Langflow on Jamie Ede

Self-hosting Langflow behind a public static site

Fri, 22 May 2026 16:00:00 +0000

Astra Docs Chat is public on Cloudflare Pages. Langflow runs on a private instance: reachable from the Pages Function proxy, not from browsers directly.

This post covers the ops shape I use: Dockge/compose, PostgreSQL persistence, environment variables, CORS as belt-and-braces, and what you expose vs keep internal.

Series: Building Astra Docs Chat · Proxy pattern

Public chat: Astra Docs Chat

Topology ¶

Internet → jamieede.com (Hugo + Pages Functions)
              ↓ HTTPS + x-api-key (server-side only)
           Langflow (private host / tunnel; URL not in HTML or JS)
              ↓
           OpenAI (embeddings), DeepSeek (chat), Astra DB (vectors)

Visitors never receive the Langflow hostname in HTML or JS. DevTools on /astra-chat should show only same-origin /api/astra-chat (proxy verification ).

Swapping DeepSeek in for OpenAI chat in a Langflow RAG flow

Fri, 22 May 2026 14:00:00 +0000

The Langflow DataStax RAG template ships with an OpenAI chat node. For Astra Docs Chat , I replaced it with DeepSeek for streaming answers: cheaper at volume, acceptable on technical Q&A over retrieved docs.

Context: Building Astra Docs Chat · Langflow chat flow · Astra DB vector store

Embeddings stayed on OpenAI text-embedding-3-small: only the generation step changed. See chunking and embedding post for why those stay paired.

Try it: Astra Docs Chat

Using Astra DB as the vector store for a DataStax docs RAG chat

Fri, 22 May 2026 12:00:00 +0000

For Astra Docs Chat , the subject matter is Astra DB Serverless: using Astra as the vector store was the natural fit, and Langflow’s DataStax bundle already wired up ingest and search components.

Overview: Building Astra Docs Chat · Langflow flows · Batch ingest

Try it: Astra Docs Chat

Collection setup ¶

Production values in the Langflow flow:

Field	Value
Collection name	`datastax_astra_docs`
Keyspace	`default_keyspace`
Same collection	Ingest flow writes; chat flow reads

First ingest into an empty collection is simplest. Re-runs append unless you configure deletion/upsert fields in the AstraDB component.

Chunking and embedding technical documentation for RAG

Fri, 22 May 2026 10:00:00 +0000

“271 pages” is not “271 vectors.” Split settings and embedding model choice determine whether Astra Docs Chat retrieves the right paragraph when you ask about PCU groups, hybrid search, or collection APIs.

Context: Building Astra Docs Chat · Langflow ingest flow · Batch ingest

Try retrieval in production: Astra Docs Chat

Shape of the corpus ¶

Each file in my local pages/ export is trafilatura-extracted markdown from Astra DB Serverless docs :

Re-ingesting a RAG doc corpus when upstream docs change

Thu, 21 May 2026 16:00:00 +0000

The Astra Docs Chat corpus was loaded once. DataStax ships doc updates regularly; v1 does not auto-refresh. This post outlines a repeatable re-ingest strategy when the markdown export changes: what to detect, how to use existing resume tooling, and when full rebuild beats incremental upsert.

Series: Building Astra Docs Chat · Batch ingest script · Chunking and embedding

Try the chat: Astra Docs Chat

When manual re-ingest is enough ¶

For a personal reference tool, running ingest after major doc releases (or when answers feel stale) may be sufficient. No cron, no diff pipeline, just:

Building a streaming chat UI in Hugo without React or an iframe

Thu, 21 May 2026 14:00:00 +0000

Langflow ships an embed widget. For Astra Docs Chat I wanted a full page that matches the rest of jamieede.com: same header, same typography, no iframe chrome. This post covers the Hugo layout and the vanilla JavaScript that streams markdown answers from /api/astra-chat.

Series context: Building Astra Docs Chat

Related: Proxy · Langflow chat flow · DeepSeek swap

The API contract this UI expects is documented in Proxying Langflow from Cloudflare Pages Functions .

Docs-only guardrails when RAG retrieval finds nothing

Thu, 21 May 2026 12:00:00 +0000

When Astra Docs Chat cannot find relevant chunks in Astra DB, the model may still answer from general knowledge: confident, plausible, and sometimes wrong for Astra-specific APIs. The parent post flagged tightening this with a stricter “docs only” prompt. This post covers practical guardrails at the prompt, retrieval, flow, and UX layers.

Context: Building Astra Docs Chat

Status: planned for v2; not deployed in current production chat.

Langflow RAG over Astra DB: ingest and chat flows

Wed, 20 May 2026 16:00:00 +0000

The overview of Astra Docs Chat names Langflow once and moves on: ingest graph, chat graph, done. This post opens the hood: component chains, two published endpoints, where API keys live, and why orchestration stayed in Langflow instead of a Cloudflare Worker.

Start here if you missed the big picture: Building Astra Docs Chat

Related: Batch ingest · Proxy

Two endpoints, one product ¶

Endpoint	Purpose	Called by
`datastax-astra-ingest`	File → vectors in Astra DB	Local batch ingest script (batch ingest post )
`datastax-astra-chat`	Question → retrieve → LLM answer	Pages Function `/api/astra-chat` (proxy post )

Splitting ingest and chat keeps the public surface minimal. Visitors never trigger file upload or embedding: only the retrieval + generation path.

Batch-ingesting hundreds of markdown files through Langflow

Wed, 20 May 2026 14:00:00 +0000

Astra Docs Chat only works if the documentation already lives in a vector store. The parent post summarised that as a one-time batch job: export markdown, run an ingest flow per file, resume on failure. This post is the Langflow API pattern behind that summary.

The crawl and batch scripts live on my machine only (not published as a repo). What follows is enough to build your own ingest loop; filenames and flags match what I run locally.

Proxying Langflow from Cloudflare Pages Functions

Wed, 20 May 2026 12:00:00 +0000

When I built Astra Docs Chat , the overview post described the stack in one paragraph: Hugo page on the front, Langflow and Astra DB behind it. The piece that makes that safe for a public site is small and easy to skip over: a Cloudflare Pages Function at /api/astra-chat that proxies chat requests to a private Langflow instance.

This post is that piece in detail: why the browser never talks to Langflow directly, what the proxy validates, how streaming is translated, and how to check that secrets stay server-side.

Building IBM DataStax Astra Docs Chat: asking DataStax docs questions in plain English

Wed, 20 May 2026 10:00:00 +0000

After working with distributed databases at IBM DataStax, I kept doing the same thing: open five doc tabs, search, skim, repeat. The official Astra DB Serverless documentation is thorough, but there is just a lot of it.

I wanted a single place to ask normal questions (How do I create a collection?, What are PCU groups?, How does hybrid search work?) and get answers grounded in the real docs, not a model’s best guess from training data.