Harden validation error recovery

backend/src/main/java/fr/nessar/lmnporganizer/rental/adapter/in/web/common/RentalApiExceptionHandler.java

@@ -19,10 +19,14 @@ import org.slf4j.LoggerFactory;
 import org.springframework.dao.OptimisticLockingFailureException;
 import org.springframework.http.HttpStatus;
 import org.springframework.http.ResponseEntity;
+import org.springframework.http.converter.HttpMessageNotReadableException;
 import org.springframework.web.bind.MethodArgumentNotValidException;
+import org.springframework.web.bind.MissingServletRequestParameterException;
 import org.springframework.web.bind.annotation.ExceptionHandler;
 import org.springframework.web.bind.annotation.RestControllerAdvice;
+import org.springframework.web.method.annotation.MethodArgumentTypeMismatchException;
 import org.springframework.web.multipart.MaxUploadSizeExceededException;
+import org.springframework.web.multipart.support.MissingServletRequestPartException;
 
 @RestControllerAdvice(basePackages = "fr.nessar.lmnporganizer.rental.adapter.in.web")
 public class RentalApiExceptionHandler {
@@ -93,6 +97,27 @@ ResponseEntity<ValidationApiError> invalidRequest(MethodArgumentNotValidExceptio
 					.toList()));
 }
 
+@ExceptionHandler(HttpMessageNotReadableException.class)
+ResponseEntity<ValidationApiError> unreadableRequest() {
+	return validation("request", "malformed");
+}
+
+@ExceptionHandler(MethodArgumentTypeMismatchException.class)
+ResponseEntity<ValidationApiError> invalidParameter(MethodArgumentTypeMismatchException exception) {
+	return validation(exception.getName(), "invalid");
+}
+
+@ExceptionHandler(MissingServletRequestParameterException.class)
+ResponseEntity<ValidationApiError> missingParameter(
+	MissingServletRequestParameterException exception) {
+	return validation(exception.getParameterName(), "required");
+}
+
+@ExceptionHandler(MissingServletRequestPartException.class)
+ResponseEntity<ValidationApiError> missingPart(MissingServletRequestPartException exception) {
+	return validation(exception.getRequestPartName(), "required");
+}
+
 @ExceptionHandler(Exception.class)
 ResponseEntity<ApiError> unexpected(Exception exception) {
 	LOGGER.error("Unhandled rental API exception", exception);
@@ -107,6 +132,13 @@ private static ResponseEntity<ApiError> error(HttpStatus status, String message)
 	return ResponseEntity.status(status).body(new ApiError(message));
 }
 
+private static ResponseEntity<ValidationApiError> validation(String field, String code) {
+	return ResponseEntity.badRequest()
+		.body(
+			new ValidationApiError(
+				"validation_failed", java.util.List.of(new FieldValidationError(field, code))));
+}
+
 record ApiError(String message) {}
 
 record CodedApiError(String code, String message) {}

backend/src/test/java/fr/nessar/lmnporganizer/rental/adapter/in/web/RentalWebAdaptersTest.java

@@ -2,6 +2,7 @@ package fr.nessar.lmnporganizer.rental.adapter.in.web;
 
 import static org.hamcrest.Matchers.containsInAnyOrder;
 import static org.mockito.ArgumentMatchers.any;
+import static org.mockito.ArgumentMatchers.anyString;
 import static org.mockito.ArgumentMatchers.eq;
 import static org.mockito.Mockito.doThrow;
 import static org.mockito.Mockito.never;
@@ -31,6 +32,7 @@ import fr.nessar.lmnporganizer.rental.application.apartment.ApartmentCatalogServ
 import fr.nessar.lmnporganizer.rental.application.landlord.LandlordAccountService;
 import fr.nessar.lmnporganizer.rental.application.lease.AmendLeaseService;
 import fr.nessar.lmnporganizer.rental.application.lease.GenerateLeaseDocumentService;
+import fr.nessar.lmnporganizer.rental.application.lease.LeaseClauseCatalog;
 import fr.nessar.lmnporganizer.rental.application.lease.LeaseDraftService;
 import fr.nessar.lmnporganizer.rental.application.rent.AllocateRentPaymentService;
 import fr.nessar.lmnporganizer.rental.application.rent.GeneratePaymentReceiptService;
@@ -126,6 +128,7 @@ private static final RentPaymentRefundId REFUND_ID = new RentPaymentRefundId("re
 @MockitoBean private LeaseDraftService leaseDrafts;
 @MockitoBean private AmendLeaseService amendments;
 @MockitoBean private GenerateLeaseDocumentService leaseDocuments;
+@MockitoBean private LeaseClauseCatalog leaseClauseCatalog;
 @MockitoBean private RentPaymentHistoryService paymentHistory;
 @MockitoBean private RecordRentPaymentService paymentRecording;
 @MockitoBean private AllocateRentPaymentService paymentAllocation;
@@ -136,9 +139,17 @@ private static final RentPaymentRefundId REFUND_ID = new RentPaymentRefundId("re
 
 @BeforeEach
 void authenticateLandlordAndFixTime() {
+	Instant now = Instant.parse("2026-03-01T12:00:00Z");
 	when(accounts.identify(any())).thenReturn(landlord());
-	when(clock.instant()).thenReturn(Instant.parse("2026-03-01T12:00:00Z"));
+	when(clock.instant()).thenReturn(now);
 	when(clock.getZone()).thenReturn(ZoneOffset.UTC);
+	when(clock.withZone(any())).thenReturn(Clock.fixed(now, ZoneOffset.UTC));
+	LeaseClauseCatalog clauses =
+		LeaseClauseCatalog.load(getClass().getResourceAsStream("/lease-clauses.yml"));
+	when(leaseClauseCatalog.available(anyString(), any()))
+		.thenAnswer(
+			invocation ->
+				clauses.available(invocation.getArgument(0), invocation.getArgument(1)));
 }
 
 @Test
@@ -161,6 +172,25 @@ void protectedRentalMutationsRejectMissingCsrfTokens() throws Exception {
 		.andExpect(status().isForbidden());
 }
 
+@Test
+void malformedJsonIsAStableClientValidationFailure() throws Exception {
+	mockMvc
+		.perform(
+			post("/api/apartments")
+				.with(asLandlord())
+				.with(csrf())
+				.contentType(MediaType.APPLICATION_JSON)
+				.content(
+					"""
+					{"name":"Studio","address":"12 rue A","purchasePrice":"not-a-number",
+					"description":"","privateAreas":[]}
+					"""))
+		.andExpect(status().isBadRequest())
+		.andExpect(jsonPath("$.code").value("validation_failed"))
+		.andExpect(jsonPath("$.errors[0].field").value("request"))
+		.andExpect(jsonPath("$.errors[0].code").value("malformed"));
+}
+
 @Test
 void oidcClaimsScopeApartmentCreationAndLookupAndResponsesAreMapped() throws Exception {
 	Apartment apartment =
@@ -413,7 +443,11 @@ void leaseDraftRequestsRejectAnImpossibleAnnualRevisionDay() throws Exception {
 																	"referenceYear":2026,"seriesId":"001515333"}}}
 																"""))
 		.andExpect(status().isBadRequest())
-		.andExpect(jsonPath("$.message").value("Le jour annuel de révision IRL est invalide."));
+		.andExpect(jsonPath("$.code").value("validation_failed"))
+		.andExpect(
+			jsonPath("$.errors[0].field")
+				.value("legalTerms.rentRevision.annualRevisionDay"))
+		.andExpect(jsonPath("$.errors[0].code").value("invalid_date"));
 }
 
 @Test

backend/src/test/java/fr/nessar/lmnporganizer/rental/adapter/in/web/lease/LeaseAmendmentWebTest.java

@@ -16,6 +16,7 @@ import fr.nessar.lmnporganizer.rental.adapter.in.web.common.RentalApiExceptionHa
 import fr.nessar.lmnporganizer.rental.application.landlord.LandlordAccountService;
 import fr.nessar.lmnporganizer.rental.application.lease.AmendLeaseService;
 import fr.nessar.lmnporganizer.rental.application.lease.GenerateLeaseDocumentService;
+import fr.nessar.lmnporganizer.rental.application.lease.LeaseClauseCatalog;
 import fr.nessar.lmnporganizer.rental.application.lease.LeaseDraftService;
 import fr.nessar.lmnporganizer.rental.domain.landlord.ExternalIdentity;
 import fr.nessar.lmnporganizer.rental.domain.landlord.Landlord;
@@ -43,6 +44,7 @@ class LeaseAmendmentWebTest {
 @MockitoBean LeaseDraftService drafts;
 @MockitoBean AmendLeaseService amendments;
 @MockitoBean GenerateLeaseDocumentService documents;
+@MockitoBean LeaseClauseCatalog clauseCatalog;
 @MockitoBean Clock clock;
 
 @BeforeEach

frontend/src/app/components/lease-clause-editor/lease-clause-editor.ts

@@ -131,7 +131,7 @@ export class LeaseClauseEditor {
 		this.emit(
 			selected ? [...clauses, { catalogId: id, parameters: {}, customText: '' }] : clauses,
 		);
-		this.fieldChanged.emit('specialClauses[' + index + '].catalogId');
+		this.fieldChanged.emit(selected ? 'specialClauses[' + index + '].catalogId' : 'specialClauses[');
 	}
 
 	parameterValue(catalogId: string, parameterName: string): string {
@@ -178,6 +178,7 @@ export class LeaseClauseEditor {
 
 	removeClause(index: number): void {
 		this.emit(this.specialClauses().filter((_, clauseIndex) => clauseIndex !== index));
+		this.fieldChanged.emit('specialClauses[');
 	}
 
 	private load(): void {

frontend/src/app/components/lease-end-notice-card/lease-end-notice-card.spec.ts

@@ -110,4 +110,23 @@ describe('LeaseEndNoticeCard', () => {
 		});
 		expect(downloadEvidence).toHaveBeenCalledWith('lease-1', 'notice-1', 1, 'preuve.jpg');
 	});
+
+	it('clears a stale evidence error when its file or reason is corrected', () => {
+		const fixture = createFixture();
+		const input = document.createElement('input');
+		const evidence = new File(['new'], 'preuve.txt', { type: 'text/plain' });
+		Object.defineProperty(input, 'files', { value: { item: () => evidence } });
+		fixture.componentInstance.evidenceError.set('Sélectionnez une preuve à conserver.');
+
+		fixture.componentInstance.selectEvidence({ target: input } as unknown as Event);
+
+		expect(fixture.componentInstance.evidenceError()).toBe('');
+		fixture.componentInstance.evidenceError.set(
+			'Indiquez la raison de cette nouvelle version de preuve.',
+		);
+		const reason = document.createElement('input');
+		reason.value = 'Version lisible';
+		fixture.componentInstance.updateEvidenceReason({ target: reason } as unknown as Event);
+		expect(fixture.componentInstance.evidenceError()).toBe('');
+	});
 });

frontend/src/app/components/lease-end-notice-card/lease-end-notice-card.ts

@@ -114,12 +114,14 @@ export class LeaseEndNoticeCard {
 		this.evidence.set(
 			input instanceof HTMLInputElement ? (input.files?.item(0) ?? null) : null,
 		);
+		this.evidenceError.set('');
 		if (input instanceof HTMLInputElement) input.value = '';
 	}
 
 	updateEvidenceReason(event: Event): void {
 		const input = event.target;
 		this.evidenceReason.set(input instanceof HTMLInputElement ? input.value : '');
+		this.evidenceError.set('');
 	}
 
 	submitWithdrawal(): void {

frontend/src/app/components/lease-form/lease-form.ts

@@ -202,6 +202,7 @@ export class LeaseForm {
 		this.guarantors.update((guarantors) =>
 			guarantors.filter((_, itemIndex) => itemIndex !== index),
 		);
+		this.fieldWasChanged('guarantors[');
 	}
 
 	updateGuarantor(index: number, guarantor: Guarantor): void {

frontend/src/app/components/private-area-editor/private-area-editor.spec.ts

@@ -103,6 +103,8 @@ describe('PrivateAreaEditor', () => {
 		]);
 		const changed = vi.fn();
 		fixture.componentInstance.areasChanged.subscribe(changed);
+		const fieldChanged = vi.fn();
+		fixture.componentInstance.fieldChanged.subscribe(fieldChanged);
 		const family = document.createElement('select');
 		family.append(new Option('Annexe', 'ANNEXE'));
 		family.value = 'ANNEXE';
@@ -122,5 +124,6 @@ describe('PrivateAreaEditor', () => {
 		);
 		expect(changed.mock.calls[1][0][0]).toEqual(expect.objectContaining({ label: 'Cave' }));
 		expect(changed.mock.calls[2][0]).toEqual([]);
+		expect(fieldChanged).toHaveBeenCalledWith('privateAreas[');
 	});
 });

frontend/src/app/components/private-area-editor/private-area-editor.ts

@@ -104,6 +104,7 @@ export class PrivateAreaEditor {
 
 	removeArea(id: string): void {
 		this.areasChanged.emit(this.areas().filter((area) => area.id !== id));
+		this.fieldChanged.emit('privateAreas[');
 	}
 
 	validate(): boolean {

frontend/src/app/services/workspace-resource.ts

@@ -108,8 +108,10 @@ export class WorkspaceResource<T extends { id?: string }> {
 
 	clearSaveFieldError(key: string, field: string): void {
 		const fieldErrors = this.saveFieldErrors()[key];
-		if (!fieldErrors?.some((error) => error.field === field)) return;
+		const matches = (candidate: string) =>
-		const remaining = fieldErrors.filter((error) => error.field !== field);
+			field.endsWith('[') ? candidate.startsWith(field) : candidate === field;
+		if (!fieldErrors?.some((error) => matches(error.field))) return;
+		const remaining = fieldErrors.filter((error) => !matches(error.field));
 		this.saveFieldErrors.update((errors) =>
 			remaining.length ? { ...errors, [key]: remaining } : withoutRecordKey(errors, key),
 		);

frontend/src/app/services/workspace.service.spec.ts

@@ -328,6 +328,30 @@ describe('WorkspaceService', () => {
 		);
 	});
 
+	it('clears indexed apartment errors after a structural collection change', () => {
+		apartments.updateApartment.mockReturnValueOnce(
+			throwError(() => ({
+				status: 400,
+				error: {
+					code: 'validation_failed',
+					errors: [
+						{ field: 'privateAreas[0].label', code: 'not_blank' },
+						{ field: 'privateAreas[1].family', code: 'not_null' },
+						{ field: 'name', code: 'not_blank' },
+					],
+				},
+			})),
+		);
+		const service = TestBed.inject(WorkspaceService);
+		service.saveApartment(apartment, apartment.id);
+
+		service.clearApartmentSaveFieldError('privateAreas[', apartment.id);
+
+		expect(service.apartmentSaveFieldErrors(apartment.id)).toEqual([
+			{ field: 'name', code: 'not_blank' },
+		]);
+	});
+
 	it('removes a confirmed deletion locally before reconciliation finishes', () => {
 		const deleteResponse = new Subject<void>();
 		const refreshResponse = new Subject<(typeof apartment)[]>();
@@ -529,12 +553,14 @@ describe('WorkspaceService', () => {
 			throwError(() => ({ error: { message: 'Format refusé' } })),
 		);
 		service.uploadTenantAttachment('tenant-1', new File(['id'], 'id.pdf'));
-		expect(service.tenantAttachmentErrors()['tenant-1']).toBe('Format refusé');
+		expect(service.tenantAttachmentErrors()['tenant-1']).toBe(
+			'Impossible d’envoyer cette pièce jointe. Vérifiez le fichier et sa taille maximale.',
+		);
 
 		tenants.uploadAttachment.mockReturnValueOnce(throwError(() => new Error('offline')));
 		service.uploadTenantAttachment('tenant-1', new File(['id'], 'id.pdf'));
 		expect(service.tenantAttachmentErrors()['tenant-1']).toBe(
-			'Impossible d’envoyer cette pièce jointe.',
+			'Impossible d’envoyer cette pièce jointe. Vérifiez le fichier et sa taille maximale.',
 		);
 	});