Sylin.Koan.Data.Connector.Mongo

Sylin.Koan.Data.Connector.Mongo

MongoDB persistence for Koan Entities. Reference the package, keep the application's normal AddKoan() bootstrap, and use Entity verbs; the connector owns driver setup, discovery, naming, schema/index ensure, source routing, and readiness participation.

• Target framework: net10.0
• License: Apache-2.0

Install

The generated product surface owns support maturity. MongoDB's transitive Zen Garden contract dependency is module-free and activates nothing; applications still reference only this connector for MongoDB.

dotnet add package Sylin.Koan.Data.Connector.Mongo

Meaningful result

With MongoDB reachable, no provider registration or repository scaffold is required:

builder.Services.AddKoan();

public sealed class Book : Entity<Book>
{
    public string Title { get; set; } = "";
    public bool Published { get; set; }
}

var saved = await new Book { Title = "Meaningful steps", Published = true }.Save();
var published = await Book.Query(book => book.Published);

When Mongo is the only server-backed Data connector, it wins automatic provider election over the local JSON floor. Pin business-critical placement with [DataAdapter("mongo")] or the Default-source adapter setting when adding another connector must not move existing data.

Configuration

auto is the default and uses Koan's health-checked discovery pipeline, then the local MongoDB fallback. Use exact provider configuration only when placement must be explicit:

{
  "ConnectionStrings": {
    "Mongo": "mongodb://localhost:27017"
  },
  "Koan": {
    "Data": {
      "Mongo": {
        "Database": "Books"
      }
    }
  }
}

Named sources use Koan:Data:Sources:{name}:{Adapter,ConnectionString} plus the provider-specific mongo settings beneath that source. Credentials belong in the platform's secret store.

Capabilities

• LINQ/filter translation to native MongoDB filters for the supported expression floor
• bulk upsert/delete, atomic batches, conditional replace, TTL indexes, and fast remove
• Row-, container-, and database-scoped Data isolation composition
• provider-bounded Entity streams through DataCaps.Query.ProviderBoundedPaging
• source-aware client pooling and selection-aware readiness

Book.All() requests the complete visible set. Mongo does not invent pagination defaults or caps; use Book.Page(page, size) or Book.AllStream(batchSize: ...) when the set can grow.

Streaming boundary

AllStream and QueryStream request one numbered MongoDB page at a time. batchSize caps the Koan-visible candidate page; it does not claim a bound for opaque MongoDB driver buffers. Streaming accepts only DATA-0107's proved user-sort floor. Unsupported sorts reject before provider I/O.

These streams use offset pages. They do not provide snapshot consistency, mutation-safe traversal, resumability, or a public cursor; concurrent writes can cause skips or duplicates.

Operations boundary

A referenced but unelected Mongo connector is available, not a readiness dependency. It becomes critical when it wins default election or a runtime Entity/source operation selects it. Startup, health, and facts report the selected/participating sources with credentials redacted.

References

• Technical reference
• DATA-0107 — provider-bounded Entity streams
• Entity access and streaming