Don't allow a default for reactive_cache_work_type

If we force this to be set explicitly, it's more likely to be correct.

app/models/clusters/platforms/kubernetes.rb

@@ -11,6 +11,7 @@ module Clusters
       RESERVED_NAMESPACES = %w(gitlab-managed-apps).freeze
 
       self.table_name = 'cluster_platforms_kubernetes'
+      self.reactive_cache_work_type = :external_dependency
 
       belongs_to :cluster, inverse_of: :platform_kubernetes, class_name: 'Clusters::Cluster'
 

app/models/concerns/reactive_caching.rb

@@ -9,7 +9,7 @@ module ReactiveCaching
   ExceededReactiveCacheLimit = Class.new(StandardError)
 
   WORK_TYPE = {
-    default: ReactiveCachingWorker,
+    no_dependency: ReactiveCachingWorker,
     external_dependency: ExternalServiceReactiveCachingWorker
   }.freeze
 
@@ -30,7 +30,6 @@ module ReactiveCaching
     self.reactive_cache_refresh_interval = 1.minute
     self.reactive_cache_lifetime = 10.minutes
     self.reactive_cache_hard_limit = nil # this value should be set in megabytes. E.g: 1.megabyte
-    self.reactive_cache_work_type = :default
     self.reactive_cache_worker_finder = ->(id, *_args) do
       find_by(primary_key => id)
     end

app/models/concerns/reactive_service.rb

@@ -8,5 +8,6 @@ module ReactiveService
 
     # Default cache key: class name + project_id
     self.reactive_cache_key = ->(service) { [service.class.model_name.singular, service.project_id] }
+    self.reactive_cache_work_type = :external_dependency
   end
 end

app/models/merge_request.rb

@@ -30,6 +30,7 @@ class MergeRequest < ApplicationRecord
   self.reactive_cache_key = ->(model) { [model.project.id, model.iid] }
   self.reactive_cache_refresh_interval = 10.minutes
   self.reactive_cache_lifetime = 10.minutes
+  self.reactive_cache_work_type = :no_dependency
 
   SORTING_PREFERENCE_FIELD = :merge_requests_sort
 

app/services/pod_logs/base_service.rb

@@ -10,6 +10,8 @@ module PodLogs
     CACHE_KEY_GET_POD_LOG = 'get_pod_log'
     K8S_NAME_MAX_LENGTH = 253
 
+    self.reactive_cache_work_type = :external_dependency
+
     def id
       cluster.id
     end

app/services/pod_logs/elasticsearch_service.rb

@@ -11,7 +11,6 @@ module PodLogs
           :pod_logs,
           :filter_return_keys
 
-    self.reactive_cache_work_type = :external_dependency
     self.reactive_cache_worker_finder = ->(id, _cache_key, namespace, params) { new(::Clusters::Cluster.find(id), namespace, params: params) }
 
     private

app/services/pod_logs/kubernetes_service.rb

@@ -17,7 +17,6 @@ module PodLogs
           :split_logs,
           :filter_return_keys
 
-    self.reactive_cache_work_type = :external_dependency
     self.reactive_cache_worker_finder = ->(id, _cache_key, namespace, params) { new(::Clusters::Cluster.find(id), namespace, params: params) }
 
     private

doc/development/reactive_caching.md

@@ -85,9 +85,7 @@ The ReactiveCaching concern can be used in models as well as `project_services`
 
 1. Implement the `calculate_reactive_cache` method in your model/service.
 1. Call `with_reactive_cache` in your model/service where the cached value is needed.
-1. If the `calculate_reactive_cache` method above submits requests to external services
-(e.g. Prometheus, K8s), make sure to change the
-[`reactive_cache_work_type` accordingly](#selfreactive_cache_work_type).
+1. Set the [`reactive_cache_work_type` accordingly](#selfreactive_cache_work_type).
 
 ### In controllers
 
@@ -252,7 +250,7 @@ self.reactive_cache_hard_limit = 5.megabytes
 - This is the type of work performed by the `calculate_reactive_cache` method. Based on this attribute,
 it's able to pick the right worker to process the caching job. Make sure to
 set it as `:external_dependency` if the work performs any external request
-(e.g. Kubernetes, Sentry).
+(e.g. Kubernetes, Sentry); otherwise set it to `:no_dependency`.
 
 #### `self.reactive_cache_worker_finder`
 

spec/models/concerns/reactive_caching_spec.rb

@@ -14,6 +14,7 @@ RSpec.describe ReactiveCaching, :use_clean_rails_memory_store_caching do
 
       self.reactive_cache_lifetime = 5.minutes
       self.reactive_cache_refresh_interval = 15.seconds
+      self.reactive_cache_work_type = :no_dependency
 
       attr_reader :id
 
@@ -372,4 +373,14 @@ RSpec.describe ReactiveCaching, :use_clean_rails_memory_store_caching do
     it { expect(subject.reactive_cache_hard_limit).to be_nil }
     it { expect(subject.reactive_cache_worker_finder).to respond_to(:call) }
   end
+
+  describe 'classes including this concern' do
+    it 'sets reactive_cache_work_type' do
+      classes = ObjectSpace.each_object(Class).select do |klass|
+        klass < described_class && klass.name
+      end
+
+      expect(classes).to all(have_attributes(reactive_cache_work_type: be_in(described_class::WORK_TYPE.keys)))
+    end
+  end
 end