more specs

lib/karafka/web/ui/models/message.rb

@@ -215,6 +215,7 @@ def per_page
             # @param start_offset [Integer] offset of the first message (lowest) that we received
             # @param count [Integer] how many messages we wanted - we need that to fill spots to
             #   have exactly the number that was  requested and not more
+            # @param high_offset [Integer] high watermark offset
             # @return [Array<Karafka::Messages::Message, Integer>] array with gaps filled with the
             #   missing offset
             def fill_compacted(messages, partition_id, start_offset, count, high_offset)

spec/lib/karafka/web/ui/models/message_spec.rb

@@ -1,5 +1,9 @@
 # frozen_string_literal: true
 
+require 'karafka/pro/iterator'
+require 'karafka/pro/iterator/expander'
+require 'karafka/pro/iterator/tpl_builder'
+
 RSpec.describe_current do
   let(:topic) { create_topic }
   let(:partition) { 0 }
@@ -190,9 +194,78 @@
         expect(page[2]).to eq(25)
       end
     end
+
+    context 'when there is a lot of data and we want the most recent page (-1)' do
+      before { produce_many(topic, (0..99).map(&:to_s)) }
+
+      let(:start_offset) { -1 }
+
+      it 'expect to return it in order' do
+        expect(page[0]).to eq(false)
+        expect(page[1].map(&:offset)).to eq((75..99).to_a.reverse)
+        expect(page[2]).to eq(50)
+      end
+    end
   end
 
   describe '#topic_page' do
+    subject(:result) { described_class.topic_page(topic, partitions_ids, page) }
+
+    let(:topic) { create_topic(partitions: 4) }
+    let(:partitions_ids) { (0..3).to_a }
+    let(:page) { 1 }
+
+    context 'when there is no data in any of the partitions' do
+      it { expect(result).to eq([[], false]) }
+    end
+
+    context 'when we try to reach beyond first page on empty' do
+      let(:page) { 2 }
+
+      it { expect(result).to eq([[], false]) }
+    end
 
+    context 'when there is some data in the first partition only' do
+      before { produce_many(topic, (0..3).map(&:to_s), partition: 0) }
+
+      it 'expect to return this data' do
+        expect(result[0].map(&:offset)).to eq([3, 2, 1, 0])
+        expect(result[1]).to eq(false)
+      end
+    end
+
+    context 'when there is some data in each of the partitions' do
+      before do
+        produce(topic, '0', partition: 0)
+        produce(topic, '1', partition: 1)
+        produce(topic, '2', partition: 2)
+        produce(topic, '3', partition: 3)
+      end
+
+      it 'expect to return this data' do
+        expect(result[0].map(&:offset)).to eq([0, 0, 0, 0])
+        expect(result[0].map(&:partition)).to eq([0, 1, 2, 3])
+        expect(result[1]).to eq(false)
+      end
+    end
+
+    context 'when there are more partitions than space on the first page but data only beyond' do
+      let(:topic) { create_topic(partitions: 100) }
+      let(:partitions_ids) { (25..29).to_a }
+
+      before do
+        produce(topic, '0', partition: 24)
+        produce(topic, '0', partition: 25)
+        produce(topic, '1', partition: 26)
+        produce(topic, '2', partition: 27)
+        produce(topic, '3', partition: 28)
+      end
+
+      it 'expect to fetch from partitions we want' do
+        expect(result[0].map(&:offset)).to eq([0, 0, 0, 0])
+        expect(result[0].map(&:partition)).to eq((25..28).to_a)
+        expect(result[1]).to eq(false)
+      end
+    end
   end
 end

spec/lib/karafka/web/ui/models/partition_spec.rb

@@ -0,0 +1,19 @@
+# frozen_string_literal: true
+
+RSpec.describe_current do
+  subject(:partition) { described_class.new(data) }
+
+  let(:data) { {} }
+
+  describe '#lag' do
+    context 'when not available' do
+      it { expect(partition.lag).to eq(-1) }
+    end
+
+    context 'when available' do
+      let(:data) { { lag: 100 } }
+
+      it { expect(partition.lag).to eq(100) }
+    end
+  end
+end

spec/spec_helper.rb

@@ -62,7 +62,7 @@ class App
 # @param topic_name [String] topic name. Default will generate automatically
 # @param partitions [Integer] number of partitions (one by default)
 # @return [String] generated topic name
-def create_topic(topic_name = SecureRandom.uuid, partitions = 1)
+def create_topic(topic_name: SecureRandom.uuid, partitions: 1)
   Karafka::Admin.create_topic(topic_name, partitions, 1)
   topic_name
 end