RuleEngine

With RuleEngine you can write rules, which consist of an expression and a patch definition, to modify a object/model.

These rules can be defined in yaml or with typed C# objects.

Release Notes

Please see the changelog!

Example

Provided the following input object

Name: Henk Age: 15 Phone: 0612345678 Address: StreetName: Hoofdstraat StreetNumber: 25a City: Amsterdam PostalCode: 1234AA WorkAddress: null # Same type/fields as Address

Replacing a single property

rules: - condition: Age < 16 patch: Age: 25

The condition Age < 16 evaluates to: true
Thus the Age property becomes: 25

Replacing multiple properties at once (merge)

rules: - condition: Phone.StartsWith("06") patch: Phone: 0612341234 Address: City: Hilversum

The condition Phone.StartsWith("06") evaluates to: true
Thus the Phone property becomes 0621341234 and Address.City becomes Hilversum

Using lambda expressions in assignments

With a Lambda expression it is possible to use logic to assign the object, take a look at the following examples.

patch: myProperty1: input => input.Name # referencing the input object myProperty2: x => $"prefix-{x.Name}-postfix" # using a custom identifier with string interpolation myYear: _ => DateTime.Now.Year # omitting the input object and using DateTime C# class

Copy-ing properties from the input object

rules: - condition: true patch: # copy to child object (not null) WorkAddress: input => input.Address

Here the condition is true
The result becomes:

Name: Henk Age: 15 Phone: 0612345678 Address: StreetName: Hoofdstraat StreetNumber: 25a City: Amsterdam PostalCode: 1234AA WorkAddress: StreetName: Hoofdstraat StreetNumber: 25a City: Amsterdam PostalCode: 1234AA

Finding the best tool for the job

Running a benchmark

dotnet run -c Release --project RuleEngine.Benchmark

Results:

• Patching objects
• Expression evaluation

Resources

All this was not possible without the following libraries:

• ExpressionEvaluator
• Newtonsoft.Json