Defining a New Report

Each BenchSpy report must implement the Reporter interface, which handles three primary responsibilities:

• Storage and retrieval (Storer interface)
• Data fetching (DataFetcher interface)
• Comparison (Comparator interface)

Reporter Interface

Definition

type Reporter interface {
	Storer
	DataFetcher
	Comparator
}

The comparison of actual performance data should not be part of the report itself. It should be done independently, ideally using Go's require and assert statements.

Storer Interface

Definition

type Storer interface {
	// Store stores the report in persistent storage and returns the path to it, or an error
	Store() (string, error)
	// Load loads the report from persistent storage based on the test name and commit/tag, or returns an error
	Load(testName, commitOrTag string) error
	// LoadLatest loads the latest report from persistent storage for the given test name, or returns an error
	LoadLatest(testName string) error
}

Usage

• If storing reports locally under Git satisfies your requirements, you can reuse the LocalStorage implementation of Storer.
• If you need to store reports in S3 or a database, you will need to implement the interface yourself.

DataFetcher Interface

Definition

type DataFetcher interface {
	// FetchData populates the report with data from the test
	FetchData(ctx context.Context) error
}

Purpose

This interface is solely responsible for fetching data from the data source and populating the report with results.

Comparator Interface

Definition

type Comparator interface {
	// IsComparable checks whether two reports can be compared (e.g., test configuration, app resources, queries, and metrics are identical),
	// and returns an error if any differences are found
	IsComparable(otherReport Reporter) error
}

Purpose

This interface ensures that both reports are comparable by verifying:

• Both use generators with identical configurations (e.g., load type, load characteristics).
• Both reports feature the same data sources and queries.

This design provides flexibility and composability, allowing you to store, fetch, and compare reports in a way that fits your specific requirements.