feat: Add from_bytes/u8_bytes to dev::Payload

This allows convinent construction of Payload from bytes which is
useful in middlewares

closes actix/actix-web#3589

Add doc comment and changelog entry

actix-http/CHANGES.md

@@ -6,6 +6,7 @@
 
 - Add `header::CLEAR_SITE_DATA` constant.
 - Add `Extensions::get_or_insert[_with]()` methods.
+- Add `dev::Payload::from_[bytes/u8_bytes]()` methods.
 
 ### Changed
 

actix-http/src/payload.rs

@@ -69,6 +69,21 @@ impl From<BoxedPayloadStream> for Payload {
 }
 
 impl<S> Payload<S> {
+    /// Create Payload from bytes::Bytes
+    pub fn from_bytes(bytes: bytes::Bytes) -> Payload<S> {
+        let (_, mut pl) = crate::h1::Payload::create(true);
+        pl.unread_data(bytes);
+        self::Payload::from(pl)
+    }
+
+    /// Create Payload from `Vec<u8>` bytes
+    pub fn from_u8_bytes(u8_bytes: Vec<u8>) -> Payload<S> {
+        let (_, mut pl) = crate::h1::Payload::create(true);
+        let bytes = bytes::Bytes::from(u8_bytes);
+        pl.unread_data(bytes);
+        self::Payload::from(pl)
+    }
+
     /// Takes current payload and replaces it with `None` value
     pub fn take(&mut self) -> Payload<S> {
         mem::replace(self, Payload::None)