add spec and project snippet user agent details endpoint

doc/api/project_snippets.md

@@ -149,4 +149,5 @@ Example response:
   "akismet_submitted": false
 }
 ```
+
 [ce-[ce-29508]: https://gitlab.com/gitlab-org/gitlab-ce/issues/29508]: https://gitlab.com/gitlab-org/gitlab-ce/issues/29508

doc/api/snippets.md

@@ -264,4 +264,5 @@ Example response:
   "akismet_submitted": false
 }
 ```
+
 [ce-[ce-29508]: https://gitlab.com/gitlab-org/gitlab-ce/issues/29508]: https://gitlab.com/gitlab-org/gitlab-ce/issues/29508

lib/api/project_snippets.rb

@@ -131,6 +131,22 @@ module API
         content_type 'text/plain'
         present snippet.content
       end
+
+      desc 'Get the user agent details for a project snippet' do
+        success Entities::UserAgentDetail
+      end
+      params do
+        requires :snippet_id, type: Integer, desc: 'The ID of a project snippet'
+      end
+      get ":id/snippets/:snippet_id/user_agent_detail" do
+        authenticated_as_admin!
+
+        snippet = Snippet.find_by!(id: params[:id])
+
+        return not_found!('UserAgentDetail') unless snippet.user_agent_detail
+
+        present snippet.user_agent_detail, with: Entities::UserAgentDetail
+      end
     end
   end
 end

spec/requests/api/project_snippets_spec.rb

@@ -242,4 +242,25 @@ describe API::ProjectSnippets do
       expect(json_response['message']).to eq('404 Snippet Not Found')
     end
   end
+
+  describe "GET /projects/:project_id/snippets/:id/user_agent_detail" do
+    let(:admin) { create(:admin) }
+    let(:snippet) { create(:project_snippet, author: admin) }
+    let!(:user_agent_detail) { create(:user_agent_detail, subject: snippet) }
+
+    it 'exposes known attributes' do
+      get api("/projects/#{snippet.project.id}/snippets/#{snippet.id}/user_agent_detail", admin)
+
+      expect(response).to have_http_status(200)
+      expect(json_response['user_agent']).to eq(user_agent_detail.user_agent)
+      expect(json_response['ip_address']).to eq(user_agent_detail.ip_address)
+      expect(json_response['akismet_submitted']).to eq(user_agent_detail.submitted)
+    end
+
+    it "returns unautorized for non-admin users" do
+      get api("/projects/#{snippet.project.id}/snippets/#{snippet.id}/user_agent_detail", user)
+
+      expect(response).to have_http_status(403)
+    end
+  end
 end