6f5daf49d9
So funny story, true story. I tried to run the test locally, but didn't make it past setting up Gitaly. Here's what I tried: First attempt: `git clone gitlab-ce` `cd gitlab-ce && bundle install` `be rspec` This didn't work because I was missing the config/database.yml, I didn't see a `script/bootstrap` so I looked in the readme which redirected me to a webpage which redirected me to the gitlab-development-kit. Second attempt: `gem install gitlab-development-kit` cd gitlab-development-kit gdk init gdk isntall This broke somwhere along the way because it couldn't install Gitaly because my go version was too low. But it did clone the gitlab repo again and this time it did have a config/database.yml. So I tried to cd into it and `be rspec spec/lib/gitlab/database/migration_helpers_spec.rb` which complained about the database not being configured so I: - Changed the socket to localhost (in the config/database.yml) - `createdb <dev_db>` `createdb test_db` - `be rake db:test:prepare` Great success, it was doing things! But then failed when it came at the Gitaly step. Since I only want to change these three lines, at the point I gave up and entrusted the pipeline to do its thing. What I would have liked: - A 'It's a Rails system, I know this' readme/docs (It's in there somewhere just couldn't find it) - A way to run tests without having to use Gitaly - Not having too install all the things for a small fix (I get why'd you want this, but to me it's overkill)
1099 lines
40 KiB
Ruby
1099 lines
40 KiB
Ruby
# frozen_string_literal: true
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module Gitlab
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module Database
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module MigrationHelpers
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BACKGROUND_MIGRATION_BATCH_SIZE = 1000 # Number of rows to process per job
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BACKGROUND_MIGRATION_JOB_BUFFER_SIZE = 1000 # Number of jobs to bulk queue at a time
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# Adds `created_at` and `updated_at` columns with timezone information.
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#
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# This method is an improved version of Rails' built-in method `add_timestamps`.
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#
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# Available options are:
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# default - The default value for the column.
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# null - When set to `true` the column will allow NULL values.
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# The default is to not allow NULL values.
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def add_timestamps_with_timezone(table_name, options = {})
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options[:null] = false if options[:null].nil?
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[:created_at, :updated_at].each do |column_name|
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if options[:default] && transaction_open?
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raise '`add_timestamps_with_timezone` with default value cannot be run inside a transaction. ' \
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'You can disable transactions by calling `disable_ddl_transaction!` ' \
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'in the body of your migration class'
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end
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# If default value is presented, use `add_column_with_default` method instead.
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if options[:default]
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add_column_with_default(
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table_name,
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column_name,
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:datetime_with_timezone,
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default: options[:default],
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allow_null: options[:null]
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)
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else
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add_column(table_name, column_name, :datetime_with_timezone, options)
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end
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end
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end
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# Creates a new index, concurrently when supported
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#
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# On PostgreSQL this method creates an index concurrently, on MySQL this
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# creates a regular index.
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#
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# Example:
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#
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# add_concurrent_index :users, :some_column
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#
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# See Rails' `add_index` for more info on the available arguments.
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def add_concurrent_index(table_name, column_name, options = {})
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if transaction_open?
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raise 'add_concurrent_index can not be run inside a transaction, ' \
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'you can disable transactions by calling disable_ddl_transaction! ' \
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'in the body of your migration class'
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end
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if Database.postgresql?
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options = options.merge({ algorithm: :concurrently })
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end
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if index_exists?(table_name, column_name, options)
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Rails.logger.warn "Index not created because it already exists (this may be due to an aborted migration or similar): table_name: #{table_name}, column_name: #{column_name}"
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return
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end
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disable_statement_timeout do
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add_index(table_name, column_name, options)
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end
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end
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# Removes an existed index, concurrently when supported
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#
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# On PostgreSQL this method removes an index concurrently.
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#
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# Example:
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#
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# remove_concurrent_index :users, :some_column
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#
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# See Rails' `remove_index` for more info on the available arguments.
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def remove_concurrent_index(table_name, column_name, options = {})
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if transaction_open?
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raise 'remove_concurrent_index can not be run inside a transaction, ' \
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'you can disable transactions by calling disable_ddl_transaction! ' \
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'in the body of your migration class'
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end
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if supports_drop_index_concurrently?
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options = options.merge({ algorithm: :concurrently })
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end
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unless index_exists?(table_name, column_name, options)
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Rails.logger.warn "Index not removed because it does not exist (this may be due to an aborted migration or similar): table_name: #{table_name}, column_name: #{column_name}"
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return
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end
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disable_statement_timeout do
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remove_index(table_name, options.merge({ column: column_name }))
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end
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end
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# Removes an existing index, concurrently when supported
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#
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# On PostgreSQL this method removes an index concurrently.
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#
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# Example:
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#
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# remove_concurrent_index :users, "index_X_by_Y"
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#
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# See Rails' `remove_index` for more info on the available arguments.
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def remove_concurrent_index_by_name(table_name, index_name, options = {})
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if transaction_open?
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raise 'remove_concurrent_index_by_name can not be run inside a transaction, ' \
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'you can disable transactions by calling disable_ddl_transaction! ' \
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'in the body of your migration class'
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end
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if supports_drop_index_concurrently?
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options = options.merge({ algorithm: :concurrently })
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end
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unless index_exists_by_name?(table_name, index_name)
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Rails.logger.warn "Index not removed because it does not exist (this may be due to an aborted migration or similar): table_name: #{table_name}, index_name: #{index_name}"
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return
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end
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disable_statement_timeout do
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remove_index(table_name, options.merge({ name: index_name }))
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end
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end
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# Only available on Postgresql >= 9.2
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def supports_drop_index_concurrently?
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return false unless Database.postgresql?
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version = select_one("SELECT current_setting('server_version_num') AS v")['v'].to_i
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version >= 90200
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end
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# Adds a foreign key with only minimal locking on the tables involved.
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#
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# This method only requires minimal locking when using PostgreSQL. When
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# using MySQL this method will use Rails' default `add_foreign_key`.
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#
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# source - The source table containing the foreign key.
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# target - The target table the key points to.
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# column - The name of the column to create the foreign key on.
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# on_delete - The action to perform when associated data is removed,
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# defaults to "CASCADE".
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def add_concurrent_foreign_key(source, target, column:, on_delete: :cascade, name: nil)
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# Transactions would result in ALTER TABLE locks being held for the
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# duration of the transaction, defeating the purpose of this method.
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if transaction_open?
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raise 'add_concurrent_foreign_key can not be run inside a transaction'
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end
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# While MySQL does allow disabling of foreign keys it has no equivalent
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# of PostgreSQL's "VALIDATE CONSTRAINT". As a result we'll just fall
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# back to the normal foreign key procedure.
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if Database.mysql?
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if foreign_key_exists?(source, target, column: column)
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Rails.logger.warn "Foreign key not created because it exists already " \
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"(this may be due to an aborted migration or similar): " \
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"source: #{source}, target: #{target}, column: #{column}"
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return
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end
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key_options = { column: column, on_delete: on_delete }
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# The MySQL adapter tries to create a foreign key without a name when
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# `:name` is nil, instead of generating a name for us.
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key_options[:name] = name if name
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return add_foreign_key(source, target, key_options)
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else
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on_delete = 'SET NULL' if on_delete == :nullify
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end
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key_name = name || concurrent_foreign_key_name(source, column)
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unless foreign_key_exists?(source, target, column: column)
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Rails.logger.warn "Foreign key not created because it exists already " \
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"(this may be due to an aborted migration or similar): " \
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"source: #{source}, target: #{target}, column: #{column}"
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# Using NOT VALID allows us to create a key without immediately
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# validating it. This means we keep the ALTER TABLE lock only for a
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# short period of time. The key _is_ enforced for any newly created
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# data.
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execute <<-EOF.strip_heredoc
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ALTER TABLE #{source}
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ADD CONSTRAINT #{key_name}
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FOREIGN KEY (#{column})
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REFERENCES #{target} (id)
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#{on_delete ? "ON DELETE #{on_delete.upcase}" : ''}
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NOT VALID;
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EOF
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end
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# Validate the existing constraint. This can potentially take a very
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# long time to complete, but fortunately does not lock the source table
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# while running.
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#
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# Note this is a no-op in case the constraint is VALID already
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disable_statement_timeout do
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execute("ALTER TABLE #{source} VALIDATE CONSTRAINT #{key_name};")
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end
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end
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def foreign_key_exists?(source, target = nil, column: nil)
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foreign_keys(source).any? do |key|
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if column
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key.options[:column].to_s == column.to_s
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else
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key.to_table.to_s == target.to_s
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end
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end
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end
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# Returns the name for a concurrent foreign key.
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#
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# PostgreSQL constraint names have a limit of 63 bytes. The logic used
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# here is based on Rails' foreign_key_name() method, which unfortunately
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# is private so we can't rely on it directly.
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def concurrent_foreign_key_name(table, column)
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identifier = "#{table}_#{column}_fk"
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hashed_identifier = Digest::SHA256.hexdigest(identifier).first(10)
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"fk_#{hashed_identifier}"
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end
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# Long-running migrations may take more than the timeout allowed by
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# the database. Disable the session's statement timeout to ensure
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# migrations don't get killed prematurely. (PostgreSQL only)
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#
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# There are two possible ways to disable the statement timeout:
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#
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# - Per transaction (this is the preferred and default mode)
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# - Per connection (requires a cleanup after the execution)
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#
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# When using a per connection disable statement, code must be inside
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# a block so we can automatically execute `RESET ALL` after block finishes
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# otherwise the statement will still be disabled until connection is dropped
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# or `RESET ALL` is executed
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def disable_statement_timeout
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# bypass disabled_statement logic when not using postgres, but still execute block when one is given
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unless Database.postgresql?
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if block_given?
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yield
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end
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return
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end
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if block_given?
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begin
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execute('SET statement_timeout TO 0')
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yield
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ensure
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execute('RESET ALL')
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end
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else
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unless transaction_open?
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raise <<~ERROR
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Cannot call disable_statement_timeout() without a transaction open or outside of a transaction block.
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If you don't want to use a transaction wrap your code in a block call:
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disable_statement_timeout { # code that requires disabled statement here }
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This will make sure statement_timeout is disabled before and reset after the block execution is finished.
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ERROR
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end
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execute('SET LOCAL statement_timeout TO 0')
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end
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end
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def true_value
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Database.true_value
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end
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def false_value
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Database.false_value
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end
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# Updates the value of a column in batches.
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#
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# This method updates the table in batches of 5% of the total row count.
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# A `batch_size` option can also be passed to set this to a fixed number.
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# This method will continue updating rows until no rows remain.
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#
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# When given a block this method will yield two values to the block:
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#
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# 1. An instance of `Arel::Table` for the table that is being updated.
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# 2. The query to run as an Arel object.
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#
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# By supplying a block one can add extra conditions to the queries being
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# executed. Note that the same block is used for _all_ queries.
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#
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# Example:
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#
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# update_column_in_batches(:projects, :foo, 10) do |table, query|
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# query.where(table[:some_column].eq('hello'))
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# end
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#
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# This would result in this method updating only rows where
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# `projects.some_column` equals "hello".
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#
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# table - The name of the table.
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# column - The name of the column to update.
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# value - The value for the column.
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#
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# The `value` argument is typically a literal. To perform a computed
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# update, an Arel literal can be used instead:
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#
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# update_value = Arel.sql('bar * baz')
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#
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# update_column_in_batches(:projects, :foo, update_value) do |table, query|
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# query.where(table[:some_column].eq('hello'))
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# end
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#
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# Rubocop's Metrics/AbcSize metric is disabled for this method as Rubocop
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# determines this method to be too complex while there's no way to make it
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# less "complex" without introducing extra methods (which actually will
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# make things _more_ complex).
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#
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# rubocop: disable Metrics/AbcSize
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def update_column_in_batches(table, column, value, batch_size: nil)
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if transaction_open?
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raise 'update_column_in_batches can not be run inside a transaction, ' \
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'you can disable transactions by calling disable_ddl_transaction! ' \
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'in the body of your migration class'
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end
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table = Arel::Table.new(table)
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count_arel = table.project(Arel.star.count.as('count'))
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count_arel = yield table, count_arel if block_given?
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total = exec_query(count_arel.to_sql).to_hash.first['count'].to_i
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return if total == 0
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if batch_size.nil?
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# Update in batches of 5% until we run out of any rows to update.
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batch_size = ((total / 100.0) * 5.0).ceil
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max_size = 1000
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# The upper limit is 1000 to ensure we don't lock too many rows. For
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# example, for "merge_requests" even 1% of the table is around 35 000
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# rows for GitLab.com.
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batch_size = max_size if batch_size > max_size
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end
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start_arel = table.project(table[:id]).order(table[:id].asc).take(1)
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start_arel = yield table, start_arel if block_given?
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start_id = exec_query(start_arel.to_sql).to_hash.first['id'].to_i
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loop do
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stop_arel = table.project(table[:id])
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.where(table[:id].gteq(start_id))
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.order(table[:id].asc)
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.take(1)
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.skip(batch_size)
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stop_arel = yield table, stop_arel if block_given?
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stop_row = exec_query(stop_arel.to_sql).to_hash.first
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update_arel = Arel::UpdateManager.new
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.table(table)
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.set([[table[column], value]])
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.where(table[:id].gteq(start_id))
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if stop_row
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stop_id = stop_row['id'].to_i
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start_id = stop_id
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update_arel = update_arel.where(table[:id].lt(stop_id))
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end
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update_arel = yield table, update_arel if block_given?
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execute(update_arel.to_sql)
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# There are no more rows left to update.
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break unless stop_row
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end
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end
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# Adds a column with a default value without locking an entire table.
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#
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# This method runs the following steps:
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#
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# 1. Add the column with a default value of NULL.
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# 2. Change the default value of the column to the specified value.
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# 3. Update all existing rows in batches.
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# 4. Set a `NOT NULL` constraint on the column if desired (the default).
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#
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# These steps ensure a column can be added to a large and commonly used
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# table without locking the entire table for the duration of the table
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# modification.
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#
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# table - The name of the table to update.
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# column - The name of the column to add.
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# type - The column type (e.g. `:integer`).
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# default - The default value for the column.
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# limit - Sets a column limit. For example, for :integer, the default is
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# 4-bytes. Set `limit: 8` to allow 8-byte integers.
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# allow_null - When set to `true` the column will allow NULL values, the
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# default is to not allow NULL values.
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#
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# This method can also take a block which is passed directly to the
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# `update_column_in_batches` method.
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def add_column_with_default(table, column, type, default:, limit: nil, allow_null: false, &block)
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if transaction_open?
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raise 'add_column_with_default can not be run inside a transaction, ' \
|
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'you can disable transactions by calling disable_ddl_transaction! ' \
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'in the body of your migration class'
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end
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disable_statement_timeout do
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transaction do
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if limit
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add_column(table, column, type, default: nil, limit: limit)
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else
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add_column(table, column, type, default: nil)
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end
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# Changing the default before the update ensures any newly inserted
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# rows already use the proper default value.
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change_column_default(table, column, default)
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end
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begin
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update_column_in_batches(table, column, default, &block)
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change_column_null(table, column, false) unless allow_null
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# We want to rescue _all_ exceptions here, even those that don't inherit
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# from StandardError.
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rescue Exception => error # rubocop: disable all
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remove_column(table, column)
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raise error
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end
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end
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end
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|
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# Renames a column without requiring downtime.
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#
|
|
# Concurrent renames work by using database triggers to ensure both the
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# old and new column are in sync. However, this method will _not_ remove
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# the triggers or the old column automatically; this needs to be done
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# manually in a post-deployment migration. This can be done using the
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# method `cleanup_concurrent_column_rename`.
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#
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# table - The name of the database table containing the column.
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# old - The old column name.
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# new - The new column name.
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# type - The type of the new column. If no type is given the old column's
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# type is used.
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def rename_column_concurrently(table, old, new, type: nil)
|
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if transaction_open?
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raise 'rename_column_concurrently can not be run inside a transaction'
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end
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check_trigger_permissions!(table)
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old_col = column_for(table, old)
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new_type = type || old_col.type
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add_column(table, new, new_type,
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limit: old_col.limit,
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precision: old_col.precision,
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scale: old_col.scale)
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# We set the default value _after_ adding the column so we don't end up
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# updating any existing data with the default value. This isn't
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# necessary since we copy over old values further down.
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change_column_default(table, new, old_col.default) if old_col.default
|
|
|
|
install_rename_triggers(table, old, new)
|
|
|
|
update_column_in_batches(table, new, Arel::Table.new(table)[old])
|
|
|
|
change_column_null(table, new, false) unless old_col.null
|
|
|
|
copy_indexes(table, old, new)
|
|
copy_foreign_keys(table, old, new)
|
|
end
|
|
|
|
# Installs triggers in a table that keep a new column in sync with an old
|
|
# one.
|
|
#
|
|
# table - The name of the table to install the trigger in.
|
|
# old_column - The name of the old column.
|
|
# new_column - The name of the new column.
|
|
def install_rename_triggers(table, old_column, new_column)
|
|
trigger_name = rename_trigger_name(table, old_column, new_column)
|
|
quoted_table = quote_table_name(table)
|
|
quoted_old = quote_column_name(old_column)
|
|
quoted_new = quote_column_name(new_column)
|
|
|
|
if Database.postgresql?
|
|
install_rename_triggers_for_postgresql(trigger_name, quoted_table,
|
|
quoted_old, quoted_new)
|
|
else
|
|
install_rename_triggers_for_mysql(trigger_name, quoted_table,
|
|
quoted_old, quoted_new)
|
|
end
|
|
end
|
|
|
|
# Changes the type of a column concurrently.
|
|
#
|
|
# table - The table containing the column.
|
|
# column - The name of the column to change.
|
|
# new_type - The new column type.
|
|
def change_column_type_concurrently(table, column, new_type)
|
|
temp_column = "#{column}_for_type_change"
|
|
|
|
rename_column_concurrently(table, column, temp_column, type: new_type)
|
|
end
|
|
|
|
# Performs cleanup of a concurrent type change.
|
|
#
|
|
# table - The table containing the column.
|
|
# column - The name of the column to change.
|
|
# new_type - The new column type.
|
|
def cleanup_concurrent_column_type_change(table, column)
|
|
temp_column = "#{column}_for_type_change"
|
|
|
|
transaction do
|
|
# This has to be performed in a transaction as otherwise we might have
|
|
# inconsistent data.
|
|
cleanup_concurrent_column_rename(table, column, temp_column)
|
|
rename_column(table, temp_column, column)
|
|
end
|
|
end
|
|
|
|
# Cleans up a concurrent column name.
|
|
#
|
|
# This method takes care of removing previously installed triggers as well
|
|
# as removing the old column.
|
|
#
|
|
# table - The name of the database table.
|
|
# old - The name of the old column.
|
|
# new - The name of the new column.
|
|
def cleanup_concurrent_column_rename(table, old, new)
|
|
trigger_name = rename_trigger_name(table, old, new)
|
|
|
|
check_trigger_permissions!(table)
|
|
|
|
if Database.postgresql?
|
|
remove_rename_triggers_for_postgresql(table, trigger_name)
|
|
else
|
|
remove_rename_triggers_for_mysql(trigger_name)
|
|
end
|
|
|
|
remove_column(table, old)
|
|
end
|
|
|
|
# Changes the column type of a table using a background migration.
|
|
#
|
|
# Because this method uses a background migration it's more suitable for
|
|
# large tables. For small tables it's better to use
|
|
# `change_column_type_concurrently` since it can complete its work in a
|
|
# much shorter amount of time and doesn't rely on Sidekiq.
|
|
#
|
|
# Example usage:
|
|
#
|
|
# class Issue < ActiveRecord::Base
|
|
# self.table_name = 'issues'
|
|
#
|
|
# include EachBatch
|
|
#
|
|
# def self.to_migrate
|
|
# where('closed_at IS NOT NULL')
|
|
# end
|
|
# end
|
|
#
|
|
# change_column_type_using_background_migration(
|
|
# Issue.to_migrate,
|
|
# :closed_at,
|
|
# :datetime_with_timezone
|
|
# )
|
|
#
|
|
# Reverting a migration like this is done exactly the same way, just with
|
|
# a different type to migrate to (e.g. `:datetime` in the above example).
|
|
#
|
|
# relation - An ActiveRecord relation to use for scheduling jobs and
|
|
# figuring out what table we're modifying. This relation _must_
|
|
# have the EachBatch module included.
|
|
#
|
|
# column - The name of the column for which the type will be changed.
|
|
#
|
|
# new_type - The new type of the column.
|
|
#
|
|
# batch_size - The number of rows to schedule in a single background
|
|
# migration.
|
|
#
|
|
# interval - The time interval between every background migration.
|
|
def change_column_type_using_background_migration(
|
|
relation,
|
|
column,
|
|
new_type,
|
|
batch_size: 10_000,
|
|
interval: 10.minutes
|
|
)
|
|
|
|
unless relation.model < EachBatch
|
|
raise TypeError, 'The relation must include the EachBatch module'
|
|
end
|
|
|
|
temp_column = "#{column}_for_type_change"
|
|
table = relation.table_name
|
|
max_index = 0
|
|
|
|
add_column(table, temp_column, new_type)
|
|
install_rename_triggers(table, column, temp_column)
|
|
|
|
# Schedule the jobs that will copy the data from the old column to the
|
|
# new one. Rows with NULL values in our source column are skipped since
|
|
# the target column is already NULL at this point.
|
|
relation.where.not(column => nil).each_batch(of: batch_size) do |batch, index|
|
|
start_id, end_id = batch.pluck('MIN(id), MAX(id)').first
|
|
max_index = index
|
|
|
|
BackgroundMigrationWorker.perform_in(
|
|
index * interval,
|
|
'CopyColumn',
|
|
[table, column, temp_column, start_id, end_id]
|
|
)
|
|
end
|
|
|
|
# Schedule the renaming of the column to happen (initially) 1 hour after
|
|
# the last batch finished.
|
|
BackgroundMigrationWorker.perform_in(
|
|
(max_index * interval) + 1.hour,
|
|
'CleanupConcurrentTypeChange',
|
|
[table, column, temp_column]
|
|
)
|
|
|
|
if perform_background_migration_inline?
|
|
# To ensure the schema is up to date immediately we perform the
|
|
# migration inline in dev / test environments.
|
|
Gitlab::BackgroundMigration.steal('CopyColumn')
|
|
Gitlab::BackgroundMigration.steal('CleanupConcurrentTypeChange')
|
|
end
|
|
end
|
|
|
|
# Renames a column using a background migration.
|
|
#
|
|
# Because this method uses a background migration it's more suitable for
|
|
# large tables. For small tables it's better to use
|
|
# `rename_column_concurrently` since it can complete its work in a much
|
|
# shorter amount of time and doesn't rely on Sidekiq.
|
|
#
|
|
# Example usage:
|
|
#
|
|
# rename_column_using_background_migration(
|
|
# :users,
|
|
# :feed_token,
|
|
# :rss_token
|
|
# )
|
|
#
|
|
# table - The name of the database table containing the column.
|
|
#
|
|
# old - The old column name.
|
|
#
|
|
# new - The new column name.
|
|
#
|
|
# type - The type of the new column. If no type is given the old column's
|
|
# type is used.
|
|
#
|
|
# batch_size - The number of rows to schedule in a single background
|
|
# migration.
|
|
#
|
|
# interval - The time interval between every background migration.
|
|
def rename_column_using_background_migration(
|
|
table,
|
|
old_column,
|
|
new_column,
|
|
type: nil,
|
|
batch_size: 10_000,
|
|
interval: 10.minutes
|
|
)
|
|
|
|
check_trigger_permissions!(table)
|
|
|
|
old_col = column_for(table, old_column)
|
|
new_type = type || old_col.type
|
|
max_index = 0
|
|
|
|
add_column(table, new_column, new_type,
|
|
limit: old_col.limit,
|
|
precision: old_col.precision,
|
|
scale: old_col.scale)
|
|
|
|
# We set the default value _after_ adding the column so we don't end up
|
|
# updating any existing data with the default value. This isn't
|
|
# necessary since we copy over old values further down.
|
|
change_column_default(table, new_column, old_col.default) if old_col.default
|
|
|
|
install_rename_triggers(table, old_column, new_column)
|
|
|
|
model = Class.new(ActiveRecord::Base) do
|
|
self.table_name = table
|
|
|
|
include ::EachBatch
|
|
end
|
|
|
|
# Schedule the jobs that will copy the data from the old column to the
|
|
# new one. Rows with NULL values in our source column are skipped since
|
|
# the target column is already NULL at this point.
|
|
model.where.not(old_column => nil).each_batch(of: batch_size) do |batch, index|
|
|
start_id, end_id = batch.pluck('MIN(id), MAX(id)').first
|
|
max_index = index
|
|
|
|
BackgroundMigrationWorker.perform_in(
|
|
index * interval,
|
|
'CopyColumn',
|
|
[table, old_column, new_column, start_id, end_id]
|
|
)
|
|
end
|
|
|
|
# Schedule the renaming of the column to happen (initially) 1 hour after
|
|
# the last batch finished.
|
|
BackgroundMigrationWorker.perform_in(
|
|
(max_index * interval) + 1.hour,
|
|
'CleanupConcurrentRename',
|
|
[table, old_column, new_column]
|
|
)
|
|
|
|
if perform_background_migration_inline?
|
|
# To ensure the schema is up to date immediately we perform the
|
|
# migration inline in dev / test environments.
|
|
Gitlab::BackgroundMigration.steal('CopyColumn')
|
|
Gitlab::BackgroundMigration.steal('CleanupConcurrentRename')
|
|
end
|
|
end
|
|
|
|
def perform_background_migration_inline?
|
|
Rails.env.test? || Rails.env.development?
|
|
end
|
|
|
|
# Performs a concurrent column rename when using PostgreSQL.
|
|
def install_rename_triggers_for_postgresql(trigger, table, old, new)
|
|
execute <<-EOF.strip_heredoc
|
|
CREATE OR REPLACE FUNCTION #{trigger}()
|
|
RETURNS trigger AS
|
|
$BODY$
|
|
BEGIN
|
|
NEW.#{new} := NEW.#{old};
|
|
RETURN NEW;
|
|
END;
|
|
$BODY$
|
|
LANGUAGE 'plpgsql'
|
|
VOLATILE
|
|
EOF
|
|
|
|
execute <<-EOF.strip_heredoc
|
|
CREATE TRIGGER #{trigger}
|
|
BEFORE INSERT OR UPDATE
|
|
ON #{table}
|
|
FOR EACH ROW
|
|
EXECUTE PROCEDURE #{trigger}()
|
|
EOF
|
|
end
|
|
|
|
# Installs the triggers necessary to perform a concurrent column rename on
|
|
# MySQL.
|
|
def install_rename_triggers_for_mysql(trigger, table, old, new)
|
|
execute <<-EOF.strip_heredoc
|
|
CREATE TRIGGER #{trigger}_insert
|
|
BEFORE INSERT
|
|
ON #{table}
|
|
FOR EACH ROW
|
|
SET NEW.#{new} = NEW.#{old}
|
|
EOF
|
|
|
|
execute <<-EOF.strip_heredoc
|
|
CREATE TRIGGER #{trigger}_update
|
|
BEFORE UPDATE
|
|
ON #{table}
|
|
FOR EACH ROW
|
|
SET NEW.#{new} = NEW.#{old}
|
|
EOF
|
|
end
|
|
|
|
# Removes the triggers used for renaming a PostgreSQL column concurrently.
|
|
def remove_rename_triggers_for_postgresql(table, trigger)
|
|
execute("DROP TRIGGER IF EXISTS #{trigger} ON #{table}")
|
|
execute("DROP FUNCTION IF EXISTS #{trigger}()")
|
|
end
|
|
|
|
# Removes the triggers used for renaming a MySQL column concurrently.
|
|
def remove_rename_triggers_for_mysql(trigger)
|
|
execute("DROP TRIGGER IF EXISTS #{trigger}_insert")
|
|
execute("DROP TRIGGER IF EXISTS #{trigger}_update")
|
|
end
|
|
|
|
# Returns the (base) name to use for triggers when renaming columns.
|
|
def rename_trigger_name(table, old, new)
|
|
'trigger_' + Digest::SHA256.hexdigest("#{table}_#{old}_#{new}").first(12)
|
|
end
|
|
|
|
# Returns an Array containing the indexes for the given column
|
|
def indexes_for(table, column)
|
|
column = column.to_s
|
|
|
|
indexes(table).select { |index| index.columns.include?(column) }
|
|
end
|
|
|
|
# Returns an Array containing the foreign keys for the given column.
|
|
def foreign_keys_for(table, column)
|
|
column = column.to_s
|
|
|
|
foreign_keys(table).select { |fk| fk.column == column }
|
|
end
|
|
|
|
# Copies all indexes for the old column to a new column.
|
|
#
|
|
# table - The table containing the columns and indexes.
|
|
# old - The old column.
|
|
# new - The new column.
|
|
def copy_indexes(table, old, new)
|
|
old = old.to_s
|
|
new = new.to_s
|
|
|
|
indexes_for(table, old).each do |index|
|
|
new_columns = index.columns.map do |column|
|
|
column == old ? new : column
|
|
end
|
|
|
|
# This is necessary as we can't properly rename indexes such as
|
|
# "ci_taggings_idx".
|
|
unless index.name.include?(old)
|
|
raise "The index #{index.name} can not be copied as it does not "\
|
|
"mention the old column. You have to rename this index manually first."
|
|
end
|
|
|
|
name = index.name.gsub(old, new)
|
|
|
|
options = {
|
|
unique: index.unique,
|
|
name: name,
|
|
length: index.lengths,
|
|
order: index.orders
|
|
}
|
|
|
|
# These options are not supported by MySQL, so we only add them if
|
|
# they were previously set.
|
|
options[:using] = index.using if index.using
|
|
options[:where] = index.where if index.where
|
|
|
|
unless index.opclasses.blank?
|
|
opclasses = index.opclasses.dup
|
|
|
|
# Copy the operator classes for the old column (if any) to the new
|
|
# column.
|
|
opclasses[new] = opclasses.delete(old) if opclasses[old]
|
|
|
|
options[:opclasses] = opclasses
|
|
end
|
|
|
|
add_concurrent_index(table, new_columns, options)
|
|
end
|
|
end
|
|
|
|
# Copies all foreign keys for the old column to the new column.
|
|
#
|
|
# table - The table containing the columns and indexes.
|
|
# old - The old column.
|
|
# new - The new column.
|
|
def copy_foreign_keys(table, old, new)
|
|
foreign_keys_for(table, old).each do |fk|
|
|
add_concurrent_foreign_key(fk.from_table,
|
|
fk.to_table,
|
|
column: new,
|
|
on_delete: fk.on_delete)
|
|
end
|
|
end
|
|
|
|
# Returns the column for the given table and column name.
|
|
def column_for(table, name)
|
|
name = name.to_s
|
|
|
|
columns(table).find { |column| column.name == name }
|
|
end
|
|
|
|
# This will replace the first occurrence of a string in a column with
|
|
# the replacement
|
|
# On postgresql we can use `regexp_replace` for that.
|
|
# On mysql we find the location of the pattern, and overwrite it
|
|
# with the replacement
|
|
def replace_sql(column, pattern, replacement)
|
|
quoted_pattern = Arel::Nodes::Quoted.new(pattern.to_s)
|
|
quoted_replacement = Arel::Nodes::Quoted.new(replacement.to_s)
|
|
|
|
if Database.mysql?
|
|
locate = Arel::Nodes::NamedFunction
|
|
.new('locate', [quoted_pattern, column])
|
|
insert_in_place = Arel::Nodes::NamedFunction
|
|
.new('insert', [column, locate, pattern.size, quoted_replacement])
|
|
|
|
Arel::Nodes::SqlLiteral.new(insert_in_place.to_sql)
|
|
else
|
|
replace = Arel::Nodes::NamedFunction
|
|
.new("regexp_replace", [column, quoted_pattern, quoted_replacement])
|
|
Arel::Nodes::SqlLiteral.new(replace.to_sql)
|
|
end
|
|
end
|
|
|
|
def remove_foreign_key_if_exists(*args)
|
|
if foreign_key_exists?(*args)
|
|
remove_foreign_key(*args)
|
|
end
|
|
end
|
|
|
|
def remove_foreign_key_without_error(*args)
|
|
remove_foreign_key(*args)
|
|
rescue ArgumentError
|
|
end
|
|
|
|
def sidekiq_queue_migrate(queue_from, to:)
|
|
while sidekiq_queue_length(queue_from) > 0
|
|
Sidekiq.redis do |conn|
|
|
conn.rpoplpush "queue:#{queue_from}", "queue:#{to}"
|
|
end
|
|
end
|
|
end
|
|
|
|
def sidekiq_queue_length(queue_name)
|
|
Sidekiq.redis do |conn|
|
|
conn.llen("queue:#{queue_name}")
|
|
end
|
|
end
|
|
|
|
def check_trigger_permissions!(table)
|
|
unless Grant.create_and_execute_trigger?(table)
|
|
dbname = Database.database_name
|
|
user = Database.username
|
|
|
|
raise <<-EOF
|
|
Your database user is not allowed to create, drop, or execute triggers on the
|
|
table #{table}.
|
|
|
|
If you are using PostgreSQL you can solve this by logging in to the GitLab
|
|
database (#{dbname}) using a super user and running:
|
|
|
|
ALTER #{user} WITH SUPERUSER
|
|
|
|
For MySQL you instead need to run:
|
|
|
|
GRANT ALL PRIVILEGES ON #{dbname}.* TO #{user}@'%'
|
|
|
|
Both queries will grant the user super user permissions, ensuring you don't run
|
|
into similar problems in the future (e.g. when new tables are created).
|
|
EOF
|
|
end
|
|
end
|
|
|
|
# Bulk queues background migration jobs for an entire table, batched by ID range.
|
|
# "Bulk" meaning many jobs will be pushed at a time for efficiency.
|
|
# If you need a delay interval per job, then use `queue_background_migration_jobs_by_range_at_intervals`.
|
|
#
|
|
# model_class - The table being iterated over
|
|
# job_class_name - The background migration job class as a string
|
|
# batch_size - The maximum number of rows per job
|
|
#
|
|
# Example:
|
|
#
|
|
# class Route < ActiveRecord::Base
|
|
# include EachBatch
|
|
# self.table_name = 'routes'
|
|
# end
|
|
#
|
|
# bulk_queue_background_migration_jobs_by_range(Route, 'ProcessRoutes')
|
|
#
|
|
# Where the model_class includes EachBatch, and the background migration exists:
|
|
#
|
|
# class Gitlab::BackgroundMigration::ProcessRoutes
|
|
# def perform(start_id, end_id)
|
|
# # do something
|
|
# end
|
|
# end
|
|
def bulk_queue_background_migration_jobs_by_range(model_class, job_class_name, batch_size: BACKGROUND_MIGRATION_BATCH_SIZE)
|
|
raise "#{model_class} does not have an ID to use for batch ranges" unless model_class.column_names.include?('id')
|
|
|
|
jobs = []
|
|
table_name = model_class.quoted_table_name
|
|
|
|
model_class.each_batch(of: batch_size) do |relation|
|
|
start_id, end_id = relation.pluck("MIN(#{table_name}.id), MAX(#{table_name}.id)").first
|
|
|
|
if jobs.length >= BACKGROUND_MIGRATION_JOB_BUFFER_SIZE
|
|
# Note: This code path generally only helps with many millions of rows
|
|
# We push multiple jobs at a time to reduce the time spent in
|
|
# Sidekiq/Redis operations. We're using this buffer based approach so we
|
|
# don't need to run additional queries for every range.
|
|
BackgroundMigrationWorker.bulk_perform_async(jobs)
|
|
jobs.clear
|
|
end
|
|
|
|
jobs << [job_class_name, [start_id, end_id]]
|
|
end
|
|
|
|
BackgroundMigrationWorker.bulk_perform_async(jobs) unless jobs.empty?
|
|
end
|
|
|
|
# Queues background migration jobs for an entire table, batched by ID range.
|
|
# Each job is scheduled with a `delay_interval` in between.
|
|
# If you use a small interval, then some jobs may run at the same time.
|
|
#
|
|
# model_class - The table or relation being iterated over
|
|
# job_class_name - The background migration job class as a string
|
|
# delay_interval - The duration between each job's scheduled time (must respond to `to_f`)
|
|
# batch_size - The maximum number of rows per job
|
|
#
|
|
# Example:
|
|
#
|
|
# class Route < ActiveRecord::Base
|
|
# include EachBatch
|
|
# self.table_name = 'routes'
|
|
# end
|
|
#
|
|
# queue_background_migration_jobs_by_range_at_intervals(Route, 'ProcessRoutes', 1.minute)
|
|
#
|
|
# Where the model_class includes EachBatch, and the background migration exists:
|
|
#
|
|
# class Gitlab::BackgroundMigration::ProcessRoutes
|
|
# def perform(start_id, end_id)
|
|
# # do something
|
|
# end
|
|
# end
|
|
def queue_background_migration_jobs_by_range_at_intervals(model_class, job_class_name, delay_interval, batch_size: BACKGROUND_MIGRATION_BATCH_SIZE)
|
|
raise "#{model_class} does not have an ID to use for batch ranges" unless model_class.column_names.include?('id')
|
|
|
|
# To not overload the worker too much we enforce a minimum interval both
|
|
# when scheduling and performing jobs.
|
|
if delay_interval < BackgroundMigrationWorker.minimum_interval
|
|
delay_interval = BackgroundMigrationWorker.minimum_interval
|
|
end
|
|
|
|
model_class.each_batch(of: batch_size) do |relation, index|
|
|
start_id, end_id = relation.pluck('MIN(id), MAX(id)').first
|
|
|
|
# `BackgroundMigrationWorker.bulk_perform_in` schedules all jobs for
|
|
# the same time, which is not helpful in most cases where we wish to
|
|
# spread the work over time.
|
|
BackgroundMigrationWorker.perform_in(delay_interval * index, job_class_name, [start_id, end_id])
|
|
end
|
|
end
|
|
|
|
# Fetches indexes on a column by name for postgres.
|
|
#
|
|
# This will include indexes using an expression on the column, for example:
|
|
# `CREATE INDEX CONCURRENTLY index_name ON table (LOWER(column));`
|
|
#
|
|
# For mysql, it falls back to the default ActiveRecord implementation that
|
|
# will not find custom indexes. But it will select by name without passing
|
|
# a column.
|
|
#
|
|
# We can remove this when upgrading to Rails 5 with an updated `index_exists?`:
|
|
# - https://github.com/rails/rails/commit/edc2b7718725016e988089b5fb6d6fb9d6e16882
|
|
#
|
|
# Or this can be removed when we no longer support postgres < 9.5, so we
|
|
# can use `CREATE INDEX IF NOT EXISTS`.
|
|
def index_exists_by_name?(table, index)
|
|
# We can't fall back to the normal `index_exists?` method because that
|
|
# does not find indexes without passing a column name.
|
|
if indexes(table).map(&:name).include?(index.to_s)
|
|
true
|
|
elsif Gitlab::Database.postgresql?
|
|
postgres_exists_by_name?(table, index)
|
|
else
|
|
false
|
|
end
|
|
end
|
|
|
|
def postgres_exists_by_name?(table, name)
|
|
index_sql = <<~SQL
|
|
SELECT COUNT(*)
|
|
FROM pg_index
|
|
JOIN pg_class i ON (indexrelid=i.oid)
|
|
JOIN pg_class t ON (indrelid=t.oid)
|
|
WHERE i.relname = '#{name}' AND t.relname = '#{table}'
|
|
SQL
|
|
|
|
connection.select_value(index_sql).to_i > 0
|
|
end
|
|
|
|
def mysql_compatible_index_length
|
|
Gitlab::Database.mysql? ? 20 : nil
|
|
end
|
|
end
|
|
end
|
|
end
|