Sinatra: Could not find gem 'rack-protection (~> 2.0)', which is required by gem 'sinatra', in any of the sources.

[salmagomaa]

I was working with sinatra master since my upgrading to Rails 5, but today it seems there are some updates to the master, that throws the following error when I am trying to update the bundle.

The thrown error is:

Bundler could not find compatible versions for gem "rack-protection":
In Gemfile:
sinatra was resolved to 2.0.0.pre.alpha, which depends on
rack-protection (~> 2.0)

Could not find gem 'rack-protection (~> 2.0)', which is required by gem
'sinatra', in any of the sources.

Any help please?

[tloszko]

Use github's version:

gem "rack-protection", :github => "sinatra/rack-protection"

[salmagomaa]

Thanks a million! It works for me.

[Rim-777]

For rails 6 helped to set the gem globally
gem install "rack-protection"