Question

Suppose that after primitive validation of user submitted URL I have the string that looks like URL:

url = 'http://www.thisdomaindoesntexist.com/dont_even_ask_about/this/uri'

How can I check if its available or not?

I tried this in my is_valid_link function:

require "net/http"
url = URI.parse(url)
req = Net::HTTP.new(url.host, url.port)
res = req.request_head(url.path)

It works if the server exists giving me back the HTTP response, but the problem is that in case of bad url I get an error like this:

SocketError in PostsController#create

getaddrinfo: nodename nor servname provided, or not known

How should I do this kind of validation properly?

Thanks in advance.

Answer 1

You can use rescue to catch errors and do some error handling

begin
  require "net/http"
  url = URI.parse(url)
  req = Net::HTTP.new(url.host, url.port)
  res = req.request_head(url.path)
rescue
  # error occured, return false
  false
else
  # valid site
  true
end

Use rescue inline:

require "net/http"
url = URI.parse(url)
req = Net::HTTP.new(url.host, url.port)
res = req.request_head(url.path) rescue false