本示例代码来源于本人开源项目batata（https://github.com/easynet-cn/batata），致力于实现兼容nacos服务治理平台。
实例代码实现了兼容nacos的JWT Token编码和解码。
主要用到了以下项目：
1：actix-web：https://github.com/actix/actix-web
2：jsonwebtoken：https://github.com/Keats/jsonwebtoken

Nacos JWT Token Payload

#[derive(Debug, Serialize, Deserialize)]
#[serde(rename_all = "camelCase")]
pub struct NacosJwtPayload {
    pub sub: String,
    pub exp: i64,
}

编解码

需要注意Naocs JWT Header中不会写入type

use crate::common::model::{NacosJwtPayload, NacosUser};
use chrono;
use jsonwebtoken::{decode, encode, Algorithm, DecodingKey, EncodingKey, Header, Validation};

pub fn decode_jwt_token(
    token: &str,
    secret_key: &str,
) -> jsonwebtoken::errors::Result<jsonwebtoken::TokenData<crate::service::auth::NacosJwtPayload>> {
    decode::<crate::service::auth::NacosJwtPayload>(
        token,
        &DecodingKey::from_base64_secret(secret_key).unwrap(),
        &Validation::default(),
    )
}

pub fn encode_jwt_token(
    user: &NacosUser,
    secret_key: &str,
    token_expire_seconds: i64,
) -> jsonwebtoken::errors::Result<String> {
    let exp = chrono::Utc::now()
        .checked_add_signed(chrono::Duration::seconds(token_expire_seconds))
        .expect("valid timestamp")
        .timestamp();

    let payload = NacosJwtPayload {
        sub: user.username.clone(),
        exp,
    };

    let header = Header {
        typ: None,
        alg: Algorithm::HS256,
        cty: None,
        jku: None,
        jwk: None,
        kid: None,
        x5u: None,
        x5c: None,
        x5t: None,
        x5t_s256: None,
    };

    encode(
        &header,
        &payload,
        &EncodingKey::from_base64_secret(secret_key).unwrap(),
    )
}