Fall back across job sources when one can't answer

src/lib/agent/run.ts

@@ -9,9 +9,9 @@ import { isAiConfigured } from "@/lib/ai/config";
 import { AiError } from "@/lib/ai/errors";
 import { loadTaskOptions } from "@/lib/ai/task-options";
 import { scorePosting } from "@/lib/ai/tasks";
-import { searchPostings } from "@/lib/job-search";
-import { credentialsFor, loadJobSearchConfig, requestContext } from "@/lib/job-search/config";
+import { credentialsFor, loadJobSearchConfig } from "@/lib/job-search/config";
 import { JobSearchError } from "@/lib/job-search/errors";
+import { searchWithFallback } from "@/lib/job-search/find";
 import { postingKey, postingText, type FoundPosting, type SearchQuery } from "@/lib/job-search/search";
 import { startJob, type JobContext } from "@/lib/jobs/runner";
 import { logServerError } from "@/lib/log";
@@ -113,15 +113,12 @@ export async function runAgentScan({ manual }: { manual: boolean }, context: Job
 
   await context.step("Searching for new postings");
   const config = await loadJobSearchConfig();
-  const source = config.source!;
-  let postings: FoundPosting[];
-  try {
-    // The first page only: the agent never asks for a second.
-    postings = (await searchPostings(source, credentialsFor(config, source), settings.agentQuery, null, requestContext(source))).postings;
-  } catch (error) {
-    if (error instanceof JobSearchError) return finish(stopped(error.message));
-    throw error;
-  }
+  // The first page only: the agent never asks for a second. Falls back across every source with a key saved
+  // (E14-9) if the chosen one can't answer, except the Bundesagentur für Arbeit, which the agent never searches
+  // on its own (#223) whether it's chosen or not.
+  const answer = await searchWithFallback(config, config.source!, settings.agentQuery, null, { exclude: ["ARBEITSAGENTUR"] });
+  if (!answer.ok) return finish(stopped(answer.message));
+  const postings: FoundPosting[] = answer.postings;
 
   const fresh = await newPostings(postings);
   const counts = { found: postings.length, fresh: fresh.length, skipped: postings.length - fresh.length, drafted: 0 };

src/lib/job-search/find.ts

@@ -1,33 +1,97 @@
 import "server-only";
 
-import { credentialsFor, loadJobSearchConfig, requestContext } from "./config";
+import { credentialsFor, loadJobSearchConfig, requestContext, type JobSearchConfig } from "./config";
 import { JobSearchError } from "./errors";
 import { postingDetails, searchPostings } from "./index";
-import type { FoundPosting, JobSource, SearchPage, SearchProblem, SearchQuery } from "./search";
+import { JOB_SOURCES, type FoundPosting, type JobSource, type SearchPage, type SearchProblem, type SearchQuery } from "./search";
+import { SOURCE_INFO } from "./sources";
 
 // Asking a job source from Find jobs (E14-6): a page of postings, or what
 // went wrong in words for the screen. Kept searches are in
 // src/lib/posting-searches.ts.
 
+export type SourceAnswer = ({ ok: true; source: JobSource } & SearchPage) | SearchProblem;
+
 /**
- * One page for `query` from `source`, the one chosen in Settings unless
- * given (a kept search goes on with the source it ran on).
+ * The order to try sources in for a fresh search (E14-9): the one chosen in
+ * Settings first, then the rest in the order Settings lists them.
  */
-export async function askSource(
+function fallbackOrder(primary: JobSource): JobSource[] {
+  return [primary, ...JOB_SOURCES.filter((source) => source !== primary)];
+}
+
+/**
+ * One page for `query`, trying every source with a key saved — starting
+ * from `primary` — until one answers (E14-9): one source's exhausted quota,
+ * an outage, or a country it doesn't cover no longer stops a search, it
+ * just moves on to the next. A source with no key saved (or, for the
+ * Bundesagentur für Arbeit, not yet switched on) is skipped without being
+ * asked at all. Shared by askSource below and the job agent's search step
+ * (src/lib/agent/run.ts), so both get the same resilience; the agent
+ * excludes the Bundesagentur für Arbeit itself (it never searches it, #223).
+ */
+export async function searchWithFallback(
+  config: JobSearchConfig,
+  primary: JobSource,
   query: SearchQuery,
-  { source, next = null }: { source?: JobSource; next?: string | null } = {},
-): Promise<({ ok: true; source: JobSource } & SearchPage) | SearchProblem> {
+  next: string | null = null,
+  { exclude = [] }: { exclude?: readonly JobSource[] } = {},
+): Promise<SourceAnswer> {
+  // A source with no key saved (or, for the Bundesagentur für Arbeit, not yet switched on) was never asked, so it's
+  // not a failed attempt — it's skipped silently, the way it would be if it didn't exist. The one exception is the
+  // primary source itself: if nothing else is configured either, its own "add a key" message is the most useful
+  // thing to say, same as before there was anything to fall back to.
+  let primaryNotConfigured: SearchProblem | null = null;
+  const attempts: { source: JobSource; problem: SearchProblem }[] = [];
+  for (const candidate of fallbackOrder(primary)) {
+    if (exclude.includes(candidate)) continue;
+    let credentials;
+    try {
+      credentials = credentialsFor(config, candidate);
+    } catch (error) {
+      if (!(error instanceof JobSearchError)) throw error;
+      if (candidate === primary) primaryNotConfigured = { ok: false, problem: error.problem, message: error.message };
+      continue;
+    }
+    try {
+      const page = await searchPostings(candidate, credentials, query, next, requestContext(candidate));
+      return { ok: true, source: candidate, ...page };
+    } catch (error) {
+      if (!(error instanceof JobSearchError)) throw error;
+      attempts.push({ source: candidate, problem: { ok: false, problem: error.problem, message: error.message } });
+    }
+  }
+  if (attempts.length === 0) return primaryNotConfigured ?? { ok: false, problem: "off", message: "Choose where to search in Settings → Job search first." };
+  if (attempts.length === 1) return attempts[0].problem;
+  return {
+    ok: false,
+    problem: attempts[0].problem.problem,
+    message: `None of your job sources could answer. ${attempts.map((a) => `${SOURCE_INFO[a.source].name}: ${a.problem.message}`).join(" ")}`,
+  };
+}
+
+/**
+ * One page for `query` from `source`, the one chosen in Settings unless
+ * given (a kept search goes on with the exact source it ran on — its `next`
+ * cursor only means something there, so a fresh search's fallback across
+ * sources doesn't apply to "Show more").
+ */
+export async function askSource(query: SearchQuery, { source, next = null }: { source?: JobSource; next?: string | null } = {}): Promise<SourceAnswer> {
   const config = await loadJobSearchConfig();
-  const from = source ?? config.source;
-  if (!from) return { ok: false, problem: "off", message: "Choose where to search in Settings → Job search first." };
   if (!query.country) return { ok: false, problem: "no-country", message: "Choose a country to search in." };
-  try {
-    const page = await searchPostings(from, credentialsFor(config, from), query, next, requestContext(from));
-    return { ok: true, source: from, ...page };
-  } catch (error) {
-    if (error instanceof JobSearchError) return { ok: false, problem: error.problem, message: error.message };
-    throw error;
+
+  if (source) {
+    try {
+      const page = await searchPostings(source, credentialsFor(config, source), query, next, requestContext(source));
+      return { ok: true, source, ...page };
+    } catch (error) {
+      if (error instanceof JobSearchError) return { ok: false, problem: error.problem, message: error.message };
+      throw error;
+    }
   }
+
+  if (!config.source) return { ok: false, problem: "off", message: "Choose where to search in Settings → Job search first." };
+  return searchWithFallback(config, config.source, query, next);
 }
 
 /**

src/lib/posting-searches.db.test.ts

@@ -23,6 +23,8 @@ const prisma = () => db.client!;
 
 const query = { ...EMPTY_QUERY, keywords: "product designer", place: "Hamburg", country: "de" };
 const useJSearch = () => saveSettings({ jobSource: "JSEARCH", jsearchKeyEnc: encryptSecret(JOB_SOURCE_KEY, "ak_test") });
+const addAdzunaKey = () => saveSettings({ adzunaAppId: "app", adzunaKeyEnc: encryptSecret(JOB_SOURCE_KEY, "adz_test") });
+const adzunaAnswer = (results: unknown[] = []) => json({ results, count: results.length });
 
 beforeEach(async () => {
   await resetDatabase(prisma());
@@ -70,6 +72,49 @@ describe("runSearch", () => {
   });
 });
 
+describe("falling back across sources (E14-9)", () => {
+  it("moves on to the next source with a key saved when the chosen one is exhausted", async () => {
+    await useJSearch();
+    await addAdzunaKey();
+    const requests = stubFetch((request) =>
+      request.url.hostname === "api.openwebninja.com" ? json({}, { status: 429 }) : adzunaAnswer([{ id: "1", title: "Designer" }]),
+    );
+    const result = await runSearch(query);
+    expect(result).toEqual({ ok: true, id: expect.any(String) });
+    const kept = await prisma().postingSearch.findUniqueOrThrow({ where: { id: result.ok ? result.id : "" } });
+    expect(requests.filter((r) => r.url.hostname === "api.openwebninja.com")).toHaveLength(1);
+    expect(requests.filter((r) => r.url.hostname === "api.adzuna.com")).toHaveLength(1);
+    expect(kept.source).toBe("ADZUNA");
+  });
+
+  it("says so, naming each one, when every configured source fails", async () => {
+    await useJSearch();
+    await addAdzunaKey();
+    stubFetch((request) => (request.url.hostname === "api.openwebninja.com" ? json({}, { status: 429 }) : json({}, { status: 401 })));
+    const result = await runSearch(query);
+    expect(result).toMatchObject({
+      ok: false,
+      problem: "quota",
+      message: "None of your job sources could answer. JSearch: You've used up your JSearch searches for this month. Try again then, or move to a bigger plan. Adzuna: Adzuna didn't accept your key. Check it in Settings → Job search.",
+    });
+  });
+
+  it("stops at the one source saved, same as before there was anything to fall back to", async () => {
+    await saveSettings({ jobSource: "JSEARCH" });
+    expect(await runSearch(query)).toEqual({ ok: false, problem: "no-key", message: "Add your JSearch key in Settings → Job search first." });
+  });
+
+  it("doesn't fall back for Show more: it stays on the search's own source", async () => {
+    await useJSearch();
+    await addAdzunaKey();
+    stubFetch(() => json(jsearchV2Page));
+    const run = await runSearch(query);
+    const id = run.ok ? run.id : "";
+    stubFetch((request) => (request.url.hostname === "api.openwebninja.com" ? json({}, { status: 429 }) : adzunaAnswer([])));
+    expect(await showMoreFor(id)).toMatchObject({ ok: false, problem: "quota" });
+  });
+});
+
 describe("loadSearch", () => {
   it("opens a kept search without asking the source, with where each posting stands now", async () => {
     await useJSearch();