107 lines
3.4 KiB
Ruby
107 lines
3.4 KiB
Ruby
# frozen_string_literal: true
|
|
|
|
module Gitlab
|
|
module Database
|
|
module Partitioning
|
|
class MonthlyStrategy
|
|
attr_reader :model, :partitioning_key, :retain_for, :retain_non_empty_partitions
|
|
|
|
# We create this many partitions in the future
|
|
HEADROOM = 6.months
|
|
|
|
delegate :table_name, to: :model
|
|
|
|
def initialize(model, partitioning_key, retain_for: nil, retain_non_empty_partitions: false)
|
|
@model = model
|
|
@partitioning_key = partitioning_key
|
|
@retain_for = retain_for
|
|
@retain_non_empty_partitions = retain_non_empty_partitions
|
|
end
|
|
|
|
def current_partitions
|
|
Gitlab::Database::PostgresPartition.for_parent_table(table_name).map do |partition|
|
|
TimePartition.from_sql(table_name, partition.name, partition.condition)
|
|
end
|
|
end
|
|
|
|
# Check the currently existing partitions and determine which ones are missing
|
|
def missing_partitions
|
|
desired_partitions - current_partitions
|
|
end
|
|
|
|
def extra_partitions
|
|
partitions = current_partitions - desired_partitions
|
|
partitions.reject!(&:holds_data?) if retain_non_empty_partitions
|
|
|
|
partitions
|
|
end
|
|
|
|
def after_adding_partitions
|
|
# No-op, required by the partition manager
|
|
end
|
|
|
|
private
|
|
|
|
def desired_partitions
|
|
[].tap do |parts|
|
|
min_date, max_date = relevant_range
|
|
|
|
if pruning_old_partitions? && min_date <= oldest_active_date
|
|
min_date = oldest_active_date.beginning_of_month
|
|
else
|
|
parts << partition_for(upper_bound: min_date)
|
|
end
|
|
|
|
while min_date < max_date
|
|
next_date = min_date.next_month
|
|
|
|
parts << partition_for(lower_bound: min_date, upper_bound: next_date)
|
|
|
|
min_date = next_date
|
|
end
|
|
end
|
|
end
|
|
|
|
# This determines the relevant time range for which we expect to have data
|
|
# (and therefore need to create partitions for).
|
|
#
|
|
# Note: We typically expect the first partition to be half-unbounded, i.e.
|
|
# to start from MINVALUE to a specific date `x`. The range returned
|
|
# does not include the range of the first, half-unbounded partition.
|
|
def relevant_range
|
|
if (first_partition = current_partitions.min)
|
|
# Case 1: First partition starts with MINVALUE, i.e. from is nil -> start with first real partition
|
|
# Case 2: Rather unexpectedly, first partition does not start with MINVALUE, i.e. from is not nil
|
|
# In this case, use first partition beginning as a start
|
|
min_date = first_partition.from || first_partition.to
|
|
end
|
|
|
|
if pruning_old_partitions?
|
|
min_date ||= oldest_active_date
|
|
end
|
|
|
|
# In case we don't have a partition yet
|
|
min_date ||= Date.today
|
|
min_date = min_date.beginning_of_month
|
|
|
|
max_date = Date.today.end_of_month + HEADROOM
|
|
|
|
[min_date, max_date]
|
|
end
|
|
|
|
def partition_for(lower_bound: nil, upper_bound:)
|
|
TimePartition.new(table_name, lower_bound, upper_bound)
|
|
end
|
|
|
|
def pruning_old_partitions?
|
|
retain_for.present?
|
|
end
|
|
|
|
def oldest_active_date
|
|
(Date.today - retain_for).beginning_of_month
|
|
end
|
|
end
|
|
end
|
|
end
|
|
end
|