It's not uncommon for developers to make data structures that they want to store on disk conform to Codable so they can easily convert their objects to Data, which can then be written to a file on the file system. Documents that the user creates like text files or PDFs are also typically stored on disk if possible. These kinds of files are known as binary data and they have no properties that you might want to query in a database for example. For example images, videos or large JSON files are suited to be stored on disk. Typically, you will use disk storage for larger amounts of data. As with everything, this is a tradeoff and only by measuring and testing will you know whether you need something quicker than disk access, like for instance an SQLite store or in-memory storage. The file system typically has a large amount of storage available, but it can be relatively slow to read large amounts of data from. If this is the case, you might want to look into storing files on the user’s file system. ![]() Sometimes you need more than the limited storage user defaults gives you. Especially if they’re quite long or complex like they are in the example that you just read. Note that you might want to use Swift 5’s powerful property wrappers or a wrapper around UserDefaults to make accessing your user defaults a little bit cleaner since it’s easy to make mistakes while typing your user defaults keys. Let isUserAwesome = myDefaults?.bool(forKey: "-is-awesome") ![]() MyDefaults?.set(true, forKey: "-is-awesome") You can create and use your own user defaults store as follows: let myDefaults = UserDefaults(suiteName: "") This means that you don't have to access the underlying disk storage at all to retrieve values using the UserDefaults class. Reading from user defaults is really fast because your app's preferences are loaded into memory when your app launches. I always recommend the latter since it makes it somewhat easier to swap your user defaults store out for a different one and it allows you to separate your own user defaults from those that can be accessed by external dependencies that you might include in your app. You can use the default user store that is always available to your app, or you can create your own user defaults store with its own unique identifier. If you wish to use the user defaults store, you do so through the UserDefaults class. However, a user’s email address, password and other, similar data, should be stored somewhere more secure. This storage is not encrypted at all so if an app other than your own obtains access to your user defaults store, your user’s data is compromised.įor example, simple preferences that can’t be used to identify your users are okay to store in user defaults. You should never store any sensitive data in user defaults. Anything larger will fill up your store rapidly. This amount of storage is a lot of you only store simple data like booleans, numbers or strings because they're small and very well-suited for key-value storage. On tvOS, the user defaults store is even limited to a maximum 1MB of data and Apple recommends not exceeding 512KB. You can store a fairly large amount of data in user defaults but it’s not encouraged to store large blobs of data, images and other large data structures in user defaults. In my blog post on optimizing your app’s App Store reviews, user defaults are used to track several metrics like the number of launches, when the user first launched the app and more to figure out the best moment to show the user a review prompt. ![]() You typically use this storage for simple user preferences or to store simple values that help improve the user’s experience. Possibly the most well-known, easiest to use storage on iOS is the user defaults store. With that disclaimer out of the way, let’s start exploring storage options on iOS, shall we? Utilizing UserDefaults storage In general, you should at least consider any data that you store on a device accessible by attackers that have access to a physical device. I won’t cover how you can best encrypt data to increase security for any of the listed storage mechanisms. For this reason, I will only cover every storage mechanism in its “normal”, basic usage. Please note that I am not a security or encryption expert. In this post, you will learn about the following storage mechanisms: In this week’s blog post I will show you several storage options that are available to you as an iOS developer, and I'll explain the pros and cons of every storage method.
0 Comments
Leave a Reply. |
AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |