Use ILIKE/LIKE for searching CI runners

app/models/ci/runner.rb

@@ -46,9 +46,23 @@ module Ci
 
     acts_as_taggable
 
+    # Searches for runners matching the given query.
+    #
+    # This method uses ILIKE on PostgreSQL and LIKE on MySQL.
+    #
+    # This method performs a *partial* match on tokens, thus a query for "a"
+    # will match any runner where the token contains the letter "a". As a result
+    # you should *not* use this method for non-admin purposes as otherwise users
+    # might be able to query a list of all runners.
+    #
+    # query - The search query as a String
+    #
+    # Returns an ActiveRecord::Relation.
     def self.search(query)
-      where('LOWER(ci_runners.token) LIKE :query OR LOWER(ci_runners.description) like :query',
-            query: "%#{query.try(:downcase)}%")
+      t = Ci::Runner.arel_table
+      pattern = "%#{query}%"
+
+      where(t[:token].matches(pattern).or(t[:description].matches(pattern)))
     end
 
     def set_default_values

spec/models/ci/runner_spec.rb

@@ -132,4 +132,32 @@ describe Ci::Runner, models: true do
       expect(runner.belongs_to_one_project?).to be_truthy
     end
   end
+
+  describe '#search' do
+    let(:runner) { create(:ci_runner, token: '123abc') }
+
+    it 'returns runners with a matching token' do
+      expect(described_class.search(runner.token)).to eq([runner])
+    end
+
+    it 'returns runners with a partially matching token' do
+      expect(described_class.search(runner.token[0..2])).to eq([runner])
+    end
+
+    it 'returns runners with a matching token regardless of the casing' do
+      expect(described_class.search(runner.token.upcase)).to eq([runner])
+    end
+
+    it 'returns runners with a matching description' do
+      expect(described_class.search(runner.description)).to eq([runner])
+    end
+
+    it 'returns runners with a partially matching description' do
+      expect(described_class.search(runner.description[0..2])).to eq([runner])
+    end
+
+    it 'returns runners with a matching description regardless of the casing' do
+      expect(described_class.search(runner.description.upcase)).to eq([runner])
+    end
+  end
 end