feat: CALL NANOFLOW + GRANT/REVOKE nanoflow access by retran · Pull Request #8 · retran/mxcli

retran · 2026-04-23T16:25:53Z

Summary

Add CALL NANOFLOW statement for calling nanoflows from within flow bodies (grammar, AST, visitor, flow builder, validation)
Add GRANT/REVOKE EXECUTE ON NANOFLOW for nanoflow security management (grammar, AST, visitor, executor)
Add NanoflowCallAction, NanoflowCall, NanoflowCallParameterMapping SDK types with BSON parser/writer
Add AllowedModuleRoles to Nanoflow struct with BSON round-trip support
Add cross-reference validation for nanoflow calls in validate.go
Add write-nanoflows.md agentic skill (embedded in binary)
Add comprehensive nanoflow proposal doc (PROPOSAL_nanoflow_support.md)

Why

Completes P1 nanoflow parity: without CALL NANOFLOW, nanoflows cannot invoke other nanoflows — breaking compositional flow design. Without GRANT/REVOKE, security roles cannot be managed via CLI. The agentic skill enables LLM agents to write correct nanoflow MDL without microflow-only action mistakes.

Testing

make build && make test && make lint-go all pass
Registry test updated with all new AST types
Formatting stash from earlier PRs not included (separate concern)

Copilot

Pull request overview

Adds nanoflow composition and security management to MDL/mxcli by introducing CALL NANOFLOW within flow bodies and GRANT/REVOKE EXECUTE ON NANOFLOW, plus the SDK/BSON plumbing and executor validation needed to round-trip these constructs.

Changes:

Extend MDL grammar/AST/visitor to support CALL NANOFLOW and GRANT/REVOKE EXECUTE ON NANOFLOW.
Add SDK types + BSON parser/writer support for NanoflowCallAction and Nanoflow.AllowedModuleRoles.
Update executor flow builder + validation to build/validate nanoflow calls and nanoflow access statements; add docs/skills.

Reviewed changes

Copilot reviewed 32 out of 43 changed files in this pull request and generated 3 comments.

Show a summary per file

File	Description
sdk/mpr/writer_microflow_actions.go	Serialize `Microflows$NanoflowCallAction` + nested call/mappings to BSON.
sdk/mpr/writer_microflow.go	Serialize `Nanoflow.AllowedModuleRoles` in nanoflow BSON.
sdk/mpr/parser_nanoflow.go	Parse `AllowedModuleRoles` from nanoflow BSON.
sdk/mpr/parser_microflow_actions.go	Parse `Microflows$NanoflowCallAction` and nested structures.
sdk/mpr/parser_microflow.go	Register parser for `Microflows$NanoflowCallAction`.
sdk/microflows/microflows_actions.go	Add SDK model types: `NanoflowCallAction`, `NanoflowCall`, `NanoflowCallParameterMapping`.
sdk/microflows/microflows.go	Add `AllowedModuleRoles` to `Nanoflow` SDK struct.
mdl/visitor/visitor_security.go	Build AST for GRANT/REVOKE nanoflow access statements.
mdl/visitor/visitor_microflow_statements.go	Dispatch + annotation wiring for `CallNanoflowStmt`.
mdl/visitor/visitor_microflow_actions.go	Build `CallNanoflowStmt` from parser context.
mdl/grammar/parser/mdlparser_listener.go	Regenerated listener interface for new productions.
mdl/grammar/parser/mdlparser_base_listener.go	Regenerated base listener stubs for new productions.
mdl/grammar/MDLParser.g4	Grammar additions: `callNanoflowStatement`, `grantNanoflowAccessStatement`, `revokeNanoflowAccessStatement`.
mdl/executor/validate_microflow.go	Treat `CallNanoflowStmt` like other call statements for variable/error-handling validation.
mdl/executor/validate.go	Track nanoflow definitions + validate `call nanoflow` references in flow bodies.
mdl/executor/stmt_summary.go	Add summaries for GRANT/REVOKE nanoflow access statements.
mdl/executor/registry_test.go	Register new statement types in registry completeness tests.
mdl/executor/register_stubs.go	Register executor handlers for GRANT/REVOKE nanoflow access.
mdl/executor/nanoflow_validation.go	Include `CallNanoflowStmt` in nanoflow error-handling traversal.
mdl/executor/hierarchy.go	Remove trailing whitespace (no functional change).
mdl/executor/cmd_security_write.go	Implement GRANT/REVOKE nanoflow execute access by updating allowed roles.
mdl/executor/cmd_microflows_builder_validate.go	Track output var typing + validate error handler body for `CallNanoflowStmt`.
mdl/executor/cmd_microflows_builder_graph.go	Flow builder dispatch to create nanoflow call action.
mdl/executor/cmd_microflows_builder_calls.go	Build `NanoflowCallAction` + mappings + output variable integration.
mdl/executor/cmd_microflows_builder_annotations.go	Expose annotations for `CallNanoflowStmt`.
mdl/executor/cmd_microflows_builder.go	Lookup nanoflow return type via backend for typing inference.
mdl/executor/cmd_diff_mdl.go	Render `CallNanoflowStmt` into MDL for diff output.
mdl/catalog/builder_microflows_test.go	Import order formatting (no functional change).
mdl/catalog/builder.go	Alignment/formatting change only.
mdl/ast/ast_security.go	Add AST nodes for GRANT/REVOKE nanoflow access.
mdl/ast/ast_microflow.go	Add AST node `CallNanoflowStmt`.
docs/11-proposals/PROPOSAL_nanoflow_support.md	Add comprehensive nanoflow support proposal doc.
cmd/mxcli/syntax/registry.go	Whitespace/alignment only (no behavior change).
cmd/mxcli/syntax/features_workflow.go	Whitespace/alignment only (no behavior change).
cmd/mxcli/syntax/features_security.go	Whitespace/alignment only (no behavior change).
cmd/mxcli/syntax/features_page.go	Whitespace/alignment only (no behavior change).
cmd/mxcli/syntax/features_misc.go	Whitespace/alignment only (no behavior change).
cmd/mxcli/syntax/features_microflow.go	Whitespace/alignment only (no behavior change).
cmd/mxcli/syntax/features_integration.go	Whitespace/alignment only (no behavior change).
cmd/mxcli/syntax/features_domain_model.go	Whitespace/alignment only (no behavior change).
.claude/skills/mendix/write-nanoflows.md	Add agent skill guidance for writing nanoflows, including CALL + security.

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Copilot · 2026-04-23T16:33:00Z

+// addCallNanoflowAction creates a CALL NANOFLOW statement.
+func (fb *flowBuilder) addCallNanoflowAction(s *ast.CallNanoflowStmt) model.ID {
+	nfQN := s.NanoflowName.Module + "." + s.NanoflowName.Name
+
+	// Build parameter mappings for NanoflowCall
+	var mappings []*microflows.NanoflowCallParameterMapping
+	for _, arg := range s.Arguments {
+		paramQN := nfQN + "." + arg.Name
+		mapping := &microflows.NanoflowCallParameterMapping{
+			BaseElement: model.BaseElement{ID: model.ID(types.GenerateID())},
+			Parameter:   paramQN,
+			Argument:    fb.exprToString(arg.Value),
+		}
+		mappings = append(mappings, mapping)
+	}
+
+	nfCall := &microflows.NanoflowCall{
+		BaseElement:       model.BaseElement{ID: model.ID(types.GenerateID())},
+		Nanoflow:          nfQN,
+		ParameterMappings: mappings,
+	}
+
+	action := &microflows.NanoflowCallAction{
+		BaseElement:        model.BaseElement{ID: model.ID(types.GenerateID())},
+		ErrorHandlingType:  convertErrorHandlingType(s.ErrorHandling),
+		NanoflowCall:       nfCall,
+		ResultVariableName: s.OutputVariable,
+		UseReturnVariable:  s.OutputVariable != "",
+	}


addCallNanoflowAction emits a *microflows.NanoflowCallAction, but the MDL formatter used by DESCRIBE NANOFLOW (formatAction in cmd_microflows_format_action.go) currently has no case for NanoflowCallAction, so describing a nanoflow containing this statement will render as an unsupported/unknown action. Add formatting support for NanoflowCallAction (and its parameter mappings + optional result variable) so describe output round-trips the new syntax.

Copilot · 2026-04-23T16:33:00Z

    | annotation* raiseErrorStatement SEMICOLON?
    | annotation* logStatement SEMICOLON?
    | annotation* callMicroflowStatement SEMICOLON?
+    | annotation* callNanoflowStatement SEMICOLON?
    | annotation* callJavaActionStatement SEMICOLON?


microflowStatement is used by both microflow and nanoflow bodies (via microflowBody). Adding callNanoflowStatement here makes CALL NANOFLOW syntactically valid inside microflows as well. This conflicts with the PR’s own nanoflow skill/proposal text stating microflows can’t call nanoflows; either move this alternative to a nanoflow-only statement rule, or add explicit validation in microflow creation/validation to reject CallNanoflowStmt in microflows (and update docs if the intent is actually to allow it).

Copilot · 2026-04-23T16:33:01Z

+// addCallNanoflowAction creates a CALL NANOFLOW statement.
+func (fb *flowBuilder) addCallNanoflowAction(s *ast.CallNanoflowStmt) model.ID {
+	nfQN := s.NanoflowName.Module + "." + s.NanoflowName.Name
+
+	// Build parameter mappings for NanoflowCall
+	var mappings []*microflows.NanoflowCallParameterMapping
+	for _, arg := range s.Arguments {
+		paramQN := nfQN + "." + arg.Name
+		mapping := &microflows.NanoflowCallParameterMapping{
+			BaseElement: model.BaseElement{ID: model.ID(types.GenerateID())},
+			Parameter:   paramQN,
+			Argument:    fb.exprToString(arg.Value),
+		}
+		mappings = append(mappings, mapping)
+	}
+
+	nfCall := &microflows.NanoflowCall{
+		BaseElement:       model.BaseElement{ID: model.ID(types.GenerateID())},
+		Nanoflow:          nfQN,
+		ParameterMappings: mappings,
+	}
+
+	action := &microflows.NanoflowCallAction{
+		BaseElement:        model.BaseElement{ID: model.ID(types.GenerateID())},
+		ErrorHandlingType:  convertErrorHandlingType(s.ErrorHandling),
+		NanoflowCall:       nfCall,
+		ResultVariableName: s.OutputVariable,
+		UseReturnVariable:  s.OutputVariable != "",
+	}
+
+	activityX := fb.posX
+	activity := &microflows.ActionActivity{
+		BaseActivity: microflows.BaseActivity{
+			BaseMicroflowObject: microflows.BaseMicroflowObject{
+				BaseElement: model.BaseElement{ID: model.ID(types.GenerateID())},
+				Position:    model.Point{X: fb.posX, Y: fb.posY},
+				Size:        model.Size{Width: ActivityWidth, Height: ActivityHeight},
+			},
+			AutoGenerateCaption: true,
+		},
+		Action: action,
+	}
+
+	fb.objects = append(fb.objects, activity)
+	fb.posX += fb.spacing
+
+	if s.OutputVariable != "" {
+		fb.registerResultVariableType(s.OutputVariable, fb.lookupNanoflowReturnType(nfQN))
+	}


There are existing unit tests covering addCallMicroflowAction result typing/behavior, but no analogous coverage for addCallNanoflowAction (e.g., parameter mapping format, UseReturnVariable/ResultVariableName, and return-type inference via lookupNanoflowReturnType). Adding targeted tests will help prevent regressions in CALL NANOFLOW serialization and type tracking.

Copilot

Pull request overview

Copilot reviewed 32 out of 35 changed files in this pull request and generated 4 comments.

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Copilot · 2026-04-23T19:50:26Z

+	model.BaseElement
+	ErrorHandlingType  ErrorHandlingType `json:"errorHandlingType,omitempty"`
+	NanoflowCall       *NanoflowCall     `json:"nanoflowCall,omitempty"`
+	ResultVariableName string            `json:"resultVariableName,omitempty"`


NanoflowCallAction uses ResultVariableName/resultVariableName naming, but the repository’s generated Mendix metamodel represents Microflows$NanoflowCallAction with an OutputVariableName field (json:"outputVariableName"). If the BSON field is also OutputVariableName, the current SDK type + BSON reader/writer will silently drop result variable assignments. Align the SDK field name/tag (and corresponding BSON keys in parser/writer) with the metamodel for nanoflow calls.

Suggested change

ResultVariableName string `json:"resultVariableName,omitempty"`

OutputVariableName string `json:"outputVariableName,omitempty"`

Copilot · 2026-04-23T19:50:26Z

+		doc := bson.D{
+			{Key: "$ID", Value: idToBsonBinary(string(a.ID))},
+			{Key: "$Type", Value: "Microflows$NanoflowCallAction"},
+			{Key: "ErrorHandlingType", Value: stringOrDefault(string(a.ErrorHandlingType), "Rollback")},
+			{Key: "ResultVariableName", Value: a.ResultVariableName},
+			{Key: "UseReturnVariable", Value: a.UseReturnVariable},
+		}


serializeMicroflowAction writes NanoflowCallAction using the BSON key ResultVariableName. The generated metamodel indicates Microflows$NanoflowCallAction uses OutputVariableName (and JSON outputVariableName), so this may emit invalid/ignored output-variable data in Studio Pro. Verify the correct storage field name for nanoflow call actions and update the writer (and parser/types) accordingly.

Copilot · 2026-04-23T19:50:26Z

+func parseNanoflowCallAction(raw map[string]any) *microflows.NanoflowCallAction {
+	action := &microflows.NanoflowCallAction{}
+	action.ID = model.ID(extractBsonID(raw["$ID"]))
+	action.ErrorHandlingType = microflows.ErrorHandlingType(extractString(raw["ErrorHandlingType"]))
+	action.ResultVariableName = extractString(raw["ResultVariableName"])
+	action.UseReturnVariable = extractBool(raw["UseReturnVariable"], false)
+


parseNanoflowCallAction reads the result variable from raw["ResultVariableName"]. If Mendix stores nanoflow call output variables under OutputVariableName (per generated metamodel), this will parse as empty and break round-tripping. Consider checking both keys (similar to other parsers that handle storageName vs qualifiedName differences) or switching to the correct key consistently with the writer.

Copilot · 2026-04-23T19:50:27Z

+	// Parse AllowedModuleRoles
+	for _, r := range extractBsonArray(raw["AllowedModuleRoles"]) {
+		if roleID, ok := r.(string); ok {
+			nf.AllowedModuleRoles = append(nf.AllowedModuleRoles, model.ID(roleID))
+		}
+	}


The loop variable r in for _, r := range extractBsonArray(...) shadows the method receiver r *Reader, which makes the code harder to read and easy to trip over during future edits. Renaming the loop variable (e.g., role/item) would avoid the shadowing without changing behavior.

… and proposal

Copilot AI review requested due to automatic review settings April 23, 2026 16:25

Copilot started reviewing on behalf of retran April 23, 2026 16:26 View session

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retran force-pushed the pr5-nanoflows-call-grant branch from 2dee3d2 to 54a9353 Compare April 23, 2026 16:50

retran force-pushed the pr4-nanoflows-create-drop branch from 2356562 to 4588cda Compare April 23, 2026 19:42

retran force-pushed the pr5-nanoflows-call-grant branch from 82247b4 to 2183899 Compare April 23, 2026 19:42

retran requested a review from Copilot April 23, 2026 19:42

Copilot started reviewing on behalf of retran April 23, 2026 19:43 View session

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retran force-pushed the pr4-nanoflows-create-drop branch from 4588cda to bc2a53a Compare April 23, 2026 20:11

retran force-pushed the pr5-nanoflows-call-grant branch from 2183899 to bcb19c0 Compare April 23, 2026 20:11

feat: add CALL NANOFLOW, GRANT/REVOKE nanoflow access, agentic skill,…

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… and proposal

retran force-pushed the pr4-nanoflows-create-drop branch from bc2a53a to dabcdfb Compare April 23, 2026 20:28

retran force-pushed the pr5-nanoflows-call-grant branch from bcb19c0 to dd4df09 Compare April 23, 2026 20:28

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feat: CALL NANOFLOW + GRANT/REVOKE nanoflow access#8

feat: CALL NANOFLOW + GRANT/REVOKE nanoflow access#8
retran wants to merge 1 commit intopr4-nanoflows-create-dropfrom
pr5-nanoflows-call-grant

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	ResultVariableName string `json:"resultVariableName,omitempty"`
	OutputVariableName string `json:"outputVariableName,omitempty"`

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retran commented Apr 23, 2026

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