MaxRowCountExceededError

app/controllers/imports_controller.rb

@@ -5,6 +5,8 @@ class ImportsController < ApplicationController
     @import.publish_later
 
     redirect_to import_path(@import), notice: "Your import has started in the background."
+  rescue Import::MaxRowCountExceededError
+    redirect_back_or_to import_path(@import), alert: "Your import exceeds the maximum row count of #{@import.max_row_count}."
   end
 
   def index

app/models/account_import.rb

@@ -1,7 +1,5 @@
 class AccountImport < Import
   def import!
-    raise "Account import is limited to 50 rows" if rows.count > 50
-
     transaction do
       rows.each do |row|
         mapping = mappings.account_types.find_by(key: row.entity_type)
@@ -56,4 +54,8 @@ class AccountImport < Import
 
     CSV.parse(template, headers: true)
   end
+
+  def max_row_count
+    50
+  end
 end

app/models/import.rb

@@ -1,4 +1,6 @@
 class Import < ApplicationRecord
+  MaxRowCountExceededError = Class.new(StandardError)
+
   TYPES = %w[TransactionImport TradeImport AccountImport MintImport].freeze
   SIGNAGE_CONVENTIONS = %w[inflows_positive inflows_negative]
   SEPARATORS = [ [ "Comma (,)", "," ], [ "Semicolon (;)", ";" ] ].freeze
@@ -52,6 +54,7 @@ class Import < ApplicationRecord
   end
 
   def publish_later
+    raise MaxRowCountExceededError if row_count_exceeded?
     raise "Import is not publishable" unless publishable?
 
     update! status: :importing
@@ -60,6 +63,8 @@ class Import < ApplicationRecord
   end
 
   def publish
+    raise MaxRowCountExceededError if row_count_exceeded?
+
     import!
 
     family.sync_later
@@ -220,7 +225,15 @@ class Import < ApplicationRecord
     )
   end
 
+  def max_row_count
+    10000
+  end
+
   private
+    def row_count_exceeded?
+      rows.count > max_row_count
+    end
+
     def import!
       # no-op, subclasses can implement for customization of algorithm
     end