orion/docs/implementation/inventory-admin-migration.md

Admin Inventory Management Migration Plan

Overview

Objective: Add inventory management capabilities to the admin "Vendor Operations" section, allowing administrators to view and manage vendor inventory on their behalf.

Status: Phase 1 Complete

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Current State Analysis

What Exists

The inventory system is fully implemented at the vendor API level with comprehensive functionality:

Component	Status	Location
Database Model	✅ Complete	models/database/inventory.py
Pydantic Schemas	✅ Complete	models/schema/inventory.py
Service Layer	✅ Complete	app/services/inventory_service.py
Vendor API	✅ Complete	app/api/v1/vendor/inventory.py
Exceptions	✅ Complete	app/exceptions/inventory.py
Unit Tests	✅ Complete	tests/unit/services/test_inventory_service.py
Integration Tests	✅ Complete	tests/integration/api/v1/vendor/test_inventory.py
Vendor UI	🔲 Placeholder	app/templates/vendor/inventory.html
Admin API	🔲 Not Started	-
Admin UI	🔲 Not Started	-
Audit Trail	🔲 Not Started	Logs only, no dedicated table

Storage/Location Architecture

The inventory system tracks stock at the storage location level:

Product A
├── WAREHOUSE_MAIN: 100 units (10 reserved)
├── WAREHOUSE_WEST: 50 units (0 reserved)
└── STORE_FRONT: 25 units (5 reserved)

Total: 175 units | Reserved: 15 | Available: 160

Key design decisions:

• One product can have inventory across multiple locations
• Unique constraint: (product_id, location) - one entry per product/location
• Locations are text strings, normalized to UPPERCASE
• Available quantity = quantity - reserved_quantity

Existing Operations

Operation	Description	Service Method
Set	Replace exact quantity at location	set_inventory()
Adjust	Add/remove quantity (positive/negative)	adjust_inventory()
Reserve	Mark items for pending order	reserve_inventory()
Release	Cancel reservation	release_reservation()
Fulfill	Complete order (reduces both qty & reserved)	fulfill_reservation()
Get Product	Summary across all locations	get_product_inventory()
Get Vendor	List with filters	get_vendor_inventory()
Update	Partial field update	update_inventory()
Delete	Remove inventory entry	delete_inventory()

Vendor API Endpoints

All endpoints at /api/v1/vendor/inventory/*:

Method	Endpoint	Operation
POST	/inventory/set	Set exact quantity
POST	/inventory/adjust	Add/remove quantity
POST	/inventory/reserve	Reserve for order
POST	/inventory/release	Cancel reservation
POST	/inventory/fulfill	Complete order
GET	/inventory/product/{id}	Product summary
GET	/inventory	List with filters
PUT	/inventory/{id}	Update entry
DELETE	/inventory/{id}	Delete entry

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Gap Analysis

What's Missing for Admin Vendor Operations

1. Admin API Endpoints - ✅ Implemented in Phase 1
2. Admin UI Page - No inventory management interface in admin panel
3. Vendor Selector - Admin needs to select which vendor to manage
4. Cross-Vendor View - ✅ Implemented in Phase 1
5. Audit Trail - Only application logs, no queryable audit history
6. Bulk Operations - No bulk adjust/import capabilities
7. Low Stock Alerts - Basic filter exists, no alert configuration

Digital Products - Infinite Inventory ✅

Implementation Complete

Digital products now have unlimited inventory by default:

# In Product model (models/database/product.py)
UNLIMITED_INVENTORY = 999999

@property
def has_unlimited_inventory(self) -> bool:
    """Digital products have unlimited inventory."""
    return self.is_digital

@property
def available_inventory(self) -> int:
    """Calculate available inventory (total - reserved).

    Digital products return unlimited inventory.
    """
    if self.has_unlimited_inventory:
        return self.UNLIMITED_INVENTORY
    return sum(inv.available_quantity for inv in self.inventory_entries)

Behavior:

• Physical products: Sum of inventory entries (0 if no entries)
• Digital products: Returns 999999 (unlimited) regardless of entries
• Orders for digital products never fail due to "insufficient inventory"

Tests: tests/unit/models/database/test_product.py::TestProductInventoryProperties

Documentation: Inventory Management Guide

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Migration Plan

Phase 1: Admin API Endpoints

Goal: Expose inventory management to admin users with vendor selection

1.1 New File: app/api/v1/admin/inventory.py

Admin endpoints that mirror vendor functionality with vendor_id as parameter:

Method	Endpoint	Description
GET	/admin/inventory	List all inventory (cross-vendor)
GET	/admin/inventory/vendors/{vendor_id}	Vendor-specific inventory
GET	/admin/inventory/products/{product_id}	Product inventory summary
POST	/admin/inventory/set	Set inventory (requires vendor_id)
POST	/admin/inventory/adjust	Adjust inventory
PUT	/admin/inventory/{id}	Update inventory entry
DELETE	/admin/inventory/{id}	Delete inventory entry
GET	/admin/inventory/low-stock	Low stock report

1.2 Schema Extensions

Add admin-specific request schemas in models/schema/inventory.py:

class AdminInventoryCreate(InventoryCreate):
    """Admin version - requires explicit vendor_id."""
    vendor_id: int = Field(..., description="Target vendor ID")

class AdminInventoryAdjust(InventoryAdjust):
    """Admin version - requires explicit vendor_id."""
    vendor_id: int = Field(..., description="Target vendor ID")

class AdminInventoryListResponse(BaseModel):
    """Cross-vendor inventory list."""
    inventories: list[InventoryResponse]
    total: int
    skip: int
    limit: int
    vendor_filter: int | None = None

1.3 Service Layer Reuse

The existing InventoryService already accepts vendor_id as a parameter - no service changes needed. Admin endpoints simply pass the vendor_id from the request instead of from the JWT token.

Phase 2: Admin UI

Goal: Create admin inventory management page

2.1 New Files

File	Description
app/templates/admin/inventory.html	Main inventory page
static/admin/js/inventory.js	Alpine.js controller

2.2 UI Features

1. Vendor Selector Dropdown - Filter by vendor (or show all)
2. Inventory Table - Product, Location, Quantity, Reserved, Available
3. Search/Filter - By product name, location, low stock
4. Adjust Modal - Quick add/remove with reason
5. Pagination - Handle large inventories
6. Export - CSV download (future)

2.3 Page Layout

┌─────────────────────────────────────────────────────────┐
│ Inventory Management                    [Vendor: All ▼] │
├─────────────────────────────────────────────────────────┤
│ [Search...] [Location ▼] [Low Stock Only ☐]            │
├─────────────────────────────────────────────────────────┤
│ Product      │ Location    │ Qty │ Reserved │ Available │
│──────────────┼─────────────┼─────┼──────────┼───────────│
│ Widget A     │ WAREHOUSE_A │ 100 │ 10       │ 90   [⚙️] │
│ Widget A     │ WAREHOUSE_B │ 50  │ 0        │ 50   [⚙️] │
│ Gadget B     │ WAREHOUSE_A │ 25  │ 5        │ 20   [⚙️] │
├─────────────────────────────────────────────────────────┤
│ Showing 1-20 of 150                    [< 1 2 3 ... >]  │
└─────────────────────────────────────────────────────────┘

2.4 Sidebar Integration

Add to app/templates/admin/partials/sidebar.html:

<!-- Under Vendor Operations section -->
<li class="relative px-6 py-3">
    <a href="/admin/inventory" ...>
        <span class="inline-flex items-center">
            <!-- inventory icon -->
            <span class="ml-4">Inventory</span>
        </span>
    </a>
</li>

Phase 3: Audit Trail (Optional Enhancement)

Goal: Track inventory changes with queryable history

3.1 Database Migration

CREATE TABLE inventory_audit_log (
    id SERIAL PRIMARY KEY,
    inventory_id INTEGER REFERENCES inventory(id) ON DELETE SET NULL,
    product_id INTEGER NOT NULL,
    vendor_id INTEGER NOT NULL,
    location VARCHAR(255) NOT NULL,

    -- Change details
    operation VARCHAR(50) NOT NULL,  -- 'set', 'adjust', 'reserve', 'release', 'fulfill'
    quantity_before INTEGER,
    quantity_after INTEGER,
    reserved_before INTEGER,
    reserved_after INTEGER,
    adjustment_amount INTEGER,

    -- Context
    reason VARCHAR(500),
    performed_by INTEGER REFERENCES users(id),
    performed_by_type VARCHAR(20) NOT NULL,  -- 'vendor', 'admin', 'system'

    created_at TIMESTAMP DEFAULT NOW()
);

CREATE INDEX idx_audit_vendor ON inventory_audit_log(vendor_id);
CREATE INDEX idx_audit_product ON inventory_audit_log(product_id);
CREATE INDEX idx_audit_created ON inventory_audit_log(created_at);

3.2 Service Enhancement

Add audit logging to InventoryService methods:

def _log_audit(
    self,
    db: Session,
    inventory: Inventory,
    operation: str,
    qty_before: int,
    qty_after: int,
    reserved_before: int,
    reserved_after: int,
    user_id: int | None,
    user_type: str,
    reason: str | None = None
) -> None:
    """Record inventory change in audit log."""
    audit = InventoryAuditLog(
        inventory_id=inventory.id,
        product_id=inventory.product_id,
        vendor_id=inventory.vendor_id,
        location=inventory.location,
        operation=operation,
        quantity_before=qty_before,
        quantity_after=qty_after,
        reserved_before=reserved_before,
        reserved_after=reserved_after,
        adjustment_amount=qty_after - qty_before,
        reason=reason,
        performed_by=user_id,
        performed_by_type=user_type,
    )
    db.add(audit)

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Implementation Checklist

Phase 1: Admin API ✅

• Create app/api/v1/admin/inventory.py
• Add admin inventory schemas to models/schema/inventory.py
• Register routes in app/api/v1/admin/__init__.py
• Write integration tests tests/integration/api/v1/admin/test_inventory.py

Phase 2: Admin UI

• Create app/templates/admin/inventory.html
• Create static/admin/js/inventory.js
• Add route in app/routes/admin.py
• Add sidebar menu item
• Update static/admin/js/init-alpine.js for page mapping

Phase 3: Audit Trail (Optional)

• Create Alembic migration for inventory_audit_log table
• Create models/database/inventory_audit_log.py
• Update InventoryService with audit logging
• Add audit history endpoint
• Add audit history UI component

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Testing Strategy

Unit Tests

• Admin schema validation tests
• Audit log creation tests (if implemented)

Integration Tests

• Admin inventory endpoints with authentication
• Vendor isolation verification (admin can access any vendor)
• Audit trail creation on operations

Manual Testing

• Verify vendor selector works correctly
• Test adjust modal workflow
• Confirm pagination with large datasets

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Rollback Plan

Each phase is independent:

1. Phase 1 Rollback: Remove admin inventory routes from __init__.py
2. Phase 2 Rollback: Remove sidebar link, delete template/JS files
3. Phase 3 Rollback: Run down migration to drop audit table

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Dependencies

• Existing InventoryService (no changes required)
• Admin authentication (get_current_admin_api)
• Vendor model for vendor selector dropdown

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Related Documentation

• Vendor Operations Expansion Plan
• Admin Integration Guide
• Architecture Patterns