# Implementation Plan: Tenant RBAC v1

**Branch**: `062-tenant-rbac-v1` | **Date**: 2026-01-25 | **Spec**: [specs/062-tenant-rbac-v1/spec.md](specs/062-tenant-rbac-v1/spec.md)
**Input**: Feature specification from `specs/062-tenant-rbac-v1/spec.md`

## Summary

This feature introduces a comprehensive Role-Based Access Control (RBAC) system for TenantAtlas. It leverages Microsoft Entra ID for authentication and manages authorization on a per-Suite-Tenant basis. The core of this feature is the `tenant_memberships` table, which will be the source of truth for authorization. The implementation will follow a capabilities-first approach, where permissions are checked using Gates and Policies rather than direct role comparisons.

### Clarifications
- No Entra user credentials are stored; only the dedicated break-glass platform superadmin may have local credentials.
- All access control decisions must be auditable.
- Non-member access to tenant-scoped routes (including direct `/t/{tenant}` URLs) MUST be deny-as-not-found (404).
- A canonical capability registry (e.g., `app/Support/Auth/Capabilities.php` or an enum) will be the source of truth. Role → capability mapping MUST reference only registry entries; tests must fail if unknown capabilities are used.
- Audit action_ids will be standardized:
    - `tenant_membership.add`
    - `tenant_membership.role_change`
    - `tenant_membership.remove`
    - `tenant_membership.bootstrap_assign`
    - `tenant_membership.bootstrap_recover`
    - `tenant_role_mapping.create`
    - `tenant_role_mapping.update`
    - `tenant_role_mapping.delete`
- The system MUST prevent removing or demoting the last remaining `owner` membership for a Suite Tenant.

## Technical Context

**Language/Version**: PHP 8.4
**Primary Dependencies**: Laravel 12, Filament v5, Livewire v4
**Storage**: PostgreSQL
**Testing**: Pest
**Target Platform**: Web
**Project Type**: Web Application
**Performance Goals**:
-   User login and tenant selection should be completed in under 3 seconds.
-   Membership changes should be reflected in under 2 seconds.
-   Audit log entries should be created in under 1 second.
**Constraints**:
-   No Entra user credentials are stored; only the dedicated break-glass platform superadmin may have local credentials.
-   All access control decisions must be auditable.
**Scale/Scope**:
-   The system should be designed to handle up to 1,000 tenants and 10,000 users.

## Constitution Check

*GATE: Must pass before Phase 0 research. Re-check after Phase 1 design.*

-   **Inventory-first**: Not directly applicable.
-   **Read/write separation**: **PASS**.
-   **Graph contract path**: **PASS**.
-   **Deterministic capabilities**: **PASS**.
-   **Tenant isolation**: **PASS**.
-   **Run observability**: **PASS**.
-   **Automation**: **PASS**.
-   **Data minimization**: **PASS**.
-   **Badge semantics (BADGE-001)**: Not applicable.

## Project Structure

### Documentation (this feature)

```text
specs/062-tenant-rbac-v1/
├── plan.md              # This file
├── research.md          # Phase 0 output
├── data-model.md        # Phase 1 output
├── quickstart.md        # Phase 1 output
├── contracts/           # Phase 1 output
└── tasks.md             # Phase 2 output
```

### Source Code (repository root)

```text
app/
├── Models/
│   ├── User.php
│   ├── Tenant.php
│   ├── TenantMembership.php
│   └── TenantRoleMapping.php
├── Policies/
│   └── TenantMembershipPolicy.php
├── Providers/
│   └── AuthServiceProvider.php
└── Support/
    └── Auth/
        └── Capabilities.php
database/
└── migrations/
    ├── XXXX_XX_XX_XXXXXX_create_tenant_memberships_table.php
    └── XXXX_XX_XX_XXXXXX_create_tenant_role_mappings_table.php
routes/
└── web.php
tests/
└── Feature/
    └── TenantRBAC.php
```

**Structure Decision**: The project is a standard Laravel application. New files will be created in the appropriate directories.

## Complexity Tracking

No violations to the constitution.