62 lines
1.5 KiB
Swift
62 lines
1.5 KiB
Swift
//
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// FeedType.swift
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// RSParser
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//
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// Created by Brent Simmons on 6/20/17.
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// Copyright © 2017 Ranchero Software, LLC. All rights reserved.
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//
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import Foundation
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public enum FeedType {
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case rss
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case atom
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case jsonFeed
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case rssInJSON
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case unknown
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case notAFeed
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}
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private let minNumberOfBytesRequired = 128
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public func feedType(_ parserData: ParserData, isPartialData: Bool = false) -> FeedType {
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// Can call with partial data — while still downloading, for instance.
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// If there’s not enough data, return .unknown. Ask again when there’s more data.
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// If it’s definitely not a feed, return .notAFeed.
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//
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// This is fast enough to call on the main thread.
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if parserData.data.count < minNumberOfBytesRequired {
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return .unknown
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}
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let nsdata = parserData.data as NSData
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if nsdata.isProbablyJSONFeed() {
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return .jsonFeed
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}
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if nsdata.isProbablyRSSInJSON() {
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return .rssInJSON
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}
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if nsdata.isProbablyRSS() {
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return .rss
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}
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if nsdata.isProbablyAtom() {
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return .atom
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}
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if isPartialData && nsdata.isProbablyJSON() {
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// Might not be able to detect a JSON Feed without all data.
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// Dr. Drang’s JSON Feed (see althis.json and allthis-partial.json in tests)
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// has, at this writing, the JSON version element at the end of the feed,
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// which is totally legal — but it means not being able to detect
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// that it’s a JSON Feed without all the data.
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// So this returns .unknown instead of .notAFeed.
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return .unknown
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}
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return .notAFeed
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}
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