flogo expressions support for rule conditions

common/model/tuple.go

@@ -23,6 +23,7 @@ type Tuple interface {
 	GetBool(name string) (val bool, err error)
 	//GetDateTime(name string) time.Time
 	GetKey() TupleKey
+	GetMap() map[string]interface{}
 }
 
 //MutableTuple mutable part of the tuple
@@ -210,7 +211,7 @@ func (t *tupleImpl) initTupleWithKeyValues(td *TupleDescriptor, values ...interf
 	t.key = tk
 	//populate the tuple key fields with the key values
 	for _, keyProp := range td.GetKeyProps() {
-		t.tuples [keyProp] = tk.GetValue(keyProp)
+		t.tuples[keyProp] = tk.GetValue(keyProp)
 	}
 	return err
 }
@@ -273,3 +274,7 @@ func (t *tupleImpl) isKeyProp(propName string) bool {
 	}
 	return found
 }
+
+func (t *tupleImpl) GetMap() map[string]interface{} {
+	return t.tuples
+}

common/model/tuplekey.go

@@ -2,8 +2,8 @@ package model
 
 import (
 	"fmt"
-	"reflect"
 	"github.com/project-flogo/core/data/coerce"
+	"reflect"
 )
 
 // TupleKey primary key of a tuple

common/model/types.go

@@ -26,16 +26,18 @@ type MutableRule interface {
 	SetAction(actionFn ActionFunction)
 	SetPriority(priority int)
 	SetContext(ctx RuleContext)
+	AddExprCondition(conditionName string, cExpr string, ctx RuleContext) error
+	AddIdrsToRule(idrs []TupleType)
 }
 
 //Condition interface to maintain/get various condition properties
 type Condition interface {
 	GetName() string
-	GetEvaluator() ConditionEvaluator
 	GetRule() Rule
 	GetIdentifiers() []TupleType
 	GetContext() RuleContext
 	String() string
+	Evaluate(string, string, map[TupleType]Tuple, RuleContext) (bool, error)
 }
 
 // RuleSession to maintain rules and assert tuples against those rules
@@ -71,7 +73,6 @@ type RuleSession interface {
 
 	//RtcTransactionHandler
 	RegisterRtcTransactionHandler(txnHandler RtcTransactionHandler, handlerCtx interface{})
-
 }
 
 //ConditionEvaluator is a function pointer for handling condition evaluations on the server side
@@ -92,16 +93,14 @@ type ValueChangeListener interface {
 
 type RtcTxn interface {
 	//map of type and map of key/tuple
-	GetRtcAdded () map[string]map[string]Tuple
+	GetRtcAdded() map[string]map[string]Tuple
 	GetRtcModified() map[string]map[string]RtcModified
 	GetRtcDeleted() map[string]map[string]Tuple
-
 }
 
 type RtcModified interface {
 	GetTuple() Tuple
 	GetModifiedProps() map[string]bool
 }
 
-type RtcTransactionHandler func (ctx context.Context, rs RuleSession, txn RtcTxn, txnContext interface{})
-
+type RtcTransactionHandler func(ctx context.Context, rs RuleSession, txn RtcTxn, txnContext interface{})

config/config.go

@@ -23,17 +23,19 @@ type RuleSessionDescriptor struct {
 
 // RuleDescriptor defines a rule
 type RuleDescriptor struct {
-	Name       string
-	Conditions []*ConditionDescriptor
-	ActionFunc model.ActionFunction
-	Priority   int
+	Name        string
+	Conditions  []*ConditionDescriptor
+	ActionFunc  model.ActionFunction
+	Priority    int
+	Identifiers []string
 }
 
 // ConditionDescriptor defines a condition in a rule
 type ConditionDescriptor struct {
 	Name        string
 	Identifiers []string
 	Evaluator   model.ConditionEvaluator
+	Expression  string
 }
 
 func (c *RuleDescriptor) UnmarshalJSON(d []byte) error {
@@ -42,6 +44,7 @@ func (c *RuleDescriptor) UnmarshalJSON(d []byte) error {
 		Conditions   []*ConditionDescriptor `json:"conditions"`
 		ActionFuncId string                 `json:"actionFunction"`
 		Priority     int                    `json:"priority"`
+		Identifiers  []string               `json:"identifiers"`
 	}{}
 
 	if err := json.Unmarshal(d, ser); err != nil {
@@ -52,13 +55,22 @@ func (c *RuleDescriptor) UnmarshalJSON(d []byte) error {
 	c.Conditions = ser.Conditions
 	c.ActionFunc = GetActionFunction(ser.ActionFuncId)
 	c.Priority = ser.Priority
+	c.Identifiers = ser.Identifiers
 
 	return nil
 }
 
 func (c *RuleDescriptor) MarshalJSON() ([]byte, error) {
 	buffer := bytes.NewBufferString("{")
 	buffer.WriteString("\"name\":" + "\"" + c.Name + "\",")
+	if c.Identifiers != nil {
+		buffer.WriteString("\"identifiers\":[")
+		for _, id := range c.Identifiers {
+			buffer.WriteString("\"" + id + "\",")
+		}
+		buffer.Truncate(buffer.Len() - 1)
+		buffer.WriteString("],")
+	}
 
 	buffer.WriteString("\"conditions\":[")
 	for _, condition := range c.Conditions {
@@ -82,6 +94,7 @@ func (c *ConditionDescriptor) UnmarshalJSON(d []byte) error {
 		Name        string   `json:"name"`
 		Identifiers []string `json:"identifiers"`
 		EvaluatorId string   `json:"evaluator"`
+		Expression  string   `json:"expression"`
 	}{}
 
 	if err := json.Unmarshal(d, ser); err != nil {
@@ -91,22 +104,26 @@ func (c *ConditionDescriptor) UnmarshalJSON(d []byte) error {
 	c.Name = ser.Name
 	c.Identifiers = ser.Identifiers
 	c.Evaluator = GetConditionEvaluator(ser.EvaluatorId)
+	c.Expression = ser.Expression
 
 	return nil
 }
 
 func (c *ConditionDescriptor) MarshalJSON() ([]byte, error) {
 	buffer := bytes.NewBufferString("{")
 	buffer.WriteString("\"name\":" + "\"" + c.Name + "\",")
-	buffer.WriteString("\"identifiers\":[")
-	for _, id := range c.Identifiers {
-		buffer.WriteString("\"" + id + "\",")
+	if c.Identifiers != nil {
+		buffer.WriteString("\"identifiers\":[")
+		for _, id := range c.Identifiers {
+			buffer.WriteString("\"" + id + "\",")
+		}
+		buffer.Truncate(buffer.Len() - 1)
+		buffer.WriteString("],")
 	}
-	buffer.Truncate(buffer.Len() - 1)
-	buffer.WriteString("],")
 
 	conditionEvaluatorID := GetConditionEvaluatorID(c.Evaluator)
-	buffer.WriteString("\"evaluator\":\"" + conditionEvaluatorID + "\"}")
+	buffer.WriteString("\"evaluator\":\"" + conditionEvaluatorID + "\",")
+	buffer.WriteString("\"expression\":\"" + c.Expression + "\"}")
 
 	return buffer.Bytes(), nil
 }

config/manager.go

@@ -57,26 +57,3 @@ func (m *ResourceManager) GetRuleActionDescriptor(uri string) (*RuleActionDescri
 
 	return nil, errors.New("cannot find RuleSession: " + uri)
 }
-
-//ioMetadata support
-/*
-type ActionResource struct {
-	IOMetadata *metadata.IOMetadata `json:"metadata"`
-}
-
-type ResManager struct {
-	IOMetadata *metadata.IOMetadata
-}
-
-func (m *ResManager) LoadResource(resConfig *resource.Config) (*resource.Resource, error) {
-
-	var res *ActionResource
-	err := json.Unmarshal(resConfig.Data, &res)
-	if err != nil {
-		return nil, fmt.Errorf("error unmarshalling metadata resource with id '%s', %s", resConfig.ID, err.Error())
-	}
-
-	m.IOMetadata = res.IOMetadata
-	return resource.New("ruleaction", m.IOMetadata), nil
-}
-*/

examples/flogo/simple/flogo.json

@@ -4,6 +4,13 @@
   "version": "0.0.1",
   "description": "Sample Flogo App",
   "appModel": "1.0.0",
+  "properties": [
+    {
+      "name": "name",
+      "type": "string",
+      "value": "testprop"
+    }
+  ],
   "triggers": [
     {
       "id": "receive_http_message",
@@ -12,32 +19,17 @@
         "port": "7777"
       },
       "handlers": [
-        {   
-          "settings": {
-            "method": "GET",
-            "path": "/test/n1"
-          },
-          "actions": [
-            {
-              "id": "simple_rule",
-              "input": {
-                "tupletype": "n1",
-							  "values": "=$.queryParams"
-              }
-            }
-          ]
-        },
         {
           "settings": {
             "method": "GET",
-            "path": "/test/n2"
+            "path": "/test/:tupleType"
           },
           "actions": [
             {
               "id": "simple_rule",
               "input": {
-                "tupletype": "n2",
-							  "values": "=$.queryParams"
+                "tupletype": "=$.pathParams.tupleType",
+                "values": "=$.queryParams"
               }
             }
           ]
@@ -92,22 +84,18 @@
             }
           ],
           "output": [
-             {
-               "name": "outputData",
-               "type": "any"
-             }
+            {
+              "name": "outputData",
+              "type": "any"
+            }
           ]
         },
         "rules": [
           {
             "name": "n1.name == Bob",
             "conditions": [
               {
-                "name": "c1",
-                "identifiers": [
-                  "n1"
-                ],
-                "evaluator": "checkForBob"
+                "expression" : "$.n1.name == 'Bob'"
               }
             ],
             "actionFunction": "checkForBobAction"
@@ -116,22 +104,37 @@
             "name": "n1.name == Bob \u0026\u0026 n1.name == n2.name",
             "conditions": [
               {
-                "name": "c1",
                 "identifiers": [
                   "n1"
                 ],
                 "evaluator": "checkForBob"
               },
               {
-                "name": "c2",
-                "identifiers": [
-                  "n1",
-                  "n2"
-                ],
-                "evaluator": "checkSameNamesCondition"
+                "expression" : "($.n1.name == 'Bob') \u0026\u0026 ($.n1.name == $.n2.name)"
               }
             ],
             "actionFunction": "checkSameNamesAction"
+          },
+          {
+            "name": "env variable example",
+            "conditions": [
+              {
+                "expression" : "($.n1.name == $env['name'])"
+              }
+            ],
+            "actionFunction": "envVarExampleAction"
+          },
+          {
+            "name": "flogo property example",
+            "identifiers": [
+              "n1"
+            ],
+            "conditions": [
+              {
+                "expression" : "('testprop' == $property['name'])"
+              }
+            ],
+            "actionFunction": "propertyExampleAction"
           }
         ]
       }

examples/flogo/simple/functions.go

@@ -12,6 +12,8 @@ import (
 func init() {
 	config.RegisterActionFunction("checkForBobAction", checkForBobAction)
 	config.RegisterActionFunction("checkSameNamesAction", checkSameNamesAction)
+	config.RegisterActionFunction("envVarExampleAction", envVarExampleAction)
+	config.RegisterActionFunction("propertyExampleAction", propertyExampleAction)
 
 	config.RegisterConditionEvaluator("checkForBob", checkForBob)
 	config.RegisterConditionEvaluator("checkSameNamesCondition", checkSameNamesCondition)
@@ -72,3 +74,26 @@ func StartupRSFunction(ctx context.Context, rs model.RuleSession, startupCtx map
 	rs.Assert(nil, t3)
 	return nil
 }
+
+func envVarExampleAction(ctx context.Context, rs model.RuleSession, ruleName string, tuples map[model.TupleType]model.Tuple, ruleCtx model.RuleContext) {
+	fmt.Printf("Rule fired: [%s]\n", ruleName)
+	t1 := tuples["n1"]
+	if t1 == nil {
+		fmt.Println("Should not get nil tuples here in JoinCondition! This is an error")
+		return
+	} else {
+		nm, _ := t1.GetString("name")
+		fmt.Printf("n1.name is [%s]\n", nm)
+	}
+}
+func propertyExampleAction(ctx context.Context, rs model.RuleSession, ruleName string, tuples map[model.TupleType]model.Tuple, ruleCtx model.RuleContext) {
+	fmt.Printf("Rule fired: [%s]\n", ruleName)
+	t1 := tuples["n1"]
+	if t1 == nil {
+		fmt.Println("Should not get nil tuples here ! This is an error")
+		return
+	} else {
+		nm, _ := t1.GetString("name")
+		fmt.Printf("n1.name is [%s]\n", nm)
+	}
+}

go.mod

@@ -4,5 +4,5 @@ require (
 	github.com/aws/aws-sdk-go v1.18.3
 	github.com/gorilla/websocket v1.4.0
 	github.com/oklog/ulid v1.3.1
-	github.com/project-flogo/core v0.9.0-alpha.6
+	github.com/project-flogo/core v0.9.2
 )

rete/filternode.go

@@ -94,9 +94,13 @@ func (fn *filterNodeImpl) assertObjects(ctx context.Context, handles []reteHandl
 		}
 		tupleMap := convertToTupleMap(tuples)
 		cv := fn.conditionVar
-		toPropagate := cv.GetEvaluator()(cv.GetName(), cv.GetRule().GetName(), tupleMap, cv.GetContext())
-		if toPropagate {
-			fn.nodeLinkVar.propagateObjects(ctx, handles)
+		toPropagate, err := cv.Evaluate(cv.GetName(), cv.GetRule().GetName(), tupleMap, cv.GetContext())
+		if err == nil {
+			if toPropagate {
+				fn.nodeLinkVar.propagateObjects(ctx, handles)
+			}
+		} else {
+			//todo
 		}
 	}
 }