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lfx-vllm

src/bundles/vllm/README.md

1.11.0.dev271.7 KB
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lfx-vllm

vLLM as a first-class Langflow model provider, packaged as a standalone Extension Bundle.

Registers a vLLM model provider that appears in Langflow's unified model picker alongside the built-in providers. vLLM serves an OpenAI-compatible HTTP API, so the provider reuses the ChatOpenAI / OpenAIEmbeddings classes and discovers the served models live from the server's /v1/models endpoint — the same model is therefore offered in both the Language Model and Embedding Model contexts.

Unlike a component bundle, this ships no component: it contributes a provider through the providers[] block in extension.json, which Langflow's provider registry merges into the unified model system. It edits no Langflow core files.

Configure

Set the vLLM endpoint (and, if your server requires it, an API key) under Settings → Model Providers → vLLM, or via environment variables:

  • VLLM_API_BASE — base URL of your vLLM server, e.g. http://localhost:8000 (required).
  • VLLM_API_KEY — bearer token, if your server enforces one (optional; servers without auth do not need it).

Install

bash
pip install lfx-vllm

The bundle is registered automatically via the langflow.extensions entry-point. Restart your Langflow server and select vLLM in any Language Model or Embedding Model field.

Develop

bash
cd src/bundles/vllm
pip install -e .
lfx extension validate src/lfx_vllm

Credit

Inherits the original vLLM provider contributed in #13910 by Yash Pareek (@pareek-ml). This bundle reconstructs that work on the provider-registry extension point so it ships without editing Langflow core.