Files
ReadViewSDK/Sources/RDEpubReaderView/EPUBCore/RDEPUBResourceURLSchemeHandler.swift
T
shenlei 3e60bf1869 修复阅读器资源、朗读与持久化稳定性
阅读器在多会话朗读、加密 EPUB 资源、并发打开同一本书和多 UserDefaults 容器等场景下,存在旧异步结果覆盖新状态、锁屏控制串会话、大型明文资源被误拒绝、解压半成品被复用及标注跨容器混用的风险;同时高亮、书签、搜索和设置面板的空状态与自动化可访问性入口不完整。\n\n本次为朗读会话引入代次和当前 utterance 校验,远程控制改为仅响应当前会话并按自身 token 清理;加密资源 provider 先判定是否实际返回解密数据,明文大资源继续流式读取;解压缓存串行化以避免并发复用未完成目录。书签与高亮迁移至受保护文件,按 UserDefaults 容器隔离命名空间,保留标准容器旧文件兼容并确保新副本成功落盘后才删除历史数据。\n\n同步调整缓存淘汰、FoundationModels 弱链接、搜索/标注/设置面板交互与 UI 测试,并更新 Pod 生成配置及 API、风险文档。已执行 git diff --check 和 ReadViewDemo Debug Simulator 构建,结果为 BUILD SUCCEEDED。
2026-07-30 20:52:21 +09:00

437 lines
16 KiB
Swift

import Foundation
import WebKit
public final class RDEPUBResourceURLSchemeHandler: NSObject, WKURLSchemeHandler {
struct DebugMetrics {
let streamedResponses: Int
let inMemoryResponses: Int
let failures: Int
}
public static let scheme = "ss-reader"
public static let host = "book"
/// 单个资源走「整体读入内存」分支时的上限。超过则优雅失败而不是冒着
/// 内存峰值被系统终止的风险。只影响无法流式的分支(配置了加密资源
/// provider 时密文必须整体解密),流式分支不受此限制。
public static var maximumInMemoryResourceBytes: UInt64 = 64 * 1024 * 1024
private weak var parser: RDEPUBParser?
private let fileManager = FileManager.default
private let syncQueue = DispatchQueue(label: "com.ssreaderview.epub.scheme-handler")
private let ioQueue = DispatchQueue(label: "com.ssreaderview.epub.scheme-handler.io", qos: .utility)
private var activeTasks: [ObjectIdentifier: Bool] = [:]
private static let debugMetricsQueue = DispatchQueue(label: "com.ssreaderview.epub.scheme-handler.metrics")
private static var streamedResponseCount = 0
private static var inMemoryResponseCount = 0
private static var failureCount = 0
public init(parser: RDEPUBParser) {
self.parser = parser
super.init()
}
static func resetDebugMetrics() {
debugMetricsQueue.sync {
streamedResponseCount = 0
inMemoryResponseCount = 0
failureCount = 0
}
}
static func debugMetricsSnapshot() -> DebugMetrics {
debugMetricsQueue.sync {
DebugMetrics(
streamedResponses: streamedResponseCount,
inMemoryResponses: inMemoryResponseCount,
failures: failureCount
)
}
}
public func webView(_ webView: WKWebView, start urlSchemeTask: any WKURLSchemeTask) {
let taskID = ObjectIdentifier(urlSchemeTask as AnyObject)
syncQueue.sync {
activeTasks[taskID] = true
}
let requestURL = urlSchemeTask.request.url
RDEPUBWebViewDebug.logSchemeTask("ResourceScheme", requestURL: requestURL, event: "start")
guard let parser,
let requestURL,
let fileURL = parser.fileURL(forResourceURL: requestURL),
fileManager.fileExists(atPath: fileURL.path) else {
if let requestURL, Self.isOptionalResource(requestURL) {
RDEPUBWebViewDebug.logSchemeTask("ResourceScheme", requestURL: requestURL, event: "missing-optional-resource")
let response = URLResponse(
url: requestURL,
mimeType: Self.mimeType(for: requestURL.pathExtension),
expectedContentLength: 0,
textEncodingName: Self.textEncodingName(for: requestURL.pathExtension)
)
// H-08 fix: These calls happen synchronously in webView(_:start:) which
// runs on the same queue WebKit calls start on, so no thread violation here.
urlSchemeTask.didReceive(response)
urlSchemeTask.didReceive(Data())
urlSchemeTask.didFinish()
} else {
RDEPUBWebViewDebug.logSchemeTask("ResourceScheme", requestURL: requestURL, event: "missing-file")
Self.recordFailure()
urlSchemeTask.didFailWithError(NSError(domain: NSURLErrorDomain, code: NSURLErrorFileDoesNotExist))
}
clearTask(taskID)
return
}
RDEPUBWebViewDebug.logSchemeTask("ResourceScheme", requestURL: requestURL, fileURL: fileURL, event: "resolved")
let fileSize = resourceSize(for: fileURL)
// Provider 可以只解密部分资源并对明文资源返回 nil。先在 IO 队列确认是否
// 真的拿到解密数据,再决定是否需要受内存上限约束,不能只因 provider 存在
// 就拒绝大型明文音视频或图片。
if parser.resourceDataProvider != nil {
respondWithProvidedDataOrFile(
fileURL: fileURL,
requestURL: requestURL,
taskID: taskID,
urlSchemeTask: urlSchemeTask,
fileSize: fileSize
)
} else if let fileSize, fileSize > 524_288 {
respondWithStreaming(fileURL: fileURL, requestURL: requestURL, taskID: taskID, urlSchemeTask: urlSchemeTask, fileSize: fileSize)
} else {
respondWithInMemoryData(fileURL: fileURL, requestURL: requestURL, taskID: taskID, urlSchemeTask: urlSchemeTask)
}
}
public func webView(_ webView: WKWebView, stop urlSchemeTask: any WKURLSchemeTask) {
RDEPUBWebViewDebug.logSchemeTask("ResourceScheme", requestURL: urlSchemeTask.request.url, event: "stop")
clearTask(ObjectIdentifier(urlSchemeTask as AnyObject))
}
private func clearTask(_ id: ObjectIdentifier) {
syncQueue.sync {
activeTasks[id] = nil
}
}
private func isTaskActive(_ id: ObjectIdentifier) -> Bool {
syncQueue.sync {
activeTasks[id] == true
}
}
private func resourceSize(for url: URL) -> UInt64? {
guard let attrs = try? fileManager.attributesOfItem(atPath: url.path),
let size = attrs[.size] as? UInt64 else {
return nil
}
return size
}
private func respondWithProvidedDataOrFile(
fileURL: URL,
requestURL: URL,
taskID: ObjectIdentifier,
urlSchemeTask: any WKURLSchemeTask,
fileSize: UInt64?
) {
ioQueue.async { [weak self] in
guard let self else { return }
guard self.isTaskActive(taskID) else { return }
if let provided = self.parser?.providedResourceData(at: fileURL) {
guard UInt64(provided.count) <= Self.maximumInMemoryResourceBytes else {
self.respondWithOversizeFailure(
fileURL: fileURL,
requestURL: requestURL,
taskID: taskID,
urlSchemeTask: urlSchemeTask,
byteCount: UInt64(provided.count)
)
return
}
self.respondWithData(provided, fileURL: fileURL, requestURL: requestURL, taskID: taskID, urlSchemeTask: urlSchemeTask)
} else if let fileSize, fileSize > 524_288 {
self.respondWithStreaming(fileURL: fileURL, requestURL: requestURL, taskID: taskID, urlSchemeTask: urlSchemeTask, fileSize: fileSize)
} else {
self.respondWithInMemoryData(fileURL: fileURL, requestURL: requestURL, taskID: taskID, urlSchemeTask: urlSchemeTask, skipsProvider: true)
}
}
}
private func respondWithOversizeFailure(
fileURL: URL,
requestURL: URL,
taskID: ObjectIdentifier,
urlSchemeTask: any WKURLSchemeTask,
byteCount: UInt64
) {
RDEPUBWebViewDebug.logSchemeTask(
"ResourceScheme",
requestURL: requestURL,
fileURL: fileURL,
event: "rejected-oversize-\(byteCount)"
)
Self.recordFailure()
DispatchQueue.main.async { [weak self] in
guard let self, self.isTaskActive(taskID) else { return }
urlSchemeTask.didFailWithError(
NSError(
domain: NSURLErrorDomain,
code: NSURLErrorDataLengthExceedsMaximum,
userInfo: [NSLocalizedDescriptionKey: "资源超过单资源内存上限(\(byteCount) 字节)"]
)
)
self.clearTask(taskID)
}
}
/// H-08 fix: Dispatch all WKURLSchemeTask completion callbacks to the main queue,
/// ensuring they run on the same serial queue that WebKit calls start() on.
/// Also: cancelled tasks now call didFailWithError(NSURLErrorCancelled) instead
/// of silently returning, satisfying the protocol requirement that every started
/// task must receive a completion callback.
private func respondWithInMemoryData(
fileURL: URL,
requestURL: URL,
taskID: ObjectIdentifier,
urlSchemeTask: any WKURLSchemeTask,
skipsProvider: Bool = false
) {
ioQueue.async { [weak self] in
guard let self else {
DispatchQueue.main.async {
urlSchemeTask.didFailWithError(NSError(domain: NSURLErrorDomain, code: NSURLErrorCancelled))
}
return
}
do {
// 优先向加密资源 provider 索取解密数据,provider 放行的明文文件仍直读磁盘
let data: Data
if !skipsProvider, let provided = self.parser?.providedResourceData(at: fileURL) {
data = provided
} else {
data = try Data(contentsOf: fileURL)
}
guard self.isTaskActive(taskID) else {
DispatchQueue.main.async {
urlSchemeTask.didFailWithError(NSError(domain: NSURLErrorDomain, code: NSURLErrorCancelled))
}
return
}
self.respondWithData(data, fileURL: fileURL, requestURL: requestURL, taskID: taskID, urlSchemeTask: urlSchemeTask)
return
} catch {
guard self.isTaskActive(taskID) else {
DispatchQueue.main.async {
urlSchemeTask.didFailWithError(NSError(domain: NSURLErrorDomain, code: NSURLErrorCancelled))
}
return
}
Self.recordFailure()
RDEPUBWebViewDebug.logSchemeTask("ResourceScheme", requestURL: requestURL, fileURL: fileURL, event: "failed", error: error)
DispatchQueue.main.async {
urlSchemeTask.didFailWithError(error)
}
}
self.clearTask(taskID)
}
}
private func respondWithData(
_ data: Data,
fileURL: URL,
requestURL: URL,
taskID: ObjectIdentifier,
urlSchemeTask: any WKURLSchemeTask
) {
let response = URLResponse(
url: requestURL,
mimeType: Self.mimeType(for: fileURL.pathExtension),
expectedContentLength: data.count,
textEncodingName: Self.textEncodingName(for: fileURL.pathExtension)
)
dispatchTaskSuccessCallback(
taskID: taskID,
urlSchemeTask: urlSchemeTask
) {
urlSchemeTask.didReceive(response)
urlSchemeTask.didReceive(data)
urlSchemeTask.didFinish()
}
Self.recordInMemoryResponse()
RDEPUBWebViewDebug.logSchemeTask("ResourceScheme", requestURL: requestURL, fileURL: fileURL, event: "finished")
}
private func respondWithStreaming(fileURL: URL, requestURL: URL, taskID: ObjectIdentifier, urlSchemeTask: any WKURLSchemeTask, fileSize: UInt64) {
ioQueue.async { [weak self] in
guard let self else {
DispatchQueue.main.async {
urlSchemeTask.didFailWithError(NSError(domain: NSURLErrorDomain, code: NSURLErrorCancelled))
}
return
}
let response = URLResponse(
url: requestURL,
mimeType: Self.mimeType(for: fileURL.pathExtension),
expectedContentLength: Int(fileSize),
textEncodingName: Self.textEncodingName(for: fileURL.pathExtension)
)
self.dispatchTaskCallbackIfActive(taskID: taskID) {
urlSchemeTask.didReceive(response)
}
guard let fileHandle = try? FileHandle(forReadingFrom: fileURL) else {
guard self.isTaskActive(taskID) else {
DispatchQueue.main.async {
urlSchemeTask.didFailWithError(NSError(domain: NSURLErrorDomain, code: NSURLErrorCancelled))
}
return
}
Self.recordFailure()
DispatchQueue.main.async {
urlSchemeTask.didFailWithError(NSError(domain: NSURLErrorDomain, code: NSURLErrorFileDoesNotExist))
}
self.clearTask(taskID)
return
}
let chunkSize = 65_536
defer {
fileHandle.closeFile()
}
while true {
guard self.isTaskActive(taskID) else {
// H-08 fix: Task was cancelled. Send didFailWithError on main queue.
DispatchQueue.main.async {
urlSchemeTask.didFailWithError(NSError(domain: NSURLErrorDomain, code: NSURLErrorCancelled))
}
self.clearTask(taskID)
return
}
let data = fileHandle.readData(ofLength: chunkSize)
if data.isEmpty { break }
self.dispatchTaskCallbackIfActive(taskID: taskID) {
urlSchemeTask.didReceive(data)
}
}
self.dispatchTaskSuccessCallback(
taskID: taskID,
urlSchemeTask: urlSchemeTask
) {
urlSchemeTask.didFinish()
}
Self.recordStreamedResponse()
RDEPUBWebViewDebug.logSchemeTask("ResourceScheme", requestURL: requestURL, fileURL: fileURL, event: "finished-streaming")
}
}
private func dispatchTaskCallbackIfActive(taskID: ObjectIdentifier, _ callback: @escaping () -> Void) {
DispatchQueue.main.async { [weak self] in
guard let self, self.isTaskActive(taskID) else { return }
callback()
}
}
private func dispatchTaskSuccessCallback(
taskID: ObjectIdentifier,
urlSchemeTask: any WKURLSchemeTask,
_ callback: @escaping () -> Void
) {
DispatchQueue.main.async { [weak self] in
guard let self else {
urlSchemeTask.didFailWithError(NSError(domain: NSURLErrorDomain, code: NSURLErrorCancelled))
return
}
guard self.isTaskActive(taskID) else {
urlSchemeTask.didFailWithError(NSError(domain: NSURLErrorDomain, code: NSURLErrorCancelled))
self.clearTask(taskID)
return
}
callback()
self.clearTask(taskID)
}
}
private static func recordStreamedResponse() {
debugMetricsQueue.sync {
streamedResponseCount += 1
}
}
private static func recordInMemoryResponse() {
debugMetricsQueue.sync {
inMemoryResponseCount += 1
}
}
private static func recordFailure() {
debugMetricsQueue.sync {
failureCount += 1
}
}
private static func mimeType(for pathExtension: String) -> String {
switch pathExtension.lowercased() {
case "html", "htm":
return "text/html"
case "xhtml":
return "application/xhtml+xml"
case "css":
return "text/css"
case "js":
return "application/javascript"
case "xml", "opf", "ncx":
return "application/xml"
case "svg":
return "image/svg+xml"
case "jpg", "jpeg":
return "image/jpeg"
case "png":
return "image/png"
case "gif":
return "image/gif"
case "webp":
return "image/webp"
case "ttf":
return "font/ttf"
case "otf":
return "font/otf"
case "woff":
return "font/woff"
case "woff2":
return "font/woff2"
case "mp3":
return "audio/mpeg"
case "mp4":
return "video/mp4"
default:
return "application/octet-stream"
}
}
private static func textEncodingName(for pathExtension: String) -> String? {
switch pathExtension.lowercased() {
case "html", "htm", "xhtml", "css", "js", "xml", "opf", "ncx", "txt":
return "utf-8"
default:
return nil
}
}
private static func isOptionalResource(_ url: URL) -> Bool {
switch url.pathExtension.lowercased() {
case "ttf", "otf", "woff", "woff2", "css", "js", "jpg", "jpeg", "png", "gif", "webp", "svg":
return true
default:
return false
}
}
}