Namespace serializers for consuming controller (#538)

This change moves all serializers into the same namespace (`Api::V1`) as the controllers which consume those serializers. In doing so it fixes a bug which currently breaks almost any operation in staging, most notably user signup, by falling back to `Object#as_json` to serialize all API responses, not complying at all with our API spec.

`active_model_serializers` [looks for the serializers in this namespace by default](https://github.com/rails-api/active_model_serializers/blob/v0.9.8/lib/action_controller/serialization.rb#L62-L80), but this worked on Ruby 2.6.5:

```
[1] pry(#<Api::V1::RegistrationsController>)> r = Registration.create!(params)=> #<Registration:0x00007f96688f4f20
 @birth_date=nil,
 @captcha_response=
  "dummy-captcha-response",
 @errors=
  #<ActiveModel::Errors:0x00007f96688f4188
   @base=
    #<Registration:0x00007f96688f4f20 ...>,
   @errors=[]>,
 @screen_name="user",
 @user=
  #<User id: 1, email: "[email protected]", authentication_token: "03441d861500b01606fa928521b971eb", created_at: "2021-10-14 21:14:00.673552000 +0000", updated_at: "2021-10-14 21:14:00.673552000 +0000">,
 @user_params=
  {"email"=>"[email protected]",
   "password"=>"secret123",
   "password_confirmation"=>"secret123"}>
[2] pry(#<Api::V1::RegistrationsController>)> default_serializer(r)=> RegistrationSerializer
```

Since Ruby 2.6.6, [a change to constant lookup](ruby/ruby@15eba4e) was introduced which means that the appropriate class can't be found:

```
[2] pry(#<Api::V1::RegistrationsController>)> default_serializer(r)
=> nil
[3] pry(#<Api::V1::RegistrationsController>)> ActiveModel::Serializer.serializer_for(r, namespace: namespace_for_serializer)
=> nil
```

The reason is that while in both Ruby versions, the constant name that we try to look up is namespaced ([This namespacing behaviour is documented](https://github.com/rails-api/active_model_serializers/blob/v0.10.6/docs/general/rendering.md#namespace) in later releases, but the behaviour is similar in v0.9.x.):

```
[4] pry(#<Api::V1::RegistrationsController>)> ActiveModel::Serializer.send(:build_serializer_class, r, namespace: namespace_for_serializer)
=> "Api::V1::RegistrationSerializer"
```

this name [is passed to Object#const_get](https://github.com/rails-api/active_model_serializers/blob/ff1a36ffbc82c6070905707b29978a7b897dea81/lib/active_model/serializable/utils.rb#L6) which behaves more strictly since Ruby 2.6.6:

Ruby 2.6.5:

```
[5] pry(#<Api::V1::RegistrationsController>)> Object.const_get "Api::V1::RegistrationSerializer"
=> RegistrationSerializer
```

Ruby 2.6.6:

```
[5] pry(#<Api::V1::RegistrationsController>)> Object.const_get "Api::V1::RegistrationSerializer"
=> nil
```

It is considered appropriate to namespace the serializers together with the consuming controllers because together they constitute a cohesive definition of an API version; should an API V2 be introduced, it should likely have distinct serializers.

Author: benlangfeld

backend/app/controllers/api/v1/aws_ses_controller.rb

@@ -1,24 +1,28 @@
-class Api::V1::AwsSesController < ApplicationController
-  skip_authorize_resource only: [:mail_it, :notification]
-  skip_before_action :authenticate_user!, only: [:mail_it, :notification]
+module Api
+  module V1
+    class AwsSesController < ApplicationController
+      skip_authorize_resource only: [:mail_it, :notification]
+      skip_before_action :authenticate_user!, only: [:mail_it, :notification]
 
-  def notification
-    message_type = request.headers["x-amz-sns-message-type"]
-    # sns_topic = request.headers['x-amz-sns-topic-arn']
-    raw_post = request.raw_post
+      def notification
+        message_type = request.headers["x-amz-sns-message-type"]
+        # sns_topic = request.headers['x-amz-sns-topic-arn']
+        raw_post = request.raw_post
 
-    if message_type.include? "Confirmation"
-      send_subscription_confirmation(raw_post)
-    elsif message_type.include? "Notification"
-      EmailRejectDispatcher.perform_async(raw_post)
-    end
+        if message_type.include? "Confirmation"
+          send_subscription_confirmation(raw_post)
+        elsif message_type.include? "Notification"
+          EmailRejectDispatcher.perform_async(raw_post)
+        end
 
-    render nothing: true, status: 200
-  end
+        render nothing: true, status: 200
+      end
 
-  def send_subscription_confirmation(raw_post)
-    json = JSON.parse(raw_post)
+      def send_subscription_confirmation(raw_post)
+        json = JSON.parse(raw_post)
 
-    open(json["SubscribeURL"])
+        open(json["SubscribeURL"])
+      end
+    end
   end
 end

backend/app/controllers/api/v1/chart_lists_controller.rb

@@ -1,5 +1,9 @@
-class Api::V1::ChartListsController < ApplicationController
-  def show
-    render json: ChartListService.new(current_user: current_user).as_json
+module Api
+  module V1
+    class ChartListsController < ApplicationController
+      def show
+        render json: ChartListService.new(current_user: current_user).as_json
+      end
+    end
   end
 end

backend/app/controllers/api/v1/charts_controller.rb

@@ -1,28 +1,32 @@
-class Api::V1::ChartsController < ApplicationController
-  def show
-    chart = Chart.new(chart_params)
+module Api
+  module V1
+    class ChartsController < ApplicationController
+      def show
+        chart = Chart.new(chart_params)
 
-    # FIXME
-    # rubocop:disable Style/SignalException
-    fail(ActiveRecord::RecordInvalid, chart) if chart.invalid?
-    # rubocop:enable Style/SignalException
+        # FIXME
+        # rubocop:disable Style/SignalException
+        fail(ActiveRecord::RecordInvalid, chart) if chart.invalid?
+        # rubocop:enable Style/SignalException
 
-    render json: chart
-  end
+        render json: chart
+      end
 
-  def chart_params
-    includes_params = {
-      tags: [],
-      foods: [],
-      symptoms: [],
-      conditions: [],
-      treatments: [],
-      weathersMeasures: [],
-      harveyBradshawIndices: []
-    }
+      def chart_params
+        includes_params = {
+          tags: [],
+          foods: [],
+          symptoms: [],
+          conditions: [],
+          treatments: [],
+          weathersMeasures: [],
+          harveyBradshawIndices: []
+        }
 
-    params.permit(:id, :start_at, :end_at, includes: includes_params).tap do |whitelist|
-      whitelist[:user] = current_user
+        params.permit(:id, :start_at, :end_at, includes: includes_params).tap do |whitelist|
+          whitelist[:user] = current_user
+        end
+      end
     end
   end
 end

backend/app/controllers/api/v1/charts_pattern_controller.rb

@@ -1,27 +1,31 @@
-class Api::V1::ChartsPatternController < ApplicationController
-  skip_before_action :authenticate_user!, only: [:index]
+module Api
+  module V1
+    class ChartsPatternController < ApplicationController
+      skip_before_action :authenticate_user!, only: [:index]
 
-  def index
-    offset = charts_pattern_params[:offset].to_i
-    start_at = (charts_pattern_params[:start_at].to_date - offset.days).to_s
+      def index
+        offset = charts_pattern_params[:offset].to_i
+        start_at = (charts_pattern_params[:start_at].to_date - offset.days).to_s
 
-    end_date = charts_pattern_params[:end_at].to_date
-    end_at = (Time.current.to_date == end_date ? end_date : (end_date + offset.days)).to_s
+        end_date = charts_pattern_params[:end_at].to_date
+        end_at = (Time.current.to_date == end_date ? end_date : (end_date + offset.days)).to_s
 
-    @patterns = Pattern.where(id: {'$in': charts_pattern_params[:pattern_ids] || []})
+        @patterns = Pattern.where(id: {'$in': charts_pattern_params[:pattern_ids] || []})
 
-    @extended_patterns = @patterns.map do |pattern|
-      pattern.extend(PatternExtender).form_chart_data(start_at: start_at,
-        end_at: end_at,
-        pattern: pattern)
-    end
+        @extended_patterns = @patterns.map do |pattern|
+          pattern.extend(PatternExtender).form_chart_data(start_at: start_at,
+            end_at: end_at,
+            pattern: pattern)
+        end
 
-    render json: @extended_patterns, meta: {color_ids: Flaredown::Colorable::IDS}
-  end
+        render json: @extended_patterns, meta: {color_ids: Flaredown::Colorable::IDS}
+      end
 
-  private
+      private
 
-  def charts_pattern_params
-    params.permit(:start_at, :end_at, :offset, pattern_ids: [])
+      def charts_pattern_params
+        params.permit(:start_at, :end_at, :offset, pattern_ids: [])
+      end
+    end
   end
 end

backend/app/controllers/api/v1/checkins_controller.rb

@@ -1,31 +1,35 @@
-class Api::V1::CheckinsController < ApplicationController
-  def index
-    date = params[:date]
+module Api
+  module V1
+    class CheckinsController < ApplicationController
+      def index
+        date = params[:date]
 
-    if date.blank? && params.require(:page)
-      render json: current_user.checkins.where(:note.nin => [nil, ""]).order_by(date: :desc).page(params[:page]).per(10)
-    else
-      render json: current_user.checkins.where(date: Date.parse(date))
-    end
-  end
+        if date.blank? && params.require(:page)
+          render json: current_user.checkins.where(:note.nin => [nil, ""]).order_by(date: :desc).page(params[:page]).per(10)
+        else
+          render json: current_user.checkins.where(date: Date.parse(date))
+        end
+      end
 
-  def show
-    render json: Checkin.find(id)
-  end
+      def show
+        render json: Checkin.find(id)
+      end
 
-  def create
-    date = params.require(:checkin).require(:date)
-    checkin = Checkin::Creator.new(current_user.id, Date.parse(date)).create!
-    render json: checkin
-  end
+      def create
+        date = params.require(:checkin).require(:date)
+        checkin = Checkin::Creator.new(current_user.id, Date.parse(date)).create!
+        render json: checkin
+      end
 
-  def update
-    render json: Checkin::Updater.new(current_user, params).update!
-  end
+      def update
+        render json: Checkin::Updater.new(current_user, params).update!
+      end
 
-  private
+      private
 
-  def id
-    params.require(:id)
+      def id
+        params.require(:id)
+      end
+    end
   end
 end

backend/app/controllers/api/v1/comments_controller.rb

@@ -1,41 +1,45 @@
-class Api::V1::CommentsController < ApplicationController
-  load_and_authorize_resource
-  skip_before_action :authenticate_user!, only: [:index]
+module Api
+  module V1
+    class CommentsController < ApplicationController
+      load_and_authorize_resource
+      skip_before_action :authenticate_user!, only: [:index]
+
+      def index
+        render json: @comments.where(:id.in => params[:ids]).order_by(created_at: :asc)
+      end
 
-  def index
-    render json: @comments.where(:id.in => params[:ids]).order_by(created_at: :asc)
-  end
+      def show
+        render json: @comment
+      end
 
-  def show
-    render json: @comment
-  end
+      def create
+        @comment.encrypted_user_id = current_user.encrypted_id
+
+        if @comment.save
+          UpdatePostCountersJob.perform_async(parent_id: create_params[:post_id], parent_type: "Post")
 
-  def create
-    @comment.encrypted_user_id = current_user.encrypted_id
+          unless @comment.encrypted_user_id == @comment.post.encrypted_user_id
+            Notification.create(
+              kind: :comment,
+              notificateable: @comment,
+              encrypted_user_id: @comment.encrypted_user_id,
+              encrypted_notify_user_id: @comment.post.encrypted_user_id
+            )
+          end
 
-    if @comment.save
-      UpdatePostCountersJob.perform_async(parent_id: create_params[:post_id], parent_type: "Post")
+          DiscussionMention.perform_async(current_user.encrypted_id, @comment.id.to_s)
 
-      unless @comment.encrypted_user_id == @comment.post.encrypted_user_id
-        Notification.create(
-          kind: :comment,
-          notificateable: @comment,
-          encrypted_user_id: @comment.encrypted_user_id,
-          encrypted_notify_user_id: @comment.post.encrypted_user_id
-        )
+          render json: @comment, status: :created
+        else
+          render json: {errors: @comment.errors}, status: :unprocessable_entity
+        end
       end
 
-      DiscussionMention.perform_async(current_user.encrypted_id, @comment.id.to_s)
+      private
 
-      render json: @comment, status: :created
-    else
-      render json: {errors: @comment.errors}, status: :unprocessable_entity
+      def create_params
+        params.require(:comment).permit(:body, :post_id)
+      end
     end
   end
-
-  private
-
-  def create_params
-    params.require(:comment).permit(:body, :post_id)
-  end
 end

backend/app/controllers/api/v1/conditions_controller.rb

@@ -1,29 +1,33 @@
-class Api::V1::ConditionsController < ApplicationController
-  load_and_authorize_resource
-  skip_before_action :authenticate_user!, only: [:show]
+module Api
+  module V1
+    class ConditionsController < ApplicationController
+      load_and_authorize_resource
+      skip_before_action :authenticate_user!, only: [:show]
 
-  def index
-    @conditions = @conditions.includes(:translations)
-    @conditions = ids.present? ? @conditions.where(id: ids) : @conditions.order(:name).limit(50)
+      def index
+        @conditions = @conditions.includes(:translations)
+        @conditions = ids.present? ? @conditions.where(id: ids) : @conditions.order(:name).limit(50)
 
-    render json: @conditions
-  end
+        render json: @conditions
+      end
 
-  def show
-    render json: @condition
-  end
+      def show
+        render json: @condition
+      end
 
-  def create
-    render json: TrackableCreator.new(@condition, current_user).create!
-  end
+      def create
+        render json: TrackableCreator.new(@condition, current_user).create!
+      end
 
-  private
+      private
 
-  def create_params
-    params.require(:condition).permit(:name)
-  end
+      def create_params
+        params.require(:condition).permit(:name)
+      end
 
-  def ids
-    @ids ||= params[:ids] if params[:ids].is_a?(Array)
+      def ids
+        @ids ||= params[:ids] if params[:ids].is_a?(Array)
+      end
+    end
   end
 end