Performance Timeline API

components/script/dom/performance.rs

@@ -2,22 +2,79 @@
  * License, v. 2.0. If a copy of the MPL was not distributed with this
  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
 
+use dom::bindings::cell::DOMRefCell;
 use dom::bindings::codegen::Bindings::PerformanceBinding;
-use dom::bindings::codegen::Bindings::PerformanceBinding::PerformanceMethods;
+use dom::bindings::codegen::Bindings::PerformanceBinding::{DOMHighResTimeStamp, PerformanceMethods};
+use dom::bindings::codegen::Bindings::PerformanceBinding::PerformanceEntryList as DOMPerformanceEntryList;
 use dom::bindings::js::{JS, Root};
 use dom::bindings::num::Finite;
-use dom::bindings::reflector::{Reflector, reflect_dom_object};
+use dom::bindings::refcounted::Trusted;
+use dom::bindings::reflector::{DomObject, Reflector, reflect_dom_object};
+use dom::bindings::str::DOMString;
+use dom::performanceentry::PerformanceEntry;
+use dom::performanceobserver::PerformanceObserver as DOMPerformanceObserver;
 use dom::performancetiming::PerformanceTiming;
 use dom::window::Window;
 use dom_struct::dom_struct;
+use script_thread::{Runnable, ScriptThread};
+use std::cell::Cell;
 use time;
 
-pub type DOMHighResTimeStamp = Finite<f64>;
+/// Implementation of a list of PerformanceEntry items shared by the
+/// Performance and PerformanceObserverEntryList interfaces implementations.
+#[derive(HeapSizeOf, JSTraceable)]
+pub struct PerformanceEntryList {
+    entries: DOMPerformanceEntryList,
+}
+
+impl PerformanceEntryList {
+    pub fn new(entries: DOMPerformanceEntryList) -> Self {
+        PerformanceEntryList {
+            entries,
+        }
+    }
+
+    pub fn get_entries(&self) -> Vec<Root<PerformanceEntry>> {
+        self.entries.clone()
+    }
+
+    pub fn get_entries_by_type(&self, entry_type: DOMString) -> Vec<Root<PerformanceEntry>> {
+        self.entries.iter().filter(|e| *e.entry_type() == entry_type)
+                           .map(|e| e.clone())
+                           .collect()
+    }
+
+    pub fn get_entries_by_name(&self, name: DOMString, entry_type: Option<DOMString>)
+        -> Vec<Root<PerformanceEntry>> {
+        self.entries.iter().filter(|e|
+            *e.name() == name &&
+            entry_type.as_ref().map_or(true, |type_| *e.entry_type() == *type_)
+        ).map(|e| e.clone()).collect()
+    }
+}
+
+impl IntoIterator for PerformanceEntryList {
+    type Item = Root<PerformanceEntry>;
+    type IntoIter = ::std::vec::IntoIter<Root<PerformanceEntry>>;
+
+    fn into_iter(self) -> Self::IntoIter {
+        self.entries.into_iter()
+    }
+}
+
+#[derive(HeapSizeOf, JSTraceable)]
+struct PerformanceObserver {
+    observer: Root<DOMPerformanceObserver>,
+    entry_types: Vec<DOMString>,
+}
 
 #[dom_struct]
 pub struct Performance {
     reflector_: Reflector,
     timing: JS<PerformanceTiming>,
+    entries: DOMRefCell<PerformanceEntryList>,
+    observers: DOMRefCell<Vec<PerformanceObserver>>,
+    pending_notification_observers_task: Cell<bool>,
 }
 
 impl Performance {
@@ -29,6 +86,9 @@ impl Performance {
             timing: JS::from_ref(&*PerformanceTiming::new(window,
                                                             navigation_start,
                                                             navigation_start_precise)),
+            entries: DOMRefCell::new(PerformanceEntryList::new(Vec::new())),
+            observers: DOMRefCell::new(Vec::new()),
+            pending_notification_observers_task: Cell::new(false),
         }
     }
 
@@ -41,6 +101,121 @@ impl Performance {
                            window,
                            PerformanceBinding::Wrap)
     }
+
+    /// Add a PerformanceObserver to the list of observers with a set of
+    /// observed entry types.
+    pub fn add_observer(&self,
+                        observer: &DOMPerformanceObserver,
+                        entry_types: Vec<DOMString>) {
+        let mut observers = self.observers.borrow_mut();
+        match observers.iter().position(|o| &(*o.observer) == observer) {
+            // If the observer is already in the list, we only update the observed
+            // entry types.
+            Some(p) => observers[p].entry_types = entry_types,
+            // Otherwise, we create and insert the new PerformanceObserver.
+            None => observers.push(PerformanceObserver {
+                observer: Root::from_ref(observer),
+                entry_types
+            })
+        };
+    }
+
+    /// Remove a PerformanceObserver from the list of observers.
+    pub fn remove_observer(&self, observer: &DOMPerformanceObserver) {
+        let mut observers = self.observers.borrow_mut();
+        let index = match observers.iter().position(|o| &(*o.observer) == observer) {
+            Some(p) => p,
+            None => return,
+        };
+        observers.remove(index);
+    }
+
+    /// Queue a notification for each performance observer interested in
+    /// this type of performance entry and queue a low priority task to
+    /// notify the observers if no other notification task is already queued.
+    ///
+    /// Algorithm spec:
+    /// https://w3c.github.io/performance-timeline/#queue-a-performanceentry
+    ///
+    /// XXX This should be called at some point by the User Timing, Resource
+    ///     Timing, Server Timing and Paint Timing APIs.
+    pub fn queue_entry(&self, entry: &PerformanceEntry,
+                       add_to_performance_entries_buffer: bool) {
+        // Steps 1-3.
+        // Add the performance entry to the list of performance entries that have not
+        // been notified to each performance observer owner, filtering the ones it's
+        // interested in.
+        for o in self.observers.borrow().iter().filter(|o| o.entry_types.contains(entry.entry_type())) {
+            o.observer.queue_entry(entry);
+        }
+
+        // Step 4.
+        // If the "add to performance entry buffer flag" is set, add the
+        // new entry to the buffer.
+        if add_to_performance_entries_buffer {
+            self.entries.borrow_mut().entries.push(Root::from_ref(entry));
+        }
+
+        // Step 5.
+        // If there is already a queued notification task, we just bail out.
+        if self.pending_notification_observers_task.get() {
+            return;
+        }
+
+        // Step 6.
+        // Queue a new notification task.
+        self.pending_notification_observers_task.set(true);
+        let global = self.global();
+        let window = global.as_window();
+        let task_source = window.performance_timeline_task_source();
+        task_source.queue_notification(self, window);
+    }
+
+    /// Observers notifications task.
+    ///
+    /// Algorithm spec (step 7):
+    /// https://w3c.github.io/performance-timeline/#queue-a-performanceentry
+    fn notify_observers(&self) {
+        // Step 7.1.
+        self.pending_notification_observers_task.set(false);
+
+        // Step 7.2.
+        // We have to operate over a copy of the performance observers to avoid
+        // the risk of an observer's callback modifying the list of registered
+        // observers.
+        let observers: Vec<Root<DOMPerformanceObserver>> =
+            self.observers.borrow().iter()
+                                   .map(|o| DOMPerformanceObserver::new(&self.global(),
+                                                                        o.observer.callback(),
+                                                                        o.observer.entries()))
+                                   .collect();
+
+        // Step 7.3.
+        for o in observers.iter() {
+            o.notify();
+        }
+    }
+}
+
+pub struct NotifyPerformanceObserverRunnable {
+    owner: Trusted<Performance>,
+}
+
+impl NotifyPerformanceObserverRunnable {
+    pub fn new(owner: Trusted<Performance>) -> Self {
+        NotifyPerformanceObserverRunnable {
+            owner,
+        }
+    }
+}
+
+impl Runnable for NotifyPerformanceObserverRunnable {
+    fn name(&self) -> &'static str { "NotifyPerformanceObserverRunnable" }
+
+    fn main_thread_handler(self: Box<NotifyPerformanceObserverRunnable>,
+                           _: &ScriptThread) {
+        self.owner.root().notify_observers();
+    }
 }
 
 impl PerformanceMethods for Performance {
@@ -55,4 +230,20 @@ impl PerformanceMethods for Performance {
         let now = (time::precise_time_ns() as f64 - nav_start) / 1000000 as f64;
         Finite::wrap(now)
     }
+
+    // https://www.w3.org/TR/performance-timeline-2/#dom-performance-getentries
+    fn GetEntries(&self) -> Vec<Root<PerformanceEntry>> {
+        self.entries.borrow().get_entries()
+    }
+
+    // https://www.w3.org/TR/performance-timeline-2/#dom-performance-getentriesbytype
+    fn GetEntriesByType(&self, entry_type: DOMString) -> Vec<Root<PerformanceEntry>> {
+        self.entries.borrow().get_entries_by_type(entry_type)
+    }
+
+    // https://www.w3.org/TR/performance-timeline-2/#dom-performance-getentriesbyname
+    fn GetEntriesByName(&self, name: DOMString, entry_type: Option<DOMString>)
+        -> Vec<Root<PerformanceEntry>> {
+        self.entries.borrow().get_entries_by_name(name, entry_type)
+    }
 }