NetBox Inventory Monitor Plugin

A comprehensive NetBox plugin for asset management with semi-automatic discovery processes. This plugin extends NetBox with powerful inventory tracking capabilities, including asset lifecycle management, probe monitoring, contract tracking, and RMA (Return Merchandise Authorization) processing.

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Features

• 🏷️ Asset Management: Track physical and logical assets with detailed metadata
• 📊 Probe Monitoring: Visual status indicators for discovery data populated by external scripts (e.g., SNMP scans)
• 📝 Contract Tracking: Manage contracts, contractors, and invoicing with multi-currency support
• 🔄 RMA Processing: Complete RMA workflow with serial number tracking
• 🏢 External Inventory: Integration with external inventory systems with configurable status mappings
• 🛠️ Asset Services: Track maintenance and service contracts with multi-currency pricing
• 📈 Lifecycle Management: Full asset lifecycle status tracking
• 🔍 Advanced Search: Powerful filtering and search capabilities with GraphQL support
• 🎨 Visual Interface: Rich UI with status indicators and color coding
• 🔌 NetBox Integration: Native NetBox plugin following best practices
• 💱 Multi-Currency Support: Configurable currency support for all financial fields (assets, contracts, invoices, services)

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Table of Contents

• Features
• Data Model Overview
• Data Models
• Installation
• Upgrade Guide
• Configuration
• Usage
• Development
• License
• Acknowledgments

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Data Model Overview

classDiagram
    class AssetType {
        +CharField name
        +SlugField slug
        +CharField description
        +ColorField color
    }

    class Asset {
        +CharField serial*
        +CharField partnumber
        +CharField description
        +CharField assignment_status
        +CharField lifecycle_status
        +PositiveIntegerField quantity
        +DecimalField price
        +CharField currency
        +CharField project
        +CharField vendor
        +DateField warranty_start
        +DateField warranty_end
        +GenericForeignKey assigned_object
        +ForeignKey type
        +ForeignKey order_contract
        +TextField comments
        +is_recently_probed()
        +get_related_probes()
        +delete() throws ValidationError
    }

    class AssetService {
        +DateField service_start
        +DateField service_end
        +DecimalField service_price
        +CharField service_currency
        +CharField service_category
        +CharField service_category_vendor
        +ForeignKey asset
        +ForeignKey contract
    }

    class Contract {
        +CharField name
        +CharField name_internal
        +CharField type
        +DecimalField price
        +CharField currency
        +DateField signed
        +DateField accepted
        +DateField invoicing_start
        +DateField invoicing_end
        +TextField comments
        +ForeignKey contractor
        +ForeignKey parent
        +clean() validates price/currency
    }

    class Contractor {
        +CharField name
        +CharField company
        +CharField address
        +ForeignKey tenant
    }

    class Invoice {
        +CharField name
        +CharField project
        +DecimalField price
        +CharField currency
        +DateField invoicing_start
        +DateField invoicing_end
        +ForeignKey contract
    }

    class Probe {
        +DateTimeField time
        +DateTimeField creation_time
        +CharField name
        +CharField serial
        +CharField part
        +CharField category
        +CharField device_descriptor
        +CharField site_descriptor
        +CharField location_descriptor
        +TextField description
        +TextField comments
        +JSONField discovered_data
        +ForeignKey device
        +ForeignKey site
        +ForeignKey location
        +is_recently_probed()
    }

    class RMA {
        +CharField rma_number
        +CharField original_serial
        +CharField replacement_serial
        +CharField status
        +DateField date_issued
        +DateField date_replaced
        +TextField comments
        +ForeignKey asset
    }

    class ExternalInventory {
        +CharField external_id
        +CharField inventory_number
        +CharField name
        +CharField serial_number
        +CharField person_id
        +CharField person_name
        +CharField location_code
        +CharField location
        +CharField department_code
        +CharField project_code
        +CharField user_name
        +TextField user_note
        +CharField split_asset
        +CharField status
        +ManyToManyField assets
        +get_status_color()
        +get_status_display()
    }

    AssetType --> Asset : "type"
    Asset --> AssetService : "asset"
    Asset --> RMA : "asset"
    Asset --> Probe : "serial match"
    Asset --> ExternalInventory : "M2M assets"
    Contract --> Asset : "order_contract"
    Contract --> AssetService : "contract"
    Contractor --> Contract : "contractor"
    Contract --> Invoice : "contract"
    Contract --> Contract : "parent (subcontract)"
    ExternalInventory --> Asset : "assets"

    Asset --> Site : "assigned_object"
    Asset --> Location : "assigned_object"
    Asset --> Rack : "assigned_object"
    Asset --> Device : "assigned_object"
    Asset --> Module : "assigned_object"

Loading

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Data Models

String Representations & Readability

All models have optimized __str__ methods designed for human readability and easy searching without relying on primary keys. The format is intuitive and includes contextual information relevant to each model type.

Design Principles:

• Natural key first: Most distinguishing identifier appears first (e.g., RMA number before asset)
• Context in parentheses: Related information in (parentheses) for clarity
• Hierarchy in brackets: Parent/child or relationship context in [brackets]
• No PK prefix: Primary keys omitted for cleaner, more searchable text
• Status visibility: Important status information included where relevant

String Representation Examples:

Model	Format	Example
Asset	partnumber [serial] (vendor)	PROD-123 [SN12345] (Dell)
Probe	serial - name	SN12345 - Server-01
Contractor	name (company) [tenant]	John Doe (ACME Corp) [Tenant1]
Contract	name (internal_name) [Sub: parent] via contractor	Main Contract (MC-001) via ACME Corp
Invoice	name (contract_name) [project] price currency	Invoice-Q1 (Main Contract) [PRJ-001] 5000.00 EUR
AssetService	asset_serial (contract_name) [category]	SN12345 (Service Contract) [Maintenance]
RMA	RMA#number asset_serial [status]	RMA#12345 PROD-123 [SN12345] [Approved]
AssetType	name (description)	Server (High-performance computing)
ExternalInventory	inventory_number name [SN: serial] → person_name	INV-001 Server Hardware [SN: ABC123] → John Smith

Search Optimization: These representations are optimized for text-based searching in:

• NetBox admin UI dropdowns and choice fields
• Search bars and filters
• API response bodies
• Logs and audit trails
• Reports and exports

The absence of primary key prefixes makes searching by name, serial number, or other identifying fields significantly easier.

Description Fields & UI Display

Most models in the Inventory Monitor plugin include a description field that provides additional context and details. These descriptions are automatically displayed in form choice fields (dropdowns) thanks to NetBox's built-in JavaScript functionality.

Models with Description Fields:

• Asset: Asset description
• AssetType: Asset type description
• Probe: Discovery information and probe notes
• Contractor: Contractor company/vendor description
• Contract: Contract terms and conditions summary
• Invoice: Invoice notes and project references
• AssetService: Service scope and terms

How It Works: When you're selecting from a choice field in a form (e.g., selecting an Asset Type, selecting a Contract, or selecting a linked Probe record), the description field is automatically shown as secondary text below the primary identifier in the dropdown. This makes it easier to identify and select the correct item without having to navigate to the detail page.

Example:

Asset Type Dropdown:
┌─────────────────────────────────────┐
│ #1: Server                          │
│ High-performance computing          │  ← Description shown in gray
│                                     │
│ #2: Network Equipment               │
│ Networking devices                  │  ← Description shown in gray
└─────────────────────────────────────┘

String Representations: All models use optimized string representations for human readability and searchability (see String Representations & Readability section above):

• Format varies by model type to show the most relevant identifying information
• Natural keys appear first (serial numbers, contract names, RMA numbers)
• Related context is shown in parentheses or brackets
• Primary keys are omitted for cleaner text display

Core Models

Asset

The central model representing physical or logical inventory items.

Key Fields:

• serial: Unique identifier for the asset (required)
• partnumber: Manufacturer part number
• description: Asset description
• assignment_status: Current assignment status (reserved, deployed, loaned, stocked)
• lifecycle_status: Lifecycle stage (new, in_stock, in_use, in_maintenance, retired, disposed)
• assigned_object: Generic foreign key to NetBox objects (Device, Site, Location, Rack, Module)
• type: Link to AssetType for categorization
• order_contract: Associated purchase contract
• project: Project identifier
• vendor: Vendor name
• quantity: Number of items (default: 1, must be ≥ 0)
• price: Asset purchase price (DecimalField, nullable, must be ≥ 0)
• currency: Price currency (CharField, nullable - required only when price is set and non-zero)
• warranty_start/end: Warranty period tracking
• comments: Additional notes

Special Features:

• Probe status integration with is_recently_probed() method
• Generic assignment to Site, Location, Rack, Device, Module via GenericForeignKey
• Integration with External Inventory systems via many-to-many relationship
• Multi-currency support with configurable currency codes and symbols
• Currency validation enforced: if price is set (non-zero), currency is required
• Deletion protection: Cannot delete an Asset with an order_contract (prevents orphaned contract references). User must clear the contract first. Also prevents deletion when linked to external inventory items.
• External inventory assignment management with dedicated form
• Comprehensive filtering including external inventory number search
• Probe matching via serial number (current and RMA serials)

Probe

Discovery and monitoring data collection points populated by external scripts (e.g., SNMP discovery tools).

Key Fields:

• time: Timestamp of the probe data collection (last probe time)
• creation_time: Timestamp when the probe was first discovered (first discovery)
• serial: Device serial number - links to Asset via serial number matching
• name: Device name or description
• part: Part number or model identifier
• category: Probe type/category classification
• device_descriptor, site_descriptor, location_descriptor: Context information from discovery
• device, site, location: Foreign keys to actual NetBox objects (if resolved)
• description: Additional discovery information
• comments: User notes about the probe
• discovered_data: JSON field for flexible data storage from external tools

Features:

• Many-to-many probe matching: matches by current serial, original RMA serial, and replacement RMA serial
• is_recently_probed() method for status indicators
• Used to find: what's actually deployed vs. what's in inventory
• Helps detect duplicates and unrecorded assets
• First discovery and last probe times tracked separately

Note: Probe data is populated by external discovery scripts, not generated by the plugin itself.

Contract & Contractor

Business relationship management with full currency support.

Contractor Features:

• name: Contractor/vendor name (required)
• company: Company legal name
• address: Business address
• description: Contractor description and notes
• tenant: Optional NetBox tenant association for multi-tenant deployments
• comments: Additional contractor information
• Searchable by name, company, address, description, and tenant

Contract Features:

• name: Contract identifier (required)
• name_internal: Internal reference name (required)
• type: Contract type (supply, order, service, other)
• description: Contract description and terms summary
• price: Contract value (DecimalField, nullable)
• currency: Contract currency (CharField, nullable - required only when price > 0)
• signed: Date contract was signed
• accepted: Date contract was accepted
• invoicing_start/end: Invoicing period dates
• contractor: Foreign key to Contractor/Vendor
• parent: Self-referential FK for subcontracts (one level only)
• comments: Contract notes

Validation Rules:

• Hierarchical contracts (parent/child relationships) - one level only (subcontract cannot itself have a parent)
• Subcontract can have a different contractor than the parent (allows complex procurement hierarchies)
• Price-Currency validation: If price is set (non-zero), currency is required; if currency is set, price must be set
• invoicing_start must not be after invoicing_end
• Convenience properties: contract_type returns "subcontract" vs "contract"

Invoice Tracking:

• Invoice records tied to contracts with name, internal name, project, and description
• Multi-currency support for invoices (invoice_price, currency)
• Invoicing date range tracking (invoicing_start, invoicing_end)
• Full searchability across all invoice fields

RMA (Return Merchandise Authorization)

Complete RMA workflow management with serial number tracking.

Key Fields:

• rma_number: RMA reference number (unique when provided, optional for draft RMAs)
• asset: Foreign key to Asset being returned/replaced (required)
• original_serial: Serial number of the failed/returned hardware
• replacement_serial: Serial number of the replacement hardware
• status: RMA status (pending, shipped, received, investigating, approved, rejected, completed)
• date_issued: When the RMA was created
• date_replaced: When the replacement was installed/received
• issue_description: Description of the issue with the asset (required)
• vendor_response: Vendor response/resolution details

Key Features:

• Flexible RMA numbering: rma_number supports NULL values for draft RMAs, enforces uniqueness only on non-empty values (via UniqueConstraint)
• Automatic serial tracking: original_serial auto-populated from asset when RMA created
• Automatic probe matching: both original and replacement serials are used for probe matching
• Asset lifecycle tracking: helps maintain historical record of hardware replacements
• Bidirectional serial tracking: enables finding all probes related to an asset through its RMA history
• Auto-update asset serial: When RMA status changes to COMPLETED, asset serial is automatically updated to replacement_serial
• Status workflow: move through RMA lifecycle states (pending → shipped → received → investigating → approved/rejected → completed)
• Composite display using str_no_pk() to avoid ID duplication in string representation
• Integration with Asset: allows viewing all RMAs for an asset including serial changes

AssetService

Service and maintenance contract tracking with multi-currency support.

Key Fields:

• service_start: Service contract start date
• service_end: Service contract end date
• service_price: Service cost (DecimalField, nullable)
• service_currency: Service currency (CharField, nullable - required only when service_price > 0)
• service_category: Service category/type classification
• service_category_vendor: Vendor for the service category
• description: Service scope and terms description
• asset: Foreign key to Asset being serviced
• contract: Foreign key to related Contract
• comments: Service notes

Features:

• Service period management with date tracking
• Pricing with multi-currency support (service_price, service_currency)
• Category and vendor tracking for service classification
• Price-Currency validation: Currency is required only when service price is set
• Links to both Assets and Contracts for complete service history
• Date status tracking for service lifecycle (upcoming, active, completed)
• Composite display using str_no_pk() to avoid ID duplication when both asset and contract are linked
• Searchable by asset, contract, description, dates, and price ranges

ExternalInventory

Integration with external inventory management systems.

Key Fields:

• external_id: Unique identifier from external system
• inventory_number: Asset number from external system
• name: Item name or description
• serial_number: Serial or production number
• person_id/person_name: Responsible person information
• location_code/location: Location information
• department_code: Department code
• project_code: Project code
• user_name/user_note: User information and notes
• split_asset: Whether this is a split/shared asset
• status: Current status code (configurable via plugin settings)
• assets: Many-to-many relationship with Assets (handles splits and mappings)

Features:

• Many-to-many relationship with Assets (one external record can map to multiple internal assets for splits)
• Configurable status display with labels and colors (via plugin settings)
• Dynamic status tooltips with customizable templates
• Project code tracking for accounting/billing
• RMA integration: external_id used for RMA matching and display
• Comprehensive filtering by all fields
• Status methods: get_status_color() and get_status_display() for UI rendering
• Deletion protection: Cannot delete external inventory items that have associated assets (prevents orphaned references)

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Installation

Requirements

• NetBox 4.4.0 or higher
• Python 3.10 or higher

From PyPI (Recommended)

pip install inventory-monitor

From Source

git clone https://github.com/CESNET/inventory-monitor-plugin.git
cd inventory-monitor-plugin
pip install .

NetBox Configuration

1. Add the plugin to your NetBox configuration.py:

PLUGINS = [
    "inventory_monitor",
]

2. Run database migrations:

python manage.py migrate

3. Restart NetBox services:

sudo systemctl restart netbox netbox-rq

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Upgrade Guide

Upgrading to v12.0.0

Version 12.0.0 brings full NetBox v4 compatibility with significant internal changes:

Breaking Changes

None - this version maintains full backward compatibility with existing data and APIs.

Migration Details

NetBox v4 API Update (ObjectType Migration)

Starting with NetBox v4, the plugin has been updated to use NetBox's new ObjectType API instead of Django's deprecated ContentType. This is an internal change with no user-facing impact:

• ✅ All asset assignments continue to work as before (Device, Site, Location, Rack, Module)
• ✅ All API endpoints remain compatible and functional
• ✅ All existing data is automatically compatible
• ✅ Search functionality expanded to include Module in searchable object types
• ✅ Database schema unchanged - no data migration required

Technical Details:

The following components have been updated for NetBox v4 compatibility:

• API Serializers: Updated to use ObjectType for assigned object handling
• Filtersets: Enhanced asset search now includes Module filtering
• Forms: Updated assignment object handling for NetBox v4 API
• Template Tags: Updated for ObjectType-based model lookups
• Template Content: Updated caching system for hierarchical asset views

Plugin Compatibility Fix

The plugin now properly handles tag field reverse accessor conflicts when multiple inventory plugins are installed simultaneously. All models now use unique related_name values for their tags fields to prevent Django's fields.E304 reverse accessor clash errors.

• ✅ Resolves conflicts with other inventory plugins (e.g., ARNES netbox_inventory)
• ✅ Maintains full tagging functionality
• ✅ No user-facing changes required

Upgrade Steps

1. Backup your database (recommended)
2. Update the plugin:

   pip install --upgrade inventory-monitor

3. No manual migration required - the plugin automatically handles the transition
4. Restart NetBox services:

   sudo systemctl restart netbox netbox-rq

Verification

After upgrading, verify that:

• Assets display correctly in the NetBox interface
• Asset search returns expected results including Module assignments
• API requests to asset endpoints work as expected
• No errors appear in NetBox logs

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Configuration

Plugin Settings

Configure the plugin in your NetBox configuration.py:

PLUGINS_CONFIG = {
    "inventory_monitor": {
        # Probe Status Settings
        "probe_recent_days": 7,  # Days to consider probe "recent"
        
        # Currency Settings
        "currencies": [
            ("CZK", "Czech Koruna", "Kč"),
            ("EUR", "Euro", "€"),
            ("USD", "US Dollar", "$"),
            ("GBP", "British Pound", "£"),
            ("JPY", "Japanese Yen", "¥"),
        ],
        "default_currency": "EUR",  # Default currency for new records
        
        # External Inventory Status Configuration (Optional)
        "external_inventory_status_config": {
            "1": {"label": "Active", "color": "success"},
            "0": {"label": "Pending Activation", "color": "warning"},
            "2": {"label": "Decommissioned", "color": "danger"},
        },
        
        # Custom tooltip template for status display (Optional)
        "external_inventory_tooltip_template": "<span class='badge text-bg-{color}'>{code}</span> {label}",
    }
}

Configuration Options

Probe Status Settings

• probe_recent_days (default: 7): Number of days to consider a probe "recent". Affects visual indicators and status badges.

Currency Settings

• currencies (default: see example above): List of available currencies for all financial models (Assets, Contracts, Invoices, AssetServices). Each item is a tuple of (currency_code, display_name, symbol).
  • currency_code: Currency identifier (e.g., "EUR", "USD", "CZK") - no length restrictions
  • display_name: Human-readable name shown in forms
  • symbol: Currency symbol for display (e.g., "€", "$", "Kč") - optional (if omitted, currency code is used)
• default_currency (default: "EUR"): Default currency code used when creating new records. Must match one of the codes in the currencies list.

Price and Currency Validation:

• Price fields are DecimalField (max_digits=19, decimal_places=2, nullable)
• price = None: No pricing information - currency optional
• price = 0: Free/no charge - currency optional
• price > 0: Actual cost - currency required and validated in model's clean() method
• Applies to: Asset.price, Contract.price, Invoice.price, AssetService.service_price

External Inventory Status Configuration

• external_inventory_status_config (optional): Maps status codes to display labels and Bootstrap colors. If not configured, status displays as-is without special formatting.
• external_inventory_tooltip_template (optional, default: "<span class='badge text-bg-{color}'>{code}</span> {label}"): Template string for formatting status tooltips

Status Configuration Structure:

{
    "status_code": {
        "label": "Human readable label",
        "color": "bootstrap_color_class"  # primary, secondary, success, danger, warning, info, light, dark
    }
}

Template Variables:

• {code}: The status code
• {label}: The display label from configuration
• {color}: The Bootstrap color class

How it works:

• ExternalInventory model provides get_status_color() and get_status_display() methods
• Status badge shown in tables using configured colors
• Tooltip generated dynamically from all configured statuses
• Form help text automatically populated with available status codes
• If not configured, displays raw status value without special formatting

Integration with NetBox Attachments

For file attachments, install and configure netbox-attachments:

pip install netbox-attachments

Customizing Field Choices

The plugin provides several configurable choice fields that can be customized via NetBox's FIELD_CHOICES configuration. This allows you to replace default choices or extend them with additional options.

Available Choice Fields

Asset Model:

• inventory_monitor.Asset.assignment_status: Assignment status (Reserved, Deployed, Loaned, Stocked)
• inventory_monitor.Asset.lifecycle_status: Lifecycle status (New, In Stock, In Use, In Maintenance, Retired, Disposed)

Contract Model:

• inventory_monitor.Contract.type: Contract type (Supply, Order, Service, Other)

RMA Model:

• inventory_monitor.RMA.status: RMA status (Pending, Shipped to Vendor, Received by Vendor, Under Investigation, Approved, Rejected, Completed)

Default Choices Reference

Asset Assignment Status (inventory_monitor.Asset.assignment_status):

[
    ('reserved', 'Reserved', 'cyan'),
    ('deployed', 'Deployed', 'green'),
    ('loaned', 'Loaned', 'blue'),
    ('stocked', 'Stocked', 'gray'),
]

Asset Lifecycle Status (inventory_monitor.Asset.lifecycle_status):

[
    ('new', 'New', 'green'),
    ('in_stock', 'In Stock', 'blue'),
    ('in_use', 'In Use', 'cyan'),
    ('in_maintenance', 'In Maintenance', 'orange'),
    ('retired', 'Retired', 'red'),
    ('disposed', 'Disposed', 'gray'),
]

Contract Type (inventory_monitor.Contract.type):

[
    ('supply', 'Supply Contract', 'green'),
    ('order', 'Order', 'red'),
    ('service', 'Service Contract', 'orange'),
    ('other', 'Other', 'blue'),
]

RMA Status (inventory_monitor.RMA.status):

[
    ('pending', 'Pending', 'yellow'),
    ('shipped', 'Shipped to Vendor', 'blue'),
    ('received', 'Received by Vendor', 'blue'),
    ('investigating', 'Under Investigation', 'blue'),
    ('approved', 'Approved', 'green'),
    ('rejected', 'Rejected', 'red'),
    ('completed', 'Completed', 'green'),
]

Customization Examples

Replace Asset Assignment Status choices (in configuration.py):

FIELD_CHOICES = {
    'inventory_monitor.Asset.assignment_status': (
        ('reserved', 'Reserved for Order', 'info'),
        ('active', 'Active/Deployed', 'success'),
        ('storage', 'In Storage', 'warning'),
        ('disposal', 'Pending Disposal', 'danger'),
    )
}

Extend (append to) Asset Lifecycle Status choices:

FIELD_CHOICES = {
    'inventory_monitor.Asset.lifecycle_status+': (
        ('quarantine', 'Quarantine', 'dark'),
        ('damaged', 'Damaged', 'danger'),
    )
}

Replace Contract Type choices:

FIELD_CHOICES = {
    'inventory_monitor.Contract.type': (
        ('purchase', 'Purchase Agreement', 'success'),
        ('maintenance', 'Maintenance Contract', 'info'),
        ('warranty', 'Warranty', 'primary'),
        ('lease', 'Lease Agreement', 'warning'),
    )
}

Extend RMA Status choices:

FIELD_CHOICES = {
    'inventory_monitor.RMA.status+': (
        ('refund', 'Refunded', 'success'),
        ('warranty_claim', 'Warranty Claim', 'info'),
    )
}

Available Colors: blue, indigo, purple, pink, red, orange, yellow, green, teal, cyan, gray, black, white

Alternatively, Bootstrap semantic colors are also supported: primary, secondary, success, danger, warning, info, light, dark

For more information on NetBox field choice configuration, see the NetBox documentation.

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Usage

Accessing the Plugin

After installation, the plugin adds an "Inventory Monitor" section to the NetBox navigation menu with the following sections:

Assets

• Assets: Main asset inventory management
• Asset Types: Asset categorization and classification
• RMA: Return Merchandise Authorization tracking
• External Inventory: External system integration
• Services: Asset service and maintenance contracts

Network Probe

• Probes: Discovery and monitoring data
• Data Locations: Probe data organization

Contracts

• Contractors: Vendor and service provider management
• Contracts: Business agreement tracking
• Invoices: Billing and invoice management

Basic Workflow

1. Set up Asset Types: Define categories for your assets
2. Add Contractors: Register vendors and service providers
3. Create Contracts: Define business agreements
4. Register Assets: Add inventory items with full metadata
5. Populate Probe Data: Use external scripts (SNMP, discovery tools) to populate monitoring data
6. Track Services: Manage maintenance and service contracts
7. Process RMAs: Handle return merchandise authorizations

Probe Status Monitoring

The plugin provides visual feedback for probe status:

• Green indicators: Recent probes (within configured days)
• Red indicators: Stale probes (older than configured threshold)
• Status badges: Clear visual indicators in asset lists and details

Asset Assignment

Assets can be assigned to any NetBox object using GenericForeignKey:

• Devices
• Sites
• Locations
• Racks
• Modules

External Inventory Assignment

The plugin provides a dedicated form (AssetExternalInventoryAssignmentForm) for managing the many-to-many relationship between Assets and External Inventory items. This form:

• Skips unrelated model validation - Overrides _post_clean() to avoid validating price/currency when only managing external inventory relationships
• Uses clean_fields() instead of full_clean() - Prevents cross-field validation errors for fields not in the form
• Manages only the many-to-many relationship - Doesn't modify other Asset fields like price, currency, serial, etc.
• Creates snapshots - Automatically creates snapshots of ExternalInventory items when relationships change
• Accessible via Asset detail page - "Edit External Inventory" button provides direct access

This specialized form prevents validation errors like 'AssetExternalInventoryAssignmentForm' has no field named 'currency' that would occur if the full Asset model validation ran.

---

Development

Architecture Overview

The plugin follows NetBox plugin best practices:

Models Architecture

Asset ←→ Probe (via serial number matching)
Asset → AssetType
Asset → Contract (order_contract)
Asset ← GenericForeignKey (assigned to Device, Site, Location, Rack, Module)
Asset ←→ RMA (via serial numbers: original_serial, replacement_serial)
Asset ←→ ExternalInventory (many-to-many via assets field)
Asset ← AssetService (via asset ForeignKey)

Contract → Contractor (via contractor ForeignKey)
Contract → Contract (parent, self-referential for hierarchical contracts)
Contract ← Invoice (via contract ForeignKey)
Contract ← AssetService (via contract ForeignKey)

ExternalInventory ←→ Asset (many-to-many relationship)
ExternalInventory ← RMA (matched via external_id for display)

Key Components

1. Models: Core business logic with probe status methods, currency validation, date status mixins
2. Views: Standard NetBox generic views (ObjectView, ObjectListView, ObjectEditView, ObjectDeleteView, BulkEditView, BulkImportView, BulkDeleteView)
3. Tables: Django-tables2 with probe status indicators, color-coded status badges, custom column templates
4. Forms: NetBox forms with custom validation, currency choices, specialized assignment forms
5. Filtersets: Comprehensive filtering for all models with custom lookups
6. Templates: Custom templates with integrated status visualization, HTMX support for dynamic updates
7. API: DRF-based REST API following NetBox patterns with full CRUD operations
8. GraphQL: Strawberry GraphQL schema with queries for all models
9. Template Tags: Custom template tags for status display and external inventory tooltips
10. Settings Helpers: Centralized configuration access via settings.py module

Performance Considerations

• Database Optimizations: Proper indexing on frequently queried fields (serial, inventory_number, status, etc.)
• Query Optimization: Use of select_related() and prefetch_related() in views and tables
• Caching: Consider caching probe status for large asset lists
• M2M Relationships: External inventory assignments use efficient many-to-many queries

Settings Access Pattern

# Recommended approach - use helper functions
from inventory_monitor.settings import (
    get_probe_recent_days,
    get_currency_choices,
    get_external_inventory_status_config_safe,
    get_external_inventory_tooltip_template,
)

days = get_probe_recent_days()
currencies = get_currency_choices()
status_config, is_configured = get_external_inventory_status_config_safe()
tooltip_template = get_external_inventory_tooltip_template()

# Alternative approach - direct settings access
from inventory_monitor.settings import get_plugin_settings
settings = get_plugin_settings()
days = settings.get("probe_recent_days", 7)

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License

This project is licensed under the MIT License. See the LICENSE file for more details.

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Acknowledgments

• Built for the NetBox ecosystem
• Part of the CESNET infrastructure management toolkit