ruby-pg connection retry from PG::UnableToSend

gistfile1.rb

uri = URI.parse(ENV['POSTGRES_URL'])

$query_postgres = lambda do |sql|
  begin
    $postgres ||= PG.connect(uri.hostname, uri.port, nil, nil, uri.path[1..-1], uri.user, uri.password)
    $postgres.exec(sql)
  rescue PG::UnableToSend
    $postgres = nil
    retry
  end
end

result = $query_postgres.call("SELECT * FROM accounts")
result.each do |row|
  row.each do |key, value|
    puts [key, value].join("=")
  end
end