Struct CookieStore 

pub struct CookieStore { /* private fields */ }

Keeps the whole session in the cookie, signed with HMAC-SHA256 so a client cannot edit it.

No server-side state, which makes it the simplest thing that works. Two properties are worth being explicit about:

• Signed, not encrypted. The values are readable by whoever holds the cookie. Do not put anything in it the visitor should not see.
• The contents travel on every request. This suits a user id and a flash message, not a shopping cart.
• Expiry is carried inside the signature. Set-Cookie’s Max-Age is only a hint to a well-behaved client; a copied cookie ignores it. When the session plugin sets a max age, the deadline is signed into the payload and checked on load, so a captured cookie stops working.
• There is still no revocation. Logging out clears the client’s copy, but a copy taken beforehand stays valid until its deadline, because nothing server-side records that it was withdrawn. A store backed by server state is what fixes that.

Use a key with at least 32 bytes of entropy, and keep it out of source control.

Implementations

impl CookieStore

pub fn new(key: impl Into<Vec<u8>>) -> Self

Build a store from a signing key.

pub fn with_max_age(self, secs: i64) -> Self

Sign an expiry secs in the future into every cookie this store issues.

Set by Sessions::max_age; without it a cookie is valid for as long as the signing key is.

Trait Implementations

impl SessionStore for CookieStore

fn store<'life0, 'life1, 'life2, 'async_trait>( &'life0 self, data: &'life1 BTreeMap<String, String>, _previous: Option<&'life2 str>, ) -> Pin<Box<dyn Future<Output = Result<Option<String>>> + Send + 'async_trait>>

where Self: 'async_trait, 'life0: 'async_trait, 'life1: 'async_trait, 'life2: 'async_trait,

previous is unused: the whole session lives in the cookie, so there is no server-side record to withdraw. Nothing here can fail either, for the same reason — signing a payload asks nothing of anybody — so this never returns Err, and an emptied session simply re-signs an empty payload.

fn with_session_max_age(&self, secs: i64) -> Option<Box<dyn SessionStore>>

Adopt the session lifetime configured on Sessions::max_age.

fn load<'life0, 'life1, 'async_trait>( &'life0 self, raw: &'life1 str, ) -> Pin<Box<dyn Future<Output = Option<BTreeMap<String, String>>> + Send + 'async_trait>>

where Self: 'async_trait, 'life0: 'async_trait, 'life1: 'async_trait,

Recover a session from the cookie value, if it is intact.