tests for the fetch all reply worker

app/workers/activitypub/fetch_all_replies_worker.rb

@@ -21,7 +21,9 @@ def perform(parent_status_id, current_account_id = nil, options = {})
     Rails.logger.debug { "FetchAllRepliesWorker - #{parent_status_id}: Fetching all replies for status: #{@parent_status}" }
 
     uris_to_fetch = get_replies(@parent_status.uri, options)
-    fetched_uris = uris_to_fetch
+    fetched_uris = uris_to_fetch.clone
+    return if uris_to_fetch.nil?
+
     until uris_to_fetch.empty? || fetched_uris.length >= MAX_REPLIES
       next_reply = uris_to_fetch.pop
       next if next_reply.nil?
@@ -40,18 +42,18 @@ def perform(parent_status_id, current_account_id = nil, options = {})
   private
 
   def get_replies(status_uri, options = {})
-    replies_uri = get_replies_uri(status_uri)
-    return if replies_uri.nil?
+    replies_collection_or_uri = get_replies_uri(status_uri)
+    return if replies_collection_or_uri.nil?
 
-    ActivityPub::FetchAllRepliesService.new.call(replies_uri, **options.deep_symbolize_keys)
+    ActivityPub::FetchAllRepliesService.new.call(replies_collection_or_uri, **options.deep_symbolize_keys)
   end
 
   def get_replies_uri(parent_status_uri)
     begin
       json_status = fetch_resource(parent_status_uri, true, @current_account)
-      replies_uri = json_status['replies']
-      Rails.logger.debug { "FetchAllRepliesWorker - #{@parent_status_id}: replies URI was nil" } if replies_uri.nil?
-      replies_uri
+      replies_collection_or_uri = json_status['replies']
+      Rails.logger.debug { "FetchAllRepliesWorker - #{@parent_status_id}: replies URI was nil" } if replies_collection_or_uri.nil?
+      replies_collection_or_uri
     rescue => e
       Rails.logger.error { "FetchAllRepliesWorker - #{@parent_status_id}: Got exception while resolving replies URI: #{e} - #{e.message}" }
       nil

spec/workers/activitypub/fetch_all_replies_worker_spec.rb

@@ -0,0 +1,254 @@
+# frozen_string_literal: true
+
+require 'rails_helper'
+
+RSpec.describe ActivityPub::FetchAllRepliesWorker do
+  subject { described_class.new }
+
+  let(:top_items) do
+    [
+      'http://example.com/self-reply-1',
+      'http://other.com/other-reply-2',
+      'http://example.com/self-reply-3',
+    ]
+  end
+
+  let(:top_items_paged) do
+    [
+      'http://example.com/self-reply-4',
+      'http://other.com/other-reply-5',
+      'http://example.com/self-reply-6',
+    ]
+  end
+
+  let(:nested_items) do
+    [
+      'http://example.com/nested-self-reply-1',
+      'http://other.com/nested-other-reply-2',
+      'http://example.com/nested-self-reply-3',
+    ]
+  end
+
+  let(:nested_items_paged) do
+    [
+      'http://example.com/nested-self-reply-4',
+      'http://other.com/nested-other-reply-5',
+      'http://example.com/nested-self-reply-6',
+    ]
+  end
+
+  let(:all_items) do
+    top_items + top_items_paged + nested_items + nested_items_paged
+  end
+
+  let(:top_note_uri) do
+    'http://example.com/top-post'
+  end
+
+  let(:top_collection_uri) do
+    'http://example.com/top-post/replies'
+  end
+
+  # The reply uri that has the nested replies under it
+  let(:reply_note_uri) do
+    'http://other.com/other-reply-2'
+  end
+
+  # The collection uri of nested replies
+  let(:reply_collection_uri) do
+    'http://other.com/other-reply-2/replies'
+  end
+
+  let(:replies_top) do
+    {
+      '@context': 'https://www.w3.org/ns/activitystreams',
+      id: top_collection_uri,
+      type: 'Collection',
+      items: top_items + top_items_paged,
+    }
+  end
+
+  let(:replies_nested) do
+    {
+      '@context': 'https://www.w3.org/ns/activitystreams',
+      id: reply_collection_uri,
+      type: 'Collection',
+      items: nested_items + nested_items_paged,
+    }
+  end
+
+  # The status resource for the top post
+  let(:top_object) do
+    {
+      '@context': 'https://www.w3.org/ns/activitystreams',
+      id: top_note_uri,
+      type: 'Note',
+      content: 'Lorem ipsum',
+      replies: replies_top,
+      attributedTo: 'https://example.com',
+    }
+  end
+
+  # The status resource that has the uri to the replies collection
+  let(:reply_object) do
+    {
+      '@context': 'https://www.w3.org/ns/activitystreams',
+      id: reply_note_uri,
+      type: 'Note',
+      content: 'Lorem ipsum',
+      replies: replies_nested,
+      attributedTo: 'https://other.com',
+    }
+  end
+
+  let(:empty_object) do
+    {
+      '@context': 'https://www.w3.org/ns/activitystreams',
+      id: 'https://example.com/empty',
+      type: 'Note',
+      content: 'Lorem ipsum',
+      replies: [],
+      attributedTo: 'https://example.com',
+    }
+  end
+
+  let(:account) { Fabricate(:account, domain: 'example.com') }
+  let(:status)  { Fabricate(:status, account: account, uri: top_note_uri) }
+
+  before do
+    allow(FetchReplyWorker).to receive(:push_bulk)
+    all_items.each do |item|
+      next if [top_note_uri, reply_note_uri].include? item
+
+      stub_request(:get, item).to_return(status: 200, body: Oj.dump(empty_object), headers: { 'Content-Type': 'application/activity+json' })
+    end
+  end
+
+  shared_examples 'fetches all replies' do
+    before do
+      stub_request(:get, top_note_uri).to_return(status: 200, body: Oj.dump(top_object), headers: { 'Content-Type': 'application/activity+json' })
+      stub_request(:get, reply_note_uri).to_return(status: 200, body: Oj.dump(reply_object), headers: { 'Content-Type': 'application/activity+json' })
+    end
+
+    it 'fetches statuses recursively' do
+      got_uris = subject.perform(status.id)
+      expect(got_uris).to match_array(all_items)
+    end
+
+    it 'respects the maxium limits set by not recursing after the max is reached' do
+      stub_const('ActivityPub::FetchAllRepliesWorker::MAX_REPLIES', 5)
+      got_uris = subject.perform(status.id)
+      expect(got_uris).to match_array(top_items + top_items_paged)
+    end
+  end
+
+  describe 'perform' do
+    context 'when the payload is a Note with replies as a Collection of inlined replies' do
+      it_behaves_like 'fetches all replies'
+    end
+
+    context 'when the payload is a Note with replies as a URI to a Collection' do
+      let(:top_object) do
+        {
+          '@context': 'https://www.w3.org/ns/activitystreams',
+          id: top_note_uri,
+          type: 'Note',
+          content: 'Lorem ipsum',
+          replies: top_collection_uri,
+          attributedTo: 'https://example.com',
+        }
+      end
+      let(:reply_object) do
+        {
+          '@context': 'https://www.w3.org/ns/activitystreams',
+          id: reply_note_uri,
+          type: 'Note',
+          content: 'Lorem ipsum',
+          replies: reply_collection_uri,
+          attributedTo: 'https://other.com',
+        }
+      end
+
+      before do
+        stub_request(:get, top_collection_uri).to_return(status: 200, body: Oj.dump(replies_top), headers: { 'Content-Type': 'application/activity+json' })
+        stub_request(:get, reply_collection_uri).to_return(status: 200, body: Oj.dump(replies_nested), headers: { 'Content-Type': 'application/activity+json' })
+      end
+
+      it_behaves_like 'fetches all replies'
+    end
+
+    context 'when the payload is a Note with replies as a paginated collection' do
+      let(:top_page_2_uri) do
+        "#{top_collection_uri}/2"
+      end
+
+      let(:reply_page_2_uri) do
+        "#{reply_collection_uri}/2"
+      end
+
+      let(:top_object) do
+        {
+          '@context': 'https://www.w3.org/ns/activitystreams',
+          id: top_note_uri,
+          type: 'Note',
+          content: 'Lorem ipsum',
+          replies: {
+            type: 'Collection',
+            id: top_collection_uri,
+            first: {
+              type: 'CollectionPage',
+              partOf: top_collection_uri,
+              items: top_items,
+              next: top_page_2_uri,
+            },
+          },
+          attributedTo: 'https://example.com',
+        }
+      end
+      let(:reply_object) do
+        {
+          '@context': 'https://www.w3.org/ns/activitystreams',
+          id: reply_note_uri,
+          type: 'Note',
+          content: 'Lorem ipsum',
+          replies: {
+            type: 'Collection',
+            id: reply_collection_uri,
+            first: {
+              type: 'CollectionPage',
+              partOf: reply_collection_uri,
+              items: nested_items,
+              next: reply_page_2_uri,
+            },
+          },
+          attributedTo: 'https://other.com',
+        }
+      end
+
+      let(:top_page_two) do
+        {
+          type: 'CollectionPage',
+          id: top_page_2_uri,
+          partOf: top_collection_uri,
+          items: top_items_paged,
+        }
+      end
+
+      let(:reply_page_two) do
+        {
+          type: 'CollectionPage',
+          id: reply_page_2_uri,
+          partOf: reply_collection_uri,
+          items: nested_items_paged,
+        }
+      end
+
+      before do
+        stub_request(:get, top_page_2_uri).to_return(status: 200, body: Oj.dump(top_page_two), headers: { 'Content-Type': 'application/activity+json' })
+        stub_request(:get, reply_page_2_uri).to_return(status: 200, body: Oj.dump(reply_page_two), headers: { 'Content-Type': 'application/activity+json' })
+      end
+
+      it_behaves_like 'fetches all replies'
+    end
+  end
+end