Support [Feedz] response with multiple pages without items (#7476)

* Support Feedz response with multiple pages without items

* Parallelize fetches from Feedz when getting multiple pages

* Simplify schema management

* Retrun early if we don't need to fetch any more pages

Co-authored-by: repo-ranger[bot] <39074581+repo-ranger[bot]@users.noreply.github.com>

services/feedz/feedz.service.js

@@ -7,22 +7,23 @@ import {
   selectVersion,
 } from '../nuget/nuget-helpers.js'
 
-const schema = Joi.object({
+const singlePageSchema = Joi.object({
+  '@id': Joi.string().required(),
   items: Joi.array()
     .items(
       Joi.object({
-        items: Joi.array().items(
-          Joi.object({
-            catalogEntry: Joi.object({
-              version: Joi.string().required(),
-            }).required(),
-          })
-        ),
-      }).required()
+        catalogEntry: Joi.object({
+          version: Joi.string().required(),
+        }).required(),
+      })
     )
     .default([]),
 }).required()
 
+const packageSchema = Joi.object({
+  items: Joi.array().items(singlePageSchema).default([]),
+}).required()
+
 class FeedzVersionService extends BaseJsonService {
   static category = 'version'
 
@@ -72,7 +73,7 @@ class FeedzVersionService extends BaseJsonService {
       'RegistrationsBaseUrl'
     )
     return await this._requestJson({
-      schema,
+      schema: packageSchema,
       url: `${registrationsBaseUrl}${packageName}/index.json`,
       errorMessages: {
         404: 'repository or package not found',
@@ -80,6 +81,25 @@ class FeedzVersionService extends BaseJsonService {
     })
   }
 
+  async fetchItems({ json }) {
+    if (json.items.length === 0 || json.items.some(i => i.catalogEntry)) {
+      return json
+    } else {
+      const items = await Promise.all(
+        json.items.map(i =>
+          this._requestJson({
+            schema: singlePageSchema,
+            url: i['@id'],
+            errorMessages: {
+              404: 'repository or package not found',
+            },
+          })
+        )
+      )
+      return { items }
+    }
+  }
+
   transform({ json, includePrereleases }) {
     const versions = json.items.flatMap(tl =>
       tl.items.map(i => stripBuildMetadata(i.catalogEntry.version))
@@ -95,7 +115,8 @@ class FeedzVersionService extends BaseJsonService {
     const includePrereleases = which === 'vpre'
     const baseUrl = this.apiUrl({ organization, repository })
     const json = await this.fetch({ baseUrl, packageName })
-    const version = this.transform({ json, includePrereleases })
+    const fetchedJson = await this.fetchItems({ json })
+    const version = this.transform({ json: fetchedJson, includePrereleases })
     return this.constructor.render({
       version,
       feed: FeedzVersionService.defaultBadgeData.label,

services/feedz/feedz.tester.js

@@ -11,6 +11,8 @@ export const t = new ServiceTester({
 //  - Shields.TestPackage: 0.0.1, 0.1.0-pre, 1.0.0
 //  - Shields.TestPreOnly: 0.1.0-pre
 //  - Shields.MultiPage: 0.1.0-0.1.100 plus 1.0.0 but the response has multiple top-level `items`
+//  - Shields.MultiPageNoItems: 0.0.0-0.0.256 plus 1.0.0 but the response has multiple top-level
+//    `items` without `catalogEntries`
 // The source code of these packages is here: https://github.com/jakubfijalkowski/shields-test-packages
 
 // version
@@ -46,6 +48,14 @@ t.create('multi-page')
     color: 'blue',
   })
 
+t.create('multi-page-no-items')
+  .get('/feedz/v/shieldstests/public/Shields.MultiPageNoItems.json')
+  .expectBadge({
+    label: 'feedz',
+    message: 'v1.0.0',
+    color: 'blue',
+  })
+
 t.create('repository (not found)')
   .get('/feedz/v/foo/bar/not-a-real-package.json')
   .expectBadge({ label: 'feedz', message: 'repository or package not found' })