SocialPoster.Posting 0.6.5

SocialPoster.Posting

Post text and media to X, Bluesky, LinkedIn, Mastodon and Threads from any .NET app. No database, UI or ASP.NET required: it needs only HttpClient and a place to read your tokens from.

This is the posting engine behind SocialPoster, the desktop/Blazor app.

Install

Requires .NET 10. Add the package with the .NET CLI:

dotnet add package SocialPoster.Posting

Or with the Package Manager Console in Visual Studio:

Install-Package SocialPoster.Posting

Or add it to your .csproj directly:

<PackageReference Include="SocialPoster.Posting" Version="0.6.1" />

To build from source instead, clone the repository and add a project reference:

dotnet add reference path/to/SocialPoster/src/SocialPoster.Posting/SocialPoster.Posting.csproj

Quick start

using Microsoft.Extensions.DependencyInjection;
using SocialPoster.Posting;
using SocialPoster.Posting.Services;

var services = new ServiceCollection();
services.AddSocialPosting();
services.AddSingleton<ICredentialStore>(new InMemoryCredentialStore(new Dictionary<string, string?>
{
    [SettingKeys.BlueskyHandle]      = "you.bsky.social",
    [SettingKeys.BlueskyAppPassword] = "xxxx-xxxx-xxxx-xxxx",
    [SettingKeys.MastodonInstance]   = "https://mastodon.social/",
    [SettingKeys.MastodonAccessToken] = "...",
}));

await using var provider = services.BuildServiceProvider();
var publisher = provider.GetRequiredService<SocialPublisher>();

var results = await publisher.PublishTextAsync("Hello from .NET!", [Platform.Bluesky, Platform.Mastodon]);
foreach (var r in results)
    Console.WriteLine(r.Success ? $"{r.Platform}: {r.Url}" : $"{r.Platform} failed: {r.Error}");

Each platform is rendered, validated and published independently. A failure on one platform (bad token, post too long, unsupported media) is returned as a PublishResult with Success = false; it never throws or stops the others.

Credentials

Clients read tokens through ICredentialStore, using the keys in SettingKeys:

InMemoryCredentialStore is the default. To use your own vault, key store or config, implement ICredentialStore and register it before or after AddSocialPosting() (yours wins).

Posting with media, mentions and previews

• publisher.PublishAsync(templates, resolve, media) renders a template per platform. {@key} mentions are resolved by your ContactResolver to each platform's handle format (@user@server on Mastodon, a real facet on Bluesky, a LinkedIn URN, and so on) and fall back to a plain name when a contact has no account there.
• PostRenderer.Render(platform, template, resolve) gives you the exact text, character count and warnings without posting, which is handy for live previews.
• MediaAttachment / MediaRules check per-platform limits (counts, sizes, formats). Threads is text only: its API accepts media only by public URL, not uploads.
• Counting follows each platform's rules (X weighted characters and 23-character URLs, Bluesky graphemes with shortened links, Mastodon/Threads graphemes).

Individual clients (BlueskyClient, XClient, LinkedInClient, MastodonClient, ThreadsClient) are public if you want to call one directly.

Notes

• Everything lives in the SocialPoster.Posting and SocialPoster.Posting.Services namespaces. The SocialPoster app (SocialPoster.Core) is built on these same types.
• Tokens are sent only to the platform's own host; Mastodon and Threads clients never follow redirects.
• HttpClient timeout defaults to 30 minutes for large uploads: AddSocialPosting(o => o.PostingTimeout = ...).

MIT licensed.