Adds searxng support for tool calling

server/src/search/searxng.ts

@@ -0,0 +1,160 @@
+import { env } from "../env.js";
+
+const SEARXNG_TIMEOUT_MS = 12_000;
+const DEFAULT_SEARXNG_CATEGORIES = "general";
+
+export type SearxngSearchOptions = {
+  numResults: number;
+  includeDomains?: string[];
+  excludeDomains?: string[];
+};
+
+export type SearxngSearchResult = {
+  title: string | null;
+  url: string | null;
+  publishedDate: string | null;
+  summary: string | null;
+  text: string | null;
+  engines: string[];
+};
+
+export type SearxngSearchResponse = {
+  query: string;
+  requestId: null;
+  results: SearxngSearchResult[];
+};
+
+function clipText(input: string, maxCharacters: number) {
+  return input.length <= maxCharacters ? input : `${input.slice(0, maxCharacters)}...`;
+}
+
+function compactWhitespace(input: string) {
+  return input.replace(/\r/g, "").replace(/[ \t]+\n/g, "\n").replace(/\n{3,}/g, "\n\n").replace(/\s+/g, " ").trim();
+}
+
+function requireSearxngBaseUrl() {
+  if (!env.SEARXNG_BASE_URL) {
+    throw new Error("SEARXNG_BASE_URL not set");
+  }
+  return env.SEARXNG_BASE_URL.endsWith("/") ? env.SEARXNG_BASE_URL : `${env.SEARXNG_BASE_URL}/`;
+}
+
+function normalizeDomain(input: string) {
+  const trimmed = input.trim().toLowerCase();
+  if (!trimmed) return null;
+
+  try {
+    const parsed = new URL(trimmed.includes("://") ? trimmed : `https://${trimmed}`);
+    return parsed.hostname.replace(/^www\./, "");
+  } catch {
+    return trimmed.split(/[/?#]/, 1)[0]?.replace(/^www\./, "") || null;
+  }
+}
+
+function normalizeDomains(input: string[] | undefined) {
+  return Array.from(new Set((input ?? []).map(normalizeDomain).filter((domain): domain is string => Boolean(domain))));
+}
+
+function hostnameMatchesDomain(urlRaw: string | null, domain: string) {
+  if (!urlRaw) return false;
+  try {
+    const hostname = new URL(urlRaw).hostname.toLowerCase().replace(/^www\./, "");
+    return hostname === domain || hostname.endsWith(`.${domain}`);
+  } catch {
+    return false;
+  }
+}
+
+function filterResultsByDomains(results: SearxngSearchResult[], options: SearxngSearchOptions) {
+  const includeDomains = normalizeDomains(options.includeDomains);
+  const excludeDomains = normalizeDomains(options.excludeDomains);
+  return results.filter((result) => {
+    if (includeDomains.length && !includeDomains.some((domain) => hostnameMatchesDomain(result.url, domain))) return false;
+    if (excludeDomains.some((domain) => hostnameMatchesDomain(result.url, domain))) return false;
+    return true;
+  });
+}
+
+function buildSearxngQuery(query: string, options: SearxngSearchOptions) {
+  const includeDomains = normalizeDomains(options.includeDomains);
+  const excludeDomains = normalizeDomains(options.excludeDomains);
+  const includeClause =
+    includeDomains.length === 0
+      ? ""
+      : includeDomains.length === 1
+        ? `site:${includeDomains[0]}`
+        : `(${includeDomains.map((domain) => `site:${domain}`).join(" OR ")})`;
+  const excludeClause = excludeDomains.map((domain) => `-site:${domain}`).join(" ");
+  return [query, includeClause, excludeClause].filter(Boolean).join(" ");
+}
+
+function buildSearchUrl(query: string, options: SearxngSearchOptions) {
+  const url = new URL("search", requireSearxngBaseUrl());
+  url.searchParams.set("q", buildSearxngQuery(query, options));
+  url.searchParams.set("categories", DEFAULT_SEARXNG_CATEGORIES);
+  url.searchParams.set("language", "auto");
+  url.searchParams.set("safesearch", "1");
+  url.searchParams.set("format", "json");
+  return url;
+}
+
+async function fetchSearxng(url: URL, accept: string) {
+  const controller = new AbortController();
+  const timeout = setTimeout(() => controller.abort(), SEARXNG_TIMEOUT_MS);
+
+  try {
+    return await fetch(url, {
+      redirect: "follow",
+      signal: controller.signal,
+      headers: {
+        "User-Agent": "SybilBot/1.0 (+https://sybil.local)",
+        Accept: accept,
+      },
+    });
+  } finally {
+    clearTimeout(timeout);
+  }
+}
+
+function stringOrNull(value: unknown) {
+  if (typeof value !== "string") return null;
+  const normalized = compactWhitespace(value);
+  return normalized || null;
+}
+
+function stringArray(value: unknown) {
+  if (!Array.isArray(value)) return [];
+  return value.filter((item): item is string => typeof item === "string").map(compactWhitespace).filter(Boolean);
+}
+
+function mapJsonResult(result: any): SearxngSearchResult {
+  const summary = stringOrNull(result?.content) ?? stringOrNull(result?.snippet);
+  const text = summary ? clipText(summary, 700) : null;
+  return {
+    title: stringOrNull(result?.title),
+    url: stringOrNull(result?.url),
+    publishedDate: stringOrNull(result?.publishedDate) ?? stringOrNull(result?.published_date),
+    summary: summary ? clipText(summary, 1_400) : null,
+    text,
+    engines: stringArray(result?.engines ?? (typeof result?.engine === "string" ? [result.engine] : [])),
+  };
+}
+
+export async function searchSearxng(query: string, options: SearxngSearchOptions): Promise<SearxngSearchResponse> {
+  const url = buildSearchUrl(query, options);
+  const response = await fetchSearxng(url, "application/json");
+  if (!response.ok) {
+    await response.arrayBuffer();
+    throw new Error(`SearXNG JSON search failed with status ${response.status}. Verify search.formats includes json.`);
+  }
+
+  const contentType = response.headers.get("content-type")?.toLowerCase() ?? "";
+  if (!contentType.includes("application/json")) {
+    await response.arrayBuffer();
+    throw new Error(`SearXNG JSON search returned ${contentType || "unknown content type"}.`);
+  }
+
+  const data: any = await response.json();
+  const results = Array.isArray(data?.results) ? data.results.map(mapJsonResult) : [];
+  return { query, requestId: null, results: filterResultsByDomains(results, options).slice(0, options.numResults) };
+}