Module: PgSqlTriggers::EventsChecksum

Defined in:
lib/pg_sql_triggers/events_checksum.rb

Overview

Normalizes trigger event lists (including PostgreSQL UPDATE OF col1, col2) for checksums so TriggerRegistry#calculate_checksum, Registry::Manager.calculate_checksum, and Drift::Detector.calculate_db_checksum stay aligned.

Class Method Summary collapse

Class Method Details

.build_tokens(events, sorted_lowercase_columns) ⇒ Object 



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# File 'lib/pg_sql_triggers/events_checksum.rb', line 65

def build_tokens(events, sorted_lowercase_columns)
  cols_join = sorted_lowercase_columns.join(",")
  events.map do |ev|
    if ev == "update" && cols_join.present?
      "update:#{cols_join}"
    else
      ev
    end
  end
end

.canonical_from_definition(defn) ⇒ String

Returns canonical token string, or empty when events is missing/empty.

Parameters:

  • defn (Hash) —

    parsed registry definition JSON (string or symbol keys)

Returns:

  • (String) —

    canonical token string, or empty when events is missing/empty



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# File 'lib/pg_sql_triggers/events_checksum.rb', line 12

def canonical_from_definition(defn)
  hash = stringify(defn)
  events = Array(hash["events"]).map(&:to_s).map(&:downcase)
  return "" if events.empty?

  columns = normalized_columns(hash["columns"])
  build_tokens(events, columns).sort.join("|")
end

.canonical_from_pg_triggerdef(trigger_def) ⇒ Object

Parameters:

  • trigger_def (String) —

    pg_get_triggerdef output



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# File 'lib/pg_sql_triggers/events_checksum.rb', line 31

def canonical_from_pg_triggerdef(trigger_def)
  return "" if trigger_def.blank?

  clause = extract_events_clause(trigger_def)
  return "" if clause.blank?

  parse_events_clause(clause).sort.join("|")
end

.events_sql_fragment(defn, quote_column:) ⇒ Object

SQL fragment for the event list (e.g. INSERT OR UPDATE OF “email”), preserving DSL event order.



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# File 'lib/pg_sql_triggers/events_checksum.rb', line 41

def events_sql_fragment(defn, quote_column:)
  hash = stringify(defn)
  events = Array(hash["events"]).map(&:to_s).map(&:downcase)
  columns = ordered_columns(hash["columns"])
  return "INSERT" if events.empty?

  events.map do |ev|
    if ev == "update" && columns.any?
      quoted = columns.map { |c| quote_column.call(c) }.join(", ")
      "UPDATE OF #{quoted}"
    else
      ev.upcase
    end
  end.join(" OR ")
end

.extract_events_clause(trigger_def) ⇒ Object 



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# File 'lib/pg_sql_triggers/events_checksum.rb', line 76

def extract_events_clause(trigger_def)
  s = trigger_def.to_s.squish
  m = s.match(/(?:BEFORE|AFTER|INSTEAD\s+OF)\s+(.+?)\s+ON\s+/i)
  return "" unless m

  m.captures.first.to_s.strip
end

.normalize_pg_identifier(fragment) ⇒ Object 



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# File 'lib/pg_sql_triggers/events_checksum.rb', line 99

def normalize_pg_identifier(fragment)
  f = fragment.to_s.strip
  if f.start_with?('"') && f.end_with?('"') && f.length >= 2
    f[1...-1].gsub('""', '"').downcase
  else
    f.downcase
  end
end

.normalized_columns(raw) ⇒ Object 



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# File 'lib/pg_sql_triggers/events_checksum.rb', line 57

def normalized_columns(raw)
  ordered_columns(raw).map(&:downcase).sort
end

.ordered_columns(raw) ⇒ Object 



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# File 'lib/pg_sql_triggers/events_checksum.rb', line 61

def ordered_columns(raw)
  Array(raw).flatten.compact.map { |c| c.to_s.strip }.reject(&:empty?)
end

.parse_events_clause(clause) ⇒ Object 



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# File 'lib/pg_sql_triggers/events_checksum.rb', line 84

def parse_events_clause(clause)
  clause.split(/\s+OR\s+/i).filter_map do |part|
    part = part.strip
    next if part.empty?

    um = part.match(/\AUPDATE\s+OF\s+(.+)\z/i)
    if um
      cols = um[1].split(",").map { |c| normalize_pg_identifier(c) }.sort
      "update:#{cols.join(',')}"
    else
      part.downcase
    end
  end
end

.segment_from_definition_json(definition_json) ⇒ Object

Parameters:

  • definition_json (String, nil) 


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# File 'lib/pg_sql_triggers/events_checksum.rb', line 22

def segment_from_definition_json(definition_json)
  return "" if definition_json.blank?

  canonical_from_definition(JSON.parse(definition_json))
rescue JSON::ParserError
  ""
end

.stringify(defn) ⇒ Object 



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# File 'lib/pg_sql_triggers/events_checksum.rb', line 108

def stringify(defn)
  return {} if defn.nil?

  defn.transform_keys(&:to_s)
end