Add logout support.

1 files changed, 69 insertions, 0 deletions

diff --git a/src/login/extract.rs b/src/login/extract.rs
new file mode 100644
index 0000000..d39e3df
--- /dev/null
+++ b/src/login/extract.rs
@@ -0,0 +1,69 @@
+use std::convert::Infallible;
+
+use axum::{
+    extract::FromRequestParts,
+    http::request::Parts,
+    response::{IntoResponseParts, ResponseParts},
+};
+use axum_extra::extract::cookie::{Cookie, CookieJar};
+
+// The usage pattern here - receive the extractor as an argument, return it in
+// the response - is heavily modelled after CookieJar's own intended usage.
+pub struct IdentityToken {
+    cookies: CookieJar,
+}
+
+impl IdentityToken {
+    /// Get the identity token sent in the request, if any. If the identity was
+    /// not sent, or if it has previously been [clear]ed, then this will return
+    /// [None]. If the identity has previously been [set], then this will return
+    /// that token.
+    pub fn token(&self) -> Option<&str> {
+        self.cookies.get(IDENTITY_COOKIE).map(Cookie::value)
+    }
+
+    /// Positively set the identity token, and ensure that it will be sent back
+    /// to the client when this extractor is included in a response.
+    pub fn set(self, token: &str) -> Self {
+        let identity_cookie = Cookie::build((IDENTITY_COOKIE, String::from(token)))
+            .http_only(true)
+            .permanent()
+            .build();
+
+        IdentityToken {
+            cookies: self.cookies.add(identity_cookie),
+        }
+    }
+
+    /// Remove the identity token and ensure that it will be cleared when this
+    /// extractor is included in a response.
+    pub fn clear(self) -> Self {
+        IdentityToken {
+            cookies: self.cookies.remove(IDENTITY_COOKIE),
+        }
+    }
+}
+
+const IDENTITY_COOKIE: &str = "identity";
+
+#[async_trait::async_trait]
+impl<S> FromRequestParts<S> for IdentityToken
+where
+    S: Send + Sync,
+{
+    type Rejection = Infallible;
+
+    async fn from_request_parts(parts: &mut Parts, state: &S) -> Result<Self, Self::Rejection> {
+        let cookies = CookieJar::from_request_parts(parts, state).await?;
+        Ok(IdentityToken { cookies })
+    }
+}
+
+impl IntoResponseParts for IdentityToken {
+    type Error = Infallible;
+
+    fn into_response_parts(self, res: ResponseParts) -> Result<ResponseParts, Self::Error> {
+        let IdentityToken { cookies } = self;
+        cookies.into_response_parts(res)
+    }
+}