fix #557: guide permission-driven VPD flow

src/main/java/com/cloudhandson/vpdbackoffice/web/VpdPolicyController.java

@@ -4,6 +4,8 @@ import com.cloudhandson.vpdbackoffice.domain.vpd.VpdPolicyCreateCommand;
 import com.cloudhandson.vpdbackoffice.service.AppException;
 import com.cloudhandson.vpdbackoffice.service.VpdPolicyService;
 import java.util.List;
+import java.util.LinkedHashMap;
+import java.util.Map;
 import org.springframework.dao.DataAccessException;
 import org.springframework.stereotype.Controller;
 import org.springframework.ui.Model;
@@ -42,10 +44,34 @@ public class VpdPolicyController {
   private void populatePolicyModel(String schemaOwner, Model model) {
     try {
       String selectedSchemaOwner = schemaOwner == null ? "" : schemaOwner.trim().toUpperCase();
-      model.addAttribute("policies", vpdPolicyService.findPolicies());
+      List<com.cloudhandson.vpdbackoffice.domain.vpd.VpdPolicyView> policies = vpdPolicyService.findPolicies();
+      Map<String, String> policyDescriptions = new LinkedHashMap<>();
+      policies.forEach(policy -> policyDescriptions.put(
+          policy.objectDisplayName() + "|" + policy.policyName(),
+          vpdPolicyService.findPolicyDescription(policy.objectOwner(), policy.objectName(), policy.policyName())
+      ));
+      model.addAttribute("policies", policies);
+      model.addAttribute("policyDescriptions", policyDescriptions);
       model.addAttribute("vpdTargets", vpdPolicyService.findVpdTargets(selectedSchemaOwner));
       model.addAttribute("selectedSchemaOwner", selectedSchemaOwner);
-      model.addAttribute("formOptions", vpdPolicyService.formOptions());
+      var formOptions = vpdPolicyService.formOptions();
+      Map<String, String> filterDescriptions = new LinkedHashMap<>();
+      formOptions.functions().forEach(function -> filterDescriptions.put(
+          function.owner() + "|" + function.functionName(),
+          vpdPolicyService.findFilterDescription(function.owner(), function.functionName())
+      ));
+      policies.forEach(policy -> filterDescriptions.putIfAbsent(
+          policy.functionOwner() + "|" + policy.functionName(),
+          vpdPolicyService.findFilterDescription(policy.functionOwner(), policy.functionName())
+      ));
+      Map<String, String> filterPredicates = new LinkedHashMap<>();
+      formOptions.functions().forEach(function -> filterPredicates.put(
+          function.owner() + "|" + function.functionName(),
+          vpdPolicyService.findFilterPredicate(function.owner(), function.packageName(), function.functionName())
+      ));
+      model.addAttribute("formOptions", formOptions);
+      model.addAttribute("filterDescriptions", filterDescriptions);
+      model.addAttribute("filterPredicates", filterPredicates);
     } catch (DataAccessException exception) {
       RuntimeErrorMessage message = RuntimeErrorMessages.dataAccess(exception);
       model.addAttribute("runtimeError", message);
@@ -53,12 +79,18 @@ public class VpdPolicyController {
       model.addAttribute("vpdTargets", List.of());
       model.addAttribute("selectedSchemaOwner", "");
       model.addAttribute("formOptions", vpdPolicyService.emptyFormOptions());
+      model.addAttribute("policyDescriptions", Map.of());
+      model.addAttribute("filterDescriptions", Map.of());
+      model.addAttribute("filterPredicates", Map.of());
     } catch (AppException exception) {
       model.addAttribute("errorMessage", exception.getMessage());
       model.addAttribute("policies", List.of());
       model.addAttribute("vpdTargets", List.of());
       model.addAttribute("selectedSchemaOwner", "");
       model.addAttribute("formOptions", vpdPolicyService.emptyFormOptions());
+      model.addAttribute("policyDescriptions", Map.of());
+      model.addAttribute("filterDescriptions", Map.of());
+      model.addAttribute("filterPredicates", Map.of());
     }
   }
 
@@ -105,10 +137,18 @@ public class VpdPolicyController {
       @RequestParam(required = false) String functionOwner,
       @RequestParam String functionName,
       @RequestParam String filterPredicate,
+      @RequestParam(defaultValue = "Filter function이 반환하는 predicate로 조회 행을 제한합니다.") String description,
       RedirectAttributes redirectAttributes
   ) {
     try {
       vpdPolicyService.saveFilterFunction(functionOwner, functionName, filterPredicate);
+      vpdPolicyService.saveFilterDescription(
+          functionOwner == null || functionOwner.isBlank()
+              ? vpdPolicyService.currentUser()
+              : functionOwner,
+          functionName,
+          description
+      );
       redirectAttributes.addFlashAttribute("successMessage", "Filter function을 저장했습니다: " + functionName);
     } catch (AppException exception) {
       redirectAttributes.addFlashAttribute("errorMessage", exception.getMessage());
@@ -119,6 +159,23 @@ public class VpdPolicyController {
     return "redirect:/vpd-filter-policies";
   }
 
+  @PostMapping("/vpd-policies/description")
+  public String savePolicyDescription(
+      @RequestParam String objectOwner,
+      @RequestParam String objectName,
+      @RequestParam String policyName,
+      @RequestParam String description,
+      RedirectAttributes redirectAttributes
+  ) {
+    try {
+      vpdPolicyService.savePolicyDescription(objectOwner, objectName, policyName, description);
+      redirectAttributes.addFlashAttribute("successMessage", "Policy 설명을 저장했습니다.");
+    } catch (AppException exception) {
+      redirectAttributes.addFlashAttribute("errorMessage", exception.getMessage());
+    }
+    return "redirect:/vpd-policies";
+  }
+
   @PostMapping("/vpd-filter-policies/replace")
   public String replaceFilterPolicy(
       @RequestParam String oldObjectKey,