Added Rule Validation Support (#2)

* Rule Validation is supported.

* Update README.md

* Rule Validation is supported.

* Rule Validation is supported.

* Rule Validation is supported.

* Rule Validation is supported.

* Rule Validation is supported.

* rule validation support for v0.1.2

* reverted changes for imports.

* reverted changes for imports.

* reverted changes for imports.

* reverted changes for imports.

Co-authored-by: shankarparimi <shankar.parimi>

Author: ShankarParimi

README.md

@@ -8,6 +8,8 @@ Golang implementation of JsonLogic (jsonlogic.com), which is an abstract syntax
 
 Custom operators are supported.
 
+Rules Validation is supported.
+
 ## Example
 
 ```golang

default.go

@@ -15,3 +15,7 @@ func Apply(rule interface{}, data interface{}) (interface{}, error) {
 func AddOperation(symbol string, op Operator) error {
 	return defaultJL.AddOperation(symbol, op)
 }
+
+func Validate(rule interface{}) error {
+	return defaultJL.Validate(rule)
+}

interface.go

@@ -4,6 +4,7 @@ package jsonlogic
 type LogicApplier interface {
 	Apply(rule interface{}, data interface{}) (interface{}, error)
 	AddOperation(symbol string, op Operator) error
+	Validate(rule interface{}) error
 }
 
 // RuleType is the type of rule

jsonlogic.go

@@ -21,6 +21,10 @@ func (jl *jsonLogic) AddOperation(symbol string, op Operator) error {
 	return nil
 }
 
+func (jl *jsonLogic) Validate(rule interface{}) error {
+	return jl.validate(rule)
+}
+
 func (jl *jsonLogic) mustAddOperation(symbol string, op Operator) {
 	if err := jl.AddOperation(symbol, op); err != nil {
 		log.Fatal(err)

validator.go

@@ -0,0 +1,32 @@
+package jsonlogic
+
+import (
+	"fmt"
+)
+
+//TODO: Call operator Specific Validate Methods.
+func (jl *jsonLogic) validate(rule RuleType) error {
+	switch rule := rule.(type) {
+	case nil, bool, float64, string:
+		return nil
+	case map[string]interface{}:
+		for opName, params := range rule {
+			_, ok := jl.ops[opName]
+			if !ok {
+				return fmt.Errorf("invalid operator: " + opName)
+			}
+			if err := jl.validate(params); err != nil {
+				return err
+			}
+		}
+	case []interface{}:
+		for _, param := range rule {
+			if err := jl.validate(param); err != nil {
+				return err
+			}
+		}
+
+	}
+
+	return nil
+}

validator_test.go

@@ -0,0 +1,101 @@
+package jsonlogic_test
+
+import (
+	"encoding/json"
+	"fmt"
+	"github.com/HuanTeng/go-jsonlogic"
+	"reflect"
+	"testing"
+)
+
+var cases = []TestCase{
+	{
+		name: "valid Rule:0",
+		rule: `{
+        ">": [
+          {
+            "var": "variable1.value"
+          }]
+		}`,
+		expect: nil,
+	},
+	{
+		name: "invalid Rule",
+		rule: `{
+        ">": [
+          {
+            "variable": "variable1.value"
+          }]
+		}`,
+		expect: fmt.Errorf("invalid operator: variable"),
+	},
+	{
+		name: "Valid Rule:1",
+		rule: `{
+        "or": {
+          ">": [
+            {
+              "var": "variable1.value"
+            },
+            {
+              "var": "variable1.value"
+            }
+          ],
+          "<": [
+            [
+              {
+                "var": "variable1.value"
+              },
+              {
+                "var": "variable1.value"
+              }
+            ],
+            70
+          ]
+        }
+      }`,
+		expect: nil,
+	},
+	{
+		name: "Invalid Rule - 1",
+		rule: `{
+        "or": {
+          "equals": [
+            {
+              "var": "variable1.value"
+            },
+            {
+              "var": "variable2.value"
+            }
+          ],
+          "fuzzy_match": [
+            [
+              {
+                "var": "variable1.value"
+              },
+              {
+                "var": "variable2.value"
+              }
+            ],
+            70
+          ]
+        }
+      }`,
+		expect: fmt.Errorf("invalid operator: equals"),
+	},
+}
+
+func TestJsonLogic_Validate(t *testing.T) {
+	var rule interface{}
+	for _, c := range cases {
+		t.Run(c.name, func(t *testing.T) {
+			if err := json.Unmarshal([]byte(c.rule), &rule); err != nil {
+				t.Errorf("rule error: %s", err)
+			}
+			err := jsonlogic.Validate(rule)
+			if !reflect.DeepEqual(err, c.expect) {
+				t.Errorf("Case %s: expect error %+v got %+v", c.name, c.expect, err)
+			}
+		})
+	}
+}