use Float to define if received timestamp is float

app/controllers/api/v1/events_controller.rb

@@ -3,7 +3,6 @@
 module Api
   module V1
     class EventsController < Api::BaseController
-      before_action :validate_timestamp_format, only: [:create, :estimate_fees]
 
       def create
         result = ::Events::CreateService.call(
@@ -109,12 +108,6 @@ def estimate_fees
 
       private
 
-      def validate_timestamp_format
-        return if params[:event][:timestamp].to_f.to_s == params[:event][:timestamp].to_s
-
-        render json: { error: 'Invalid timestamp format' }, status: :unprocessable_entity
-      end
-
       def create_params
         params
           .require(:event)

app/services/events/create_service.rb

@@ -18,7 +18,7 @@ def call
       event.external_subscription_id = params[:external_subscription_id]
       event.properties = params[:properties] || {}
       event.metadata = metadata || {}
-      event.timestamp = Time.zone.at(params[:timestamp] ? params[:timestamp].to_f : timestamp)
+      event.timestamp = Time.zone.at(params[:timestamp] ? Float(params[:timestamp]) : timestamp)
       event.precise_total_amount_cents = params[:precise_total_amount_cents]
 
       CalculateExpressionService.call(organization:, event:).raise_if_error!
@@ -35,6 +35,8 @@ def call
       result.record_validation_failure!(record: e.record)
     rescue ActiveRecord::RecordNotUnique
       result.single_validation_failure!(field: :transaction_id, error_code: 'value_already_exist')
+    rescue ArgumentError
+      result.single_validation_failure!(field: :timestamp, error_code: 'invalid_format')
     end
 
     private

app/services/events/validate_creation_service.rb

@@ -37,13 +37,21 @@ def validate_create
         return missing_subscription_error
       end
 
+      return invalid_timestamp_error unless valid_timestamp?
       return transaction_id_error unless valid_transaction_id?
       return invalid_code_error unless valid_code?
       return invalid_properties_error unless valid_properties?
 
       nil
     end
 
+    def valid_timestamp?
+      return true if params[:timestamp].blank?
+
+      # timestamp is a number of seconds
+      valid_number?(params[:timestamp])
+    end
+
     def valid_transaction_id?
       return false if params[:transaction_id].blank?
 
@@ -92,6 +100,10 @@ def invalid_customer_error
       result.not_found_failure!(resource: 'customer')
     end
 
+    def invalid_timestamp_error
+      result.validation_failure!(errors: {timestamp: ['invalid_format']})
+    end
+
     def billable_metric
       @billable_metric ||= organization.billable_metrics.find_by(code: params[:code])
     end

spec/requests/api/v1/events_controller_spec.rb

@@ -77,6 +77,7 @@
         expect { subject }.not_to change(Event, :count)
 
         expect(response).to have_http_status(:unprocessable_entity)
+        expect(json[:error_details]).to eq({timestamp: ["invalid_format"]})
       end
     end
   end