Merge branch '4269-public-api' into 'master'

Allow public access to some Project API endpoints

## What does this MR do?

This opens up a few endpoints in the Project API:

- `GET /projects/visible` (returns public projects only)
- `GET /projects/search/:query` (returns results only for public projects)
- `GET /projects/:id` (only if the project is public)
- `GET /projects/:id/events` (only if the project is public)
- `GET /projects/:id/users` (only if the project is public)

## Are there points in the code the reviewer needs to double check?

I've chosen to explicitly add `authenticate!` to GET methods that still need a current user.

## Does this MR meet the acceptance criteria?

- [x] [Changelog entry](https://docs.gitlab.com/ce/development/changelog.html) added
- [ ] [Documentation created/updated](https://gitlab.com/gitlab-org/gitlab-ce/blob/master/doc/development/doc_styleguide.md)
- [x] API support added
- Tests
  - [x] Added for this feature/bug
  - [ ] All builds are passing

Part of #4269

See merge request !7843

changelogs/unreleased/4269-public-api.yml

+---
+title: Allow public access to some Project API endpoints
+merge_request: 7843
+author:

lib/api/helpers.rb

@@ -141,6 +141,10 @@ module API
       unauthorized! unless current_user
     end
 
+    def authenticate_non_get!
+      authenticate! unless %w[GET HEAD].include?(route.route_method)
+    end
+
     def authenticate_by_gitlab_shell_token!
       input = params['secret_token'].try(:chomp)
       unless Devise.secure_compare(secret_token, input)
@@ -149,6 +153,7 @@ module API
     end
 
     def authenticated_as_admin!
+      authenticate!
       forbidden! unless current_user.is_admin?
     end
 

lib/api/projects.rb

@@ -3,7 +3,7 @@ module API
   class Projects < Grape::API
     include PaginationParams
 
-    before { authenticate! }
+    before { authenticate_non_get! }
 
     helpers do
       params :optional_params do
@@ -61,7 +61,7 @@ module API
         end
       end
 
-      desc 'Get a projects list for authenticated user' do
+      desc 'Get a list of visible projects for authenticated user' do
         success Entities::BasicProjectDetails
       end
       params do
@@ -70,15 +70,15 @@ module API
         use :filter_params
         use :pagination
       end
-      get do
-        projects = current_user.authorized_projects
+      get '/visible' do
+        projects = ProjectsFinder.new.execute(current_user)
         projects = filter_projects(projects)
-        entity = params[:simple] ? Entities::BasicProjectDetails : Entities::ProjectWithAccess
+        entity = params[:simple] || !current_user ? Entities::BasicProjectDetails : Entities::ProjectWithAccess
 
         present paginate(projects), with: entity, user: current_user
       end
 
-      desc 'Get a list of visible projects for authenticated user' do
+      desc 'Get a projects list for authenticated user' do
         success Entities::BasicProjectDetails
       end
       params do
@@ -87,8 +87,10 @@ module API
         use :filter_params
         use :pagination
       end
-      get '/visible' do
-        projects = ProjectsFinder.new.execute(current_user)
+      get do
+        authenticate!
+
+        projects = current_user.authorized_projects
         projects = filter_projects(projects)
         entity = params[:simple] ? Entities::BasicProjectDetails : Entities::ProjectWithAccess
 
@@ -103,6 +105,8 @@ module API
         use :pagination
       end
       get '/owned' do
+        authenticate!
+
         projects = current_user.owned_projects
         projects = filter_projects(projects)
 
@@ -117,6 +121,8 @@ module API
         use :pagination
       end
       get '/starred' do
+        authenticate!
+
         projects = current_user.viewable_starred_projects
         projects = filter_projects(projects)
 
@@ -132,6 +138,7 @@ module API
       end
       get '/all' do
         authenticated_as_admin!
+
         projects = Project.all
         projects = filter_projects(projects)
 
@@ -213,7 +220,8 @@ module API
         success Entities::ProjectWithAccess
       end
       get ":id" do
-        present user_project, with: Entities::ProjectWithAccess, user: current_user,
+        entity = current_user ? Entities::ProjectWithAccess : Entities::BasicProjectDetails
+        present user_project, with: entity, user: current_user,
                               user_can_admin_project: can?(current_user, :admin_project, user_project)
       end
 
@@ -433,7 +441,7 @@ module API
         use :pagination
       end
       get ':id/users' do
-        users = User.where(id: user_project.team.users.map(&:id))
+        users = user_project.team.users
         users = users.search(params[:search]) if params[:search].present?
 
         present paginate(users), with: Entities::UserBasic

spec/requests/api/api_helpers_spec.rb

@@ -47,7 +47,7 @@ describe API::Helpers, api: true do
   end
 
   def error!(message, status)
-    raise Exception
+    raise Exception.new("#{status} - #{message}")
   end
 
   describe ".current_user" do
@@ -290,4 +290,56 @@ describe API::Helpers, api: true do
       handle_api_exception(exception)
     end
   end
+
+  describe '.authenticate_non_get!' do
+    %w[HEAD GET].each do |method_name|
+      context "method is #{method_name}" do
+        before do
+          expect_any_instance_of(self.class).to receive(:route).and_return(double(route_method: method_name))
+        end
+
+        it 'does not raise an error' do
+          expect_any_instance_of(self.class).not_to receive(:authenticate!)
+
+          expect { authenticate_non_get! }.not_to raise_error
+        end
+      end
+    end
+
+    %w[POST PUT PATCH DELETE].each do |method_name|
+      context "method is #{method_name}" do
+        before do
+          expect_any_instance_of(self.class).to receive(:route).and_return(double(route_method: method_name))
+        end
+
+        it 'calls authenticate!' do
+          expect_any_instance_of(self.class).to receive(:authenticate!)
+
+          authenticate_non_get!
+        end
+      end
+    end
+  end
+
+  describe '.authenticate!' do
+    context 'current_user is nil' do
+      before do
+        expect_any_instance_of(self.class).to receive(:current_user).and_return(nil)
+      end
+
+      it 'returns a 401 response' do
+        expect { authenticate! }.to raise_error '401 - {"message"=>"401 Unauthorized"}'
+      end
+    end
+
+    context 'current_user is present' do
+      before do
+        expect_any_instance_of(self.class).to receive(:current_user).and_return(true)
+      end
+
+      it 'does not raise an error' do
+        expect { authenticate! }.not_to raise_error
+      end
+    end
+  end
 end