NetNewsWire/Frameworks/Account/LocalAccount/LocalAccountRefresher.swift
2018-01-24 21:48:20 -08:00

140 lines
3.4 KiB
Swift

//
// LocalAccountRefresher.swift
// LocalAccount
//
// Created by Brent Simmons on 9/6/16.
// Copyright © 2016 Ranchero Software, LLC. All rights reserved.
//
import Foundation
import RSCore
import RSParser
import RSWeb
import Data
final class LocalAccountRefresher {
private lazy var downloadSession: DownloadSession = {
return DownloadSession(delegate: self)
}()
var progress: DownloadProgress {
get {
return downloadSession.progress
}
}
public func refreshFeeds(_ feeds: Set<Feed>) {
downloadSession.downloadObjects(feeds as NSSet)
}
}
// MARK: - DownloadSessionDelegate
extension LocalAccountRefresher: DownloadSessionDelegate {
func downloadSession(_ downloadSession: DownloadSession, requestForRepresentedObject representedObject: AnyObject) -> URLRequest? {
guard let feed = representedObject as? Feed else {
return nil
}
guard let url = URL(string: feed.url) else {
return nil
}
let request = NSMutableURLRequest(url: url)
if let conditionalGetInfo = feed.conditionalGetInfo {
conditionalGetInfo.addRequestHeadersToURLRequest(request)
}
return request as URLRequest
}
func downloadSession(_ downloadSession: DownloadSession, downloadDidCompleteForRepresentedObject representedObject: AnyObject, response: URLResponse?, data: Data, error: NSError?) {
guard let feed = representedObject as? Feed, !data.isEmpty else {
return
}
if let error = error {
print("Error downloading \(feed.url) - \(error)")
return
}
let dataHash = (data as NSData).rs_md5HashString()
if dataHash == feed.contentHash {
// print("Hashed content of \(feed.url) has not changed.")
return
}
let parserData = ParserData(url: feed.url, data: data)
FeedParser.parse(parserData) { (parsedFeed, error) in
guard let account = feed.account, let parsedFeed = parsedFeed, error == nil else {
return
}
account.update(feed, with: parsedFeed) {
if let httpResponse = response as? HTTPURLResponse {
feed.conditionalGetInfo = HTTPConditionalGetInfo(urlResponse: httpResponse)
}
feed.contentHash = dataHash
feed.account?.dirty = true
}
}
}
func downloadSession(_ downloadSession: DownloadSession, shouldContinueAfterReceivingData data: Data, representedObject: AnyObject) -> Bool {
guard let feed = representedObject as? Feed else {
return false
}
if data.isEmpty {
return true
}
if data.isDefinitelyNotFeed() {
return false
}
if data.count > 4096 {
let parserData = ParserData(url: feed.url, data: data)
return FeedParser.mightBeAbleToParseBasedOnPartialData(parserData)
}
return true
}
func downloadSession(_ downloadSession: DownloadSession, didReceiveUnexpectedResponse response: URLResponse, representedObject: AnyObject) {
// guard let feed = representedObject as? Feed else {
// return
// }
//
// print("Unexpected response \(response) for \(feed.url).")
}
func downloadSession(_ downloadSession: DownloadSession, didReceiveNotModifiedResponse: URLResponse, representedObject: AnyObject) {
// guard let feed = representedObject as? Feed else {
// return
// }
//
// print("Not modified response for \(feed.url).")
}
}
// MARK: - Utility
private extension Data {
func isDefinitelyNotFeed() -> Bool {
// We only detect a few image types for now. This should get fleshed-out at some later date.
return (self as NSData).rs_dataIsImage()
}
}