$ show mat/besticon
Besticon is a Go-based application and library designed to discover and generate website icons (favicons, apple-touch-icons, etc.). It functions as a monolithic service that can be deployed as a web server, a CLI tool, or imported as a library. The core logic scans HTML for icon links, parses .ico files, extracts dominant colors from images, and generates letter-based placeholder icons when no icons are found. It exposes an HTTP API with endpoints for icon fetching and a web UI for demonstration. The architecture separates concerns into a core library (`besticon`), a command-line interface (`besticon/cmd.go`), and a web server (`iconserver`). The server integrates Prometheus metrics for observability and implements SSRF protection to prevent security vulnerabilities during external HTTP requests. The codebase utilizes Go's standard library for image processing and HTML parsing, with external dependencies for caching (`groupcache`) and metrics (`prometheus`). A notable engineering practice is the use of VCR (Video Cassette Recorder) cassettes for testing HTTP interactions, allowing deterministic testing without live network access. The project also employs the functional options pattern for configuration, ensuring a clean API for the library consumers. However, the `go.mod` file specifies a future Go version (1.26), which indicates a configuration anomaly that may hinder standard builds.
The LLM identified 4 files worth highlighting for reuse:
Defines the core `Besticon` struct and `IconFinder` interface. This module encapsulates the logic for scanning HTML, fetching icons, and processing images. It is self-contained and designed for reuse as a library, exposing a clean API for icon discovery without exposing internal implementation details.
Implements the functional options pattern to configure `Besticon` instances. This allows consumers to pass optional parameters (e.g., cache, logger) without requiring multiple constructors or mutable state, demonstrating idiomatic Go design for extensible APIs.
Implements a custom VCR (Video Cassette Recorder) pattern for Go to record and replay HTTP interactions. This enables deterministic integration testing without relying on external network availability, a reusable testing strategy for services that depend on external APIs.
Sets up the HTTP server, registers endpoints, and integrates Prometheus metrics. It demonstrates a standard Go web server pattern with middleware for logging and metrics, making it a reusable template for building Go-based HTTP services.