Crate drasi_source_mock 

Mock Source Plugin for drasi-lib.

This plugin provides a mock data generator for testing and development purposes. It generates synthetic data at configurable intervals, allowing you to test query behavior and reaction processing without connecting to real data sources.

Data Types

The mock source supports three data generation modes:

Counter Mode (data_type: DataType::Counter)

Generates sequentially numbered nodes with the label Counter. Each event is always an INSERT with a unique element ID (counter_1, counter_2, etc.):

Element {
    id: "counter_1",
    labels: ["Counter"],
    properties: {
        value: 1,              // Sequential integer starting at 1
        timestamp: "2024-01-15T10:30:00.123Z"  // RFC 3339 string
    },
    effective_from: 1705318200123  // Milliseconds since Unix epoch
}

Sensor Reading Mode (data_type: DataType::SensorReading { sensor_count })

Generates simulated IoT sensor readings with randomized temperature and humidity values from a configurable number of sensors (default: 5). Each node has the label SensorReading.

Key Behavior: The first reading for each sensor generates an INSERT event; subsequent readings for the same sensor generate UPDATE events. This simulates real sensor behavior where devices are discovered once then continuously report.

Element {
    id: "sensor_2",
    labels: ["SensorReading"],
    properties: {
        sensor_id: "sensor_2",
        temperature: 25.7,     // Random in range [20.0, 30.0)
        humidity: 48.3,        // Random in range [40.0, 60.0)
        timestamp: "2024-01-15T10:30:00.123Z"
    },
    effective_from: 1705318200123
}

Generic Mode (data_type: DataType::Generic) - Default

Generates generic nodes with random values and the label Generic. Each event is always an INSERT with a unique element ID:

Element {
    id: "generic_1",
    labels: ["Generic"],
    properties: {
        value: 12345,          // Random i32
        message: "Generic mock data",
        timestamp: "2024-01-15T10:30:00.123Z"
    },
    effective_from: 1705318200123456789  // Nanoseconds since Unix epoch
}

Configuration

Field	Type	Default	Description
data_type	DataType	Generic	Type of data to generate
interval_ms	u64	5000	Interval between events in milliseconds (must be > 0)

Example Configuration (YAML)

source_type: mock
properties:
  data_type:
    type: sensor_reading
    sensor_count: 10
  interval_ms: 1000

Usage Example

use drasi_source_mock::{MockSource, MockSourceConfig, DataType};

// Create configuration for sensor data at 1-second intervals
let config = MockSourceConfig {
    data_type: DataType::sensor_reading(10),
    interval_ms: 1000,
};

// Create the source
let source = MockSource::new("my-mock", config)?;

// Add to DrasiLib (ownership is transferred)
drasi.add_source(source).await?;

Testing

The mock source provides methods for unit testing without a full DrasiLib setup:

• MockSource::inject_event() - Inject custom SourceChange events (INSERT, UPDATE, DELETE) for deterministic testing scenarios
• MockSource::test_subscribe() - Subscribe to receive events directly from the source, bypassing DrasiLib’s subscription mechanism

Modules

descriptor

Mock source plugin descriptor and configuration DTOs.

Structs

MockSource

Mock source that generates synthetic data for testing and development.

MockSourceBuilder

Builder for MockSource instances.

MockSourceConfig

Configuration for a MockSource instance.

Enums

DataType

Specifies the type of synthetic data to generate.