Protect Your Application from Sharing Violations

When using Apex, ensure that you don’t inadvertently expose sensitive data. Apex generally runs in system context, which grants it access to all objects and fields without applying object permissions, field-level security, or sharing rules for the current user. Usually, system context provides the correct behavior for operations, such as triggers, that need access to all data in a Salesforce org. However, you can also specify that certain Apex classes must enforce the sharing rules that apply to the current user.

There are three keywords to remember for sharing rules.

• With sharing: Use this to enforce the current user's sharing rules for a class. Here's sample code.
  1public with sharing class ProjectService {
  2    public static List<Project__c> getProjects() {
  3        // This query respects sharing rules for Project__c
  4        return [SELECT Id, Name, Status__c FROM Project__c];
  5    }
  6}
  7

• Without sharing: Use this to ensure the current user's sharing rules are not enforced for a class. Here's sample code.
  1public without sharing class ProjectServiceWithoutSharing {
  2    public static List<Project__c> getProjects() {
  3        // This query ignores sharing rules for Project__c
  4        return [SELECT Id, Name, Status__c FROM Project__c];
  5    }
  6}
  7

• Inherited sharing: Use this to run an Apex class in the same sharing mode as the class that called it. Inherited sharing clarifies intent and avoids ambiguity that can arise from an omitted sharing declaration, helping ensure privileged Apex code isn't used insecurely.
  1public inherited sharing class ProjectServiceInheritedSharing {
  2    public static List<Project__c> getProjects() {
  3        // Sharing mode depends on caller context
  4        return [SELECT Id, Name, Status__c FROM Project__c];
  5    }
  6}
  7

Enforcing the current user's sharing rules can impact the following.

• SOQL and SOSL queries: Queries can sometimes return fewer rows than they would in system context.
• Data Manipulation Language (DML) operations: Operations might fail if the current user lacks the necessary permissions. For example, if a user specifies a foreign key value that they don’t have access to.