feat: support legacy microflow call web service statement

.claude/skills/mendix/write-microflows.md

@@ -728,6 +728,35 @@ retrieve $Items from Module.Entity where Active = true;
 
 **Note**: `returns type as $Var` in the microflow signature does NOT create an activity variable — it only names the return value. So `$Var = call java action ...` after `returns as $Var` is fine (one creation).
 
+## Legacy SOAP Web Service Calls
+
+`call web service` preserves legacy Mendix SOAP activities. Prefer REST clients
+for new integrations; this syntax exists mainly so existing projects can
+round-trip without dropping SOAP actions.
+
+```mdl
+-- Structured form. DESCRIBE prefers Module.Document names when references are resolvable.
+$Root = call web service 'SampleSOAP.OrderService'
+operation 'FetchSampleItems'
+send mapping 'SampleSOAP.OrderRequest'
+receive mapping 'SampleSOAP.OrderResponse'
+timeout 30
+on error rollback;
+
+-- Raw IDs are accepted when old project references are dangling or unavailable.
+$Root = call web service 'sample-service-id'
+operation 'FetchSampleItems'
+send mapping 'sample-send-mapping-id'
+receive mapping 'sample-receive-mapping-id';
+
+-- Raw escape hatch emitted for unsupported SOAP fields.
+$Root = call web service raw 'AQID';
+```
+
+**Design note:** the raw payload is base64-encoded BSON for the complete action
+and is authoritative on re-exec. Treat this as round-trip support, not a
+recommended authoring format for new integrations.
+
 ## REST Service Calls
 
 MDL supports two patterns for calling REST APIs from microflows:

docs/01-project/MDL_QUICK_REFERENCE.md

@@ -223,6 +223,8 @@ authentication basic, session
 | Retrieve (Assoc) | `retrieve $list from $Parent/Module.AssocName;` | Retrieve by association |
 | Call microflow | `$Result = call microflow Module.Name (Param = $value);` | |
 | Call nanoflow | `$Result = call nanoflow Module.Name (Param = $value);` | |
+| Call web service | `$Result = call web service 'Module.Service' operation 'OperationName';` | Legacy SOAP; unresolved dangling refs fall back to raw IDs |
+| Call web service raw | `$Result = call web service raw 'base64-bson';` | Escape hatch for byte-for-byte legacy SOAP round-trip |
 | Show page | `show page Module.PageName ($Param = $value);` | Also accepts `(Param: $value)` |
 | Close page | `close page;` | |
 | Validation | `validation feedback $entity/attribute message 'message';` | Requires attribute path + MESSAGE |

docs/11-proposals/PROPOSAL_microflow_call_web_service_statement.md

@@ -0,0 +1,90 @@
+# Microflow Call Web Service Statement
+
+Status: Draft
+
+## Summary
+
+Add MDL support for legacy Mendix SOAP `Microflows$CallWebServiceAction`.
+
+```mdl
+$Root = call web service 'SampleSOAP.OrderService'
+operation 'FetchSampleItems'
+send mapping 'SampleSOAP.OrderRequest'
+receive mapping 'SampleSOAP.OrderResponse'
+timeout 30;
+
+$Root = call web service 'dangling-service-id'
+operation 'FetchSampleItems'
+send mapping 'dangling-send-mapping-id'
+receive mapping 'dangling-receive-mapping-id';
+
+$Root = call web service raw 'AQID';
+```
+
+This proposal is primarily about safe round-trip preservation of existing SOAP
+actions. New integrations should prefer consumed REST services or inline REST
+calls.
+
+## Motivation
+
+Legacy projects can contain SOAP web service calls. Without an MDL
+representation, describe output either drops the activity or emits an
+unsupported-action comment that cannot be re-executed into the same model.
+
+The immediate goal is therefore fidelity:
+
+- Parse existing `CallWebServiceAction` BSON.
+- Emit an MDL statement that can be executed back into the MPR.
+- Preserve unsupported or version-specific BSON fields when the structured
+  fields are incomplete.
+
+## Syntax
+
+```antlr
+callWebServiceStatement
+    : (VARIABLE EQUALS)? CALL WEB SERVICE
+      (RAW STRING_LITERAL
+      | STRING_LITERAL
+        (OPERATION STRING_LITERAL)?
+        (SEND MAPPING STRING_LITERAL)?
+        (RECEIVE MAPPING STRING_LITERAL)?
+        (TIMEOUT expression)?)
+      onErrorClause?
+    ;
+```
+
+## Design Notes
+
+The structured form prefers stable qualified names for the imported web service
+and mapping references. During `describe`, mxcli resolves known
+`WebServices$ImportedWebService`, `ExportMappings$ExportMapping`, and
+`ImportMappings$ImportMapping` IDs through the backend and emits
+`Module.DocumentName`.
+
+If a reference is dangling or the backend cannot resolve it, mxcli deliberately
+falls back to the raw ID string so unsupported legacy projects still round-trip.
+
+The `raw` form is an explicit escape hatch. Its string is base64-encoded BSON
+for the complete action payload and is authoritative when re-executed. It exists
+so unsupported SOAP fields can be preserved byte-for-byte until the structured
+syntax covers them.
+
+## Tests And Examples
+
+- Parser/visitor coverage for structured and raw forms.
+- Builder/writer coverage for real `WebServiceCallAction` construction and raw
+  BSON preservation.
+- Formatter coverage for qualified-name resolution and raw-ID fallback.
+- Example script: `mdl-examples/doctype-tests/call_web_service.test.mdl`.
+
+## Resolved Questions
+
+- Service and mapping references are emitted as `Module.Document` names when
+  the backend can resolve them. Raw IDs remain the fallback for dangling
+  references and incomplete project metadata.
+
+## Open Questions
+
+- Should the raw payload eventually move to a generic
+  `raw microflow action '...'` escape hatch instead of remaining under
+  `call web service raw`?

docs/11-proposals/README.md

@@ -43,6 +43,7 @@ BSON schema Registry ◄──── multi-version Support
 |----------|--------|---------|------------|
 | [MDL Syntax Improvements v1](PROPOSAL_mdl_syntax_improvements.md) | Draft | Go-style assignment, C-style braces, fluent list APIs | — |
 | [MDL Syntax Improvements v2](PROPOSAL_mdl_syntax_improvements_v2.md) | Proposed | Consolidated v2: unified variable declaration, C-style braces, fluent list ops | Syntax Improvements v1 |
+| [Microflow Call Web Service Statement](PROPOSAL_microflow_call_web_service_statement.md) | Draft | Structured and raw MDL syntax for legacy SOAP `CallWebServiceAction` round-trip preservation | — |
 | [Page Syntax V2](PROPOSAL_page_syntax_v2.md) | Superseded | Page/widget syntax with `{}` blocks and `->` binding. Superseded by V3 (archived) | — |
 | [Page Styling Support](page-styling-support.md) | Partial | CSS classes, inline styles, dynamic classes, design properties. Phase 1 (Class/Style) done | — |
 | [Page Composition](proposal_page_composition.md) | Proposed | Fragment definitions and ALTER PAGE for partial page editing | Page Syntax V2, Page Styling |

mdl-examples/doctype-tests/call_web_service.test.mdl

@@ -0,0 +1,42 @@
+create module SampleSOAP;
+
+create entity SampleSOAP.OrderResponse (
+  Status : string(50)
+);
+/
+
+create microflow SampleSOAP.ACT_FetchItems ()
+returns SampleSOAP.OrderResponse as $Root
+begin
+  $Root = call web service 'SampleSOAP.OrderService'
+  operation 'FetchSampleItems'
+  send mapping 'SampleSOAP.OrderRequest'
+  receive mapping 'SampleSOAP.OrderResponse'
+  timeout 30
+  on error rollback;
+
+  return $Root;
+end;
+/
+
+create microflow SampleSOAP.ACT_FetchItemsDanglingRefs ()
+returns SampleSOAP.OrderResponse as $Root
+begin
+  -- Raw IDs are preserved when describe cannot resolve dangling legacy refs.
+  $Root = call web service 'sample-service-id'
+  operation 'FetchSampleItems'
+  send mapping 'sample-send-mapping-id'
+  receive mapping 'sample-receive-mapping-id';
+
+  return $Root;
+end;
+/
+
+create microflow SampleSOAP.ACT_FetchItemsRaw ()
+begin
+  -- Raw base64 escape hatch: opaque Microflows$CallWebServiceAction BSON is
+  -- preserved verbatim. The encoded payload here has no OutputVariable, so
+  -- no `$Var = ` assignment is emitted; richer payloads can carry one.
+  call web service raw 'uAAAAAIkSUQAGgAAAHNhbXBsZS13ZWItc2VydmljZS1hY3Rpb24AAiRUeXBlACAAAABNaWNyb2Zsb3dzJENhbGxXZWJTZXJ2aWNlQWN0aW9uAAJJbXBvcnRlZFNlcnZpY2UAEgAAAHNhbXBsZS1zZXJ2aWNlLWlkAAJPcGVyYXRpb25OYW1lABEAAABGZXRjaFNhbXBsZUl0ZW1zAAJUaW1lT3V0RXhwcmVzc2lvbgADAAAAMzAAAA==';
+end;
+/

mdl/ast/ast_microflow.go

@@ -334,6 +334,21 @@ type CallJavaActionStmt struct {
 
 func (s *CallJavaActionStmt) isMicroflowStatement() {}
 
+// CallWebServiceStmt represents a legacy SOAP web service call.
+type CallWebServiceStmt struct {
+	OutputVariable   string               // Optional output variable
+	RawBSONBase64    string               // Raw Microflows$CallWebServiceAction BSON for lossless roundtrip
+	ServiceID        string               // Consumed web service ID or qualified name
+	OperationName    string               // Operation name
+	SendMappingID    string               // Optional export mapping ID or qualified name
+	ReceiveMappingID string               // Optional import mapping ID or qualified name
+	Timeout          Expression           // Optional timeout expression
+	ErrorHandling    *ErrorHandlingClause // Optional ON ERROR clause
+	Annotations      *ActivityAnnotations // Optional @position, @caption, @color, @annotation
+}
+
+func (s *CallWebServiceStmt) isMicroflowStatement() {}
+
 // ExecuteDatabaseQueryStmt represents: EXECUTE DATABASE QUERY Module.Connection.QueryName ...
 type ExecuteDatabaseQueryStmt struct {
 	OutputVariable      string               // Optional output variable

mdl/executor/cmd_microflows_builder_annotations.go

@@ -45,6 +45,8 @@ func getStatementAnnotations(stmt ast.MicroflowStatement) *ast.ActivityAnnotatio
 		return s.Annotations
 	case *ast.CallJavaActionStmt:
 		return s.Annotations
+	case *ast.CallWebServiceStmt:
+		return s.Annotations
 	case *ast.ExecuteDatabaseQueryStmt:
 		return s.Annotations
 	case *ast.CallExternalActionStmt:

mdl/executor/cmd_microflows_builder_calls.go

@@ -4,6 +4,7 @@
 package executor
 
 import (
+	"encoding/base64"
 	"fmt"
 	"log"
 	"strings"
@@ -268,6 +269,112 @@ func (fb *flowBuilder) addCallJavaActionAction(s *ast.CallJavaActionStmt) model.
 	return activity.ID
 }
 
+// addCallWebServiceAction creates a legacy SOAP WebServiceCallAction.
+func (fb *flowBuilder) addCallWebServiceAction(s *ast.CallWebServiceStmt) model.ID {
+	activityX := fb.posX
+	action := &microflows.WebServiceCallAction{
+		BaseElement:       model.BaseElement{ID: model.ID(types.GenerateID())},
+		ErrorHandlingType: convertErrorHandlingType(s.ErrorHandling),
+		ServiceID:         model.ID(fb.resolveWebServiceRefForWrite(s.ServiceID)),
+		OperationName:     s.OperationName,
+		SendMappingID:     model.ID(fb.resolveMappingRefForWrite(s.SendMappingID, true)),
+		ReceiveMappingID:  model.ID(fb.resolveMappingRefForWrite(s.ReceiveMappingID, false)),
+		OutputVariable:    s.OutputVariable,
+		UseReturnVariable: s.OutputVariable != "",
+	}
+	if s.RawBSONBase64 != "" {
+		raw, err := base64.StdEncoding.DecodeString(s.RawBSONBase64)
+		if err != nil {
+			fb.addError("invalid raw web service action payload: %v", err)
+		} else {
+			action.RawBSON = raw
+		}
+	}
+	if s.Timeout != nil {
+		action.TimeoutExpression = fb.exprToString(s.Timeout)
+	}
+
+	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,
+			ErrorHandlingType:   convertErrorHandlingType(s.ErrorHandling),
+		},
+		Action: action,
+	}
+
+	fb.objects = append(fb.objects, activity)
+	fb.posX += fb.spacing
+
+	if s.OutputVariable != "" && fb.declaredVars != nil {
+		fb.declaredVars[s.OutputVariable] = "Unknown"
+	}
+
+	if s.ErrorHandling != nil && len(s.ErrorHandling.Body) > 0 {
+		errorY := fb.posY + VerticalSpacing
+		mergeID := fb.addErrorHandlerFlow(activity.ID, activityX, s.ErrorHandling.Body)
+		fb.handleErrorHandlerMerge(mergeID, activity.ID, errorY)
+	}
+
+	return activity.ID
+}
+
+func (fb *flowBuilder) resolveWebServiceRefForWrite(ref string) string {
+	if ref == "" || !strings.Contains(ref, ".") || fb.backend == nil {
+		return ref
+	}
+	units, err := fb.backend.ListRawUnitsByType("WebServices$ImportedWebService")
+	if err != nil {
+		return ref
+	}
+	for _, unit := range units {
+		if unit == nil {
+			continue
+		}
+		name := rawUnitName(unit.Contents)
+		if name == "" {
+			continue
+		}
+		if fb.hierarchy != nil && fb.hierarchy.GetQualifiedName(unit.ContainerID, name) == ref {
+			return string(unit.ID)
+		}
+		if name == ref {
+			return string(unit.ID)
+		}
+	}
+	return ref
+}
+
+func (fb *flowBuilder) resolveMappingRefForWrite(ref string, preferExport bool) string {
+	if ref == "" || !strings.Contains(ref, ".") || fb.backend == nil {
+		return ref
+	}
+	moduleName, name, ok := strings.Cut(ref, ".")
+	if !ok || moduleName == "" || name == "" {
+		return ref
+	}
+	if preferExport {
+		if mapping, err := fb.backend.GetExportMappingByQualifiedName(moduleName, name); err == nil && mapping != nil {
+			return string(mapping.ID)
+		}
+		if mapping, err := fb.backend.GetImportMappingByQualifiedName(moduleName, name); err == nil && mapping != nil {
+			return string(mapping.ID)
+		}
+	} else {
+		if mapping, err := fb.backend.GetImportMappingByQualifiedName(moduleName, name); err == nil && mapping != nil {
+			return string(mapping.ID)
+		}
+		if mapping, err := fb.backend.GetExportMappingByQualifiedName(moduleName, name); err == nil && mapping != nil {
+			return string(mapping.ID)
+		}
+	}
+	return ref
+}
+
 // addCallExternalActionAction creates a CALL EXTERNAL ACTION statement.
 func (fb *flowBuilder) addCallExternalActionAction(s *ast.CallExternalActionStmt) model.ID {
 	serviceQN := s.ServiceName.Module + "." + s.ServiceName.Name

mdl/executor/cmd_microflows_builder_graph.go

@@ -222,6 +222,8 @@ func (fb *flowBuilder) addStatement(stmt ast.MicroflowStatement) model.ID {
 		return fb.addCallMicroflowAction(s)
 	case *ast.CallJavaActionStmt:
 		return fb.addCallJavaActionAction(s)
+	case *ast.CallWebServiceStmt:
+		return fb.addCallWebServiceAction(s)
 	case *ast.ExecuteDatabaseQueryStmt:
 		return fb.addExecuteDatabaseQueryAction(s)
 	case *ast.CallExternalActionStmt:

mdl/executor/cmd_microflows_builder_validate.go

@@ -148,6 +148,14 @@ func (fb *flowBuilder) validateStatement(stmt ast.MicroflowStatement) {
 			fb.validateStatements(s.ErrorHandling.Body)
 		}
 
+	case *ast.CallWebServiceStmt:
+		if s.OutputVariable != "" {
+			fb.declaredVars[s.OutputVariable] = "Unknown"
+		}
+		if s.ErrorHandling != nil && len(s.ErrorHandling.Body) > 0 {
+			fb.validateStatements(s.ErrorHandling.Body)
+		}
+
 	case *ast.ExecuteDatabaseQueryStmt:
 		if s.OutputVariable != "" {
 			fb.declaredVars[s.OutputVariable] = "Unknown"