Handling Multi-Tenant Authorization in PHP

Scope every query to the authenticated tenant and verify access at the resource boundary.

The objective is to understand the behavior and operational limits, not only the method name.

What It Does

Scope every query to the authenticated tenant and verify access at the resource boundary.

Prerequisites

Use a dedicated development environment and sample data. Where a snippet uses an injected connection, repository, request value or mailer, supply it from your own application setup.

Example 1: Basic Use

A focused working pattern for this topic. Names such as $pdo, $authContext and $repo represent dependencies provided by the application unless initialized in the snippet.

<?php
$tenantId = $authContext->tenantId();
$stmt = $pdo->prepare('SELECT id, title FROM documents WHERE tenant_id = :tenant AND id = :id');
$stmt->execute(['tenant' => $tenantId, 'id' => $documentId]);
$document = $stmt->fetch(PDO::FETCH_ASSOC);
if (!$document) { http_response_code(404); exit; }

Example 2: A Second Scenario

A second use case that adds a different operation or data flow specific to this topic.

<?php
$tenant = $authContext->tenantId();
$stmt = $pdo->prepare('UPDATE invoices SET status=? WHERE tenant_id=? AND id=?');
$stmt->execute(['paid',$tenant,$invoiceId]);
if ($stmt->rowCount() !== 1) { http_response_code(404); exit; }

Example 3: Practical Checks

A practical validation, failure or deployment concern specific to this topic.

<?php
$tenant = $authContext->tenantId();
$stmt = $pdo->prepare('SELECT id,name FROM customers WHERE tenant_id=? ORDER BY id LIMIT 50');
$stmt->execute([$tenant]);
$customers = $stmt->fetchAll(PDO::FETCH_ASSOC);

Important Behavior and Edge Cases

Never trust a tenant ID supplied by the client; derive tenant context from an authenticated server-side claim.

For production use, also account for error handling, data validation, resource limits and environment-specific driver behavior.

Comparison with Related Approaches

Common Beginner Mistakes

Key Takeaways

• Scope every query to the authenticated tenant and verify access at the resource boundary.
• Never trust a tenant ID supplied by the client; derive tenant context from an authenticated server-side claim.
• Use this workflow as a focused starting point rather than a substitute for application-level tests.

Choose this API or pattern when its exact semantics match your task, and verify the result against the database driver and runtime used by your application.