Retry auth automatically, remove tower dep

kordophone/Cargo.toml

@@ -7,6 +7,8 @@ edition = "2021"
 
 [dependencies]
 async-trait = "0.1.80"
+base64 = "0.22.1"
+chrono = "0.4.38"
 ctor = "0.2.8"
 hyper = { version = "0.14", features = ["full"] }
 hyper-tls = "0.5.0"
@@ -17,7 +19,4 @@ serde_json = "1.0.91"
 serde_plain = "1.0.2"
 time = { version = "0.3.17", features = ["parsing", "serde"] }
 tokio = { version = "1.37.0", features = ["full"] }
-tower = "0.4.13"
-tower-http = { version = "0.5.2", features = ["trace"] }
-tower-hyper = "0.1.1"
 uuid = { version = "1.6.1", features = ["v4", "fast-rng", "macro-diagnostics"] }

kordophone/src/api/http_client.rs

@@ -1,24 +1,31 @@
 extern crate hyper;
 extern crate serde;
 
-use std::{path::PathBuf, str};
+use std::{borrow::Cow, default, path::PathBuf, str};
 use log::{error};
 
-use hyper::{Body, Client, Method, Request, Uri};
-use tower::{ServiceBuilder};
+use hyper::{client::ResponseFuture, Body, Client, Method, Request, Uri};
 
 use async_trait::async_trait;
-use serde::de::DeserializeOwned;
+use serde::{de::DeserializeOwned, Deserialize, Serialize};
 
-use crate::{APIInterface, model::Conversation};
+use crate::{model::{Conversation, JwtToken}, APIInterface};
 
 type HttpClient = Client<hyper::client::HttpConnector>;
 
-pub struct HTTPClient {
+pub struct HTTPAPIClient {
     pub base_url: Uri,
+    credentials: Option<Credentials>,
+    auth_token: Option<JwtToken>,
     client: HttpClient,
 }
 
+#[derive(Clone, Serialize, Deserialize, Debug)]
+pub struct Credentials {
+    pub username: String,
+    pub password: String,
+}
+
 #[derive(Debug)]
 pub enum Error {
     ClientError(String),
@@ -39,29 +46,65 @@ impl From <serde_json::Error> for Error {
     }
 }
 
+trait AuthBuilder {
+    fn with_auth(self, token: &Option<JwtToken>) -> Self;
+}
+
+impl AuthBuilder for hyper::http::request::Builder {
+    fn with_auth(self, token: &Option<JwtToken>) -> Self {
+        if let Some(token) = &token {
+            self.header("Authorization", token.to_header_value())
+        } else { self }
+    }
+}
+
+trait AuthSetting {
+    fn authenticate(&mut self, token: &Option<JwtToken>);
+}
+
+impl<B> AuthSetting for hyper::http::Request<B> {
+    fn authenticate(&mut self, token: &Option<JwtToken>) {
+        if let Some(token) = &token {
+            self.headers_mut().insert("Authorization", token.to_header_value());
+        }
+    }
+}
+
 #[async_trait]
-impl APIInterface for HTTPClient {
+impl APIInterface for HTTPAPIClient {
     type Error = Error;
 
-    async fn get_version(&self) -> Result<String, Self::Error> {
+    async fn get_version(&mut self) -> Result<String, Self::Error> {
         let version: String = self.request("/version", Method::GET).await?;
         Ok(version)
     }
 
-    async fn get_conversations(&self) -> Result<Vec<Conversation>, Self::Error> {
+    async fn get_conversations(&mut self) -> Result<Vec<Conversation>, Self::Error> {
         let conversations: Vec<Conversation> = self.request("/conversations", Method::GET).await?;
         Ok(conversations)
     }
+
+    async fn authenticate(&mut self, credentials: Credentials) -> Result<JwtToken, Self::Error> {
+        #[derive(Deserialize, Debug)]
+        struct AuthResponse {
+            jwt: String,
+        }
+
+        let body = || -> Body { serde_json::to_string(&credentials).unwrap().into() };
+        let token: AuthResponse = self.request_with_body_retry("/authenticate", Method::POST, body, false).await?;
+        let token = JwtToken::new(&token.jwt).map_err(|_| Error::DecodeError)?;
+        self.auth_token = Some(token.clone());
+        Ok(token)
+    }
 }
 
-impl HTTPClient {
-    pub fn new(base_url: Uri) -> HTTPClient {
-        let client = ServiceBuilder::new()
-            .service(Client::new());
-
-        HTTPClient { 
-            base_url,
-            client, 
+impl HTTPAPIClient {
+    pub fn new(base_url: Uri, credentials: Option<Credentials>) -> HTTPAPIClient {
+        HTTPAPIClient { 
+            base_url: base_url,
+            credentials: credentials,
+            auth_token: Option::None,
+            client: Client::new(),
         }
     }
 
@@ -74,29 +117,67 @@ impl HTTPClient {
         Uri::try_from(parts).unwrap()
     }
 
-    async fn request<T: DeserializeOwned>(&self, endpoint: &str, method: Method) -> Result<T, Error> {
-        self.request_with_body(endpoint, method, Body::empty()).await
+    async fn request<T: DeserializeOwned>(&mut self, endpoint: &str, method: Method) -> Result<T, Error> {
+        self.request_with_body(endpoint, method, || { Body::empty() }).await
     }
 
-    async fn request_with_body<T: DeserializeOwned>(&self, endpoint: &str, method: Method, body: Body) -> Result<T, Error> {
+    async fn request_with_body<T, B>(&mut self, endpoint: &str, method: Method, body_fn: B) -> Result<T, Error> 
+        where T: DeserializeOwned, B: Fn() -> Body 
+    {
+        self.request_with_body_retry(endpoint, method, body_fn, true).await
+    }
+
+    async fn request_with_body_retry<T, B>(
+        &mut self, 
+        endpoint: &str, 
+        method: Method, 
+        body_fn: B, 
+        retry_auth: bool) -> Result<T, Error>
+    where 
+        T: DeserializeOwned, 
+        B: Fn() -> Body
+    {
+        use hyper::StatusCode;
+
         let uri = self.uri_for_endpoint(endpoint);
-        let request = Request::builder()
-            .method(method)
-            .uri(uri)
-            .body(body)
-            .unwrap();
+        let build_request = move |auth: &Option<JwtToken>| {
+            let body = body_fn();
+            Request::builder()
+                .method(&method)
+                .uri(&uri)
+                .with_auth(auth)
+                .body(body)
+                .expect("Unable to build request")
+        };
 
-        let future = self.client.request(request);
-        let res = future.await?;
-        let status = res.status();
+        let request = build_request(&self.auth_token);
+        let mut response = self.client.request(request).await?;
+        match response.status() {
+            StatusCode::OK => { /* cool */ },
 
-        if status != hyper::StatusCode::OK {
-            let message = format!("Request failed ({:})", status);
-            return Err(Error::ClientError(message));
+            // 401: Unauthorized. Token may have expired or is invalid. Attempt to renew. 
+            StatusCode::UNAUTHORIZED => {
+                if !retry_auth {
+                    return Err(Error::ClientError("Unauthorized".into()));
+                }
+
+                if let Some(credentials) = &self.credentials {
+                    self.authenticate(credentials.clone()).await?;
+
+                    let request = build_request(&self.auth_token);
+                    response = self.client.request(request).await?;
+                }
+            },
+
+            // Other errors: bubble up. 
+            _ => {
+                let message = format!("Request failed ({:})", response.status());
+                return Err(Error::ClientError(message));    
+            }
         }
 
         // Read and parse response body
-        let body = hyper::body::to_bytes(res.into_body()).await?;
+        let body = hyper::body::to_bytes(response.into_body()).await?;
         let parsed: T = match serde_json::from_slice(&body) {
             Ok(result) => Ok(result),
             Err(json_err) => {
@@ -121,13 +202,18 @@ mod test {
         log::set_max_level(log::LevelFilter::Trace);
     }
 
-    fn local_mock_client() -> HTTPClient {
+    fn local_mock_client() -> HTTPAPIClient {
         let base_url = "http://localhost:5738".parse().unwrap();
-        HTTPClient::new(base_url)
+        let credentials = Credentials { 
+            username: "test".to_string(),
+            password: "test".to_string(),
+        };
+
+        HTTPAPIClient::new(base_url, credentials.into())
     }
 
     async fn mock_client_is_reachable() -> bool {
-        let client = local_mock_client();
+        let mut client = local_mock_client();
         let version = client.get_version().await;
 
         match version {
@@ -146,7 +232,7 @@ mod test {
             return;
         }
 
-        let client = local_mock_client();
+        let mut client = local_mock_client();
         let version = client.get_version().await.unwrap();
         assert!(version.starts_with("KordophoneMock-"));
     }
@@ -158,7 +244,7 @@ mod test {
             return;
         }
 
-        let client = local_mock_client();
+        let mut client = local_mock_client();
         let conversations = client.get_conversations().await.unwrap();
         assert!(!conversations.is_empty());
     }

kordophone/src/api/mod.rs

@@ -1,17 +1,23 @@
 use async_trait::async_trait;
 pub use crate::model::Conversation;
+use crate::model::JwtToken;
 
 pub mod http_client;
-pub use http_client::HTTPClient;
+pub use http_client::HTTPAPIClient;
+
+use self::http_client::Credentials;
 
 #[async_trait]
 pub trait APIInterface {
     type Error;
 
     // (GET) /version
-    async fn get_version(&self) -> Result<String, Self::Error>;
+    async fn get_version(&mut self) -> Result<String, Self::Error>;
     
     // (GET) /conversations
-    async fn get_conversations(&self) -> Result<Vec<Conversation>, Self::Error>;
+    async fn get_conversations(&mut self) -> Result<Vec<Conversation>, Self::Error>;
+
+    // (POST) /authenticate
+    async fn authenticate(&mut self, credentials: Credentials) -> Result<JwtToken, Self::Error>;
 }
 

kordophone/src/model/jwt.rs

@@ -0,0 +1,112 @@
+use std::error::Error;
+
+use base64::{
+    engine::{self, general_purpose},
+    Engine,
+};
+
+use chrono::{DateTime, Utc};
+use hyper::http::HeaderValue;
+use serde::Deserialize;
+
+#[derive(Deserialize, Debug, Clone)]
+struct JwtHeader {
+    alg: String,
+    typ: String,
+}
+
+#[derive(Deserialize, Debug, Clone)]
+enum ExpValue {
+    Integer(i64),
+    String(String),
+}
+
+#[derive(Deserialize, Debug, Clone)]
+struct JwtPayload {
+    exp: serde_json::Value,
+    iss: Option<String>,
+    user: Option<String>,
+}
+
+#[derive(Debug, Clone)]
+pub struct JwtToken {
+    header: JwtHeader,
+    payload: JwtPayload,
+    signature: Vec<u8>,
+    expiration_date: DateTime<Utc>,
+    token: String,
+}
+
+impl JwtToken {
+    fn decode_token_using_engine(
+        token: &str,
+        engine: engine::GeneralPurpose,
+    ) -> Result<Self, Box<dyn Error + Send + Sync>> {
+        let mut parts = token.split('.');
+        let header = parts.next().unwrap();
+        let payload = parts.next().unwrap();
+        let signature = parts.next().unwrap();
+
+        let header = engine.decode(header)?;
+        let payload = engine.decode(payload)?;
+        let signature = engine.decode(signature)?;
+
+        // Parse jwt header
+        let header: JwtHeader = serde_json::from_slice(&header)?;
+
+        // Parse jwt payload
+        let payload: JwtPayload = serde_json::from_slice(&payload)?;
+
+        // Parse jwt expiration date
+        // Annoyingly, because of my own fault, this could be either an integer or string.
+        let exp: i64 = payload.exp.as_i64().unwrap_or_else(|| {
+            let exp: String = payload.exp.as_str().unwrap().to_string();
+            exp.parse().unwrap()
+        });
+
+        let timestamp = chrono::NaiveDateTime::from_timestamp_opt(exp, 0).unwrap();
+        let expiration_date = DateTime::<Utc>::from_utc(timestamp, Utc);
+
+        Ok(JwtToken {
+            header,
+            payload,
+            signature,
+            expiration_date,
+            token: token.to_string(),
+        })
+    }
+
+    pub fn new(token: &str) -> Result<Self, Box<dyn Error + Send + Sync>> {
+        // STUPID: My mock server uses a different encoding than the real server, so we have to
+        // try both encodings here.
+
+        Self::decode_token_using_engine(token, general_purpose::STANDARD).or(
+            Self::decode_token_using_engine(token, general_purpose::URL_SAFE_NO_PAD),
+        )
+    }
+
+    pub fn dummy() -> Self {
+        JwtToken {
+            header: JwtHeader {
+                alg: "none".to_string(),
+                typ: "JWT".to_string(),
+            },
+            payload: JwtPayload {
+                exp: serde_json::Value::Null,
+                iss: None,
+                user: None,
+            },
+            signature: vec![],
+            expiration_date: Utc::now(),
+            token: "".to_string(),
+        }
+    }
+
+    pub fn is_valid(&self) -> bool {
+        self.expiration_date > Utc::now()
+    }
+
+    pub fn to_header_value(&self) -> HeaderValue {
+        format!("Bearer {}", self.token).parse().unwrap()
+    }
+}

kordophone/src/model/mod.rs

@@ -1,3 +1,5 @@
-
 pub mod conversation;
 pub use conversation::Conversation;
+
+pub mod jwt;
+pub use jwt::JwtToken;

kordophone/src/tests/mod.rs

@@ -9,7 +9,7 @@ pub mod api_interface {
     
     #[tokio::test]
     async fn test_version() {
-        let client = TestClient::new();
+        let mut client = TestClient::new();
         let version = client.get_version().await.unwrap();
         assert_eq!(version, client.version);
     }

kordophone/src/tests/test_client.rs

@@ -1,7 +1,7 @@
 use async_trait::async_trait;
 
 pub use crate::APIInterface;
-use crate::model::Conversation;
+use crate::{api::http_client::Credentials, model::{Conversation, JwtToken}};
 
 pub struct TestClient {
     pub version: &'static str,
@@ -24,11 +24,15 @@ impl TestClient {
 impl APIInterface for TestClient {
     type Error = TestError;
 
-    async fn get_version(&self) -> Result<String, Self::Error> {
+    async fn authenticate(&mut self, credentials: Credentials) -> Result<JwtToken, Self::Error> {
+        Ok(JwtToken::dummy())
+    }
+
+    async fn get_version(&mut self) -> Result<String, Self::Error> {
         Ok(self.version.to_string())
     }
 
-    async fn get_conversations(&self) -> Result<Vec<Conversation>, Self::Error> {
+    async fn get_conversations(&mut self) -> Result<Vec<Conversation>, Self::Error> {
         Ok(self.conversations.clone())
     }
 }