FreshRSS
/
NetNewsWire
mirror of https://github.com/Ranchero-Software/NetNewsWire.git
1
0
Fork 0
Code Issues Packages Projects Releases Wiki Activity

Change the validation code to always discard any pending requests for validation, and focus on the latest request. This works well for our purposes and avoids us queueing up a validation request and then having it somehow come in later than a more up-to-date request that may pertain to a different window or tab.

This commit is contained in:
Daniel Jalkut 2018-08-19 17:55:46 -04:00
parent 6caf85b598
commit ab810e9f1c
1 changed files with 21 additions and 9 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

22
Safari Extension/SafariExtensionHandler.swift
View File

@ -18,7 +18,7 @@ class SafariExtensionHandler: SFSafariExtensionHandler {
// to verify whether our code is installed.
// I tried to use a NSMapTable from String to the closure directly, but Swift
// complains that the object as to be a class type.
// complains that the object has to be a class type.
typealias ValidationHandler = (Bool, String) -> Void
class ValidationWrapper {
let validationHandler: ValidationHandler
@ -30,6 +30,7 @@ class SafariExtensionHandler: SFSafariExtensionHandler {
// Maps from UUID to a validation wrapper
static var gPingPongMap = Dictionary<String, ValidationWrapper>()
static var validationQueue = DispatchQueue(label: "Toolbar Validation")
// Bottleneck for calling through to a validation handler we have saved, and removing it from the list.
static func callValidationHandler(forHandlerID handlerID: String, withShouldValidate shouldValidate: Bool) {
@ -39,8 +40,6 @@ class SafariExtensionHandler: SFSafariExtensionHandler {
}
}
var validationQueue = DispatchQueue(label: "Toolbar Validation")
override func messageReceived(withName messageName: String, from page: SFSafariPage, userInfo: [String : Any]?) {
if (messageName == "subscribeToFeed") {
if let feedURLString = userInfo?["url"] as? String {
@ -73,12 +72,25 @@ class SafariExtensionHandler: SFSafariExtensionHandler {
let uniqueValidationID = NSUUID().uuidString
SafariExtensionHandler.validationQueue.sync {
// Save it right away to eliminate any doubt of whether the handler gets deallocated while
// we are waiting for a callback from the getActiveTab or getActivatePage methods below.
let validationWrapper = ValidationWrapper(validationHandler: validationHandler)
SafariExtensionHandler.gPingPongMap[uniqueValidationID] = validationWrapper
validationQueue.sync {
// To avoid problems with validation handlers dispatched after we've, for example,
// switched to a new tab, we aggressively clear out the map of any pending validations,
// and focus only on the newest validation request we've been asked for.
for thisValidationID in SafariExtensionHandler.gPingPongMap.keys {
if thisValidationID != uniqueValidationID {
// Default to valid ... we'll know soon enough whether the latest state
// is actually still valid or not...
SafariExtensionHandler.callValidationHandler(forHandlerID: thisValidationID, withShouldValidate: true);
}
}
// See comments above where gPingPongMap is declared. Upon being asked to validate the
// toolbar icon for a specific page, we save the validationHandler and postpone calling
// it until we have either received a response from our installed JavaScript, or until
@ -101,7 +113,7 @@ class SafariExtensionHandler: SFSafariExtensionHandler {
// Capture the uniqueValidationID to ensure it doesn't change out from under us on a future call
activePage.dispatchMessageToScript(withName: "ping", userInfo: ["validationID": uniqueValidationID])
let pongTimeoutInNanoseconds = Int(NSEC_PER_SEC * UInt64(1))
let pongTimeoutInNanoseconds = Int(Double(NSEC_PER_SEC) * 0.5)
let timeoutDeadline = DispatchTime.now() + DispatchTimeInterval.nanoseconds(pongTimeoutInNanoseconds)
DispatchQueue.main.asyncAfter(deadline: timeoutDeadline, execute: { [timedOutValidationID = uniqueValidationID] in
SafariExtensionHandler.callValidationHandler(forHandlerID: timedOutValidationID, withShouldValidate:false)