
11    // From a PEM public key: DecodingKey -> Jwk -> thumbprint
12    let pems: [(&str, fn(&[u8]) -> jsonwebtoken::errors::Result<DecodingKey>); 3] = [
13        ("ec.pub.pem", DecodingKey::from_ec_pem),
14        ("rsa.pub.pem", DecodingKey::from_rsa_pem),
15        ("okp.pub.pem", DecodingKey::from_ed_pem),
16    ];
17    for (file, parse) in pems {
18        let jwk = Jwk::from_decoding_key(&parse(&std::fs::read(file)?)?, None)?;
19        println!("{file}: {}", jwk.thumbprint(ThumbprintHash::SHA256)?);
20    }
21    Ok(())
22}