NetNewsWire/Frameworks/ArticlesDatabase/ArticlesTable.swift
2019-07-08 21:09:54 -07:00

741 lines
27 KiB
Swift
Raw Blame History

This file contains ambiguous Unicode characters

This file contains Unicode characters that might be confused with other characters. If you think that this is intentional, you can safely ignore this warning. Use the Escape button to reveal them.

//
// ArticlesTable.swift
// NetNewsWire
//
// Created by Brent Simmons on 5/9/16.
// Copyright © 2016 Ranchero Software, LLC. All rights reserved.
//
import Foundation
import RSCore
import RSDatabase
import RSParser
import Articles
final class ArticlesTable: DatabaseTable {
let name: String
private let accountID: String
private let queue: RSDatabaseQueue
private let statusesTable: StatusesTable
private let authorsLookupTable: DatabaseLookupTable
private let attachmentsLookupTable: DatabaseLookupTable
private lazy var searchTable: SearchTable = {
return SearchTable(queue: queue, articlesTable: self)
}()
// TODO: update articleCutoffDate as time passes and based on user preferences.
private var articleCutoffDate = NSDate.rs_dateWithNumberOfDays(inThePast: 3 * 31)!
private var maximumArticleCutoffDate = NSDate.rs_dateWithNumberOfDays(inThePast: 4 * 31)!
private typealias ArticlesFetchMethod = (FMDatabase) -> Set<Article>
init(name: String, accountID: String, queue: RSDatabaseQueue) {
self.name = name
self.accountID = accountID
self.queue = queue
self.statusesTable = StatusesTable(queue: queue)
let authorsTable = AuthorsTable(name: DatabaseTableName.authors)
self.authorsLookupTable = DatabaseLookupTable(name: DatabaseTableName.authorsLookup, objectIDKey: DatabaseKey.articleID, relatedObjectIDKey: DatabaseKey.authorID, relatedTable: authorsTable, relationshipName: RelationshipName.authors)
let attachmentsTable = AttachmentsTable(name: DatabaseTableName.attachments)
self.attachmentsLookupTable = DatabaseLookupTable(name: DatabaseTableName.attachmentsLookup, objectIDKey: DatabaseKey.articleID, relatedObjectIDKey: DatabaseKey.attachmentID, relatedTable: attachmentsTable, relationshipName: RelationshipName.attachments)
}
// MARK: - Fetch Articles for Feed
func fetchArticles(_ feedID: String) -> Set<Article> {
return fetchArticles{ self.fetchArticlesForFeedID(feedID, withLimits: true, $0) }
}
func fetchArticlesAsync(_ feedID: String, _ callback: @escaping ArticleSetBlock) {
fetchArticlesAsync({ self.fetchArticlesForFeedID(feedID, withLimits: true, $0) }, callback)
}
private func fetchArticlesForFeedID(_ feedID: String, withLimits: Bool, _ database: FMDatabase) -> Set<Article> {
return fetchArticlesWithWhereClause(database, whereClause: "articles.feedID = ?", parameters: [feedID as AnyObject], withLimits: withLimits)
}
// MARK: - Fetch Articles by articleID
func fetchArticles(articleIDs: Set<String>) -> Set<Article> {
return fetchArticles{ self.fetchArticles(articleIDs: articleIDs, $0) }
}
func fetchArticlesAsync(articleIDs: Set<String>, _ callback: @escaping ArticleSetBlock) {
return fetchArticlesAsync({ self.fetchArticles(articleIDs: articleIDs, $0) }, callback)
}
private func fetchArticles(articleIDs: Set<String>, _ database: FMDatabase) -> Set<Article> {
if articleIDs.isEmpty {
return Set<Article>()
}
let parameters = articleIDs.map { $0 as AnyObject }
let placeholders = NSString.rs_SQLValueList(withPlaceholders: UInt(articleIDs.count))!
let whereClause = "articleID in \(placeholders)"
return fetchArticlesWithWhereClause(database, whereClause: whereClause, parameters: parameters, withLimits: false)
}
// MARK: - Fetch Unread Articles
func fetchUnreadArticles(_ feedIDs: Set<String>) -> Set<Article> {
return fetchArticles{ self.fetchUnreadArticles(feedIDs, $0) }
}
func fetchUnreadArticlesAsync(_ feedIDs: Set<String>, _ callback: @escaping ArticleSetBlock) {
fetchArticlesAsync({ self.fetchUnreadArticles(feedIDs, $0) }, callback)
}
private func fetchUnreadArticles(_ feedIDs: Set<String>, _ database: FMDatabase) -> Set<Article> {
// select * from articles natural join statuses where feedID in ('http://ranchero.com/xml/rss.xml') and read=0
if feedIDs.isEmpty {
return Set<Article>()
}
let parameters = feedIDs.map { $0 as AnyObject }
let placeholders = NSString.rs_SQLValueList(withPlaceholders: UInt(feedIDs.count))!
let whereClause = "feedID in \(placeholders) and read=0"
return fetchArticlesWithWhereClause(database, whereClause: whereClause, parameters: parameters, withLimits: true)
}
// MARK: - Fetch Today Articles
func fetchTodayArticles(_ feedIDs: Set<String>) -> Set<Article> {
return fetchArticles{ self.fetchTodayArticles(feedIDs, $0) }
}
func fetchTodayArticlesAsync(_ feedIDs: Set<String>, _ callback: @escaping ArticleSetBlock) {
fetchArticlesAsync({ self.fetchTodayArticles(feedIDs, $0) }, callback)
}
private func fetchTodayArticles(_ feedIDs: Set<String>, _ database: FMDatabase) -> Set<Article> {
// select * from articles natural join statuses where feedID in ('http://ranchero.com/xml/rss.xml') and (datePublished > ? || (datePublished is null and dateArrived > ?)
//
// datePublished may be nil, so we fall back to dateArrived.
if feedIDs.isEmpty {
return Set<Article>()
}
let startOfToday = NSCalendar.startOfToday()
let parameters = feedIDs.map { $0 as AnyObject } + [startOfToday as AnyObject, startOfToday as AnyObject]
let placeholders = NSString.rs_SQLValueList(withPlaceholders: UInt(feedIDs.count))!
let whereClause = "feedID in \(placeholders) and (datePublished > ? or (datePublished is null and dateArrived > ?)) and userDeleted = 0"
return fetchArticlesWithWhereClause(database, whereClause: whereClause, parameters: parameters, withLimits: false)
}
// MARK: - Fetch Starred Articles
func fetchStarredArticles(_ feedIDs: Set<String>) -> Set<Article> {
return fetchArticles{ self.fetchStarredArticles(feedIDs, $0) }
}
func fetchStarredArticlesAsync(_ feedIDs: Set<String>, _ callback: @escaping ArticleSetBlock) {
fetchArticlesAsync({ self.fetchStarredArticles(feedIDs, $0) }, callback)
}
private func fetchStarredArticles(_ feedIDs: Set<String>, _ database: FMDatabase) -> Set<Article> {
// select * from articles natural join statuses where feedID in ('http://ranchero.com/xml/rss.xml') and starred = 1 and userDeleted = 0;
if feedIDs.isEmpty {
return Set<Article>()
}
let parameters = feedIDs.map { $0 as AnyObject }
let placeholders = NSString.rs_SQLValueList(withPlaceholders: UInt(feedIDs.count))!
let whereClause = "feedID in \(placeholders) and starred = 1 and userDeleted = 0"
return fetchArticlesWithWhereClause(database, whereClause: whereClause, parameters: parameters, withLimits: false)
}
// MARK: - Fetch Search Articles
func fetchArticlesMatching(_ searchString: String, _ feedIDs: Set<String>) -> Set<Article> {
var articles: Set<Article> = Set<Article>()
queue.fetchSync { (database) in
articles = self.fetchArticlesMatching(searchString, database)
}
articles = articles.filter{ feedIDs.contains($0.feedID) }
return articles
}
func fetchArticlesMatchingAsync(_ searchString: String, _ feedIDs: Set<String>, _ callback: @escaping ArticleSetBlock) {
fetchArticlesAsync({ self.fetchArticlesMatching(searchString, feedIDs, $0) }, callback)
}
private func fetchArticlesMatching(_ searchString: String, _ feedIDs: Set<String>, _ database: FMDatabase) -> Set<Article> {
let sql = "select rowid from search where search match ?;"
let sqlSearchString = sqliteSearchString(with: searchString)
let searchStringParameters = [sqlSearchString]
guard let resultSet = database.executeQuery(sql, withArgumentsIn: searchStringParameters) else {
return Set<Article>()
}
let searchRowIDs = resultSet.mapToSet { $0.longLongInt(forColumnIndex: 0) }
if searchRowIDs.isEmpty {
return Set<Article>()
}
let placeholders = NSString.rs_SQLValueList(withPlaceholders: UInt(searchRowIDs.count))!
let whereClause = "searchRowID in \(placeholders)"
let parameters: [AnyObject] = Array(searchRowIDs) as [AnyObject]
let articles = fetchArticlesWithWhereClause(database, whereClause: whereClause, parameters: parameters, withLimits: true)
// TODO: include the feedIDs in the SQL rather than filtering here.
return articles.filter{ feedIDs.contains($0.feedID) }
}
// MARK: - Fetch Articles for Indexer
func fetchArticleSearchInfos(_ articleIDs: Set<String>, in database: FMDatabase) -> Set<ArticleSearchInfo>? {
let parameters = articleIDs.map { $0 as AnyObject }
let placeholders = NSString.rs_SQLValueList(withPlaceholders: UInt(articleIDs.count))!
let sql = "select articleID, title, contentHTML, contentText, summary, searchRowID from articles where articleID in \(placeholders);";
if let resultSet = database.executeQuery(sql, withArgumentsIn: parameters) {
return resultSet.mapToSet { (row) -> ArticleSearchInfo? in
let articleID = row.string(forColumn: DatabaseKey.articleID)!
let title = row.string(forColumn: DatabaseKey.title)
let contentHTML = row.string(forColumn: DatabaseKey.contentHTML)
let contentText = row.string(forColumn: DatabaseKey.contentText)
let summary = row.string(forColumn: DatabaseKey.summary)
let searchRowIDObject = row.object(forColumnName: DatabaseKey.searchRowID)
var searchRowID: Int? = nil
if searchRowIDObject != nil && !(searchRowIDObject is NSNull) {
searchRowID = Int(row.longLongInt(forColumn: DatabaseKey.searchRowID))
}
return ArticleSearchInfo(articleID: articleID, title: title, contentHTML: contentHTML, contentText: contentText, summary: summary, searchRowID: searchRowID)
}
}
return nil
}
// MARK: Updating
func update(_ feedID: String, _ parsedItems: Set<ParsedItem>, _ read: Bool, _ completion: @escaping UpdateArticlesWithFeedCompletionBlock) {
if parsedItems.isEmpty {
completion(nil, nil)
return
}
// 1. Ensure statuses for all the incoming articles.
// 2. Create incoming articles with parsedItems.
// 3. Ignore incoming articles that are userDeleted || (!starred and really old)
// 4. Fetch all articles for the feed.
// 5. Create array of Articles not in database and save them.
// 6. Create array of updated Articles and save whats changed.
// 7. Call back with new and updated Articles.
// 8. Update search index.
let articleIDs = Set(parsedItems.map { $0.articleID })
self.queue.update { (database) in
let statusesDictionary = self.statusesTable.ensureStatusesForArticleIDs(articleIDs, read, database) //1
assert(statusesDictionary.count == articleIDs.count)
let allIncomingArticles = Article.articlesWithParsedItems(parsedItems, self.accountID, feedID, statusesDictionary) //2
if allIncomingArticles.isEmpty {
self.callUpdateArticlesCompletionBlock(nil, nil, completion)
return
}
let incomingArticles = self.filterIncomingArticles(allIncomingArticles) //3
if incomingArticles.isEmpty {
self.callUpdateArticlesCompletionBlock(nil, nil, completion)
return
}
let fetchedArticles = self.fetchArticlesForFeedID(feedID, withLimits: false, database) //4
let fetchedArticlesDictionary = fetchedArticles.dictionary()
let newArticles = self.findAndSaveNewArticles(incomingArticles, fetchedArticlesDictionary, database) //5
let updatedArticles = self.findAndSaveUpdatedArticles(incomingArticles, fetchedArticlesDictionary, database) //6
self.callUpdateArticlesCompletionBlock(newArticles, updatedArticles, completion) //7
// 8. Update search index.
var articlesToIndex = Set<Article>()
if let newArticles = newArticles {
articlesToIndex.formUnion(newArticles)
}
if let updatedArticles = updatedArticles {
articlesToIndex.formUnion(updatedArticles)
}
let articleIDs = articlesToIndex.articleIDs()
if articleIDs.isEmpty {
return
}
DispatchQueue.main.async() {
self.searchTable.ensureIndexedArticles(for: articleIDs)
}
}
}
func ensureStatuses(_ articleIDs: Set<String>, _ statusKey: ArticleStatus.Key, _ flag: Bool) {
self.queue.update { (database) in
let statusesDictionary = self.statusesTable.ensureStatusesForArticleIDs(articleIDs, false, database)
let statuses = Set(statusesDictionary.values)
self.statusesTable.mark(statuses, statusKey, flag, database)
}
}
// MARK: Unread Counts
func fetchUnreadCounts(_ feedIDs: Set<String>, _ completion: @escaping UnreadCountCompletionBlock) {
if feedIDs.isEmpty {
completion(UnreadCountDictionary())
return
}
var unreadCountDictionary = UnreadCountDictionary()
queue.fetch { (database) in
for feedID in feedIDs {
unreadCountDictionary[feedID] = self.fetchUnreadCount(feedID, database)
}
DispatchQueue.main.async() {
completion(unreadCountDictionary)
}
}
}
func fetchUnreadCount(_ feedIDs: Set<String>, _ since: Date, _ callback: @escaping (Int) -> Void) {
// Get unread count for today, for instance.
if feedIDs.isEmpty {
callback(0)
return
}
queue.fetch { (database) in
let placeholders = NSString.rs_SQLValueList(withPlaceholders: UInt(feedIDs.count))!
let sql = "select count(*) from articles natural join statuses where feedID in \(placeholders) and (datePublished > ? or (datePublished is null and dateArrived > ?)) and read=0 and userDeleted=0;"
var parameters = [Any]()
parameters += Array(feedIDs) as [Any]
parameters += [since] as [Any]
parameters += [since] as [Any]
let unreadCount = self.numberWithSQLAndParameters(sql, parameters, in: database)
DispatchQueue.main.async() {
callback(unreadCount)
}
}
}
func fetchAllUnreadCounts(_ completion: @escaping UnreadCountCompletionBlock) {
// Returns only where unreadCount > 0.
let cutoffDate = articleCutoffDate
queue.fetch { (database) in
let sql = "select distinct feedID, count(*) from articles natural join statuses where read=0 and userDeleted=0 and (starred=1 or dateArrived>?) group by feedID;"
guard let resultSet = database.executeQuery(sql, withArgumentsIn: [cutoffDate]) else {
DispatchQueue.main.async() {
completion(UnreadCountDictionary())
}
return
}
var d = UnreadCountDictionary()
while resultSet.next() {
let unreadCount = resultSet.long(forColumnIndex: 1)
if let feedID = resultSet.string(forColumnIndex: 0) {
d[feedID] = unreadCount
}
}
DispatchQueue.main.async() {
completion(d)
}
}
}
func fetchStarredAndUnreadCount(_ feedIDs: Set<String>, _ callback: @escaping (Int) -> Void) {
if feedIDs.isEmpty {
callback(0)
return
}
queue.fetch { (database) in
let placeholders = NSString.rs_SQLValueList(withPlaceholders: UInt(feedIDs.count))!
let sql = "select count(*) from articles natural join statuses where feedID in \(placeholders) and read=0 and starred=1 and userDeleted=0;"
let parameters = Array(feedIDs) as [Any]
let unreadCount = self.numberWithSQLAndParameters(sql, parameters, in: database)
DispatchQueue.main.async() {
callback(unreadCount)
}
}
}
// MARK: Status
func fetchUnreadArticleIDs(_ callback: @escaping (Set<String>) -> Void) {
statusesTable.fetchUnreadArticleIDs(callback)
}
func fetchStarredArticleIDs(_ callback: @escaping (Set<String>) -> Void) {
statusesTable.fetchStarredArticleIDs(callback)
}
func fetchArticleIDsForStatusesWithoutArticles(_ callback: @escaping (Set<String>) -> Void) {
statusesTable.fetchArticleIDsForStatusesWithoutArticles(callback)
}
func mark(_ articles: Set<Article>, _ statusKey: ArticleStatus.Key, _ flag: Bool) -> Set<ArticleStatus>? {
var statuses: Set<ArticleStatus>?
self.queue.updateSync { (database) in
statuses = self.statusesTable.mark(articles.statuses(), statusKey, flag, database)
}
return statuses
}
// MARK: Indexing
func indexUnindexedArticles() {
queue.fetch { (database) in
let sql = "select articleID from articles where searchRowID is null limit 500;"
guard let resultSet = database.executeQuery(sql, withArgumentsIn: nil) else {
return
}
let articleIDs = resultSet.mapToSet{ $0.string(forColumn: DatabaseKey.articleID) }
if articleIDs.isEmpty {
return
}
self.searchTable.ensureIndexedArticles(for: articleIDs)
DispatchQueue.main.async {
self.indexUnindexedArticles()
}
}
}
}
// MARK: - Private
private extension ArticlesTable {
// MARK: Fetching
private func fetchArticles(_ fetchMethod: @escaping ArticlesFetchMethod) -> Set<Article> {
var articles = Set<Article>()
queue.fetchSync { (database) in
articles = fetchMethod(database)
}
return articles
}
private func fetchArticlesAsync(_ fetchMethod: @escaping ArticlesFetchMethod, _ callback: @escaping ArticleSetBlock) {
queue.fetch { (database) in
let articles = fetchMethod(database)
DispatchQueue.main.async {
callback(articles)
}
}
}
func articlesWithResultSet(_ resultSet: FMResultSet, _ database: FMDatabase) -> Set<Article> {
// 1. Create DatabaseArticles without related objects.
// 2. Then fetch the related objects, given the set of articleIDs.
// 3. Then create set of Articles with DatabaseArticles and related objects and return it.
// 1. Create databaseArticles (intermediate representations).
let databaseArticles = makeDatabaseArticles(with: resultSet)
if databaseArticles.isEmpty {
return Set<Article>()
}
let articleIDs = databaseArticles.articleIDs()
// 2. Fetch related objects.
let authorsMap = authorsLookupTable.fetchRelatedObjects(for: articleIDs, in: database)
let attachmentsMap = attachmentsLookupTable.fetchRelatedObjects(for: articleIDs, in: database)
// 3. Create articles with related objects.
let articles = databaseArticles.map { (databaseArticle) -> Article in
return articleWithDatabaseArticle(databaseArticle, authorsMap, attachmentsMap)
}
return Set(articles)
}
func articleWithDatabaseArticle(_ databaseArticle: DatabaseArticle, _ authorsMap: RelatedObjectsMap?, _ attachmentsMap: RelatedObjectsMap?) -> Article {
let articleID = databaseArticle.articleID
let authors = authorsMap?.authors(for: articleID)
let attachments = attachmentsMap?.attachments(for: articleID)
return Article(databaseArticle: databaseArticle, accountID: accountID, authors: authors, attachments: attachments)
}
func makeDatabaseArticles(with resultSet: FMResultSet) -> Set<DatabaseArticle> {
let articles = resultSet.mapToSet { (row) -> DatabaseArticle? in
// The resultSet is a result of a JOIN query with the statuses table,
// so we can get the statuses at the same time and avoid additional database lookups.
guard let status = statusesTable.statusWithRow(resultSet) else {
assertionFailure("Expected status.")
return nil
}
guard let articleID = row.string(forColumn: DatabaseKey.articleID) else {
assertionFailure("Expected articleID.")
return nil
}
guard let feedID = row.string(forColumn: DatabaseKey.feedID) else {
assertionFailure("Expected feedID.")
return nil
}
guard let uniqueID = row.string(forColumn: DatabaseKey.uniqueID) else {
assertionFailure("Expected uniqueID.")
return nil
}
let title = row.string(forColumn: DatabaseKey.title)
let contentHTML = row.string(forColumn: DatabaseKey.contentHTML)
let contentText = row.string(forColumn: DatabaseKey.contentText)
let url = row.string(forColumn: DatabaseKey.url)
let externalURL = row.string(forColumn: DatabaseKey.externalURL)
let summary = row.string(forColumn: DatabaseKey.summary)
let imageURL = row.string(forColumn: DatabaseKey.imageURL)
let bannerImageURL = row.string(forColumn: DatabaseKey.bannerImageURL)
let datePublished = row.date(forColumn: DatabaseKey.datePublished)
let dateModified = row.date(forColumn: DatabaseKey.dateModified)
return DatabaseArticle(articleID: articleID, feedID: feedID, uniqueID: uniqueID, title: title, contentHTML: contentHTML, contentText: contentText, url: url, externalURL: externalURL, summary: summary, imageURL: imageURL, bannerImageURL: bannerImageURL, datePublished: datePublished, dateModified: dateModified, status: status)
}
return articles
}
func fetchArticlesWithWhereClause(_ database: FMDatabase, whereClause: String, parameters: [AnyObject], withLimits: Bool) -> Set<Article> {
// Dont fetch articles that shouldnt appear in the UI. The rules:
// * Must not be deleted.
// * Must be either 1) starred or 2) dateArrived must be newer than cutoff date.
if withLimits {
let sql = "select * from articles natural join statuses where \(whereClause) and userDeleted=0 and (starred=1 or dateArrived>?);"
return articlesWithSQL(sql, parameters + [articleCutoffDate as AnyObject], database)
}
else {
let sql = "select * from articles natural join statuses where \(whereClause);"
return articlesWithSQL(sql, parameters, database)
}
}
func fetchUnreadCount(_ feedID: String, _ database: FMDatabase) -> Int {
// Count only the articles that would appear in the UI.
// * Must be unread.
// * Must not be deleted.
// * Must be either 1) starred or 2) dateArrived must be newer than cutoff date.
let sql = "select count(*) from articles natural join statuses where feedID=? and read=0 and userDeleted=0 and (starred=1 or dateArrived>?);"
return numberWithSQLAndParameters(sql, [feedID, articleCutoffDate], in: database)
}
func fetchArticlesMatching(_ searchString: String, _ database: FMDatabase) -> Set<Article> {
let sql = "select rowid from search where search match ?;"
let sqlSearchString = sqliteSearchString(with: searchString)
let searchStringParameters = [sqlSearchString]
guard let resultSet = database.executeQuery(sql, withArgumentsIn: searchStringParameters) else {
return Set<Article>()
}
let searchRowIDs = resultSet.mapToSet { $0.longLongInt(forColumnIndex: 0) }
if searchRowIDs.isEmpty {
return Set<Article>()
}
let placeholders = NSString.rs_SQLValueList(withPlaceholders: UInt(searchRowIDs.count))!
let whereClause = "searchRowID in \(placeholders)"
let parameters: [AnyObject] = Array(searchRowIDs) as [AnyObject]
return fetchArticlesWithWhereClause(database, whereClause: whereClause, parameters: parameters, withLimits: true)
}
func sqliteSearchString(with searchString: String) -> String {
var s = ""
searchString.enumerateSubstrings(in: searchString.startIndex..<searchString.endIndex, options: .byWords) { (word, range, enclosingRange, stop) in
guard let word = word else {
return
}
s += word
if s != "AND" && s != "OR" {
s += "*"
}
s += " "
}
return s
}
func articlesWithSQL(_ sql: String, _ parameters: [AnyObject], _ database: FMDatabase) -> Set<Article> {
guard let resultSet = database.executeQuery(sql, withArgumentsIn: parameters) else {
return Set<Article>()
}
return articlesWithResultSet(resultSet, database)
}
// MARK: Saving Parsed Items
func callUpdateArticlesCompletionBlock(_ newArticles: Set<Article>?, _ updatedArticles: Set<Article>?, _ completion: @escaping UpdateArticlesWithFeedCompletionBlock) {
DispatchQueue.main.async {
completion(newArticles, updatedArticles)
}
}
// MARK: Save New Articles
func findNewArticles(_ incomingArticles: Set<Article>, _ fetchedArticlesDictionary: [String: Article]) -> Set<Article>? {
let newArticles = Set(incomingArticles.filter { fetchedArticlesDictionary[$0.articleID] == nil })
return newArticles.isEmpty ? nil : newArticles
}
func findAndSaveNewArticles(_ incomingArticles: Set<Article>, _ fetchedArticlesDictionary: [String: Article], _ database: FMDatabase) -> Set<Article>? { //5
guard let newArticles = findNewArticles(incomingArticles, fetchedArticlesDictionary) else {
return nil
}
self.saveNewArticles(newArticles, database)
return newArticles
}
func saveNewArticles(_ articles: Set<Article>, _ database: FMDatabase) {
saveRelatedObjectsForNewArticles(articles, database)
if let databaseDictionaries = articles.databaseDictionaries() {
insertRows(databaseDictionaries, insertType: .orReplace, in: database)
}
}
func saveRelatedObjectsForNewArticles(_ articles: Set<Article>, _ database: FMDatabase) {
let databaseObjects = articles.databaseObjects()
authorsLookupTable.saveRelatedObjects(for: databaseObjects, in: database)
attachmentsLookupTable.saveRelatedObjects(for: databaseObjects, in: database)
}
// MARK: Update Existing Articles
func articlesWithRelatedObjectChanges<T>(_ comparisonKeyPath: KeyPath<Article, Set<T>?>, _ updatedArticles: Set<Article>, _ fetchedArticles: [String: Article]) -> Set<Article> {
return updatedArticles.filter{ (updatedArticle) -> Bool in
if let fetchedArticle = fetchedArticles[updatedArticle.articleID] {
return updatedArticle[keyPath: comparisonKeyPath] != fetchedArticle[keyPath: comparisonKeyPath]
}
assertionFailure("Expected to find matching fetched article.");
return true
}
}
func updateRelatedObjects<T>(_ comparisonKeyPath: KeyPath<Article, Set<T>?>, _ updatedArticles: Set<Article>, _ fetchedArticles: [String: Article], _ lookupTable: DatabaseLookupTable, _ database: FMDatabase) {
let articlesWithChanges = articlesWithRelatedObjectChanges(comparisonKeyPath, updatedArticles, fetchedArticles)
if !articlesWithChanges.isEmpty {
lookupTable.saveRelatedObjects(for: articlesWithChanges.databaseObjects(), in: database)
}
}
func saveUpdatedRelatedObjects(_ updatedArticles: Set<Article>, _ fetchedArticles: [String: Article], _ database: FMDatabase) {
updateRelatedObjects(\Article.authors, updatedArticles, fetchedArticles, authorsLookupTable, database)
updateRelatedObjects(\Article.attachments, updatedArticles, fetchedArticles, attachmentsLookupTable, database)
}
func findUpdatedArticles(_ incomingArticles: Set<Article>, _ fetchedArticlesDictionary: [String: Article]) -> Set<Article>? {
let updatedArticles = incomingArticles.filter{ (incomingArticle) -> Bool in //6
if let existingArticle = fetchedArticlesDictionary[incomingArticle.articleID] {
if existingArticle != incomingArticle {
return true
}
}
return false
}
return updatedArticles.isEmpty ? nil : updatedArticles
}
func findAndSaveUpdatedArticles(_ incomingArticles: Set<Article>, _ fetchedArticlesDictionary: [String: Article], _ database: FMDatabase) -> Set<Article>? { //6
guard let updatedArticles = findUpdatedArticles(incomingArticles, fetchedArticlesDictionary) else {
return nil
}
saveUpdatedArticles(Set(updatedArticles), fetchedArticlesDictionary, database)
return updatedArticles
}
func saveUpdatedArticles(_ updatedArticles: Set<Article>, _ fetchedArticles: [String: Article], _ database: FMDatabase) {
saveUpdatedRelatedObjects(updatedArticles, fetchedArticles, database)
for updatedArticle in updatedArticles {
saveUpdatedArticle(updatedArticle, fetchedArticles, database)
}
}
func saveUpdatedArticle(_ updatedArticle: Article, _ fetchedArticles: [String: Article], _ database: FMDatabase) {
// Only update exactly what has changed in the Article (if anything).
// Untested theory: this gets us better performance and less database fragmentation.
guard let fetchedArticle = fetchedArticles[updatedArticle.articleID] else {
assertionFailure("Expected to find matching fetched article.");
saveNewArticles(Set([updatedArticle]), database)
return
}
guard let changesDictionary = updatedArticle.changesFrom(fetchedArticle), changesDictionary.count > 0 else {
// Not unexpected. There may be no changes.
return
}
updateRowsWithDictionary(changesDictionary, whereKey: DatabaseKey.articleID, matches: updatedArticle.articleID, database: database)
}
func statusIndicatesArticleIsIgnorable(_ status: ArticleStatus) -> Bool {
// Ignorable articles: either userDeleted==1 or (not starred and arrival date > 4 months).
if status.userDeleted {
return true
}
if status.starred {
return false
}
return status.dateArrived < maximumArticleCutoffDate
}
func filterIncomingArticles(_ articles: Set<Article>) -> Set<Article> {
// Drop Articles that we can ignore.
return Set(articles.filter{ !statusIndicatesArticleIsIgnorable($0.status) })
}
}