Asset Attributes

Concept overview

The asset attribute system provides a flexible way to define and store custom properties for different types of assets. It consists of four main components:

• AttributeType: Defines a reusable attribute template (e.g., "Power (kW)", "Manufacturer", "Installation Date")
• AssetTypeAttribute: Links an AttributeType to an AssetType, defining whether it's required and providing default values
• AssetAttributeValue: Stores the actual attribute values for a specific Asset instance
• AttributeOption: For dropdown/select attributes, defines the available options

This system allows different asset types to have different sets of attributes while maintaining consistency across assets of the same type.

Why it matters

• Flexibility: Different asset types can have completely different attribute sets without modifying the database schema
• Type safety: Each attribute has a defined data type (Text, Integer, Decimal, DateTime, Boolean, Option) with optional validation rules
• Consistency: All assets of the same type share the same attribute definitions, ensuring uniform data collection
• Defaults: Asset types can specify default values, streamlining asset creation
• Validation: Min/max ranges for numeric and datetime attributes ensure data quality

Data types

AttributeType supports six data types:

1. Text: Free-form text strings (stored in TextValue)
2. Integer: Whole numbers with optional min/max validation (stored in IntValue)
3. Decimal: Numbers with decimal places and optional min/max validation (stored in DecimalValue)
4. DateTime: Date and time values with optional min/max validation (stored in DateTimeValue)
5. Boolean: True/false values (stored in BoolValue)
6. Option: Single or multi-select from predefined options (stored as OptionId reference)

How it works

1. Define an AttributeType

First, create an AttributeType that can be reused across multiple asset types:

var powerAttribute = new AttributeType
{
    Code = "POWER_KW",
    Name = "Power (kW)",
    Description = "Rated power consumption in kilowatts",
    DataType = AttributeDataType.Decimal,
    Unit = "kW",
    MinDecimal = 0,
    MaxDecimal = 10000,
    IsMultiValued = false
};

For dropdown/select attributes:

var manufacturerAttribute = new AttributeType
{
    Code = "MANUFACTURER",
    Name = "Manufacturer",
    DataType = AttributeDataType.Option,
    IsMultiValued = false,
    Options = new List<AttributeOption>
    {
        new() { Value = "ABB", DisplayName = "ABB", SortOrder = 1 },
        new() { Value = "SIEMENS", DisplayName = "Siemens", SortOrder = 2 },
        new() { Value = "GE", DisplayName = "General Electric", SortOrder = 3 }
    }
};

2. Link to AssetType (AssetTypeAttribute)

When defining an AssetType, specify which attributes apply and whether they're required:

var pumpType = new AssetType { Title = "Centrifugal Pump" };

var pumpPowerAttribute = new AssetTypeAttribute
{
    AssetType = pumpType,
    AttributeType = powerAttribute,
    IsRequired = true,
    SortOrder = 1,
    DefaultDecimalValue = 5.5m  // Default 5.5 kW
};

var pumpManufacturerAttribute = new AssetTypeAttribute
{
    AssetType = pumpType,
    AttributeType = manufacturerAttribute,
    IsRequired = true,
    SortOrder = 2
    // No default - user must select
};

3. Store values for Assets (AssetAttributeValue)

When creating or editing an Asset, store the actual attribute values:

var myPump = new Asset { Title = "Pump P-101", AssetType = pumpType };

// Store power rating
var powerValue = new AssetAttributeValue
{
    Asset = myPump,
    AttributeType = powerAttribute,
    DecimalValue = 7.5m  // This pump is rated 7.5 kW
};

// Store manufacturer selection
var manufacturerValue = new AssetAttributeValue
{
    Asset = myPump,
    AttributeType = manufacturerAttribute,
    OptionId = abbOption.Uuid  // Selected ABB
};

Key features

Multi-valued attributes

Set IsMultiValued = true on an AttributeType to allow multiple values for a single attribute. This is useful for attributes like "Certifications" or "Supported Fluids" where an asset might have multiple applicable values.

Validation rules

• Numeric ranges: Set MinInt/MaxInt or MinDecimal/MaxDecimal to enforce valid ranges
• DateTime ranges: Set MinDateTime/MaxDateTime for date validation (e.g., installation date must be in the past)
• Required vs Optional: Use IsRequired on AssetTypeAttribute to make attributes mandatory

Units of measurement

The Unit field on AttributeType provides context for numeric attributes (e.g., "kW", "°C", "bar", "rpm"). This is informational and helps users understand what values to enter.

Default values

AssetTypeAttribute can specify default values for each data type:

• DefaultTextValue
• DefaultIntValue
• DefaultDecimalValue
• DefaultBoolValue
• DefaultDateTimeValue
• DefaultOptionId

These defaults can streamline asset creation when most assets of a type share common values.

Relationships

AttributeType
  ├─→ AttributeOptions (many)
  └─→ AssetTypeAttributes (many)

AssetType
  └─→ AssetTypeAttributes (many)
      └─→ AttributeType (one)

Asset
  └─→ AssetAttributeValues (many)
      ├─→ AttributeType (one)
      └─→ AttributeOption (optional, for Option type only)

First implementation

The initial implementation focuses on:

1. CRUD for AttributeTypes: Admin interface to define reusable attribute templates
2. AssetType configuration: When creating/editing an AssetType, specify which attributes apply and whether they're required
3. Asset forms: When creating/editing an Asset, display a dynamic form with all attributes defined by its AssetType
4. Type-appropriate inputs:
   • Text → text input
   • Integer/Decimal → numeric input with validation
   • Boolean → checkbox
   • DateTime → date/time picker
   • Option → dropdown or radio buttons

Usage in Blueprint

Backend (API)

• AttributeType management endpoints for defining attribute templates
• AssetType configuration includes attribute assignment
• Asset create/update validates attribute values against their types and requirements
• Query assets by attribute values (e.g., "find all pumps with power > 10 kW")

Frontend (Web/Mobile)

• Admin screens for managing AttributeTypes and their options
• AssetType editor shows attribute assignment with required/optional toggles
• Asset form dynamically renders appropriate input controls based on AssetType's attributes
• Display attribute values on asset detail views

Offline support

• AttributeType and AssetTypeAttribute data synced to mobile devices
• Asset attribute values can be edited offline
• Validation rules enforced locally before sync

Example scenarios

Scenario 1: Electric Motors

AttributeType: "MOTOR_POWER"
  - DataType: Decimal
  - Unit: "kW"
  - MinDecimal: 0.1
  - MaxDecimal: 500

AttributeType: "MOTOR_SPEED"
  - DataType: Integer
  - Unit: "rpm"
  - MinInt: 100
  - MaxInt: 10000

AttributeType: "MOTOR_EFFICIENCY_CLASS"
  - DataType: Option
  - Options: IE1, IE2, IE3, IE4, IE5

AssetType: "Electric Motor"
  - Requires: MOTOR_POWER (default: 5.5 kW)
  - Requires: MOTOR_SPEED (default: 1500 rpm)
  - Optional: MOTOR_EFFICIENCY_CLASS

Scenario 2: Temperature Sensors

AttributeType: "TEMP_RANGE_MIN"
  - DataType: Decimal
  - Unit: "°C"

AttributeType: "TEMP_RANGE_MAX"
  - DataType: Decimal
  - Unit: "°C"

AttributeType: "CALIBRATION_DATE"
  - DataType: DateTime

AttributeType: "SENSOR_TYPE"
  - DataType: Option
  - Options: RTD, Thermocouple, Thermistor

AssetType: "Temperature Sensor"
  - Requires: SENSOR_TYPE
  - Requires: TEMP_RANGE_MIN (default: -50)
  - Requires: TEMP_RANGE_MAX (default: 150)
  - Optional: CALIBRATION_DATE

See also

• Asset Types - How asset types categorize assets
• Assets - The assets that these attributes describe