feat(rubygems): fallback to info when version fails

lib/datasource/rubygems/get.ts

@@ -50,23 +50,46 @@ export async function getDependency(
     return null;
   }
 
-  const versions = (await fetch(dependency, registry, VERSIONS_PATH)) || [];
+  let versions = [];
+  let releases = [];
+  try {
+    versions = await fetch(dependency, registry, VERSIONS_PATH);
+  } catch (err) {
+    if (err.statusCode === 400 || err.statusCode === 404) {
+      logger.debug(
+        { registry },
+        'versions endpoint returns error - falling back to info endpoint'
+      );
+    } else {
+      throw err;
+    }
+  }
 
-  const releases = versions.map(
-    ({
-      number: version,
-      platform: rubyPlatform,
-      created_at: releaseTimestamp,
-      rubygems_version: rubygemsVersion,
-      ruby_version: rubyVersion,
-    }) => ({
-      version,
-      rubyPlatform,
-      releaseTimestamp,
-      rubygemsVersion,
-      rubyVersion,
-    })
-  );
+  if (versions.length === 0 && info.version) {
+    logger.warn('falling back to the version from the info endpoint');
+    releases = [
+      {
+        version: info.version,
+        rubyPlatform: info.platform,
+      },
+    ];
+  } else {
+    releases = versions.map(
+      ({
+        number: version,
+        platform: rubyPlatform,
+        created_at: releaseTimestamp,
+        rubygems_version: rubygemsVersion,
+        ruby_version: rubyVersion,
+      }) => ({
+        version,
+        rubyPlatform,
+        releaseTimestamp,
+        rubygemsVersion,
+        rubyVersion,
+      })
+    );
+  }
 
   return {
     releases,

lib/datasource/rubygems/index.spec.ts

@@ -167,5 +167,25 @@ describe('datasource/rubygems', () => {
       expect(await getPkgReleases(params)).toBeNull();
       expect(httpMock.getTrace()).toMatchSnapshot();
     });
+    it('falls back to info when version request fails', async () => {
+      httpMock
+        .scope('https://thirdparty.com/')
+        .get('/api/v1/gems/rails.json')
+        .reply(200, railsInfo)
+        .get('/api/v1/versions/rails.json')
+        .reply(400, {});
+      const res = await getPkgReleases(params);
+      expect(res.releases).toHaveLength(1);
+      expect(res.releases[0].version).toBe(railsInfo.version);
+    });
+    it('errors when version request fails with anything other than 400 or 404', async () => {
+      httpMock
+        .scope('https://thirdparty.com/')
+        .get('/api/v1/gems/rails.json')
+        .reply(200, railsInfo)
+        .get('/api/v1/versions/rails.json')
+        .reply(500, {});
+      expect(await getPkgReleases(params)).toBeNull();
+    });
   });
 });

package.json

@@ -96,7 +96,8 @@
     "Viral Ruparel <[email protected]>",
     "Vladimir Starkov <[email protected]>",
     "Mikhail Yakushin <[email protected]>",
-    "Sebastian Poxhofer <[email protected]>"
+    "Sebastian Poxhofer <[email protected]>",
+    "Henry Sachs <[email protected]>"
   ],
   "license": "AGPL-3.0",
   "bugs": {