Define common helper for describe pagination params in api

changelogs/unreleased/23532-define-common-helper-for-describe-pagination-params-in-api.yml

+---
+title: Define common helper for describe pagination params in api
+merge_request: 7646
+author: Semyon Pupkov

lib/api/broadcast_messages.rb

 module API
   class BroadcastMessages < Grape::API
+    include PaginationParams
+
     before { authenticate! }
     before { authenticated_as_admin! }
@@ -15,8 +17,7 @@ module API
         success Entities::BroadcastMessage
       end
       params do
-        optional :page,     type: Integer, desc: 'Current page number'
-        optional :per_page, type: Integer, desc: 'Number of messages per page'
+        use :pagination
       end
       get do
         messages = BroadcastMessage.all

lib/api/commits.rb

@@ -3,6 +3,8 @@ require 'mime/types'
 module API
   # Projects commits API
   class Commits < Grape::API
+    include PaginationParams
+
     before { authenticate! }
     before { authorize! :download_code, user_project }
@@ -107,9 +109,8 @@ module API
         failure [[404, 'Not Found']]
       end
       params do
+        use :pagination
         requires :sha, type: String, desc: 'A commit sha, or the name of a branch or tag'
-        optional :per_page, type: Integer, desc: 'The amount of items per page for paginaion'
-        optional :page, type: Integer, desc: 'The page number for pagination'
       end
       get ':id/repository/commits/:sha/comments' do
         commit = user_project.commit(params[:sha])

lib/api/deployments.rb

 module API
   # Deployments RESTfull API endpoints
   class Deployments < Grape::API
+    include PaginationParams
+
     before { authenticate! }
     params do
@@ -12,8 +14,7 @@ module API
         success Entities::Deployment
       end
       params do
-        optional :page,     type: Integer, desc: 'Page number of the current request'
-        optional :per_page, type: Integer, desc: 'Number of items per page'
+        use :pagination
       end
       get ':id/deployments' do
         authorize! :read_deployment, user_project

lib/api/environments.rb

 module API
   # Environments RESTfull API endpoints
   class Environments < Grape::API
+    include PaginationParams
+
     before { authenticate! }
     params do
@@ -12,8 +14,7 @@ module API
         success Entities::Environment
       end
       params do
-        optional :page,     type: Integer, desc: 'Page number of the current request'
-        optional :per_page, type: Integer, desc: 'Number of items per page'
+        use :pagination
       end
       get ':id/environments' do
         authorize! :read_environment, user_project

lib/api/pagination_params.rb

+module API
+  # Concern for declare pagination params.
+  #
+  # @example
+  #   class CustomApiResource < Grape::API
+  #     include PaginationParams
+  #
+  #     params do
+  #       use :pagination
+  #     end
+  #   end
+  module PaginationParams
+    extend ActiveSupport::Concern
+
+    included do
+      helpers do
+        params :pagination do
+          optional :page, type: Integer, desc: 'Current page number'
+          optional :per_page, type: Integer, desc: 'Number of items per page'
+        end
+      end
+    end
+  end
+end

lib/api/pipelines.rb

 module API
   class Pipelines < Grape::API
+    include PaginationParams
+
     before { authenticate! }
     params do
@@ -11,8 +13,7 @@ module API
         success Entities::Pipeline
       end
       params do
-        optional :page,     type: Integer, desc: 'Page number of the current request'
-        optional :per_page, type: Integer, desc: 'Number of items per page'
+        use :pagination
         optional :scope,    type: String, values: ['running', 'branches', 'tags'],
                             desc: 'Either running, branches, or tags'
       end

lib/api/variables.rb

 module API
   # Projects variables API
   class Variables < Grape::API
+    include PaginationParams
+
     before { authenticate! }
     before { authorize! :admin_build, user_project }
@@ -13,8 +15,7 @@ module API
         success Entities::Variable
       end
       params do
-        optional :page, type: Integer, desc: 'The page number for pagination'
-        optional :per_page, type: Integer, desc: 'The value of items per page to show'
+        use :pagination
       end
       get ':id/variables' do
         variables = user_project.variables