Fix regex for key name format

lib/gitlab/redis/hll.rb

@@ -2,9 +2,9 @@
 
 module Gitlab
   module Redis
-    KeyFormatError = Class.new(StandardError)
-
     class HLL
+      KeyFormatError = Class.new(StandardError)
+
       def self.count(params)
         self.new.count(params)
       end
@@ -20,7 +20,7 @@ module Gitlab
       end
 
       def add(key:, value:, expiry:)
-        unless %r{\A.*\{.*\}.*\z}.match?(key)
+        unless %r{\A(\w|-|:)*\{\w*\}(\w|-|:)*\z}.match?(key)
           raise KeyFormatError.new("Invalid key format. #{key} key should have changeable parts in curly braces. See https://docs.gitlab.com/ee/development/redis.html#multi-key-commands")
         end
 

spec/lib/gitlab/redis/hll_spec.rb

@@ -5,13 +5,15 @@ require 'spec_helper'
 RSpec.describe Gitlab::Redis::HLL, :clean_gitlab_redis_shared_state do
   describe '.add' do
     it 'raise an error when using an invalid key format' do
-      expect { described_class.add(key: 'test', value: 1, expiry: 1.day) }.to raise_error(Gitlab::Redis::KeyFormatError)
-      expect { described_class.add(key: 'test-{metric', value: 1, expiry: 1.day) }.to raise_error(Gitlab::Redis::KeyFormatError)
+      expect { described_class.add(key: 'test', value: 1, expiry: 1.day) }.to raise_error(Gitlab::Redis::HLL::KeyFormatError)
+      expect { described_class.add(key: 'test-{metric', value: 1, expiry: 1.day) }.to raise_error(Gitlab::Redis::HLL::KeyFormatError)
+      expect { described_class.add(key: 'test-{metric}}', value: 1, expiry: 1.day) }.to raise_error(Gitlab::Redis::HLL::KeyFormatError)
     end
 
     it "doesn't raise error when having correct format" do
       expect { described_class.add(key: 'test-{metric}', value: 1, expiry: 1.day) }.not_to raise_error
       expect { described_class.add(key: 'test-{metric}-1', value: 1, expiry: 1.day) }.not_to raise_error
+      expect { described_class.add(key: 'test:{metric}-1', value: 1, expiry: 1.day) }.not_to raise_error
     end
   end
 end