Email validation in Ruby on Rails?
I use the constant built into URI in the standard ruby library
ruby-on-rails
How do I remove Permission denied @ rb_sysopen – Gem install error?
Its a permissions issue. You could fix it with this: or possibly in your case What does this do: This is telling the system to change the files to change the ownership to the current user. Something must have gotten messed up when something got installed. Usually this is because there are multiple accounts or … Read more
Cannot load such file — bcrypt_ext
I had a similar problem today with ruby 2.3.3 and rails 4.2.4. The problem was that bundle install of devise installed as a dependency another version of bcrypt (bcrypt (3.1.11 x86-mingw32) instead of bcrypt (3.1.11)) which was causing trouble with ruby 2.3 (it should work with all previous versions of ruby) The solution I used is to install bcrypt … Read more
Library not loaded: /usr/local/opt/readline/lib/libreadline.7.dylib
the error seems to be thrown when searching for /usr/local/opt/readline/lib/libreadline.7.dylib. Have you tried to symlink that? So something like: Just tried that on macOS Mojave, ruby 2.5.3p105 and Rails 5.2.2 and worked.
Unable to install gem – Failed to build gem native extension – cannot load such file — mkmf (LoadError)
There are similar questions: `require’: no such file to load — mkmf (LoadError) Failed to build gem native extension (mkmf (LoadError)) – Ubuntu 12.04 Usually, the solution is: sudo apt-get install ruby-dev Or, if that doesn’t work, depending on your ruby version, run something like: sudo apt-get install ruby1.9.1-dev Should fix your problem. Still not … Read more
What is the difference between Rails.cache.clear and rake tmp:cache:clear?
The rake task only clears out files that are stored on the filesystem in “#{Rails.root}/tmp/cache”. Here’s the code for that task. https://github.com/rails/rails/blob/ef5d85709d346e55827e88f53430a2cbe1e5fb9e/railties/lib/rails/tasks/tmp.rake#L25-L30 Rails.cache.clear will do different things depending on your apps setting for config.cache_store. http://guides.rubyonrails.org/caching_with_rails.html#cache-stores If you are using config.cache_store = :file_store then Rails.cache.clear will be functionally identical to rake tmp:cache:clear. However, if you’re using some other cache_store, like :memory_store or :mem_cache_store, then only Rails.cache.clear will clear your app cache. … Read more
Parsing XML with Ruby
As @pguardiario mentioned, Nokogiri is the de facto XML and HTML parsing library. If you wanted to print out the Id and Name values in your example, here is how you would do it: A few notes: at_xpath is for matching one thing. If you know you have multiple items, you want to use xpath instead. Depending on your document, namespaces can be problematic, … Read more
How to tell if homebrew is installed on Mac OS X
brew help. If brew is there, you get output. If not, you get ‘command not found’. If you need to check in a script, you can work out how to redirect output and check $?.
Using Pundit for all-access “super_admin” role
I’m wondering the best/simplest way to give a user “super_admin” access using the Pundit gem — or, what’s the simplest way to give a user access to all controller actions across the site? I realize I can edit the policy file for each controller, then add something like …to each and every action, in each … Read more
undefined method `each’ for nil:NilClass… why?
In your posts controller, you need to define @posts, which, based on the error you haven’t. As @posts is not defined calling each on it will generate undefined methodeach’ for nil:NilClass`.