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mirror of https://github.com/fafhrd91/actix-web synced 2025-03-28 17:48:39 +01:00
actix-web/actix-http/src/extensions.rs
2021-12-05 04:57:17 +00:00

425 lines
12 KiB
Rust

use std::{
any::{Any, TypeId},
fmt,
};
use ahash::AHashMap;
/// A type map for request extensions.
///
/// All entries into this map must be owned types (or static references).
#[derive(Default)]
pub struct Extensions {
/// Use AHasher with a std HashMap with for faster lookups on the small `TypeId` keys.
map: AHashMap<TypeId, Box<dyn Any>>,
}
impl Extensions {
/// Creates an empty `Extensions`.
#[inline]
pub fn new() -> Extensions {
Extensions {
map: AHashMap::default(),
}
}
/// Insert an item into the map.
///
/// If an item of this type was already stored, it will be replaced and returned.
///
/// ```
/// # use actix_http::Extensions;
/// let mut map = Extensions::new();
/// assert_eq!(map.insert(""), None);
/// assert_eq!(map.insert(1u32), None);
/// assert_eq!(map.insert(2u32), Some(1u32));
/// assert_eq!(*map.get::<u32>().unwrap(), 2u32);
/// ```
pub fn insert<T: 'static>(&mut self, val: T) -> Option<T> {
self.map
.insert(TypeId::of::<T>(), Box::new(val))
.and_then(downcast_owned)
}
/// Check if map contains an item of a given type.
///
/// ```
/// # use actix_http::Extensions;
/// let mut map = Extensions::new();
/// assert!(!map.contains::<u32>());
///
/// assert_eq!(map.insert(1u32), None);
/// assert!(map.contains::<u32>());
/// ```
pub fn contains<T: 'static>(&self) -> bool {
self.map.contains_key(&TypeId::of::<T>())
}
/// Get a reference to an item of a given type.
///
/// ```
/// # use actix_http::Extensions;
/// let mut map = Extensions::new();
/// map.insert(1u32);
/// assert_eq!(map.get::<u32>(), Some(&1u32));
/// ```
pub fn get<T: 'static>(&self) -> Option<&T> {
self.map
.get(&TypeId::of::<T>())
.and_then(|boxed| boxed.downcast_ref())
}
/// Get a mutable reference to an item of a given type.
///
/// ```
/// # use actix_http::Extensions;
/// let mut map = Extensions::new();
/// map.insert(1u32);
/// assert_eq!(map.get_mut::<u32>(), Some(&mut 1u32));
/// ```
pub fn get_mut<T: 'static>(&mut self) -> Option<&mut T> {
self.map
.get_mut(&TypeId::of::<T>())
.and_then(|boxed| boxed.downcast_mut())
}
/// Remove an item from the map of a given type.
///
/// If an item of this type was already stored, it will be returned.
///
/// ```
/// # use actix_http::Extensions;
/// let mut map = Extensions::new();
///
/// map.insert(1u32);
/// assert_eq!(map.get::<u32>(), Some(&1u32));
///
/// assert_eq!(map.remove::<u32>(), Some(1u32));
/// assert!(!map.contains::<u32>());
/// ```
pub fn remove<T: 'static>(&mut self) -> Option<T> {
self.map.remove(&TypeId::of::<T>()).and_then(downcast_owned)
}
/// Clear the `Extensions` of all inserted extensions.
///
/// ```
/// # use actix_http::Extensions;
/// let mut map = Extensions::new();
///
/// map.insert(1u32);
/// assert!(map.contains::<u32>());
///
/// map.clear();
/// assert!(!map.contains::<u32>());
/// ```
#[inline]
pub fn clear(&mut self) {
self.map.clear();
}
/// Extends self with the items from another `Extensions`.
pub fn extend(&mut self, other: Extensions) {
self.map.extend(other.map);
}
/// Sets (or overrides) items from cloneable extensions map into this map.
pub(crate) fn clone_from(&mut self, other: &CloneableExtensions) {
for (k, val) in &other.map {
self.map.insert(*k, (**val).clone_to_any());
}
}
}
impl fmt::Debug for Extensions {
fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
f.debug_struct("Extensions").finish()
}
}
fn downcast_owned<T: 'static>(boxed: Box<dyn Any>) -> Option<T> {
boxed.downcast().ok().map(|boxed| *boxed)
}
#[doc(hidden)]
pub trait CloneToAny {
/// Cast `self` into an `Any` reference.
#[cfg(test)]
fn any_ref(&self) -> &dyn Any;
/// Clone `self` to a new `Box<Any>` object.
fn clone_to_any(&self) -> Box<dyn Any>;
/// Clone `self` to a new `Box<CloneAny>` object.
fn clone_to_clone_any(&self) -> Box<dyn CloneAny>;
}
impl<T: Clone + Any> CloneToAny for T {
#[cfg(test)]
fn any_ref(&self) -> &dyn Any {
&*self
}
#[inline]
fn clone_to_any(&self) -> Box<dyn Any> {
Box::new(self.clone())
}
#[inline]
fn clone_to_clone_any(&self) -> Box<dyn CloneAny> {
Box::new(self.clone())
}
}
/// An [`Any`] trait with an additional [`Clone`] requirement.
pub trait CloneAny: CloneToAny + Any {}
impl<T: Any + Clone> CloneAny for T {}
impl Clone for Box<dyn CloneAny> {
#[inline]
fn clone(&self) -> Self {
(**self).clone_to_clone_any()
}
}
trait UncheckedAnyExt {
/// # Safety
/// Caller must ensure type `T` is true type.
#[inline]
unsafe fn downcast_unchecked<T: 'static>(self: Box<Self>) -> Box<T> {
Box::from_raw(Box::into_raw(self) as *mut T)
}
}
impl UncheckedAnyExt for dyn CloneAny {}
/// A type map for `on_connect` extensions.
///
/// All entries into this map must be owned types and implement `Clone` trait.
///
/// Many requests can be processed for each connection but the `on_connect` will only be run once
/// when the connection is opened. Therefore, items added to this special map type need to be cloned
/// into the regular extensions map for each request. Most useful connection information types are
/// cloneable already but you can use reference counted wrappers if not.
#[derive(Default)]
pub struct CloneableExtensions {
/// Use AHasher with a std HashMap with for faster lookups on the small `TypeId` keys.
map: AHashMap<TypeId, Box<dyn CloneAny>>,
}
impl CloneableExtensions {
/// Insert an item into the map.
///
/// If an item of this type was already stored, it will be replaced and returned.
///
/// # Examples
/// ```
/// # use actix_http::Extensions;
/// let mut map = Extensions::new();
/// assert_eq!(map.insert(""), None);
/// assert_eq!(map.insert(1u32), None);
/// assert_eq!(map.insert(2u32), Some(1u32));
/// assert_eq!(*map.get::<u32>().unwrap(), 2u32);
/// ```
pub fn insert<T: CloneAny>(&mut self, val: T) -> Option<T> {
self.map
.insert(TypeId::of::<T>(), Box::new(val))
.map(|boxed| {
// Safety:
// Box is owned and `T` is known to be true type from map.
*unsafe { UncheckedAnyExt::downcast_unchecked::<T>(boxed) }
})
}
#[cfg(test)]
fn get<T: CloneAny>(&self) -> Option<&T> {
self.map
.get(&TypeId::of::<T>())
.and_then(|boxed| boxed.as_ref().any_ref().downcast_ref())
}
}
#[cfg(test)]
mod tests {
use super::*;
#[test]
fn test_remove() {
let mut map = Extensions::new();
map.insert::<i8>(123);
assert!(map.get::<i8>().is_some());
map.remove::<i8>();
assert!(map.get::<i8>().is_none());
}
#[test]
fn test_clear() {
let mut map = Extensions::new();
map.insert::<i8>(8);
map.insert::<i16>(16);
map.insert::<i32>(32);
assert!(map.contains::<i8>());
assert!(map.contains::<i16>());
assert!(map.contains::<i32>());
map.clear();
assert!(!map.contains::<i8>());
assert!(!map.contains::<i16>());
assert!(!map.contains::<i32>());
map.insert::<i8>(10);
assert_eq!(*map.get::<i8>().unwrap(), 10);
}
#[test]
fn test_integers() {
static A: u32 = 8;
let mut map = Extensions::new();
map.insert::<i8>(8);
map.insert::<i16>(16);
map.insert::<i32>(32);
map.insert::<i64>(64);
map.insert::<i128>(128);
map.insert::<u8>(8);
map.insert::<u16>(16);
map.insert::<u32>(32);
map.insert::<u64>(64);
map.insert::<u128>(128);
map.insert::<&'static u32>(&A);
assert!(map.get::<i8>().is_some());
assert!(map.get::<i16>().is_some());
assert!(map.get::<i32>().is_some());
assert!(map.get::<i64>().is_some());
assert!(map.get::<i128>().is_some());
assert!(map.get::<u8>().is_some());
assert!(map.get::<u16>().is_some());
assert!(map.get::<u32>().is_some());
assert!(map.get::<u64>().is_some());
assert!(map.get::<u128>().is_some());
assert!(map.get::<&'static u32>().is_some());
}
#[test]
fn test_composition() {
struct Magi<T>(pub T);
struct Madoka {
pub god: bool,
}
struct Homura {
pub attempts: usize,
}
struct Mami {
pub guns: usize,
}
let mut map = Extensions::new();
map.insert(Magi(Madoka { god: false }));
map.insert(Magi(Homura { attempts: 0 }));
map.insert(Magi(Mami { guns: 999 }));
assert!(!map.get::<Magi<Madoka>>().unwrap().0.god);
assert_eq!(0, map.get::<Magi<Homura>>().unwrap().0.attempts);
assert_eq!(999, map.get::<Magi<Mami>>().unwrap().0.guns);
}
#[test]
fn test_extensions() {
#[derive(Debug, PartialEq)]
struct MyType(i32);
let mut extensions = Extensions::new();
extensions.insert(5i32);
extensions.insert(MyType(10));
assert_eq!(extensions.get(), Some(&5i32));
assert_eq!(extensions.get_mut(), Some(&mut 5i32));
assert_eq!(extensions.remove::<i32>(), Some(5i32));
assert!(extensions.get::<i32>().is_none());
assert_eq!(extensions.get::<bool>(), None);
assert_eq!(extensions.get(), Some(&MyType(10)));
}
#[test]
fn test_extend() {
#[derive(Debug, PartialEq)]
struct MyType(i32);
let mut extensions = Extensions::new();
extensions.insert(5i32);
extensions.insert(MyType(10));
let mut other = Extensions::new();
other.insert(15i32);
other.insert(20u8);
extensions.extend(other);
assert_eq!(extensions.get(), Some(&15i32));
assert_eq!(extensions.get_mut(), Some(&mut 15i32));
assert_eq!(extensions.remove::<i32>(), Some(15i32));
assert!(extensions.get::<i32>().is_none());
assert_eq!(extensions.get::<bool>(), None);
assert_eq!(extensions.get(), Some(&MyType(10)));
assert_eq!(extensions.get(), Some(&20u8));
assert_eq!(extensions.get_mut(), Some(&mut 20u8));
}
#[test]
fn test_clone_from() {
#[derive(Clone)]
struct NonCopy {
num: u8,
}
let mut ext = Extensions::new();
ext.insert(2isize);
assert_eq!(ext.get::<isize>(), Some(&2isize));
let mut more_ext = CloneableExtensions::default();
more_ext.insert(3isize);
more_ext.insert(3usize);
more_ext.insert(NonCopy { num: 8 });
ext.clone_from(&more_ext);
assert_eq!(ext.get::<isize>(), Some(&3isize));
assert_eq!(ext.get::<usize>(), Some(&3usize));
assert_eq!(more_ext.get::<isize>(), Some(&3isize));
assert_eq!(more_ext.get::<usize>(), Some(&3usize));
assert!(ext.get::<NonCopy>().is_some());
assert!(more_ext.get::<NonCopy>().is_some());
}
#[test]
fn boxes_not_aliased() {
let a: Box<dyn CloneAny> = Box::new(42);
let b = a.clone_to_clone_any();
assert_ne!(Box::into_raw(a) as *const (), Box::into_raw(b) as *const ());
let a: Box<dyn CloneAny> = Box::new(42);
let b = a.clone_to_any();
assert_ne!(Box::into_raw(a) as *const (), Box::into_raw(b) as *const ());
}
}