Fixes #29468 - Add default URL validator for plugins

URL settings are common and this moves it from a custom validator in the
Puppet module to a default. Also adds tests and ensures the dhcp and dns
libvirt providers use it too.

lib/proxy/default_plugin_validators.rb

@@ -1,5 +1,9 @@
 class Proxy::DefaultPluginValidators
   def self.validators
-    {:file_readable => ::Proxy::PluginValidators::FileReadable, :presence => ::Proxy::PluginValidators::Presence}
+    {
+      file_readable: ::Proxy::PluginValidators::FileReadable,
+      presence: ::Proxy::PluginValidators::Presence,
+      url: ::Proxy::PluginValidators::Url,
+    }
   end
 end

lib/proxy/plugin_validators.rb

@@ -42,4 +42,18 @@ def validate!(settings)
       true
     end
   end
+
+  class Url < Base
+    def validate!(settings)
+      setting_value = settings[@setting_name]
+      raise ::Proxy::Error::ConfigurationError, "Setting '#{@setting_name}' is expected to contain a url" if setting_value.to_s.empty?
+
+      parsed = URI.parse(setting_value)
+      raise ::Proxy::Error::ConfigurationError, "Setting '#{@setting_name}' is missing a scheme" if parsed.scheme.nil? || parsed.scheme.empty?
+
+      true
+    rescue URI::InvalidURIError
+      raise ::Proxy::Error::ConfigurationError.new("Setting '#{@setting_name}' contains an invalid url")
+    end
+  end
 end

modules/dhcp_libvirt/dhcp_libvirt_plugin.rb

@@ -4,6 +4,7 @@ class Plugin < ::Proxy::Provider
 
     requires :dhcp, ::Proxy::VERSION
     default_settings :url => "qemu:///system", :network => 'default'
+    validate :url, :url => true
 
     load_classes ::Proxy::DHCP::Libvirt::PluginConfiguration
     load_dependency_injection_wirings ::Proxy::DHCP::Libvirt::PluginConfiguration

modules/dns_libvirt/dns_libvirt_plugin.rb

@@ -5,6 +5,7 @@ class Plugin < ::Proxy::Provider
     requires :dns, ::Proxy::VERSION
 
     default_settings :url => "qemu:///system", :network => 'default'
+    validate :url, :url => true
 
     load_classes ::Proxy::Dns::Libvirt::PluginConfiguration
     load_dependency_injection_wirings ::Proxy::Dns::Libvirt::PluginConfiguration

modules/puppet_proxy_puppet_api/plugin_configuration.rb

@@ -7,7 +7,6 @@ def load_programmable_settings(settings)
     end
 
     def load_classes
-      require 'puppet_proxy_common/custom_validators'
       require 'puppet_proxy_common/errors'
       require 'puppet_proxy_common/environments_retriever_base'
       require 'puppet_proxy_common/environment'

modules/puppet_proxy_puppet_api/puppet_proxy_puppet_api.rb

@@ -1,3 +1,2 @@
-require 'puppet_proxy_common/custom_validators'
 require 'puppet_proxy_puppet_api/plugin_configuration'
 require 'puppet_proxy_puppet_api/puppet_proxy_puppet_api_plugin'

modules/puppet_proxy_puppet_api/puppet_proxy_puppet_api_plugin.rb

@@ -4,7 +4,6 @@ class Plugin < Proxy::Provider
 
     plugin :puppet_proxy_puppet_api, ::Proxy::VERSION
 
-    load_validators :url => ::Proxy::Puppet::Validators::UrlValidator
     load_programmable_settings ::Proxy::PuppetApi::PluginConfiguration
     load_classes ::Proxy::PuppetApi::PluginConfiguration
     load_dependency_injection_wirings ::Proxy::PuppetApi::PluginConfiguration

modules/puppetca_http_api/puppetca_http_api_plugin.rb

@@ -1,5 +1,3 @@
-require 'puppet_proxy_common/custom_validators'
-
 module ::Proxy
   module PuppetCa
     module PuppetcaHttpApi
@@ -8,7 +6,6 @@ class Plugin < ::Proxy::Provider
 
         default_settings :puppet_ssl_ca => '/etc/puppetlabs/puppet/ssl/certs/ca.pem'
 
-        load_validators :url => ::Proxy::Puppet::Validators::UrlValidator
         requires :puppetca, ::Proxy::VERSION
 
         validate :puppet_url, :url => true

test/plugins/validator_test.rb

@@ -91,3 +91,45 @@ def test_optional_parameter_without_a_value_fails_validation
     end
   end
 end
+
+class UrlValidatorTest < Test::Unit::TestCase
+  class UrlValidatorTestPlugin < ::Proxy::Plugin
+    default_settings :a_setting => 'http://example.com'
+  end
+
+  def test_required_parameter_with_a_value_passes_validation
+    assert ::Proxy::PluginValidators::Url.new(UrlValidatorTestPlugin, 'a_setting', nil, nil).validate!(:a_setting => 'http://example.com')
+  end
+
+  def test_empty_string_treated_as_missing_value
+    error = assert_raises ::Proxy::Error::ConfigurationError do
+      ::Proxy::PluginValidators::Url.new(UrlValidatorTestPlugin, 'a_setting', nil, nil).validate!(:a_setting => '')
+    end
+
+    assert_match(/expected to contain a url/, error.message)
+  end
+
+  def test_required_parameter_without_a_value_fails_validation
+    error = assert_raises ::Proxy::Error::ConfigurationError do
+      ::Proxy::PluginValidators::Url.new(UrlValidatorTestPlugin, 'a_setting', nil, nil).validate!(:a_setting => nil)
+    end
+
+    assert_match(/expected to contain a url/, error.message)
+  end
+
+  def test_required_parameter_without_scheme_fails_validation
+    error = assert_raises ::Proxy::Error::ConfigurationError do
+      ::Proxy::PluginValidators::Url.new(UrlValidatorTestPlugin, 'a_setting', nil, nil).validate!(:a_setting => 'example.com')
+    end
+
+    assert_match(/missing a scheme/, error.message)
+  end
+
+  def test_optional_parameter_without_a_value_fails_validation
+    error = assert_raises ::Proxy::Error::ConfigurationError do
+      ::Proxy::PluginValidators::Url.new(UrlValidatorTestPlugin, 'optional_setting', nil, nil).validate!(:optional_setting => nil)
+    end
+
+    assert_match(/expected to contain a url/, error.message)
+  end
+end