Object Types

Object types are the core building blocks of the MATIH ontology. Each object type represents a domain entity (such as Customer, Order, or Product) and defines its properties, relationships, governance metadata, and materialization strategy.

Source: data-plane/ontology-service/src/models/object_type.py

Object Type Model

Field	Type	Description
`id`	UUID	Unique identifier
`name`	string	Object type name (e.g., `Customer`)
`description`	string	Human-readable description
`layer`	OntologyLayer	Ontology layer (raw, staging, curated, semantic)
`status`	ObjectTypeStatus	Lifecycle status (draft, active, deprecated)
`governance`	GovernanceInfo	Ownership, classification, PII fields, retention
`properties`	list of PropertyDefinition	Typed property definitions
`relationships`	list of RelationshipDefinition	Links to other object types
`materialization`	MaterializationStrategy	How the object is physically stored

Ontology Layers

Layer	Purpose	Example
`raw`	Unprocessed source data	Raw CSV imports, API responses
`staging`	Cleaned and validated data	Deduplicated, type-cast records
`curated`	Business-ready data	Enriched, joined datasets
`semantic`	Domain model entities	Customer 360, Product catalog

Property Definition

Each property has a data type, source mapping, validation rules, and governance metadata:

Field	Type	Description
`name`	string	Property name
`data_type`	DataType	Data type (string, integer, double, boolean, date, timestamp, json)
`description`	string	Human-readable description
`required`	bool	Whether the property is mandatory
`validation`	PropertyValidation	Min/max, regex pattern, enum values
`source`	PropertySource	Source type (direct, derived, aggregated, computed)
`governance`	GovernanceInfo	Classification, PII flag

Property Validation

{
  "name": "email",
  "data_type": "string",
  "required": true,
  "validation": {
    "pattern": "^[a-zA-Z0-9._%+-]+@[a-zA-Z0-9.-]+\\.[a-zA-Z]{2,}$",
    "min_length": 5,
    "max_length": 255
  }
}

Governance Metadata

Field	Type	Description
`owner`	string	Team or user ID owning this object type
`steward`	string	Data steward responsible for quality
`classification`	Classification	PUBLIC, INTERNAL, CONFIDENTIAL, RESTRICTED
`pii_fields`	list of string	Fields containing personally identifiable information
`retention_days`	int	Data retention period (default: 365)

Relationships

Field	Type	Description
`name`	string	Relationship name (e.g., `placed_orders`)
`target_type`	string	Target object type name
`cardinality`	Cardinality	ONE_TO_ONE, ONE_TO_MANY, MANY_TO_MANY
`join_type`	JoinType	INNER, LEFT, RIGHT, FULL
`inverse_name`	string	Name of the inverse relationship

API Endpoints

POST   /v1/ontology/object-types          -- Create object type
GET    /v1/ontology/object-types          -- List object types
GET    /v1/ontology/object-types/:id      -- Get by ID
PUT    /v1/ontology/object-types/:id      -- Update object type
DELETE /v1/ontology/object-types/:id      -- Delete object type

Datasource Mapping -- Map to physical schemas
Schema Validation -- Validate object types
GraphQL API -- Query object types via GraphQL

Architecture Datasource Mapping