implement project preference read settings endpoint

app/controllers/api/v1/project_preferences_controller.rb

@@ -8,11 +8,16 @@ class Api::V1::ProjectPreferencesController < Api::ApiController
   schema_type :json_schema
   before_action :find_upp_for_update_settings, only: [:update_settings]
 
+  def read_settings
+    skip_policy_scope
+    read_and_update_settings_response
+  end
+
   def update_settings
     skip_policy_scope
     @upp.settings.merge! params_for[:settings]
     @upp.save!
-    update_settings_response
+    read_and_update_settings_response
   end
 
   private
@@ -29,15 +34,30 @@ def user_allowed?
     @upp.project.owners_and_collaborators.include?(api_user.user) || api_user.is_admin?
   end
 
-  def update_settings_response
+  def read_and_update_settings_response
+    set_last_modified_header if action_name == "update_settings"
+
+    render_json_response
+  end
+
+  private
+
+  def set_last_modified_header
     response.headers['Last-Modified'] = @upp.updated_at.httpdate
+  end
+
+  def render_json_response
+    if action_name == "update_settings"
+      preferences = UserProjectPreference.where(id: @upp.id)
+    else
+      project = Project.find_by!(id: params[:project_id])
+      preferences = project.user_project_preference.where.not(email_communication: nil)
+      preferences = params[:user_id].present? ? preferences.where(user_id: params[:user_id]) : preferences
+    end
+
     render(
       status: :ok,
-      json_api: serializer.resource(
-        {},
-        UserProjectPreference.where(id: @upp.id),
-        context
-      )
+      json_api: serializer.resource({}, preferences, context)
     )
   end
 end

app/models/project.rb

@@ -15,6 +15,7 @@ class Project < ApplicationRecord
   has_many :tutorials
   has_many :field_guides, dependent: :destroy
   belongs_to :organization
+  has_many :user_project_preference
   # uses the activated_state enum on the workflow
   has_many :workflows,
     -> { where(serialize_with_project: true).active},

config/routes.rb

@@ -55,6 +55,7 @@
       json_api_resources :project_preferences do
         collection do
           post :update_settings
+          get :read_settings
         end
       end
 

spec/controllers/api/v1/project_preferences_controller_spec.rb

@@ -197,4 +197,45 @@
       end
     end
   end
+
+  describe '#read_settings' do
+    let!(:project) { create(:project, owner: authorized_user) }
+    let!(:upp) { create(:user_project_preference, project: project) }
+    let(:run_generic_read) { get :read_settings, params: { project_id: project.id, format: :json } }
+    let(:unauthorised_user) { create(:user) }
+    let(:run_unauthorised_user_read) { get :read_settings, params: { project_id: project.id, user_id: unauthorised_user.id, format: :json } }
+
+    describe 'genetic preferences' do
+      before(:each) do
+        default_request user_id: authorized_user.id, scopes: scopes
+        run_generic_read
+      end
+
+      it 'responds with a 200' do
+        expect(response.status).to eq(200)
+      end
+
+      it 'returns the correct response data' do
+        json_response = JSON.parse(response.body)
+        expect(json_response["project_preferences"]).to be_a(Array)
+        expect(json_response["project_preferences"].count).to eq(1)
+      end
+    end
+
+    describe 'user specific preferences' do
+      before(:each) do
+        default_request user_id: unauthorised_user.id, scopes: scopes
+        run_unauthorised_user_read
+      end
+
+      it 'responds with a 200' do
+        expect(response.status).to eq(200)
+      end
+
+      it 'returns the correct response data' do
+        json_response = JSON.parse(response.body)
+        expect(json_response["project_preferences"].count).to eq(0)
+      end
+    end
+  end
 end