diff options
Diffstat (limited to 'config/initializers/ar5_batching.rb')
-rw-r--r-- | config/initializers/ar5_batching.rb | 41 |
1 files changed, 41 insertions, 0 deletions
diff --git a/config/initializers/ar5_batching.rb b/config/initializers/ar5_batching.rb new file mode 100644 index 00000000000..35e8b3808e2 --- /dev/null +++ b/config/initializers/ar5_batching.rb @@ -0,0 +1,41 @@ +# Port ActiveRecord::Relation#in_batches from ActiveRecord 5. +# https://github.com/rails/rails/blob/ac027338e4a165273607dccee49a3d38bc836794/activerecord/lib/active_record/relation/batches.rb#L184 +# TODO: this can be removed once we're using AR5. +raise "Vendored ActiveRecord 5 code! Delete #{__FILE__}!" if ActiveRecord::VERSION::MAJOR >= 5 + +module ActiveRecord + module Batches + # Differences from upstream: enumerator support was removed, and custom + # order/limit clauses are ignored without a warning. + def in_batches(of: 1000, start: nil, finish: nil, load: false) + raise "Must provide a block" unless block_given? + + relation = self.reorder(batch_order).limit(of) + relation = relation.where(arel_table[primary_key].gteq(start)) if start + relation = relation.where(arel_table[primary_key].lteq(finish)) if finish + batch_relation = relation + + loop do + if load + records = batch_relation.records + ids = records.map(&:id) + yielded_relation = self.where(primary_key => ids) + yielded_relation.load_records(records) + else + ids = batch_relation.pluck(primary_key) + yielded_relation = self.where(primary_key => ids) + end + + break if ids.empty? + + primary_key_offset = ids.last + raise ArgumentError.new("Primary key not included in the custom select clause") unless primary_key_offset + + yield yielded_relation + + break if ids.length < of + batch_relation = relation.where(arel_table[primary_key].gt(primary_key_offset)) + end + end + end +end |