di-rule

di-rule

A Go Rules Engine

Work in Progress, NOT Ready to be used yet

Project from a Golang learner. Please give feedbacks.

Create Rules based on Conditions (Condition) which can be Logical Conditions (LogicalCondition) or Value Comparator Conditions (ComparatorCondition)

Value Comparator Conditions are Value comparators with Path string path to json element Operator string Value string¡bool¡numeric

Input json entity

Get di-rule

Get dependencies

go get -u github.com/tidwall/gjson
go get -u github.com/jcantonio/couchdb-golang

Get di-rule

go get -u github.com/jcantonio/di-rule

REST API

Requires CouchDB
http://couchdb.apache.org/

Start server

Create a file config.yml

db:
    name:     di-rule
    Address:  "http://localhost"
    port:     5984
server:
    port:     8000

Start server.

overview

Di-Rule saves and keeps in memory rules created via its REST API. Each Rule is composed of

• name: name of the rule
• description: description of the rule
• entity: entity related to the rule
• condition: condition of application of the rule
• actions: actions to be executed is condition is met

Once the rules are loaded, use the run end-point to pass an entity and get all actions to be executed for it.

Create Rule

POST http://localhost:8000/rules

{
    "name": "R3",
    "entity": "CUSTOMER",
    "description": "R3 checks if the shipment is to go to the US or FR",
    	"actions": [{
		"name": "DoThat"
	}],
    "condition": {
        "op": "or",
        "conditions": [
            {
                "path": "shipTo.countryCode",
                "op": "=",
                "value": "FR"
            },
            {
                "path": "shipTo.countryCode",
                "op": "=",
                "value": "US"
            }
        ]
    }
}

response

{"data":{"_id":%ruleID%,"_rev":%revision%},"status":"success"}

for example

{"data":{"_id":"2f8198bb-7b02-4c08-9c9f-9ba02680a416","_rev":"1-c7809e5a70f4b1fb313b21df966f1eff"},"status":"success"}

Update Rule

PUT http://localhost:8000/rules/%ruleID%

{
  	"_id": %ruleID%,
  	"_rev": %rev%,
    "name": "R3",
    "entity": "CUSTOMER",
    "description": "R3 checks if the shipment is to go to the US or FR",
    	"actions": [{
		"name": "DoThatUpdate"
	}],
    "condition": {
        "op": "or",
        "conditions": [
            {
                "path": "shipTo.countryCode",
                "op": "=",
                "value": "FR"
            },
            {
                "path": "shipTo.countryCode",
                "op": "=",
                "value": "US"
            }
        ]
    }
}

Delete Rule

DELETE http://localhost:8000/rules/%ruleID%

Run Rules

POST http://localhost:8000/processes/run?entity=%ENTITY% e.g. POST http://localhost:8000/processes/run?entity=CUSTOMER

{ "name"   : "John Smith",
	"sku"    : "20223",
	"price"  : 23.95,
	"shipTo" : { "name" : "Jane Smith",
				 "address" : "123 Maple Street",
				 "city" : "Pretendville",
				 "state" : "NY",
				 "zip"   : "12345",
				 "countryCode"   : "FR" },
	"billTo" : { "name" : "John Smith",
				 "address" : "123 Maple Street",
				 "city" : "Pretendville",
				 "state" : "NY",
				 "zip"   : "12345",
				 "countryCode"   : "FR" }
  }

Get Rule

GET http://localhost:8000/rules/%ruleID%

Get Rules

GET http://localhost:8000/rules??size=10&page=1

Golang API

To fill

Roadmap

• string comparator: equal - DONE
• logical comparators: And - DONE
• logical comparators: Or - DONE
• string comparator: equal - DONE
• string comparator: regex - DONE
• number comparator: equal - DONE
• number comparator: greater - DONE
• number comparator: less - DONE
• nil comparator
• date comparator: equal
• date comparator: greater
• date comparator: less
• compare when changes
• REST : Add Rule in CouchDB - DONE
• REST : Execute Rule - DONE