Merge pull request #292 from AikidoSec/retry-malware-db-download

Retry downloading the malware database 3 times

packages/safe-chain/src/api/aikido.js

@@ -1,5 +1,10 @@
 import fetch from "make-fetch-happen";
-import { getEcoSystem, ECOSYSTEM_JS, ECOSYSTEM_PY } from "../config/settings.js";
+import {
+  getEcoSystem,
+  ECOSYSTEM_JS,
+  ECOSYSTEM_PY,
+} from "../config/settings.js";
+import { ui } from "../environment/userInteraction.js";
 
 const malwareDatabaseUrls = {
   [ECOSYSTEM_JS]: "https://malware-list.aikido.dev/malware_predictions.json",
@@ -17,38 +22,91 @@ const malwareDatabaseUrls = {
  * @returns {Promise<{malwareDatabase: MalwarePackage[], version: string | undefined}>}
  */
 export async function fetchMalwareDatabase() {
-  const ecosystem = getEcoSystem();
-  const malwareDatabaseUrl = malwareDatabaseUrls[/** @type {keyof typeof malwareDatabaseUrls} */ (ecosystem)];
-  const response = await fetch(malwareDatabaseUrl);
-  if (!response.ok) {
-    throw new Error(`Error fetching ${ecosystem} malware database: ${response.statusText}`);
-  }
+  const numberOfAttempts = 4;
 
-  try {
-    let malwareDatabase = await response.json();
-    return {
-      malwareDatabase: malwareDatabase,
-      version: response.headers.get("etag") || undefined,
-    };
-  } catch (/** @type {any} */ error) {
-    throw new Error(`Error parsing malware database: ${error.message}`);
-  }
+  return retry(async () => {
+    const ecosystem = getEcoSystem();
+    const malwareDatabaseUrl =
+      malwareDatabaseUrls[
+        /** @type {keyof typeof malwareDatabaseUrls} */ (ecosystem)
+      ];
+    const response = await fetch(malwareDatabaseUrl);
+    if (!response.ok) {
+      throw new Error(
+        `Error fetching ${ecosystem} malware database: ${response.statusText}`
+      );
+    }
+
+    try {
+      let malwareDatabase = await response.json();
+      return {
+        malwareDatabase: malwareDatabase,
+        version: response.headers.get("etag") || undefined,
+      };
+    } catch (/** @type {any} */ error) {
+      throw new Error(`Error parsing malware database: ${error.message}`);
+    }
+  }, numberOfAttempts);
 }
 
 /**
  * @returns {Promise<string | undefined>}
  */
 export async function fetchMalwareDatabaseVersion() {
-  const ecosystem = getEcoSystem();
-  const malwareDatabaseUrl = malwareDatabaseUrls[/** @type {keyof typeof malwareDatabaseUrls} */ (ecosystem)];
-  const response = await fetch(malwareDatabaseUrl, {
-    method: "HEAD",
-  });
+  const numberOfAttempts = 4;
 
-  if (!response.ok) {
-    throw new Error(
-      `Error fetching ${ecosystem} malware database version: ${response.statusText}`
-    );
-  }
-  return response.headers.get("etag") || undefined;
+  return retry(async () => {
+    const ecosystem = getEcoSystem();
+    const malwareDatabaseUrl =
+      malwareDatabaseUrls[
+        /** @type {keyof typeof malwareDatabaseUrls} */ (ecosystem)
+      ];
+    const response = await fetch(malwareDatabaseUrl, {
+      method: "HEAD",
+    });
+
+    if (!response.ok) {
+      throw new Error(
+        `Error fetching ${ecosystem} malware database version: ${response.statusText}`
+      );
+    }
+    return response.headers.get("etag") || undefined;
+  }, numberOfAttempts);
+}
+
+/**
+ * Retries an asynchronous function multiple times until it succeeds or exhausts all attempts.
+ *
+ * @template T
+ * @param {() => Promise<T>} func - The asynchronous function to retry
+ * @param {number} attempts - The number of attempts
+ * @returns {Promise<T>} The return value of the function if successful
+ * @throws {Error} The last error encountered if all retry attempts fail
+ */
+async function retry(func, attempts) {
+  let lastError;
+
+  for (let i = 0; i < attempts; i++) {
+    try {
+      return await func();
+    } catch (error) {
+      ui.writeVerbose(
+        "An error occurred while trying to download the Aikido Malware database",
+        error
+      );
+      lastError = error;
+    }
+
+    if (i < attempts - 1) {
+      // When this is not the last try, back-off exponentially:
+      //  1st attempt - 500ms delay
+      //  2nd attempt - 1000ms delay
+      //  3rd attempt - 2000ms delay
+      //  4th attempt - 4000ms delay
+      //  ...
+      await new Promise((resolve) => setTimeout(resolve, Math.pow(2, i) * 500));
+    }
+  }
+
+  throw lastError;
 }

packages/safe-chain/src/api/aikido.spec.js

@@ -0,0 +1,125 @@
+import { describe, it, mock, beforeEach } from "node:test";
+import assert from "node:assert";
+
+describe("aikido API", async () => {
+  const mockFetch = mock.fn();
+
+  mock.module("make-fetch-happen", {
+    defaultExport: mockFetch,
+  });
+
+  mock.module("../config/settings.js", {
+    namedExports: {
+      getEcoSystem: () => "js",
+      ECOSYSTEM_JS: "js",
+      ECOSYSTEM_PY: "py",
+    },
+  });
+
+  const { fetchMalwareDatabase, fetchMalwareDatabaseVersion } =
+    await import("./aikido.js");
+
+  beforeEach(() => {
+    mockFetch.mock.resetCalls();
+  });
+
+  describe("fetchMalwareDatabase", () => {
+    it("should succeed immediately when fetch succeeds on first try", async () => {
+      const malwareData = [
+        { package_name: "malicious-pkg", version: "1.0.0", reason: "test" },
+      ];
+      mockFetch.mock.mockImplementationOnce(() => ({
+        ok: true,
+        json: async () => malwareData,
+        headers: { get: () => '"etag-123"' },
+      }));
+
+      const result = await fetchMalwareDatabase();
+
+      assert.strictEqual(mockFetch.mock.calls.length, 1);
+      assert.deepStrictEqual(result.malwareDatabase, malwareData);
+      assert.strictEqual(result.version, '"etag-123"');
+    });
+
+    it("should throw error after exhausting all retries", async () => {
+      mockFetch.mock.mockImplementation(() => {
+        throw new Error("Network error");
+      });
+
+      await assert.rejects(() => fetchMalwareDatabase(), {
+        message: "Network error",
+      });
+
+      assert.strictEqual(mockFetch.mock.calls.length, 4);
+    });
+
+    it("should succeed after failing 3 times and succeeding on 4th attempt", async () => {
+      const malwareData = [
+        { package_name: "bad-pkg", version: "2.0.0", reason: "malware" },
+      ];
+      let callCount = 0;
+      mockFetch.mock.mockImplementation(() => {
+        callCount++;
+        if (callCount < 4) {
+          throw new Error("Network error");
+        }
+        return {
+          ok: true,
+          json: async () => malwareData,
+          headers: { get: () => '"etag-456"' },
+        };
+      });
+
+      const result = await fetchMalwareDatabase();
+
+      assert.strictEqual(mockFetch.mock.calls.length, 4);
+      assert.deepStrictEqual(result.malwareDatabase, malwareData);
+      assert.strictEqual(result.version, '"etag-456"');
+    });
+  });
+
+  describe("fetchMalwareDatabaseVersion", () => {
+    it("should succeed immediately when fetch succeeds on first try", async () => {
+      mockFetch.mock.mockImplementationOnce(() => ({
+        ok: true,
+        headers: { get: () => '"version-etag"' },
+      }));
+
+      const result = await fetchMalwareDatabaseVersion();
+
+      assert.strictEqual(mockFetch.mock.calls.length, 1);
+      assert.strictEqual(result, '"version-etag"');
+    });
+
+    it("should throw error after exhausting all retries", async () => {
+      mockFetch.mock.mockImplementation(() => {
+        throw new Error("Connection refused");
+      });
+
+      await assert.rejects(() => fetchMalwareDatabaseVersion(), {
+        message: "Connection refused",
+      });
+
+      assert.strictEqual(mockFetch.mock.calls.length, 4);
+    });
+
+    it("should succeed after failing 3 times and succeeding on 4th attempt", async () => {
+      let callCount = 0;
+      mockFetch.mock.mockImplementation(() => {
+        callCount++;
+        if (callCount < 4) {
+          throw new Error("Timeout");
+        }
+        return {
+          ok: true,
+          headers: { get: () => '"final-etag"' },
+        };
+      });
+
+      const result = await fetchMalwareDatabaseVersion();
+
+      assert.strictEqual(mockFetch.mock.calls.length, 4);
+      assert.strictEqual(result, '"final-etag"');
+    });
+  });
+});