Add .env option to disable runtime WF stacktrace

.env.example

@@ -1223,6 +1223,12 @@
 # Default: <no value>
 # WORKFLOW_CALL_STACK_SIZE=<no value>
 
+###############################################################################
+# Enables execution stack trace construction
+# Type:    bool
+# Default: <no value>
+# WORKFLOW_STACK_TRACE_ENABLED=<no value>
+
 ###############################################################################
 ###############################################################################
 # Discovery

app/options/workflow.cue

@@ -21,6 +21,11 @@ workflow: schema.#optionsGroup & {
 			defaultGoExpr: "16"
 			description:   "Defines the maximum call stack size between workflows"
 		}
+		stack_trace_enabled: {
+			type:          "bool"
+			defaultGoExpr: "true"
+			description:   "Enables execution stack trace construction"
+		}
 	}
 	title: "Workflow"
 }

automation/service/session.go

@@ -285,6 +285,9 @@ func (svc *session) spawn(g *wfexec.Graph, workflowID uint64, trace bool, callSt
 
 	// blocks until session is set
 	ses = types.NewSession(<-s.session)
+	if !svc.opt.StackTraceEnabled {
+		ses.DisableStacktrace()
+	}
 
 	svc.mux.Lock()
 	svc.pool[ses.ID] = ses

automation/types/session.go

@@ -15,6 +15,10 @@ import (
 )
 
 type (
+	runtimeOptions struct {
+		disableStacktrace bool
+	}
+
 	// Instance of single workflow execution
 	Session struct {
 		ID         uint64 `json:"sessionID,string"`
@@ -43,6 +47,8 @@ type (
 
 		session *wfexec.Session
 
+		runtimeOpts runtimeOptions `json:"-"`
+
 		// For keeping runtime stacktrace,
 		// even if we do not want to store it on every update
 		//
@@ -112,6 +118,10 @@ func NewSession(s *wfexec.Session) *Session {
 	}
 }
 
+func (s *Session) DisableStacktrace() {
+	s.runtimeOpts.disableStacktrace = true
+}
+
 func (s *Session) Exec(ctx context.Context, step wfexec.Step, input *expr.Vars) error {
 	return s.session.Exec(ctx, step, input)
 }
@@ -165,10 +175,12 @@ func (s *Session) Apply(ssp SessionStartParams) {
 }
 
 func (s *Session) AppendRuntimeStacktrace(frame *wfexec.Frame) {
-	s.l.RLock()
-	defer s.l.RUnlock()
+	if !s.runtimeOpts.disableStacktrace {
+		s.l.RLock()
+		defer s.l.RUnlock()
 
-	s.RuntimeStacktrace = append(s.RuntimeStacktrace, frame)
+		s.RuntimeStacktrace = append(s.RuntimeStacktrace, frame)
+	}
 }
 
 func (s *Session) CopyRuntimeStacktrace() {

pkg/options/options.gen.go

@@ -252,9 +252,10 @@ type (
 	}
 
 	WorkflowOpt struct {
-		Register      bool `env:"WORKFLOW_REGISTER"`
-		ExecDebug     bool `env:"WORKFLOW_EXEC_DEBUG"`
-		CallStackSize int  `env:"WORKFLOW_CALL_STACK_SIZE"`
+		Register          bool `env:"WORKFLOW_REGISTER"`
+		ExecDebug         bool `env:"WORKFLOW_EXEC_DEBUG"`
+		CallStackSize     int  `env:"WORKFLOW_CALL_STACK_SIZE"`
+		StackTraceEnabled bool `env:"WORKFLOW_STACK_TRACE_ENABLED"`
 	}
 
 	DiscoveryOpt struct {
@@ -1066,8 +1067,9 @@ func Websocket() (o *WebsocketOpt) {
 // This function is auto-generated
 func Workflow() (o *WorkflowOpt) {
 	o = &WorkflowOpt{
-		Register:      true,
-		CallStackSize: 16,
+		Register:          true,
+		CallStackSize:     16,
+		StackTraceEnabled: true,
 	}
 
 	// Custom defaults