higress-wasm-go-plugin_skill

Overview

This skill helps you develop Higress WASM gateway plugins using Go 1.24+ and the higress wasm-go SDK. It targets HTTP request/response processing, external service calls, Redis integration, and custom gateway logic for AI-native API gateways. The content provides templates, lifecycle details, API reference, and common patterns to accelerate plugin development and debugging.

How this skill works

The skill shows how to register a plugin, parse per-route or global YAML config (auto-converted to JSON), and implement handlers for HTTP lifecycle phases (request headers/body, response headers/body, stream done). It documents the proxywasm APIs for header/body manipulation, direct responses, flow control (pause/resume), and context storage. Examples include making asynchronous cluster HTTP calls and Redis access with built-in flow control and timeout patterns.

When to use it

• Creating a new Higress WASM plugin in Go to inspect or modify HTTP traffic
• Adding external service validation or enrichment (HTTP calls, Redis) inside the gateway
• Implementing request/response body transformations or streaming processing
• Debugging plugin lifecycle, flow control, or header/body access issues
• Building multi-level configurable plugins (global/domain/route) that rely on parsed config

Best practices

• Register plugin and handlers in init() using wrapper.SetCtx to ensure lifecycle hooks are set
• Parse per-request config with parseConfig; control plane supplies the effective config
• Never call Resume after SendHttpResponse — responses auto-resume after send
• Check HasRequestBody()/HasResponseBody() before using HeaderStopIteration to avoid deadlocks
• Return HeaderContinue on external call errors to fail open and avoid blocking requests
• Set explicit timeouts for cluster/HTTP calls (default is short) and handle timeouts gracefully

Example use cases

• Append a custom header on inbound requests when a route-level flag is enabled
• Call an authentication service during request headers phase; block or allow based on result
• Fetch rate limit state from Redis and return 429 when quota is exceeded
• Stream and transform response bodies for content filtering or watermarking
• Implement periodic health or leader-election tasks using tick functions for background work