Shortcuts

The fast CLI also supports shortcuts which are mapping expressions starting with ..

Shortcuts can keep your abstract scripts organized. Let's say you want to create your own format sql and you'll run it very often. You can create a shortcut for it and just reuse as you need.

Format SQL

Let's say you want to format some sql, so, here are some possible syntax to get some formatted version of an inline code:

fast .format_sql "select * from tbl"

It should return "SELECT * FROM tbl" with all reserved keywords upcased. Even it's not mandatory, it makes it much clear to scan the text.

The second option is with a sql file.

fast .format_sql /path/to/my_file.sql

Both cases will just output in the command line and further commands can be combined to send it to another file.

Add the following script to your Fastfile to just get started:

Fast.shortcut :format_sql do
  require 'fast/sql'
  content = ARGV.last
  method = File.exist?(content) ? :parse_sql_file : :parse_sql
  ast = Fast.public_send(method, content)
  ast = ast.first if ast.is_a? Array

  output = Fast::SQL.replace('_', ast) do |root|
    sb = root.loc.expression.source_buffer
    sb.tokens.each do |token|
      if token.keyword_kind == :RESERVED_KEYWORD
        range = Fast::Source.range(sb, token.start, token.end)
        replace(range, range.source.upcase)
      end
    end
  end
  require 'fast/cli'
  puts Fast.highlight(output, sql: true)
end

Anonymize SQL

Read a full blog post about this shortcut.

# fast .anonymize_sql file.sql
Fast.shortcut :anonymize_sql do
  require 'fast/sql'
  file = ARGV.last
  ast = Fast.parse_sql_file(file)
  memo = {}

  relnames = search("(relname $_)", ast).grep(String).uniq
  pattern = "{relname (sval {#{relnames.map(&:inspect).join(' ')}})}"

  content = Fast::SQL.replace(pattern, ast) do |node|
    new_name = memo[node.source.tr(%|"'|, '')] ||= "x#{memo.size}"
    new_name = "'#{new_name}'" if node.type == :sval
    replace(node.loc.expression, new_name)
  end
  puts Fast.highlight(content, sql: true)
end

Check out the default shortcuts guide if you need more content about shortcuts.