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Rename store.store(_:) to store.cache(_:).
This commit is contained in:
Doug
2021-09-08 09:51:47 +01:00
parent 75a9a19421
commit 5acbc20fc9
5 changed files with 64 additions and 27 deletions
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Riot/Managers/URLPreviews/URLPreviewManager.swift
+37 -5
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@@ -17,14 +17,26 @@
import Foundation
@objcMembers
/// A manager for URL preview data to handle fetching, caching and clean-up
/// as well as remembering which previews have been closed by the user.
class URLPreviewManager: NSObject {
/// The shared manager object.
static let shared = URLPreviewManager()
// Core Data store to reduce network requests
/// A persistent store backed by Core Data to reduce network requests
private let store = URLPreviewStore()
private override init() { }
/// Generates preview data for a URL to be previewed as part of the supplied event,
/// first checking the cache, and if necessary making a request to the homeserver.
/// You should call `hasClosedPreview` first to ensure that a preview is required.
/// - Parameters:
/// - url: The URL to generate the preview for.
/// - event: The event that the preview is for.
/// - session: The session to use to contact the homeserver.
/// - success: The closure called when the operation complete. The generated preview data is passed in.
/// - failure: The closure called when something goes wrong. The error that occured is passed in.
func preview(for url: URL,
and event: MXEvent,
with session: MXSession,
@@ -33,18 +45,21 @@ class URLPreviewManager: NSObject {
// Sanitize the URL before checking the store or performing lookup
let sanitizedURL = sanitize(url)
// Check for a valid preview in the store, and use this if found
if let preview = store.preview(for: sanitizedURL, and: event) {
MXLog.debug("[URLPreviewManager] Using cached preview.")
success(preview)
return
}
// Otherwise make a request to the homeserver to generate a preview
session.matrixRestClient.preview(for: sanitizedURL, success: { previewResponse in
MXLog.debug("[URLPreviewManager] Cached preview not found. Requesting from homeserver.")
if let previewResponse = previewResponse {
// Convert the response to preview data, fetching the image if provided.
self.makePreviewData(from: previewResponse, for: sanitizedURL, and: event, with: session) { previewData in
self.store.store(previewData)
self.store.cache(previewData)
success(previewData)
}
}
@@ -52,11 +67,19 @@ class URLPreviewManager: NSObject {
}, failure: failure)
}
func makePreviewData(from previewResponse: MXURLPreview,
/// Convert an `MXURLPreview` object into `URLPreviewData` whilst also getting the image via the media manager.
/// - Parameters:
/// - previewResponse: The `MXURLPreview` object to convert.
/// - url: The URL that response was for.
/// - event: The event that the URL preview is for.
/// - session: The session to use to for media management.
/// - completion: A closure called when the operation completes. This contains the preview data.
private func makePreviewData(from previewResponse: MXURLPreview,
for url: URL,
and event: MXEvent,
with session: MXSession,
completion: @escaping (URLPreviewData) -> Void) {
// Create the preview data and return if no image is needed.
let previewData = URLPreviewData(url: url,
eventID: event.eventId,
roomID: event.roomId,
@@ -69,6 +92,7 @@ class URLPreviewManager: NSObject {
return
}
// Check for an image in the media cache and use this if found.
if let cachePath = MXMediaManager.cachePath(forMatrixContentURI: imageURL, andType: previewResponse.imageType, inFolder: nil),
let image = MXMediaManager.loadThroughCache(withFilePath: cachePath) {
previewData.image = image
@@ -78,6 +102,7 @@ class URLPreviewManager: NSObject {
// Don't de-dupe image downloads as the manager should de-dupe preview generation.
// Otherwise download the image from the homeserver, treating an error as a preview without an image.
session.mediaManager.downloadMedia(fromMatrixContentURI: imageURL, withType: previewResponse.imageType, inFolder: nil) { path in
guard let image = MXMediaManager.loadThroughCache(withFilePath: path) else {
completion(previewData)
@@ -90,22 +115,29 @@ class URLPreviewManager: NSObject {
}
}
/// Removes any cached preview data that has expired.
func removeExpiredCacheData() {
store.removeExpiredItems()
}
/// Deletes all cached preview data and closed previews from the store.
func clearStore() {
store.deleteAll()
}
func closePreview(for eventID: String, in roomID: String) {
store.closePreview(for: eventID, in: roomID)
/// Store the `eventId` and `roomId` of a closed preview.
func closePreview(for eventId: String, in roomId: String) {
store.closePreview(for: eventId, in: roomId)
}
/// Whether a preview for the given event has been closed or not.
func hasClosedPreview(from event: MXEvent) -> Bool {
store.hasClosedPreview(for: event.eventId, in: event.roomId)
}
/// Returns a URL created from the URL passed in, with sanitizations applied to reduce
/// queries and duplicate cache data for URLs that will return the same preview data.
private func sanitize(_ url: URL) -> URL {
// Remove the fragment from the URL.
var components = URLComponents(url: url, resolvingAgainstBaseURL: false)