response header rework (#1869)

actix-http/src/header/into_value.rs

@@ -0,0 +1,131 @@
+use std::convert::TryFrom;
+
+use bytes::Bytes;
+use http::{header::InvalidHeaderValue, Error as HttpError, HeaderValue};
+use mime::Mime;
+
+/// A trait for any object that can be Converted to a `HeaderValue`
+pub trait IntoHeaderValue: Sized {
+    /// The type returned in the event of a conversion error.
+    type Error: Into<HttpError>;
+
+    /// Try to convert value to a HeaderValue.
+    fn try_into_value(self) -> Result<HeaderValue, Self::Error>;
+}
+
+impl IntoHeaderValue for HeaderValue {
+    type Error = InvalidHeaderValue;
+
+    #[inline]
+    fn try_into_value(self) -> Result<HeaderValue, Self::Error> {
+        Ok(self)
+    }
+}
+
+impl IntoHeaderValue for &HeaderValue {
+    type Error = InvalidHeaderValue;
+
+    #[inline]
+    fn try_into_value(self) -> Result<HeaderValue, Self::Error> {
+        Ok(self.clone())
+    }
+}
+
+impl IntoHeaderValue for &str {
+    type Error = InvalidHeaderValue;
+
+    #[inline]
+    fn try_into_value(self) -> Result<HeaderValue, Self::Error> {
+        self.parse()
+    }
+}
+
+impl IntoHeaderValue for &[u8] {
+    type Error = InvalidHeaderValue;
+
+    #[inline]
+    fn try_into_value(self) -> Result<HeaderValue, Self::Error> {
+        HeaderValue::from_bytes(self)
+    }
+}
+
+impl IntoHeaderValue for Bytes {
+    type Error = InvalidHeaderValue;
+
+    #[inline]
+    fn try_into_value(self) -> Result<HeaderValue, Self::Error> {
+        HeaderValue::from_maybe_shared(self)
+    }
+}
+
+impl IntoHeaderValue for Vec<u8> {
+    type Error = InvalidHeaderValue;
+
+    #[inline]
+    fn try_into_value(self) -> Result<HeaderValue, Self::Error> {
+        HeaderValue::try_from(self)
+    }
+}
+
+impl IntoHeaderValue for String {
+    type Error = InvalidHeaderValue;
+
+    #[inline]
+    fn try_into_value(self) -> Result<HeaderValue, Self::Error> {
+        HeaderValue::try_from(self)
+    }
+}
+
+impl IntoHeaderValue for usize {
+    type Error = InvalidHeaderValue;
+
+    #[inline]
+    fn try_into_value(self) -> Result<HeaderValue, Self::Error> {
+        HeaderValue::try_from(self.to_string())
+    }
+}
+
+impl IntoHeaderValue for i64 {
+    type Error = InvalidHeaderValue;
+
+    #[inline]
+    fn try_into_value(self) -> Result<HeaderValue, Self::Error> {
+        HeaderValue::try_from(self.to_string())
+    }
+}
+
+impl IntoHeaderValue for u64 {
+    type Error = InvalidHeaderValue;
+
+    #[inline]
+    fn try_into_value(self) -> Result<HeaderValue, Self::Error> {
+        HeaderValue::try_from(self.to_string())
+    }
+}
+
+impl IntoHeaderValue for i32 {
+    type Error = InvalidHeaderValue;
+
+    #[inline]
+    fn try_into_value(self) -> Result<HeaderValue, Self::Error> {
+        HeaderValue::try_from(self.to_string())
+    }
+}
+
+impl IntoHeaderValue for u32 {
+    type Error = InvalidHeaderValue;
+
+    #[inline]
+    fn try_into_value(self) -> Result<HeaderValue, Self::Error> {
+        HeaderValue::try_from(self.to_string())
+    }
+}
+
+impl IntoHeaderValue for Mime {
+    type Error = InvalidHeaderValue;
+
+    #[inline]
+    fn try_into_value(self) -> Result<HeaderValue, Self::Error> {
+        HeaderValue::try_from(format!("{}", self))
+    }
+}