passepartout-apple/PassepartoutLibrary/Sources/PassepartoutProvidersImpl/Strategies/APIRemoteProvidersStrategy....

172 lines
5.5 KiB
Swift

//
// APIRemoteProvidersStrategy.swift
// Passepartout
//
// Created by Davide De Rosa on 5/24/23.
// Copyright (c) 2023 Davide De Rosa. All rights reserved.
//
// https://github.com/passepartoutvpn
//
// This file is part of Passepartout.
//
// Passepartout is free software: you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
//
// Passepartout is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
// GNU General Public License for more details.
//
// You should have received a copy of the GNU General Public License
// along with Passepartout. If not, see <http://www.gnu.org/licenses/>.
//
import Combine
import CoreData
import Foundation
import PassepartoutCore
import PassepartoutProviders
import PassepartoutServices
public final class APIRemoteProvidersStrategy: RemoteProvidersStrategy {
private let appBuild: Int
private let bundleServices: WebServices
private let remoteServices: WebServices
private let webServicesRepository: WebServicesRepository
public init(appBuild: Int, bundleServices: WebServices, remoteServices: WebServices, webServicesRepository: WebServicesRepository) {
self.appBuild = appBuild
self.bundleServices = bundleServices
self.remoteServices = remoteServices
self.webServicesRepository = webServicesRepository
}
public func saveIndex(
priority: RemoteProvidersPriority,
onFetch: @escaping () -> Void
) -> AnyPublisher<Void, Error> {
let publisher = priority.publisher(remote: {
self.remoteServices.providersIndex()
}, bundle: {
self.bundleServices.providersIndex()
})
return publisher
.receive(on: DispatchQueue.main)
.tryMap { index in
onFetch()
try self.webServicesRepository.mergeIndex(index)
}.eraseToAnyPublisher()
}
public func saveProvider(
withName providerName: ProviderName,
vpnProtocol: VPNProtocolType,
lastUpdate: Date?,
priority: RemoteProvidersPriority,
onFetch: @escaping () -> Void
) -> AnyPublisher<Void, Error> {
let publisher = priority.publisher(remote: {
self.remoteServices.providerNetwork(
with: providerName.asWSProviderName,
vpnProtocol: vpnProtocol.asWSVPNProtocol,
ifModifiedSince: lastUpdate
)
}, bundle: {
self.bundleServices.providerNetwork(
with: providerName.asWSProviderName,
vpnProtocol: vpnProtocol.asWSVPNProtocol,
ifModifiedSince: nil
)
})
return publisher
.receive(on: DispatchQueue.main)
.flatMap { pub -> AnyPublisher<Void, Error> in
onFetch()
// ignores empty responses (e.g. HTTP 304)
guard let infrastructure = pub.value else {
return Just(())
.setFailureType(to: Error.self)
.eraseToAnyPublisher()
}
guard self.appBuild >= infrastructure.build else {
pp_log.error("Infrastructure requires app build >= \(infrastructure.build) (app is \(self.appBuild))")
return Fail(error: APIRemoteProvidersStrategyError.outdatedBuild(self.appBuild, infrastructure.build))
.eraseToAnyPublisher()
}
do {
try self.webServicesRepository.saveInfrastructure(
infrastructure,
vpnProtocol: vpnProtocol,
lastUpdate: pub.lastModified ?? Date()
)
} catch {
pp_log.error("Unable to persist \(providerName) infrastructure (\(vpnProtocol)): \(error)")
}
return Just(())
.setFailureType(to: Error.self)
.eraseToAnyPublisher()
}.eraseToAnyPublisher()
}
}
private extension RemoteProvidersPriority {
func publisher<T>(
remote: @escaping () -> AnyPublisher<T, Error>,
bundle: @escaping () -> AnyPublisher<T, Error>
) -> AnyPublisher<T, Error> {
switch self {
case .bundle:
return bundle()
case .remote:
return remote()
case .remoteThenBundle:
return remote()
.catch { error -> AnyPublisher<T, Error> in
pp_log.warning("Unable to fetch remotely: \(error)")
pp_log.warning("Falling back to bundle")
return bundle()
}.eraseToAnyPublisher()
}
}
}
private extension ProviderName {
var asWSProviderName: WSProviderName {
self
}
}
private extension VPNProtocolType {
var asWSVPNProtocol: WSVPNProtocol {
switch self {
case .openVPN:
return .openVPN
case .wireGuard:
return .wireGuard
}
}
}
private enum APIRemoteProvidersStrategyError: LocalizedError {
case outdatedBuild(Int, Int)
var errorDescription: String? {
switch self {
case .outdatedBuild(let current, let min):
return "Build is outdated (found \(current), required \(min))"
}
}
}