Muonroi.RuleEngine.DecisionTable 1.0.0-alpha.16

Muonroi.RuleEngine.DecisionTable

DMN-style decision table engine with FEEL expressions, multi-backend persistence, structural validation, and import/export for the Muonroi Rule Engine.

Decision tables let you encode business rules as a matrix of input conditions and output values — no code changes needed to update rule logic at runtime. This package provides the models, FEEL expression evaluator, validators, converters, serializers, and a pluggable store (in-memory, SQL Server, or PostgreSQL) that power the Muonroi decision table subsystem. The optional companion package Muonroi.RuleEngine.DecisionTable.Web exposes REST endpoints and a live-edit UI on top of this core engine.

Installation

dotnet add package Muonroi.RuleEngine.DecisionTable --prerelease

Quick Start

Register the engine in Program.cs. No connection string = in-memory store (ideal for testing and small deployments):

builder.Services.AddDecisionTableEngine();

Persist tables to PostgreSQL:

builder.Services.AddDecisionTableEngine(options =>
{
    options.PostgresConnectionString =
        builder.Configuration.GetConnectionString("RuleDb");
});

Execute a table once retrieved from the store:

using Muonroi.RuleEngine.DecisionTable;
using Muonroi.RuleEngine.DecisionTable.Models;
using Muonroi.RuleEngine.DecisionTable.Stores;

// IDecisionTableStore and IDecisionTableExecutor are injected via DI.
DecisionTable? table = await store.GetByIdAsync("loan-approval");

DecisionTableExecutionResult result = await executor.ExecuteAsync(
    table!,
    new Dictionary<string, object?>
    {
        ["age"]    = 35,
        ["income"] = 75_000m,
        ["score"]  = 720
    });

foreach (DecisionTableOutputRow row in result.MatchedRows)
{
    Console.WriteLine(row.Outputs["decision"]);   // e.g. "Approved"
}

See the full working example in Quickstart.DecisionTable.

Features

• FEEL expression evaluation — full FEEL cell evaluator (FullFeelCellEvaluator) with a lightweight fallback (SimplifiedFeelCellEvaluator); numeric, string, range, and boolean expressions supported.
• Nine hit policies — First, Unique, Collect, Priority, OutputOrder, CollectSum, CollectMin, CollectMax, CollectCount.
• Multi-backend persistence — in-memory (default), SQL Server, or PostgreSQL via EF Core; automatic schema migration on startup.
• Audit trail and versioning — every SaveAsync records an audit entry and increments a version snapshot; full history queryable through IDecisionTableStore.
• Structural validation — DecisionTableValidator checks expression syntax, overlap, gaps, and multi-column redundancy before rules are persisted or executed.
• Excel import — ExcelToDecisionTableConverter reads Excel files with in: / out: column headers directly into a DecisionTable model.
• DMN 1.3 import/export — DmnExporter.ExportToDmnXml and DmnImporter.ImportFromDmnXml provide bidirectional spec-compliant DMN 1.3 XML exchange.
• JSON and XML serializers — DecisionTableJsonSerializer and DecisionTableXmlSerializer for custom serialization needs.
• Rule conversion — DecisionTableToRuleConverter bridges a decision table into the Muonroi Rule Engine's IRule pipeline.
• Structural diffing — DecisionTableDiffer produces a DecisionTableDiff (row adds/removes, cell changes, column schema changes) between two table versions.
• Bulk operations — IDecisionTableStore.BulkUpsertAsync and BulkDeleteAsync for batch management.

Configuration

DI registration

builder.Services.AddDecisionTableEngine(options =>
{
    // SQL Server persistence (optional)
    options.SqlServerConnectionString = "Server=...";

    // PostgreSQL persistence (optional, takes priority over SqlServer if both are set)
    options.PostgresConnectionString = "Host=...";

    // Database schema (default: "dbo")
    options.Schema = "rules";

    // Automatically create/migrate the schema on startup (default: true)
    options.AutoMigrateDatabase = true;
});

DecisionTableEngineOptions

When neither connection string is set, InMemoryDecisionTableStore is registered.

API Reference

Samples

• Quickstart.DecisionTable — minimal ASP.NET Core API wiring AddDecisionTableEngine with a PostgreSQL backend and Swagger UI

Compatibility

• Target framework: net8.0
• License: Apache-2.0 (OSS)

Related Packages

• Muonroi.RuleEngine.Abstractions — shared contracts (IRule, FactBag, RuleResult) that this package builds on
• Muonroi.RuleEngine.DecisionTable.Web — REST controllers and live-edit UI layer over this engine
• Muonroi.RuleEngine.Core — rule orchestrator that can consume decision tables via DecisionTableToRuleConverter
• Muonroi.Data.EntityFrameworkCore — EF Core base infrastructure used by the persistent store

License

Apache-2.0. See LICENSE-APACHE.