Class: PgCanary::Rules::SelectStarWithHeavyColumns

Inherits:
Base
  • Object
show all
Defined in:
lib/pg_canary/rules/definitions/select_star_with_heavy_columns.rb

Overview

SELECT * (ActiveRecord's default) on a table that has heavy columns (bytea / text / jsonb) transfers those payloads on every query. Whether that matters depends on the data, hence opt-in. Heavy types: config.rules.select_star_with_heavy_columns.heavy_types.

Instance Method Summary collapse

Methods inherited from Base

all, check, default_enabled, enabled?, #initialize, option, options, rule_name

Constructor Details

This class inherits a constructor from PgCanary::Rules::Base

Instance Method Details

#check ⇒ Object 



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# File 'lib/pg_canary/rules/definitions/select_star_with_heavy_columns.rb', line 15

def check
  heavy_types = rule_config.heavy_types
  detections = []
  each_scope do |scope|
    star_tables(scope).each do |table|
      next unless applicable_table?(table)

      heavy = column_types(table).select { |_, type| heavy_types.include?(type) }.keys
      next if heavy.empty?

      detections << detection(
        table: table,
        columns: heavy,
        message: "SELECT * on #{table} transfers its heavy columns (#{heavy.join(", ")}) " \
                 "on every query.",
        suggestion: "Select only the columns you need (.select(:id, ...)), or move large " \
                    "payloads to a separate table loaded on demand."
      )
    end
  end
  detections
end