Ruby dynamic Regex condition

Question

I would like make a regex on controller (RoR). i have tried this code :

  @widget_check = ClanTemplatesWidget.find(params[:id])
  unless params[:config].blank?
    #@widget_check.config in database value = [{"input":"string","name":"code", "label":"Code clan","validation":"^([#][A-Z0-9]{7})$"}]
    JSON.parse(@widget_check.config).each do |config,i|
     regexp = Regexp.new(config["validation"])
     if regexp.match(params[:config][config["name"]])
       @error = 0
     else
       @error = 1
     end
    end
    @widget.config = params[:config].to_json
  end

For information my data is on the database. If i inspect the two params i have that :

config["validation"] = /^([#][A-Z0-9]{8})$/

params[:config][config["name"]] = #2YL9GR9R

If i rewrite my code with the data it's work fine (like that) :

if /^([#][A-Z0-9]{8})$/.match("#2YL9GR9R")
  @error = 0
else
  @error = 1
end

Since #2YL9GR9R doesn't have quotes, I would guess that both values (params[:config][config["name"]] and config["validation"]) are in fact strings. — Stefan
– Stefan, Commented Oct 12, 2016 at 6:58
You are saving your config values in a database, right? But how / where do you set the config variable / hash? You have to somehow retrieve the values from the database and assign them to config. — Stefan
– Stefan, Commented Oct 12, 2016 at 8:27

spickermann · Accepted Answer · 2016-10-12 06:59:12Z

3

Your config["validation"] contains a string that looks like a regexp, but it is not. But you can build a regexp out of a string:

regexp = Regexp.new(config["validation"])
regexp.match(params[:config][config["name"]])

Since Regexp.new expects a string without the surrounding /.../, you just might want to omit them.

answered Oct 12, 2016 at 6:59

spickermann

108k9 gold badges115 silver badges147 bronze badges

Sign up to request clarification or add additional context in comments.

12 Comments

Stefan Over a year ago

Or you could use params[:config][config["name"]].match(config["validation"]) – String#match implicitly converts the argument to a Regexp. (the surrounding /.../ must be removed in either case)

Shinix Over a year ago

Thank you for your answer, i've tried your code but still not working.

Stefan Over a year ago

@Shinix did you remove the leading and trailing /? You have to store "^([#][A-Z0-9]{7})$" instead of "/^([#][A-Z0-9]{7})$/"

Shinix Over a year ago

Yes, i've tried without / (i've update the code on my first post). If i use config data it's not working but if i use text like that it's work :/ regexp = Regexp.new("/^([#][A-Z0-9]{8})$/") regexp.match("#2YL9GR9R")

Stefan Over a year ago

@Shinix double check (within your code) if config["validation"] == "^([#][A-Z0-9]{8})$" and if params[:config][config["name"]] == "#2YL9GR9R". If they don't match, print both values via p value or puts value.inspect. Maybe there's a trailing newline or another minor difference.

|

Collectives™ on Stack Overflow

Ruby dynamic Regex condition

1 Answer 1

12 Comments

Your Answer

Hot Network Questions

Collectives™ on Stack Overflow

1 Answer 1

12 Comments

Your Answer

Sign up or log in

Post as a guest

Related