import { hnSearch } from "https://esm.town/v/stevekrouse/hnSearch"; import inputHeader from "https://esm.town/v/substrate/inputHeader"; import { ComputeJSON, ComputeText, sb, Substrate } from "npm:substrate"; import { z } from "npm:zod"; import { zodToJsonSchema } from "npm:zod-to-json-schema"; const substrate = new Substrate({ apiKey: Deno.env.get("SUBSTRATE_API_KEY") }); // search for HN comments using https://hn.algolia.com/api const query = "langchain"; const searchResults = await hnSearch({ query: query, numericFilters: `created_at_i>${Math.floor(Date.now() / 1000) - 60 * 60 * 24 * 7 * 4}`, tags: "comment", }); // Extract summary, sentiment, and metadata from each comment const commentInfo = z.object({ summary: z.string().describe("Summarize in a couple sentences: who is commenting, what the comment is about, how it is related to the topic."), storyTitle: z.string().describe("The story title."), forHiring: z.boolean().describe("True if the story is a Ask HN post with Who is hiring, Who wants to be hired, or Seeking freelancer in the title"), sentiment: z.enum(["positive", "neutral", "negative"]).describe("Sentiment of the post."), objectID: z.string().describe("objectID field"), }); let summaries = []; for (const hit of searchResults.hits) { summaries.push( new ComputeJSON({ prompt: `Summarize this comment and how it relates to the topic: ${query} Use "negative" sentiment for posts about API, abstraction, documentation, tutorial, general quality, slowness, or performance issues. COMMENT: ${JSON.stringify(hit)}`, json_schema: zodToJsonSchema(commentInfo), }, { cache_age: 60 * 60 * 24 }), ); } // Generate a markdown summary const markdown = new ComputeText({ prompt: sb.concat(`Below is a list of summarized comments about ${query} on HackerNews in the last week. Generate concise markdown summarizing the results. DO NOT include a title or introduction. Summarize the contents of the comment and the sentiment about ${query}. Categorize results under sentiment headers. Order from most negative to least negative within each category. Add a link to the original story URL in this format: [](https://news.ycombinator.com/item?id=) Filter out posts that are for hiring (forHiring = true). Filter out posts that do not seem to be about ${query}. Just return the markdown. Do not introduce with "Here is" or explain the output. RESULTS:\n`, // @ts-ignore ...summaries.map((s) => sb.jq(s.future.json_object, "@json")), ), model: "Llama3Instruct70B", }); const stream = await substrate.stream(markdown); // Render streaming markdown export default async function handler(req: Request): Promise { let { readable, writable } = new TransformStream(); let writer = writable.getWriter(); const textEncoder = new TextEncoder(); writer.write(textEncoder.encode(`

`)); new Promise(async () => { for await (const event of stream.get(markdown)) { if (event.object === "node.delta") { const chunk = event.data.text || ""; writer.write(textEncoder.encode(``)); } } writer.write(textEncoder.encode(``)); writer.close(); }); return new Response(readable, { headers: { "Content-Type": "text/html", }, }); }

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