Create HttpStatus to safely deal with HTTP responses status. (#33581)

Signed-off-by: webbeef <me@webbeef.org>

components/shared/net/http_status.rs

@@ -0,0 +1,117 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at https://mozilla.org/MPL/2.0/. */
+
+#![deny(unsafe_code)]
+
+use std::ops::RangeBounds;
+
+use serde::{Deserialize, Serialize};
+
+use crate::{MallocSizeOf, StatusCode};
+
+/// A representation of a HTTP Status Code and Message that can be used for
+/// DOM Response objects and other cases.
+/// These objects are immutable once created.
+#[derive(Clone, Debug, Deserialize, MallocSizeOf, PartialEq, Serialize)]
+pub struct HttpStatus {
+    code: u16,
+    message: Vec<u8>,
+}
+
+impl HttpStatus {
+    /// Creates a new HttpStatus for a valid status code.
+    pub fn new(code: StatusCode, message: Vec<u8>) -> Self {
+        Self {
+            code: code.as_u16(),
+            message,
+        }
+    }
+
+    /// Creates a new HttpStatus from a raw status code, but will panic
+    /// if the code is not in the 100 to 599 valid range.
+    pub fn new_raw(code: u16, message: Vec<u8>) -> Self {
+        if !(100..=599).contains(&code) {
+            panic!(
+                "HttpStatus code must be in the range 100 to 599, inclusive, but is {}",
+                code
+            );
+        }
+
+        Self { code, message }
+    }
+
+    /// Creates an instance that represents a Response.error() instance.
+    pub fn new_error() -> Self {
+        Self {
+            code: 0,
+            message: vec![],
+        }
+    }
+
+    /// Returns the StatusCode for non-error cases, panics otherwise.
+    pub fn code(&self) -> StatusCode {
+        StatusCode::from_u16(self.code).expect("HttpStatus code is 0, can't return a StatusCode")
+    }
+
+    /// Returns the StatusCode if not an error instance, or None otherwise.
+    pub fn try_code(&self) -> Option<StatusCode> {
+        StatusCode::from_u16(self.code).ok()
+    }
+
+    /// Returns the u16 representation of the access code. This is usable both for
+    /// valid HTTP status codes and in the error case.
+    pub fn raw_code(&self) -> u16 {
+        self.code
+    }
+
+    /// Get access to a reference of the message part.
+    pub fn message(&self) -> &[u8] {
+        &self.message
+    }
+
+    /// Helper that relays is_success() from the underlying code.
+    pub fn is_success(&self) -> bool {
+        StatusCode::from_u16(self.code).map_or(false, |s| s.is_success())
+    }
+
+    /// True when the object was created with `new_error`.
+    pub fn is_error(&self) -> bool {
+        self.code == 0
+    }
+
+    /// Returns true if this status is in the given range.
+    /// Always return false for error statuses.
+    pub fn in_range<T: RangeBounds<u16>>(&self, range: T) -> bool {
+        self.code != 0 && range.contains(&self.code)
+    }
+}
+
+impl Default for HttpStatus {
+    /// The default implementation creates a "200 OK" response.
+    fn default() -> Self {
+        Self {
+            code: 200,
+            message: b"OK".to_vec(),
+        }
+    }
+}
+
+impl PartialEq<StatusCode> for HttpStatus {
+    fn eq(&self, other: &StatusCode) -> bool {
+        self.code == other.as_u16()
+    }
+}
+
+impl From<StatusCode> for HttpStatus {
+    fn from(code: StatusCode) -> Self {
+        Self {
+            code: code.as_u16(),
+            message: code
+                .canonical_reason()
+                .unwrap_or_default()
+                .as_bytes()
+                .to_vec(),
+        }
+    }
+}