Expose snippets_size in ProjectStatistics Entity

This commit add the snippets_size field to
the ProjectStatistics Entity.

changelogs/unreleased/fj-223705-add-snippets-size-to-project-statistics-entity.yml

+---
+title: Expose snippets_size in ProjectStatistics Entity
+merge_request: 35316
+author:
+type: changed

doc/api/projects.md

@@ -175,7 +175,8 @@ When the user is authenticated and `simple` is not set this returns something li
       "wiki_size" : 0,
       "lfs_objects_size": 0,
       "job_artifacts_size": 0,
-      "packages_size": 0
+      "packages_size": 0,
+      "snippets_size": 0
     },
     "_links": {
       "self": "http://example.com/api/v4/projects",
@@ -277,7 +278,8 @@ When the user is authenticated and `simple` is not set this returns something li
       "wiki_size" : 0,
       "lfs_objects_size": 0,
       "job_artifacts_size": 0,
-      "packages_size": 0
+      "packages_size": 0,
+      "snippets_size": 0
     },
     "_links": {
       "self": "http://example.com/api/v4/projects",
@@ -426,7 +428,8 @@ This endpoint supports [keyset pagination](README.md#keyset-based-pagination) fo
       "wiki_size" : 0,
       "lfs_objects_size": 0,
       "job_artifacts_size": 0,
-      "packages_size": 0
+      "packages_size": 0,
+      "snippets_size": 0
     },
     "_links": {
       "self": "http://example.com/api/v4/projects",
@@ -528,7 +531,8 @@ This endpoint supports [keyset pagination](README.md#keyset-based-pagination) fo
       "wiki_size" : 0,
       "lfs_objects_size": 0,
       "job_artifacts_size": 0,
-      "packages_size": 0
+      "packages_size": 0,
+      "snippets_size": 0
     },
     "_links": {
       "self": "http://example.com/api/v4/projects",
@@ -899,7 +903,8 @@ GET /projects/:id
     "wiki_size" : 0,
     "lfs_objects_size": 0,
     "job_artifacts_size": 0,
-    "packages_size": 0
+    "packages_size": 0,
+    "snippets_size": 0
   },
   "_links": {
     "self": "http://example.com/api/v4/projects",

lib/api/entities/project_statistics.rb

@@ -9,6 +9,7 @@ module API
       expose :wiki_size
       expose :lfs_objects_size
       expose :build_artifacts_size, as: :job_artifacts_size
+      expose :snippets_size
     end
   end
 end

spec/requests/api/projects_spec.rb

@@ -254,7 +254,10 @@ RSpec.describe API::Projects do
         expect(response).to have_gitlab_http_status(:ok)
         expect(response).to include_pagination_headers
         expect(json_response).to be_an Array
-        expect(json_response.first).to include 'statistics'
+
+        statistics = json_response.first['statistics']
+        expect(statistics).to be_present
+        expect(statistics).to include('commit_count', 'storage_size', 'repository_size', 'wiki_size', 'lfs_objects_size', 'job_artifacts_size', 'snippets_size')
       end
 
       it "does not include license by default" do