kotoba-schema

Graph Schema Definition and Validation for Kotoba - プロセスネットワーク as GTS(DPO)+OpenGraph with Merkle DAG & PG view

Overview

kotoba-schema provides a comprehensive schema system for defining and validating graph structures in the Kotoba graph database. It supports:

Schema Definition: Define vertex types, edge types, properties, and constraints
Validation: Validate graph data against schemas
Schema Management: Register, update, and manage schemas
Migration Support: Migrate graph data between schema versions
JSON Schema Integration: Export schemas as JSON Schema for external validation

Features

✅ Graph Schema Definition (GTS-DPO compatible)
✅ Property Type System with Constraints
✅ Schema Validation Engine
✅ Schema Registry and Management
✅ Migration and Evolution Support
✅ JSON Schema Export/Import
✅ Async Support (optional)

Usage

Basic Schema Definition

use kotoba_schema::{GraphSchema, VertexTypeSchema, EdgeTypeSchema, PropertySchema, PropertyType};
use std::collections::HashMap;

// Create a new schema
let mut schema = GraphSchema::new(
    "social_graph".to_string(),
    "Social Network Graph Schema".to_string(),
    "1.0.0".to_string(),
);

// Define User vertex type
let mut user_props = HashMap::new();
user_props.insert(
    "name".to_string(),
    PropertySchema {
        name: "name".to_string(),
        property_type: PropertyType::String,
        description: Some("User's full name".to_string()),
        required: true,
        default_value: None,
        constraints: vec![PropertyConstraint::MinLength(1)],
    },
);

let user_vertex = VertexTypeSchema {
    name: "User".to_string(),
    description: Some("User account vertex".to_string()),
    required_properties: vec!["name".to_string()],
    properties: user_props,
    inherits: vec![],
    constraints: vec![],
};

schema.add_vertex_type(user_vertex);

// Validate the schema
let validation = schema.validate_schema();
assert!(validation.is_valid);

Schema Management

use kotoba_schema::SchemaManager;
use kotoba_storage::StorageManager;

// Create storage backend
let storage_manager = StorageManager::default().await?;
let backend = Arc::new(storage_manager.backend().clone());

// Create schema manager
let mut schema_manager = SchemaManager::new(backend);

// Register schema
schema_manager.register_schema(schema).await?;

// Validate graph data
let graph_data = serde_json::json!({
    "vertices": [{
        "id": "user1",
        "labels": ["User"],
        "properties": {
            "name": "John Doe"
        }
    }]
});

let validation = schema_manager.validate_graph_data("social_graph", &graph_data).await?;
assert!(validation.is_valid);

Schema Migration

use kotoba_schema::{SchemaOperations, MigrationRule, MigrationRuleType};

// Create migration rules
let migration_rules = HashMap::from([
    ("rename_username".to_string(), MigrationRule {
        rule_type: MigrationRuleType::RenameProperty,
        source_path: "username".to_string(),
        target_path: "name".to_string(),
        transformation: None,
    })
]);

// Migrate schema
let result = schema_manager.migrate_schema(
    "social_graph_v1",
    "social_graph_v2",
    migration_rules
).await?;

println!("Migrated {} graphs", result.migrated_count);

Schema Definition Language

Vertex Types

let user_vertex = VertexTypeSchema {
    name: "User".to_string(),
    description: Some("User account".to_string()),
    required_properties: vec!["id".to_string(), "name".to_string()],
    properties: HashMap::from([
        ("id".to_string(), PropertySchema {
            name: "id".to_string(),
            property_type: PropertyType::String,
            required: true,
            constraints: vec![PropertyConstraint::Pattern(r"^[a-zA-Z0-9_-]+$".to_string())],
            ..
        }),
        ("name".to_string(), PropertySchema {
            name: "name".to_string(),
            property_type: PropertyType::String,
            required: true,
            constraints: vec![PropertyConstraint::MinLength(1), PropertyConstraint::MaxLength(100)],
            ..
        }),
        ("email".to_string(), PropertySchema {
            name: "email".to_string(),
            property_type: PropertyType::String,
            required: false,
            constraints: vec![PropertyConstraint::Pattern(r"^[^@]+@[^@]+\.[^@]+$".to_string())],
            ..
        }),
        ("age".to_string(), PropertySchema {
            name: "age".to_string(),
            property_type: PropertyType::Integer,
            required: false,
            constraints: vec![PropertyConstraint::MinValue(0), PropertyConstraint::MaxValue(150)],
            ..
        }),
    ]),
    inherits: vec![],
    constraints: vec![],
};

Edge Types

let friendship_edge = EdgeTypeSchema {
    name: "FRIENDS_WITH".to_string(),
    description: Some("Friendship relationship".to_string()),
    source_types: vec!["User".to_string()],
    target_types: vec!["User".to_string()],
    required_properties: vec![],
    properties: HashMap::from([
        ("since".to_string(), PropertySchema {
            name: "since".to_string(),
            property_type: PropertyType::DateTime,
            required: false,
            ..
        }),
    ]),
    directed: true,
    constraints: vec![],
};

Property Types

String: Text data
Integer: 64-bit signed integer
Float: 64-bit floating point
Boolean: True/false values
DateTime: ISO 8601 date/time
Json: Arbitrary JSON data
Array<T>: Array of type T
Map: String-keyed map of values

Constraints

Property Constraints

MinLength(n): Minimum string length
MaxLength(n): Maximum string length
MinValue(n): Minimum numeric value
MaxValue(n): Maximum numeric value
Pattern(regex): Regular expression pattern
Enum(values): Allowed values list
Custom(name): Custom validation rule

Schema Constraints

UniqueProperty: Unique property values
Cardinality: Edge multiplicity constraints
PathConstraint: Complex path patterns
Custom: Custom schema rules

Integration with Process Network

This crate integrates with the Kotoba process network as defined in dag.jsonnet:

'schema_validator': {
  name: 'schema_validator',
  path: 'crates/kotoba-schema/src/validator.rs',
  type: 'schema',
  description: 'Graph schema validation engine',
  dependencies: ['types', 'graph_core'],
  provides: ['SchemaValidator', 'ValidationResult'],
  status: 'completed',
  build_order: 4,
},

Architecture

kotoba-schema/
├── schema.rs          # Core schema definitions
├── validator.rs       # Validation engine
├── manager.rs         # Schema management
├── registry.rs        # Schema registry
├── migration.rs       # Schema migration
└── export.rs          # JSON Schema export

Testing

cargo test -p kotoba-schema

Benchmarks

cargo bench -p kotoba-schema

License

MIT OR Apache-2.0

kotoba-schema 0.1.22