Is it?

A generic logic/rule testing engine written in Go.

IsIt is a library for contructing rules via JSON or programmatically and then testing those rules against a set of values. This code is in an alpha state right now. The API is still in flux.

Installation

go get github.com/braindev/isit

Docs

See: https://godoc.org/github.com/braindev/isit

Simple Example

rg := isit.RuleGroup{
  Logic: "or",
  Rules: []isit.Rule{
    { Property: "age", Operator: "gt_eq", Value: 18 },
    { Property: "parent_permission": Operator: "eq", Value: true },
  }
}

result, _ := rg.Test(map[string]interface{}{"age": 17, "parent_permission": false})
// result == false

result, _ := rg.Test(map[string]interface{}{"age": 17, "parent_permission": true})
// result == true

result, _ := rg.Test(map[string]interface{}{"age": 18, "parent_permission": true})
// result == true

Rule Operators

These are the types of values that should be used with together. The "Rule Value Type" is the type for the field Value on the struct Rule. The "Property Type" is the type of the value for the property. Using mismatched types will cause errors.

Rule Value Type	Operator	Property Type
numeric	gt — greater than	numeric
numeric	gt_eq — greater than or equal to	numeric
numeric	lt — less than	numeric
numeric	lt_eq — less than or equal to	numeric
numeric	eq — equal to	numeric
numeric	not_eq — not equal to	numeric
string	eq — equal to	string
string	not_eq — not equal to	string
string	regex — matches regular expression	string — the regular expression
string	not_regex — doesn't match regular expression	string — the regular expression
string	in — one of a group	[]string
string	not_in — not one of a group	[]string
bool	eq — equal to	bool
bool	not_eq — not equal to	bool
[]string	has — includes item	string
[]string	does_not_have — doesn't include item	string

Nested Example

Rule logic can be as complex as needed. Suppose the following logic needed to be tested:

if activity == "rock climbing" and (height <= 5 or weight > 280)

It could be written as:

rg := isit.RuleGroup{
  Logic: "and",
  Rules: []isit.Rule{
    { Property: "activity", Operator: "eq", Value: "rock climbing" },
    {
      RuleGroup: &isit.RuleGroup{
      Logic: "or",
      Rules: []isit.Rule{
        { Property: "height", Operator: "lt_eq", Value: 5 },
        { Property: "weight": Operator: "gt", Value: 280 },
      },
    },
  }
}

TODO

• More tests
• Add in and not_in for testing inclusion or exclusion of a string to a group of strings
• Benchmarks