Shallow Route receipts v4 (hackclub#10828)

## Summary of the problem
Can't add receipt bin receipts due to requiring to pass in transaction
ID in routes.


## Describe your changes
Added shallow routing


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gifs. -->

Author: thedev132

app/controllers/api/v4/receipts_controller.rb

@@ -4,20 +4,23 @@ module Api
   module V4
     class ReceiptsController < ApplicationController
       def index
-        @hcb_code = authorize HcbCode.find_by_public_id(params[:transaction_id]), :show?
-        @receipts = @hcb_code.receipts.includes(:user)
-      end
-
-      def receipt_bin
-        skip_authorization
-        @receipts = Receipt.in_receipt_bin.includes(:user).where(user: current_user)
-        render "index"
+        if params[:transaction_id].present?
+          @hcb_code = HcbCode.find_by_public_id(params[:transaction_id])
+          authorize @hcb_code, :show?
+          @receipts = @hcb_code.receipts.includes(:user)
+        else
+          skip_authorization
+          @receipts = Receipt.in_receipt_bin.includes(:user).where(user: current_user)
+        end
       end
 
       def create
-        @hcb_code = HcbCode.find_by_public_id(params[:transaction_id])
-        authorize @hcb_code, :upload?, policy_class: ReceiptablePolicy
-
+        if params[:transaction_id].present?
+          @hcb_code = HcbCode.find_by_public_id(params[:transaction_id])
+          authorize @hcb_code, :upload?, policy_class: ReceiptablePolicy
+        else
+          skip_authorization
+        end
         @receipt = Receipt.create!(file: params[:file], receiptable: @hcb_code, user: current_user, upload_method: :api)
 
         render "show"

config/routes.rb

@@ -575,15 +575,14 @@
           end
 
           get "transactions/missing_receipt", to: "transactions#missing_receipt"
-          get "receipt_bin", to: "receipts#receipt_bin"
           get :available_icons
         end
 
         resources :events, path: "organizations", only: [:show] do
           resources :stripe_cards, path: "cards", only: [:index]
           resources :card_grants, only: [:index, :create]
           resources :transactions, only: [:show, :update] do
-            resources :receipts, only: [:create, :index, :destroy]
+            resources :receipts, only: [:index]
             resources :comments, only: [:index, :create]
 
             member do
@@ -601,6 +600,7 @@
         end
 
         resources :transactions, only: [:show]
+        resources :receipts, only: [:create, :index, :destroy]
 
         resources :stripe_cards, path: "cards", only: [:show, :update, :create] do
           member do