fix: preserve state across backend updates (#756)

src/queue/processes/removeCache.ts

@@ -1,26 +1,34 @@
 import { SandboxedJob } from "bullmq";
 import { getRepository as getRepositoryImport } from "../../server/database";
 import { RepoJobData } from "../index";
-import { createLogger } from "../../core/logger";
+import { createLogger, serializeError } from "../../core/logger";
 
 const logger = createLogger("queue:cache");
 
-export default async function (job: SandboxedJob<RepoJobData, void>) {
-  const {
-    connect,
-    getRepository,
-  }: {
-    connect: () => Promise<void>;
-    getRepository: typeof getRepositoryImport;
-  } = require("../../server/database");
+interface Database {
+  connect: () => Promise<void>;
+  getRepository: typeof getRepositoryImport;
+}
+
+export async function processRemoveCache(
+  job: SandboxedJob<RepoJobData, void>,
+  database?: Database
+) {
+  const { connect, getRepository }: Database =
+    database || require("../../server/database");
   try {
     await connect();
     logger.info("removing cache", { repoId: job.data.repoId });
     const repo = await getRepository(job.data.repoId);
     await repo.removeCache();
-  } catch {
-    // error already handled
-  } finally {
     logger.info("cache removed", { repoId: job.data.repoId });
+  } catch (error) {
+    logger.error("cache removal failed", {
+      ...serializeError(error),
+      repoId: job.data.repoId,
+    });
+    throw error;
   }
 }
+
+export default processRemoveCache;

src/queue/processes/removeRepository.ts

@@ -2,18 +2,21 @@ import { SandboxedJob } from "bullmq";
 import { getRepository as getRepositoryImport } from "../../server/database";
 import { RepositoryStatus } from "../../core/types";
 import { RepoJobData } from "../index";
-import { createLogger } from "../../core/logger";
+import { createLogger, serializeError } from "../../core/logger";
 
 const logger = createLogger("queue:remove");
 
-export default async function (job: SandboxedJob<RepoJobData, void>) {
-  const {
-    connect,
-    getRepository,
-  }: {
-    connect: () => Promise<void>;
-    getRepository: typeof getRepositoryImport;
-  } = require("../../server/database");
+interface Database {
+  connect: () => Promise<void>;
+  getRepository: typeof getRepositoryImport;
+}
+
+export async function processRemoveRepository(
+  job: SandboxedJob<RepoJobData, void>,
+  database?: Database
+) {
+  const { connect, getRepository }: Database =
+    database || require("../../server/database");
   try {
     await connect();
     logger.info("removing repository", { repoId: job.data.repoId });
@@ -29,9 +32,14 @@ export default async function (job: SandboxedJob<RepoJobData, void>) {
       }
       throw error;
     }
-  } catch {
-    // error already handled
-  } finally {
     logger.info("repository removed", { repoId: job.data.repoId });
+  } catch (error) {
+    logger.error("repository removal failed", {
+      ...serializeError(error),
+      repoId: job.data.repoId,
+    });
+    throw error;
   }
 }
+
+export default processRemoveRepository;

src/server/routes/conference.ts

@@ -145,6 +145,21 @@ function validateConferenceForm(conf: any) {
   }
 }
 
+// eslint-disable-next-line @typescript-eslint/no-explicit-any
+export function applyConferenceForm(
+  model: IConferenceDocument,
+  body: any,
+  isNew: boolean
+) {
+  model.name = body.name;
+  model.startDate = new Date(body.startDate);
+  model.endDate = new Date(body.endDate);
+  model.status = "ready";
+  model.url = body.url;
+  model.options = body.options;
+  if (isNew) model.repositories = [];
+}
+
 router.post(
   "/:conferenceID?",
   async (req: express.Request, res: express.Response) => {
@@ -164,13 +179,7 @@ router.post(
         isOwnerOrAdmin(model.owners, user);
       }
       validateConferenceForm(req.body);
-      model.name = req.body.name;
-      model.startDate = new Date(req.body.startDate);
-      model.endDate = new Date(req.body.endDate);
-      model.status = "ready";
-      model.url = req.body.url;
-      model.repositories = [];
-      model.options = req.body.options;
+      applyConferenceForm(model, req.body, !req.params.conferenceID);
 
       if (!req.params.conferenceID) {
         model.owners.push(user.model.id);

src/server/routes/repository-private.ts

@@ -424,6 +424,18 @@ function updateRepoModel(
   };
 }
 
+// eslint-disable-next-line @typescript-eslint/no-explicit-any
+export function hasRepositorySourceChanged(
+  model: IAnonymizedRepositoryDocument,
+  repoUpdate: any
+): boolean {
+  return (
+    repoUpdate.source.commit != model.source.commit ||
+    repoUpdate.source.branch != model.source.branch ||
+    repoUpdate.fullName != model.source.repositoryName
+  );
+}
+
 // update a repository
 router.post(
   "/:repoId/",
@@ -441,47 +453,42 @@ router.post(
 
       validateNewRepo(repoUpdate);
 
-      const r = gh(repoUpdate.fullName);
-      if (!r?.owner || !r?.name) {
-        await repo.resetSate(RepositoryStatus.ERROR, "repo_not_found");
-        throw new AnonymousError("repo_not_found", {
-          object: req.body,
-          httpStatus: 404,
-        });
-      }
-
       // Only the source repository/commit/branch backs the cached FileModel —
       // anonymization options (terms, image/link toggles, etc.) are applied on
       // the fly per request. Re-running the download queue is therefore only
       // needed when the underlying snapshot moves. Other edits (e.g. turning
       // off auto-update — see #360) just persist and return.
-      const sourceChanged =
-        repoUpdate.source.commit != repo.model.source.commit ||
-        repoUpdate.source.branch != repo.model.source.branch ||
-        repoUpdate.fullName != repo.model.source.repositoryName;
+      const sourceChanged = hasRepositorySourceChanged(repo.model, repoUpdate);
 
       updateRepoModel(repo.model, repoUpdate);
-      const repository = await getRepositoryFromGitHub({
-        accessToken: user.accessToken,
-        owner: r.owner,
-        repo: r.name,
-      });
-
-      if (!repository) {
-        await repo.resetSate(RepositoryStatus.ERROR, "repo_not_found");
-        throw new AnonymousError("repo_not_found", {
-          object: req.body,
-          httpStatus: 404,
-        });
-      }
-
-      await repository.getCommitInfo(repoUpdate.source.commit, {
-        accessToken: user.accessToken,
-      });
-      repo.model.source.repositoryId = repository.model.id;
-      repo.model.source.repositoryName = repository.fullName || repoUpdate.fullName;
 
       if (sourceChanged) {
+        const parsedRepository = gh(repoUpdate.fullName);
+        if (!parsedRepository?.owner || !parsedRepository?.name) {
+          await repo.resetSate(RepositoryStatus.ERROR, "repo_not_found");
+          throw new AnonymousError("repo_not_found", {
+            object: req.body,
+            httpStatus: 404,
+          });
+        }
+        const repository = await getRepositoryFromGitHub({
+          accessToken: user.accessToken,
+          owner: parsedRepository.owner,
+          repo: parsedRepository.name,
+        });
+        if (!repository) {
+          await repo.resetSate(RepositoryStatus.ERROR, "repo_not_found");
+          throw new AnonymousError("repo_not_found", {
+            object: req.body,
+            httpStatus: 404,
+          });
+        }
+        await repository.getCommitInfo(repoUpdate.source.commit, {
+          accessToken: user.accessToken,
+        });
+        repo.model.source.repositoryId = repository.model.id;
+        repo.model.source.repositoryName =
+          repository.fullName || repoUpdate.fullName;
         repo.model.anonymizeDate = new Date();
         await repo.remove();
       }
@@ -546,9 +553,17 @@ router.post(
           },
         }
       ).exec();
+      if (!sourceChanged) {
+        return res.json({ status: repo.status });
+      }
+
       await repo.updateStatus(RepositoryStatus.PREPARING);
       res.json({ status: repo.status });
-      await downloadQueue.add(repo.repoId, { repoId: repo.repoId }, { jobId: `repo-${repo.repoId}` });
+      await downloadQueue.add(
+        repo.repoId,
+        { repoId: repo.repoId },
+        { jobId: `repo-${repo.repoId}` }
+      );
     } catch (error) {
       return handleError(error, res, req);
     }

test/backend-reliability.test.js

@@ -0,0 +1,127 @@
+const { expect } = require("chai");
+require("ts-node/register/transpile-only");
+
+const ConferenceModel = require("../src/core/model/conference/conferences.model")
+  .default;
+const {
+  applyConferenceForm,
+} = require("../src/server/routes/conference");
+const {
+  hasRepositorySourceChanged,
+} = require("../src/server/routes/repository-private");
+const {
+  processRemoveRepository,
+} = require("../src/queue/processes/removeRepository");
+const {
+  processRemoveCache,
+} = require("../src/queue/processes/removeCache");
+
+describe("conference edits", function () {
+  const form = {
+    name: "Updated",
+    startDate: "2026-01-01",
+    endDate: "2026-02-01",
+    url: "https://example.test",
+    options: { expirationMode: "never" },
+  };
+
+  it("preserves existing repository membership", function () {
+    const existing = [{ id: "507f1f77bcf86cd799439011", addDate: new Date() }];
+    const model = new ConferenceModel({ repositories: existing });
+    applyConferenceForm(model, form, false);
+    expect(model.repositories).to.have.length(1);
+    expect(model.repositories[0].id.toString()).to.equal(existing[0].id);
+  });
+
+  it("initializes repository membership for a new conference", function () {
+    const model = new ConferenceModel();
+    applyConferenceForm(model, form, true);
+    expect(model.repositories).to.deep.equal([]);
+  });
+});
+
+describe("repository update source detection", function () {
+  const model = {
+    source: {
+      commit: "abc123",
+      branch: "main",
+      repositoryName: "owner/repo",
+    },
+  };
+
+  it("does not redownload for an option-only edit", function () {
+    expect(
+      hasRepositorySourceChanged(model, {
+        fullName: "owner/repo",
+        source: { commit: "abc123", branch: "main" },
+        options: { image: false },
+      })
+    ).to.equal(false);
+  });
+
+  it("redownloads when the commit, branch, or repository changes", function () {
+    expect(
+      hasRepositorySourceChanged(model, {
+        fullName: "owner/repo",
+        source: { commit: "def456", branch: "main" },
+      })
+    ).to.equal(true);
+    expect(
+      hasRepositorySourceChanged(model, {
+        fullName: "owner/repo",
+        source: { commit: "abc123", branch: "next" },
+      })
+    ).to.equal(true);
+    expect(
+      hasRepositorySourceChanged(model, {
+        fullName: "other/repo",
+        source: { commit: "abc123", branch: "main" },
+      })
+    ).to.equal(true);
+  });
+});
+
+describe("removal workers", function () {
+  const job = { data: { repoId: "repo-1" } };
+
+  it("rejects the repository job after recording a removal error", async function () {
+    const statuses = [];
+    const failure = new Error("storage unavailable");
+    const repo = {
+      updateStatus: async (status, message) => statuses.push([status, message]),
+      remove: async () => {
+        throw failure;
+      },
+    };
+
+    let caught;
+    try {
+      await processRemoveRepository(job, {
+        connect: async () => undefined,
+        getRepository: async () => repo,
+      });
+    } catch (error) {
+      caught = error;
+    }
+    expect(caught).to.equal(failure);
+    expect(statuses[statuses.length - 1][1]).to.equal(failure.message);
+  });
+
+  it("rejects cache jobs when cache removal fails", async function () {
+    const failure = new Error("storage unavailable");
+    let caught;
+    try {
+      await processRemoveCache(job, {
+        connect: async () => undefined,
+        getRepository: async () => ({
+          removeCache: async () => {
+            throw failure;
+          },
+        }),
+      });
+    } catch (error) {
+      caught = error;
+    }
+    expect(caught).to.equal(failure);
+  });
+});