Fluxum.Sdk 0.2.1

Fluxum C# SDK

The async/await .NET client for the Fluxum realtime database (SPEC-011, T7.6), distributed as the Fluxum.Sdk NuGet package. No third-party dependencies — the SDK carries its own minimal MessagePack codec and FluxBIN row reader.

dotnet add package Fluxum.Sdk

using Fluxum.Sdk;

await using var db = await Connection.ConnectAsync(
    "fluxum://127.0.0.1:15801",
    System.Text.Encoding.UTF8.GetBytes("my-token"),
    tables); // from `fluxum generate --lang csharp`

await db.SubscribeAsync(new[] { "SELECT * FROM ChatMessage" });
await db.CallReducerAsync("send_chat", new object?[] { 1, "hello" });
// TxUpdates land in db.Cache; read db.Cache.Rows("ChatMessage").

What you get

• Connection — one session over FluxRPC/TCP: authenticate, subscribe (each query's InitialData populates a local row cache), call reducers, and receive TxUpdate diffs on the same socket. Every operation is async and takes a CancellationToken.
• Transparent reconnect (SDK-047): on connection loss the client reconnects, re-authenticates, resubscribes every active query and reconciles its cache — the application keeps its handle across the outage.
• A per-table row cache keyed by primary key, with per-query ownership so an UnsubscribeAsync drops only the rows that query held (SDK-044).
• Idiomatic errors: a server failure is a FluxumException carrying the stable SPEC-028 Code (and Catalog name for an Error frame).

Typed bindings

Generate typed row records and reducer wrappers from a running server's schema (or a saved schema.json):

fluxum generate --lang csharp --schema http://127.0.0.1:15800 --out ./FluxumGen

This emits Tables.cs (a record row + <Table>Codec.Decode + the cache hook <Table>Codec.TableSchema() per table) and Reducers.cs (a static async Task <Reducer>(...) per client-callable reducer), namespace FluxumGen. Offline generation from a saved schema produces byte-identical output (SPEC-011 acceptance 11).

Testing

The SDK is validated by the shared conformance corpus (tests/conformance/) — the same declarative scenarios every Fluxum SDK runs against the same server build (TST-052). The runner boots a fresh fluxum-server per scenario, so build it first:

cargo build -p fluxum-server
cd sdks/csharp && dotnet test Fluxum.Sdk.Tests/Fluxum.Sdk.Tests.csproj