DeviantArtFs 8.0.0

DeviantArtFs

A .NET / F# library to interact with the DeviantArt / Sta.sh API.

Design

Each request that can be made to DeviantArt is represented by a function in one of the modules (static classes) in the DeviantArtFs.Api namespace. Each static method takes an IDeviantArtAccessToken as its first parameter. Most methods have additional parameters, many of which are discriminated unions in the DeviantArtFs.ParameterTypes namespace; hopefully this makes it easy to see exactly what your code is doing and ensures that parameters can't get mixed up.

In some cases, two methods are available for an API call. Functions whose names begin with Page will return a single page of results, while the corresponding Get function will return an asynchronous sequence which begins at the offset you specify (see "Interoperability" below). Be careful not to request too much data or you might hit API usage limits.

Interoperability

In order to maximize ease of use from within F#, the response objects in this library are .NET records using F# option types to represent missing fields. This means that you will need extension methods (see below) to extract a null value or another placeholder value from these fields.

Since these extension methods are required to use the library outside F#, I've also decided to reduce the amount of duplicate code in the library by exposing Async<T> directly and relying on C# and VB.NET consumers to use another extension method to create a Task<T>. This has the additional benefit of (hopefully) allowing the consumer to pass a cancellation token to any method; let me know if there are any bugs in this regard.

The following types are used in response objects:

• FSharpAsync<T>: An F# asynchronous workflow. An extension method (see below) allows C# or VB.NET users to create a Task<T> that can be awaited.
• IAsyncEnumerable<T>: A .NET asynchronous enumerable. F# users can use FSharp.Control.AsyncSeq and its ofAsyncEnum function to create an AsyncSeq<T>, while C# users can use the extension methods in the NuGet package System.Linq.Async or consume the enumerable directly with await foreach.
• FSharpOption<T>: Used to represent fields that may be missing or null on the response object. Extension methods (see below) allow C# and VB.NET users to extract these values by converting None to null or to an empty list.
• FSharpList<T>: An immutable linked list. Implements IReadOnlyList<T> and IEnumerable<T>, so other .NET languages can use foreach, LINQ, or access the list's properties directly.

The following extension methods are provided in the namespace DeviantArtFs.Extensions:

• Option types
  • .OrNull(): converts any option type to an equivalent nullable type
  • .IsTrue(): checks whether a bool option type (which might be true, false, or None) is true
  • .IsFalse(): checks whether a bool option type (which might be true, false, or None) is false
  • .OrEmpty(): returns the items in the list, or an empty list if the field is None
• Asynchronous types
  • .StartAsTask(TaskCreationOptions options = null, CancellationToken? token = null): executes a "cool" F# asynchronous workflow by creating a "hot" .NET task that can be awaited

Deleted deviations and status updates

Deviation and DeviantArtStatus objects can represent a deviation or status update that has been deleted; this is why most of the fields on those two types are marked optional. Check the is_deleted field (or IsDeleted property) before attempting to access any of the other fields.

Known issues

• Mature content filtering is not supported (use the is_mature flag on the deviation instead).
• The profile_pic field in the user.profile expansion is not supported due to circular type definitions. Get it from the full profile object instead.
• The following fields in the deviation object are not supported:
  • challenge
  • challenge_entry
  • motion_book
  • premium_folder_data
  • text_content
  • suggested_reasons
• The api_session return object is not supported.

Examples

• ExampleConsoleApp: An F# console application that shows some data on the current user's recent (and not-so-recent) submissions, along with some of their Sta.sh info. Reads the access token interactively from standard input.
• GalleryViewer: A VB.NET app that lets you see the "All" view of someone's gallery and read the descriptions of individual submissions. Uses the Client Credentials grant and stores tokens in a file.
• WebApp: An ASP.NET Core app written in C# that lets you view someone's gallery folders and corresponding submission thumbnails. Uses the Client Credentials grant and stores tokens in a database.

Authentication

See also: https://www.deviantart.com/developers/authentication

Both Authorization Code (recommended) and Implicit grant types are supported. The DeviantArtAuth module provides methods to support the Authorization Code grant type (getting tokens from an authorization code and refreshing tokens).

If you are writing a Windows desktop application, the package DeviantArtFs.WinForms package uses Internet Explorer to provide a way to get a code or token from the user using either grant type.

If you need to store the access token somewhere (such as in a database or file), you may want to create your own class that implements the IDeviantArtAccessToken, IDeviantArtRefreshToken, or IDeviantArtAutomaticRefreshToken interface. Using the latter will allow DeviantArtFs to automatically refresh the token and store the new value when it recieves an HTTP 401 response. (An InvalidRefreshTokenException is thrown if the token cannot be refreshed.)