Add record access strategy

backend/src/object/models/model.service.ts

@@ -0,0 +1,184 @@
+import { Injectable, Logger } from '@nestjs/common';
+import { Knex } from 'knex';
+import { ModelClass } from 'objection';
+import { BaseModel } from './base.model';
+import { ModelRegistry } from './model.registry';
+import { ObjectMetadata } from './dynamic-model.factory';
+import { TenantDatabaseService } from '../../tenant/tenant-database.service';
+import { UserModel, RoleModel, PermissionModel } from './system-models';
+
+/**
+ * Service to manage dynamic models for a specific tenant
+ */
+@Injectable()
+export class ModelService {
+  private readonly logger = new Logger(ModelService.name);
+  private tenantRegistries = new Map<string, ModelRegistry>();
+
+  constructor(private tenantDbService: TenantDatabaseService) {}
+
+  /**
+   * Get or create a registry for a tenant
+   */
+  getTenantRegistry(tenantId: string): ModelRegistry {
+    if (!this.tenantRegistries.has(tenantId)) {
+      const registry = new ModelRegistry();
+      
+      // Register system models that are defined as static Objection models
+      this.registerSystemModels(registry);
+      
+      this.tenantRegistries.set(tenantId, registry);
+    }
+    return this.tenantRegistries.get(tenantId)!;
+  }
+
+  /**
+   * Register static system models in the registry
+   * Uses simplified models without complex relationMappings to avoid modelPath issues
+   */
+  private registerSystemModels(registry: ModelRegistry): void {
+    // Register system models by their API name (used in referenceObject fields)
+    // These are simplified versions without relationMappings to avoid dependency issues
+    registry.registerModel('User', UserModel as any);
+    registry.registerModel('Role', RoleModel as any);
+    registry.registerModel('Permission', PermissionModel as any);
+    
+    this.logger.debug('Registered system models: User, Role, Permission');
+  }
+
+  /**
+   * Create and register a model for a tenant
+   */
+  async createModelForObject(
+    tenantId: string,
+    objectMetadata: ObjectMetadata,
+  ): Promise<ModelClass<BaseModel>> {
+    const registry = this.getTenantRegistry(tenantId);
+    const model = registry.createAndRegisterModel(objectMetadata);
+
+    this.logger.log(
+      `Registered model for ${objectMetadata.apiName} in tenant ${tenantId}`,
+    );
+
+    return model;
+  }
+
+  /**
+   * Get a model for a tenant and object
+   */
+  getModel(tenantId: string, objectApiName: string): ModelClass<BaseModel> {
+    const registry = this.getTenantRegistry(tenantId);
+    return registry.getModel(objectApiName);
+  }
+
+  /**
+   * Get a bound model (with knex connection) for a tenant and object
+   */
+  async getBoundModel(
+    tenantId: string,
+    objectApiName: string,
+  ): Promise<ModelClass<BaseModel>> {
+    const knex = await this.tenantDbService.getTenantKnexById(tenantId);
+    const model = this.getModel(tenantId, objectApiName);
+    
+    // Bind knex to the model and also to all models in the registry
+    // This ensures system models also have knex bound when they're used in relations
+    const registry = this.getTenantRegistry(tenantId);
+    const allModels = registry.getAllModelNames();
+    
+    // Bind knex to all models to ensure relations work
+    for (const modelName of allModels) {
+      try {
+        const m = registry.getModel(modelName);
+        if (m && !m.knex()) {
+          m.knex(knex);
+        }
+      } catch (error) {
+        // Ignore errors for models that don't need binding
+      }
+    }
+    
+    return model.bindKnex(knex);
+  }
+
+  /**
+   * Check if a model exists for a tenant
+   */
+  hasModel(tenantId: string, objectApiName: string): boolean {
+    const registry = this.getTenantRegistry(tenantId);
+    return registry.hasModel(objectApiName);
+  }
+
+  /**
+   * Get all model names for a tenant
+   */
+  getAllModelNames(tenantId: string): string[] {
+    const registry = this.getTenantRegistry(tenantId);
+    return registry.getAllModelNames();
+  }
+
+  /**
+   * Ensure a model is registered with all its dependencies.
+   * This method handles recursive model creation for related objects.
+   * 
+   * @param tenantId - The tenant ID
+   * @param objectApiName - The object API name to ensure registration for
+   * @param fetchMetadata - Callback function to fetch object metadata (provided by ObjectService)
+   * @param visited - Set to track visited models and prevent infinite loops
+   */
+  async ensureModelWithDependencies(
+    tenantId: string,
+    objectApiName: string,
+    fetchMetadata: (apiName: string) => Promise<ObjectMetadata>,
+    visited: Set<string> = new Set(),
+  ): Promise<void> {
+    // Prevent infinite recursion
+    if (visited.has(objectApiName)) {
+      return;
+    }
+    visited.add(objectApiName);
+
+    // Check if model already exists
+    if (this.hasModel(tenantId, objectApiName)) {
+      return;
+    }
+
+    try {
+      // Fetch the object metadata
+      const objectMetadata = await fetchMetadata(objectApiName);
+
+      // Extract lookup fields to find dependencies
+      const lookupFields = objectMetadata.fields.filter(
+        f => f.type === 'LOOKUP' && f.referenceObject
+      );
+
+      // Recursively ensure all dependent models are registered first
+      for (const field of lookupFields) {
+        if (field.referenceObject) {
+          try {
+            await this.ensureModelWithDependencies(
+              tenantId,
+              field.referenceObject,
+              fetchMetadata,
+              visited,
+            );
+          } catch (error) {
+            // If related object doesn't exist (e.g., system tables), skip it
+            this.logger.debug(
+              `Skipping registration of related model ${field.referenceObject}: ${error.message}`
+            );
+          }
+        }
+      }
+
+      // Now create and register this model (all dependencies are ready)
+      await this.createModelForObject(tenantId, objectMetadata);
+      this.logger.log(`Registered model for ${objectApiName} in tenant ${tenantId}`);
+    } catch (error) {
+      this.logger.warn(
+        `Failed to ensure model for ${objectApiName}: ${error.message}`
+      );
+      throw error;
+    }
+  }
+}