Struct Modified 

pub struct Modified { /* private fields */ }

A handler for the Last-Modified and If-Modified-Since header interaction.

This handler does not set a Last-Modified header on its own, but relies on other handlers doing so.

Precedence: If-None-Match wins

If-Modified-Since is evaluated only when the request carries no If-None-Match. Per RFC 9110 §13.1.3:

A recipient MUST ignore If-Modified-Since if the request contains an If-None-Match header field; the condition in If-None-Match is considered to be a more accurate replacement for the condition in If-Modified-Since, and the two are only combined for the sake of interoperating with older intermediaries that might not implement If-None-Match.

This matters most in the case it is easiest to overlook: when the entity tag did not match. Honoring both conditions would let a coarse timestamp comparison override an Etag that had already determined the representation changed, answering 304 for a body that is genuinely new. Browsers routinely replay both headers, so any handler whose Last-Modified is coarser than its entity tag — a rendered response whose inputs are versioned rather than timestamped, say — would otherwise serve stale content.

Implementations

impl Modified

pub fn new() -> Self

constructs a new Modified handler

Trait Implementations

impl Clone for Modified

fn clone(&self) -> Modified

Returns a duplicate of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Copy for Modified

impl Debug for Modified

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl Default for Modified

fn default() -> Modified

Returns the “default value” for a type.

impl Handler for Modified

async fn before_send(&self, conn: Conn) -> Conn

Performs any final modifications to this conn after all handlers have been run. Although this is a slight deviation from the simple conn->conn->conn chain represented by most Handlers, it provides an easy way for libraries to effectively inject a second handler into a response chain. This is useful for loggers that need to record information both before and after other handlers have run, as well as database transaction handlers and similar library code.

async fn run(&self, conn: Conn) -> Conn

Executes this handler, performing any modifications to the Conn that are desired.

fn init(&mut self, info: &mut Info) -> impl Future<Output = ()> + Send

Performs one-time async set up on a mutable borrow of the Handler before the server starts accepting requests. This allows a Handler to be defined in synchronous code but perform async setup such as establishing a database connection or fetching some state from an external source. This is optional, and chances are high that you do not need this.

fn has_upgrade(&self, upgrade: &Upgrade) -> bool

predicate function answering the question of whether this Handler would like to take ownership of the negotiated Upgrade. If this returns true, you must implement Handler::upgrade. The first handler that responds true to this will receive ownership of the trillium::Upgrade in a subsequent call to Handler::upgrade

fn upgrade(&self, upgrade: Upgrade) -> impl Future<Output = ()> + Send

This will only be called if the handler reponds true to Handler::has_upgrade and will only be called once for this upgrade. There is no return value, and this function takes exclusive ownership of the underlying transport once this is called. You can downcast the transport to whatever the source transport type is and perform any non-http protocol communication that has been negotiated. You probably don’t want this unless you’re implementing something like websockets. Please note that for many transports such as TcpStreams, dropping the transport (and therefore the Upgrade) will hang up / disconnect.

fn name(&self) -> Cow<'static, str>

Customize the name of your handler. This is used in Debug implementations. The default is the type name of this handler.