DeviantArtFs 7.0.0-beta1

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 one or more parameters:

• token (an object that implements the IDeviantArtAccessToken interface and provides the library with the API credentials)
• expansion (on some requests; allows user object expansion)
• A parameter specific to the request (if any)
• A range specifier (for endpoints that ask the user to request a particular range of results
  • paging: a DeviantArtPagingParams record, which specifies an offset and an optional limit / page size
    • DeviantArtFs is aware of the maximum limits for each API request; to request the maximum page size, use DeviantArtPagingParams.MaxFrom
  • cursor: a string provided in the previous page's result (use null to start at the beginning)
  • offset / limit: used in place of paging or cursor in methods which return AsyncSeq<T>

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

All return types from API calls are wrapped in either F# asynchronous workflows (FSharpAsync<T>) or F# asynchronous sequences (using the package FSharp.Control.AsyncSeq), and the FSharpOption<T> type is used extensively in object models. To help you work with these types in C# or VB.NET, DeviantArtFs provides extension methods 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 contained by a list option type, or an empty list if the field is None
• Asynchronous types
  • .Take(int count): sets a limit on the amount of items returned by an F# asynchronous sequence
  • .ThenToArray(): converts an F# asynchronous sequence into an asynchronous workflow that collects all items in a single array
  • .ThenToList(): converts an F# asynchronous sequence into an asynchronous workflow that collects all items in a single immutable list
  • .ToAsyncEnumerable(): converts an F# asynchronous sequence into a .NET IAsyncEnumerable<T> (.NET 5.0+ only)
  • .StartAsTask(TaskCreationOptions options = null, CancellationToken? token = null): executes a "cool" F# asynchronous workflow by creating a "hot" .NET task that can be awaited

The FSharpList<T> type also appears often, but this type implements IEnumerable<T> and can be converted to a normal list or array using LINQ.

Any C# or VB.NET code that uses this library to call the DeviantArt API is expected to use either .ToAsyncEnumerable() or .StartAsTask() on each API call.

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.

Partial updates

Stash.Update and User.ProfileUpdate allow you to choose which fields to update on the object. DeviantArtFs uses discriminated unions to represent these updates:

await Requests.User.ProfileUpdate.ExecuteAsync(token, new[] {
    ProfileUpdateField.NewArtistLevel(ArtistLevel.Student),
    ProfileUpdateField.NewWebsite("https://www.example.com")
});

await Requests.Stash.Update.ExecuteAsync(token, 12345678L, new[] {
    UpdateField.NewTitle("new stack title"),
    UpdateField.ClearDescription
});

Note that DeviantArt allows a null value for the "description" field on a Sta.sh stack, and this is represented by its own union case.

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.)