Signal-iOS/SignalServiceKit/Util/Error+IsRetryable.swift
2026-05-22 15:39:21 -05:00

75 lines
2.0 KiB
Swift

//
// Copyright 2021 Signal Messenger, LLC
// SPDX-License-Identifier: AGPL-3.0-only
//
import Foundation
public import LibSignalClient
import ObjectiveC
extension Error {
public var isRetryable: Bool {
// Error and NSError have a special relationship.
// They can be "cast" back and forth, but are separate objects.
//
// If Error is cast to NSError, a new NSError will wrap the Error.
// This is called "NSError bridging".
//
// NSError implements Error protocol, but casting NSError to Error
// might unwrap a bridged wrapper.
//
// If you roundtrip-cast Error to NSError and back (or vice versa),
// you should not count on ending up with the same as instance as
// you began with, even though you sometimes will.
//
// When trying to cast an error to IsRetryableProvider,
// we need to try casting both the Error and NSError form.
if let error = self as? IsRetryableProvider, error.isRetryableProvider {
return true
}
if let error = (self as NSError) as? IsRetryableProvider, error.isRetryableProvider {
return true
}
if self.isNetworkFailureOrTimeout {
// We can safely default to retrying network failures.
return true
}
return false
}
}
// MARK: -
public protocol IsRetryableProvider {
var isRetryableProvider: Bool { get }
}
// MARK: -
// NOTE: We typically prefer to use a more specific error.
public class OWSRetryableError: CustomNSError, IsRetryableProvider {
public static var asNSError: NSError {
OWSRetryableError() as Error as NSError
}
public init() {
}
// MARK: - IsRetryableProvider
public var isRetryableProvider: Bool { true }
}
// MARK: - SignalError
extension SignalError: IsRetryableProvider {
public var isRetryableProvider: Bool {
switch self {
case .mismatchedDevices: return true
default: return false
}
}
}