From e29d851cc6c97908c7e149a994f897276f8ae945 Mon Sep 17 00:00:00 2001
From: Maxime Brunet <max@brnt.mx>
Date: Tue, 27 Sep 2022 05:26:14 -0700
Subject: [PATCH] fix(docker): reduce ECR Public max results to 1000 (#17946)

---
 lib/modules/datasource/docker/index.spec.ts | 52 +++++++++++++++++++++
 lib/modules/datasource/docker/index.ts      |  7 ++-
 2 files changed, 58 insertions(+), 1 deletion(-)

diff --git a/lib/modules/datasource/docker/index.spec.ts b/lib/modules/datasource/docker/index.spec.ts
index 6406f6ceddedb7..76332d86c8acc2 100644
--- a/lib/modules/datasource/docker/index.spec.ts
+++ b/lib/modules/datasource/docker/index.spec.ts
@@ -1194,6 +1194,58 @@ describe('modules/datasource/docker/index', () => {
       });
     });
 
+    it('uses lower tag limit for ECR Public deps', async () => {
+      httpMock
+        .scope('https://public.ecr.aws')
+        .get('/v2/amazonlinux/amazonlinux/tags/list?n=1000')
+        .reply(401, '', {
+          'www-authenticate':
+            'Bearer realm="https://public.ecr.aws/token",service="public.ecr.aws",scope="aws"',
+        })
+        .get('/token?service=public.ecr.aws&scope=aws')
+        .reply(200, { token: 'test' });
+      httpMock
+        .scope('https://public.ecr.aws', {
+          reqheaders: {
+            authorization: 'Bearer test',
+          },
+        })
+        // The  tag limit parameter `n` needs to be limited to 1000 for ECR Public
+        // See https://docs.aws.amazon.com/AmazonECRPublic/latest/APIReference/API_DescribeRepositories.html#ecrpublic-DescribeRepositories-request-maxResults
+        .get('/v2/amazonlinux/amazonlinux/tags/list?n=1000')
+        .reply(200, { tags: ['some'] }, {});
+
+      httpMock
+        .scope('https://public.ecr.aws')
+        .get('/v2/')
+        .reply(401, '', {
+          'www-authenticate':
+            'Bearer realm="https://public.ecr.aws/token",service="public.ecr.aws",scope="aws"',
+        })
+        .get(
+          '/token?service=public.ecr.aws&scope=repository:amazonlinux/amazonlinux:pull'
+        )
+        .reply(200, { token: 'test' });
+      httpMock
+        .scope('https://public.ecr.aws', {
+          reqheaders: {
+            authorization: 'Bearer test',
+          },
+        })
+        .get('/v2/amazonlinux/amazonlinux/manifests/some')
+        .reply(200);
+
+      expect(
+        await getPkgReleases({
+          datasource: DockerDatasource.id,
+          depName: 'public.ecr.aws/amazonlinux/amazonlinux',
+        })
+      ).toEqual({
+        registryUrl: 'https://public.ecr.aws',
+        releases: [],
+      });
+    });
+
     describe('when making requests that interact with an ECR proxy', () => {
       it('resolves requests to ECR proxy', async () => {
         httpMock
diff --git a/lib/modules/datasource/docker/index.ts b/lib/modules/datasource/docker/index.ts
index 65a87195e2c28b..d9c5fc7c311c25 100644
--- a/lib/modules/datasource/docker/index.ts
+++ b/lib/modules/datasource/docker/index.ts
@@ -49,6 +49,7 @@ import {
 export const DOCKER_HUB = 'https://index.docker.io';
 
 export const ecrRegex = regEx(/\d+\.dkr\.ecr\.([-a-z0-9]+)\.amazonaws\.com/);
+export const ecrPublicRegex = regEx(/public\.ecr\.aws/);
 
 function isDockerHost(host: string): boolean {
   const regex = regEx(/(?:^|\.)docker\.io$/);
@@ -818,7 +819,11 @@ export class DockerDatasource extends Datasource {
     let tags: string[] = [];
     // AWS ECR limits the maximum number of results to 1000
     // See https://docs.aws.amazon.com/AmazonECR/latest/APIReference/API_DescribeRepositories.html#ECR-DescribeRepositories-request-maxResults
-    const limit = ecrRegex.test(registryHost) ? 1000 : 10000;
+    // See https://docs.aws.amazon.com/AmazonECRPublic/latest/APIReference/API_DescribeRepositories.html#ecrpublic-DescribeRepositories-request-maxResults
+    const limit =
+      ecrRegex.test(registryHost) || ecrPublicRegex.test(registryHost)
+        ? 1000
+        : 10000;
     let url:
       | string
       | null = `${registryHost}/${dockerRepository}/tags/list?n=${limit}`;