Empty fields Marshaled as "field":null (#172)

fixes #171

Signed-off-by: Spolti <filippespolti@gmail.com>

Author: spolti

model/states.go

@@ -104,7 +104,7 @@ type BaseState struct {
 func (b *BaseState) MarshalJSON() ([]byte, error) {
 	type Alias BaseState
 	if b == nil {
-		return []byte("null"), nil
+		return nil, nil
 	}
 	cus, err := json.Marshal(struct {
 		*Alias
@@ -148,7 +148,7 @@ type State struct {
 
 func (s *State) MarshalJSON() ([]byte, error) {
 	if s == nil {
-		return []byte("null"), nil
+		return nil, nil
 	}
 	r := []byte("")
 	var errs error

model/switch_state.go

@@ -16,6 +16,7 @@ package model
 
 import (
 	"encoding/json"
+	"strings"
 )
 
 // SwitchState is workflow's gateways: direct transitions onf a workflow based on certain conditions.
@@ -36,6 +37,23 @@ type SwitchState struct {
 	Timeouts *SwitchStateTimeout `json:"timeouts,omitempty"`
 }
 
+func (s *SwitchState) MarshalJSON() ([]byte, error) {
+	type Alias SwitchState
+	custom, err := json.Marshal(&struct {
+		*Alias
+		Timeouts *SwitchStateTimeout `json:"timeouts,omitempty"`
+	}{
+		Alias:    (*Alias)(s),
+		Timeouts: s.Timeouts,
+	})
+
+	// Avoid marshal empty objects as null.
+	st := strings.Replace(string(custom), "\"eventConditions\":null,", "", 1)
+	st = strings.Replace(st, "\"dataConditions\":null,", "", 1)
+	st = strings.Replace(st, "\"end\":null,", "", -1)
+	return []byte(st), err
+}
+
 // DefaultCondition Can be either a transition or end definition
 type DefaultCondition struct {
 	// Serverless workflow states can have one or more incoming and outgoing transitions (from/to other states).
@@ -68,18 +86,6 @@ func (e *DefaultCondition) UnmarshalJSON(data []byte) error {
 	return err
 }
 
-func (s *SwitchState) MarshalJSON() ([]byte, error) {
-	type Alias SwitchState
-	custom, err := json.Marshal(&struct {
-		*Alias
-		Timeouts *SwitchStateTimeout `json:"timeouts,omitempty"`
-	}{
-		Alias:    (*Alias)(s),
-		Timeouts: s.Timeouts,
-	})
-	return custom, err
-}
-
 // SwitchStateTimeout defines the specific timeout settings for switch state
 type SwitchStateTimeout struct {
 	// Default workflow state execution timeout (ISO 8601 duration format)

model/util.go

@@ -31,8 +31,8 @@ import (
 	"sigs.k8s.io/yaml"
 )
 
+// Kind ...
 // +k8s:deepcopy-gen=false
-
 type Kind interface {
 	KindValues() []string
 	String() string
@@ -41,6 +41,8 @@ type Kind interface {
 // TODO: Remove global variable
 var httpClient = http.Client{Timeout: time.Duration(1) * time.Second}
 
+// UnmarshalError ...
+// +k8s:deepcopy-gen=false
 type UnmarshalError struct {
 	err           error
 	parameterName string

model/zz_generated.deepcopy.go

@@ -956,10 +956,10 @@ states:
 		assert.True(t, strings.Contains(string(b), "{\"name\":\"ParallelExec\",\"type\":\"parallel\",\"transition\":{\"nextState\":\"CheckVisaStatusSwitchEventBased\"},\"branches\":[{\"name\":\"ShortDelayBranch\",\"actions\":[{\"subFlowRef\":{\"workflowId\":\"shortdelayworkflowid\",\"invoke\":\"sync\",\"onParentComplete\":\"terminate\"},\"actionDataFilter\":{\"useResults\":true}}],\"timeouts\":{\"actionExecTimeout\":\"PT5H\",\"branchExecTimeout\":\"PT6M\"}},{\"name\":\"LongDelayBranch\",\"actions\":[{\"subFlowRef\":{\"workflowId\":\"longdelayworkflowid\",\"invoke\":\"sync\",\"onParentComplete\":\"terminate\"},\"actionDataFilter\":{\"useResults\":true}}]}],\"completionType\":\"atLeast\",\"numCompleted\":13,\"timeouts\":{\"stateExecTimeout\":{\"single\":\"PT2S\",\"total\":\"PT1S\"},\"branchExecTimeout\":\"PT6M\"}}"))
 
 		// Switch State
-		assert.True(t, strings.Contains(string(b), "{\"name\":\"CheckVisaStatusSwitchEventBased\",\"type\":\"switch\",\"defaultCondition\":{\"transition\":{\"nextState\":\"HelloStateWithDefaultConditionString\"}},\"eventConditions\":[{\"name\":\"visaApprovedEvent\",\"eventRef\":\"visaApprovedEventRef\",\"metadata\":{\"mastercard\":\"disallowed\",\"visa\":\"allowed\"},\"end\":null,\"transition\":{\"nextState\":\"HandleApprovedVisa\"}},{\"eventRef\":\"visaRejectedEvent\",\"metadata\":{\"test\":\"tested\"},\"end\":null,\"transition\":{\"nextState\":\"HandleRejectedVisa\"}}],\"dataConditions\":null,\"timeouts\":{\"stateExecTimeout\":{\"single\":\"PT20S\",\"total\":\"PT10S\"},\"eventTimeout\":\"PT10H\"}}"))
+		assert.True(t, strings.Contains(string(b), "{\"name\":\"CheckVisaStatusSwitchEventBased\",\"type\":\"switch\",\"defaultCondition\":{\"transition\":{\"nextState\":\"HelloStateWithDefaultConditionString\"}},\"eventConditions\":[{\"name\":\"visaApprovedEvent\",\"eventRef\":\"visaApprovedEventRef\",\"metadata\":{\"mastercard\":\"disallowed\",\"visa\":\"allowed\"},\"transition\":{\"nextState\":\"HandleApprovedVisa\"}},{\"eventRef\":\"visaRejectedEvent\",\"metadata\":{\"test\":\"tested\"},\"transition\":{\"nextState\":\"HandleRejectedVisa\"}}],\"timeouts\":{\"stateExecTimeout\":{\"single\":\"PT20S\",\"total\":\"PT10S\"},\"eventTimeout\":\"PT10H\"}}"))
 
 		// Switch State with string DefaultCondition
-		assert.True(t, strings.Contains(string(b), "{\"name\":\"HelloStateWithDefaultConditionString\",\"type\":\"switch\",\"defaultCondition\":{\"transition\":{\"nextState\":\"SendTextForHighPriority\"}},\"eventConditions\":null,\"dataConditions\":[{\"condition\":\"${ true }\",\"end\":null,\"transition\":{\"nextState\":\"HandleApprovedVisa\"}},{\"condition\":\"${ false }\",\"end\":null,\"transition\":{\"nextState\":\"HandleRejectedVisa\"}}]}"))
+		assert.True(t, strings.Contains(string(b), "{\"name\":\"HelloStateWithDefaultConditionString\",\"type\":\"switch\",\"defaultCondition\":{\"transition\":{\"nextState\":\"SendTextForHighPriority\"}},\"dataConditions\":[{\"condition\":\"${ true }\",\"transition\":{\"nextState\":\"HandleApprovedVisa\"}},{\"condition\":\"${ false }\",\"transition\":{\"nextState\":\"HandleRejectedVisa\"}}]}"))
 
 		// Foreach State
 		assert.True(t, strings.Contains(string(b), "{\"name\":\"SendTextForHighPriority\",\"type\":\"foreach\",\"transition\":{\"nextState\":\"HelloInject\"},\"inputCollection\":\"${ .messages }\",\"outputCollection\":\"${ .outputMessages }\",\"iterationParam\":\"${ .this }\",\"batchSize\":45,\"actions\":[{\"name\":\"test\",\"functionRef\":{\"refName\":\"sendTextFunction\",\"arguments\":{\"message\":\"${ .singlemessage }\"},\"invoke\":\"sync\"},\"eventRef\":{\"triggerEventRef\":\"example1\",\"resultEventRef\":\"example2\",\"resultEventTimeout\":\"PT12H\",\"invoke\":\"sync\"},\"actionDataFilter\":{\"useResults\":true}}],\"mode\":\"sequential\",\"timeouts\":{\"stateExecTimeout\":{\"single\":\"PT22S\",\"total\":\"PT11S\"},\"actionExecTimeout\":\"PT11H\"}}"))