如何使用Ruby在YAML中逃避花括号和反斜杠？

Question

My app validates and imports data files for various vendors. One of the validations on the file will be to check whether it's filename is in the right format. I have my regex stored in my YAML file along with various other configurations as follows -

---
filename_regex: !ruby/regexp '/^input_.{1,10}_company_\d{8}.tsv$/'
check_header_row: true
foo: "Bar"
....

Essentially the above enforces that it has to be of format: input_companyName_company_20141127.tst . I'm loading the file with YAML.load(filename) in the app.

I'm running into 2 problems, as you may have already guessed

1. The curly braces don't escape correctly. When I take them out it works fine, so those are almost certainly the problem. Apparently \\ doesn't work for escaping, and neither does ' ?

2. The \\d needs to have it's own backslash escaped, I assume? In that case would I use \\\\d in the file? That didn't seem to work either.

Thanks!

Answer 1

I can't seem to replicate any problem with what you already have.

Don't forget you probably want to be escaping the . at the end for .tsv and as someone already mentioned use \\A and \\Z instead of ^ and $ like '/\\Ainput_.{1,10}_company_\\d{8}\\.tsv\\Z/'

regex.yml

---
filename_regex: !ruby/regexp '/^input_.{1,10}_company_\d{8}.tsv$/'
foo: 'bar'
---

regex.rb

require 'yaml'

cfg = YAML.load_file('regex.yml')

valid_test_name = 'input_ABCD_company_12345678.tsv'
invalid_company_test_name = 'input_CompanyTooLong_company_12345678.tsv'
invalid_date_test_name = 'input_Company_company_12345678901.tsv'

valid_pass = valid_test_name =~ cfg["filename_regex"] ? 'pass' : 'fail'
invalid_company_pass = invalid_date_test_name =~ cfg["filename_regex"] ? 'pass' : 'fail'
invalid_date_pass = invalid_date_test_name =~ cfg["filename_regex"] ? 'pass' : 'fail'

puts "#{valid_test_name}: #{valid_pass}"
puts "#{invalid_company_test_name}: #{invalid_company_pass}"
puts "#{invalid_date_test_name}: #{invalid_date_pass}"

Running it ruby regex.rb outputs

input_ABCD_company_12345678.tsv: pass
input_CompanyTooLong_company_12345678.tsv: fail
input_Company_company_12345678901.tsv: fail