RulesEngineService

https://microsoft.github.io/RulesEngine

Run

Command Line

Prerequisites

• .NET SDK

Steps

1. Open directory source\RulesEngineService in command line and execute dotnet run.
2. Open https://localhost:5000.

Visual Studio Code

Prerequisites

• .NET SDK
• Visual Studio Code
• C# Extension

Steps

1. Open source directory in Visual Studio Code.
2. Press F5.

Visual Studio

Prerequisites

• Visual Studio

Steps

1. Open source\RulesEngineService.sln in Visual Studio.
2. Set RulesEngineService as startup project.
3. Press F5.

Example

Rules

[
    {
        "WorkflowName": "DiscountPercentage",
        "GlobalParams": [
            {
                "Name": "CompareValue",
                "Expression": "1000"
            }
        ],
        "Rules": [
            {
                "RuleName": "CreditCard",
                "Expression": "PaymentType == \"CreditCard\"",
                "SuccessEvent": "5"
            },
            {
                "RuleName": "DebitCard",
                "Expression": "PaymentType == \"DebitCard\"",
                "SuccessEvent": "10"
            },
            {
                "RuleName": "CashLessThan",
                "Expression": "PaymentType == \"Cash\" && Value < CompareValue",
                "SuccessEvent": "15"
            },
            {
                "RuleName": "CashGreaterThanOrEqual",
                "Expression": "PaymentType == \"Cash\" && Value >= CompareValue",
                "SuccessEvent": "20"
            }
        ]
    }
]

Execute

var json = System.IO.File.ReadAllText("Rules.json");

var workflows = JsonSerializer.Deserialize<Workflow[]>(json);

var rulesEngine = new RulesEngine.RulesEngine(workflows);

var parameters = new RuleParameter[]
{
    new RuleParameter("PaymentType", "Cash"),
    new RuleParameter("Value", 1000)
};

var result = await rulesEngine.ExecuteAllRulesAsync(workflows.First().WorkflowName, parameters);

Result

[
    {
        "rule": {
            "ruleName": "CreditCard",
            "expression": "PaymentType == \"CreditCard\"",
            "successEvent": "5"
        },
        "isSuccess": false,
        "inputs": {
            "PaymentType": "Cash",
            "Value": 1000,
            "CompareValue": 1000
        }
    },
    {
        "rule": {
            "ruleName": "DebitCard",
            "expression": "PaymentType == \"DebitCard\"",
            "successEvent": "10"
        },
        "isSuccess": false,
        "inputs": {
            "PaymentType": "Cash",
            "Value": 1000,
            "CompareValue": 1000
        }
    },
    {
        "rule": {
            "ruleName": "CashLessThan",
            "expression": "PaymentType == \"Cash\" && Value < CompareValue",
            "successEvent": "15"
        },
        "isSuccess": false,
        "inputs": {
            "PaymentType": "Cash",
            "Value": 1000,
            "CompareValue": 1000
        }
    },
    {
        "rule": {
            "ruleName": "CashGreaterThanOrEqual",
            "expression": "PaymentType == \"Cash\" && Value >= CompareValue",
            "successEvent": "20"
        },
        "isSuccess": true,
        "inputs": {
            "PaymentType": "Cash",
            "Value": 1000,
            "CompareValue": 1000
        }
    }
]

Value

var value = result.SingleOrDefault(rule => rule.IsSuccess)?.Rule.SuccessEvent; // 20