Principle:Sgl project Sglang OpenAI Client Configuration
| Knowledge Sources | |
|---|---|
| Domains | LLM_Serving, API_Client, Integration |
| Last Updated | 2026-02-10 00:00 GMT |
Overview
A client configuration pattern that points the standard OpenAI Python SDK to a local SGLang server for drop-in API compatibility.
Description
SGLang's HTTP server implements OpenAI-compatible API endpoints, allowing any application built with the OpenAI Python SDK to work with SGLang by simply changing the base URL. The client configuration involves creating an openai.Client instance pointing to the SGLang server's URL with a /v1 suffix. Since SGLang does not require API key authentication by default, any string can be used as the API key.
Usage
Configure an OpenAI client when interacting with a running SGLang HTTP server from application code. This is the standard approach for online serving scenarios where the SGLang server is running as a separate process or on a different machine.
Theoretical Basis
The pattern leverages API compatibility — SGLang implements the same REST endpoints (routes, request/response schemas) as the OpenAI API. This allows:
- Zero code changes for existing OpenAI SDK users
- Standard ecosystem tooling (LangChain, LlamaIndex) works out of the box
- Client-side features (retries, streaming, async) from the OpenAI SDK are fully supported