diff --git a/lib/puppet/functions/encode_url_queries_for_python.rb b/lib/puppet/functions/encode_url_queries_for_python.rb
new file mode 100644
index 000000000..5c20b9885
--- /dev/null
+++ b/lib/puppet/functions/encode_url_queries_for_python.rb
@@ -0,0 +1,19 @@
+Puppet::Functions.create_function(:encode_url_queries_for_python) do
+
+  def encode_url_queries_for_python(*args)
+    require 'uri'
+
+    if (args.size != 1) then
+      raise Puppet::ParseError, 'encode_url_queries_for_python(): Wrong number of arguments'
+    end
+    queries = args[0]
+    if queries.class != Hash
+      raise Puppet::ParseError, "encode_url_queries_for_python(): Requires a Hash, got #{queries.class}"
+    end
+
+    if queries.empty?
+      return ''
+    end
+    return '?' + URI.encode_www_form(queries).gsub(/%/, '%%')
+  end
+end
diff --git a/manifests/migration/libvirt.pp b/manifests/migration/libvirt.pp
index de107bd3d..b450fa3eb 100644
--- a/manifests/migration/libvirt.pp
+++ b/manifests/migration/libvirt.pp
@@ -233,13 +233,7 @@ class nova::migration::libvirt(
       $postfix = ''
     }
 
-    if empty($client_extraparams) {
-      $extra_params =''
-    } else {
-      $extra_params_before_python_escape = join(uriescape(join_keys_to_values($client_extraparams, '=')), '&')
-      # Must escape % as nova interprets it incorrectly.
-      $extra_params = sprintf('?%s', regsubst($extra_params_before_python_escape, '%', '%%', 'G'))
-    }
+    $extra_params = encode_url_queries_for_python($client_extraparams)
 
     $live_migration_uri = "qemu+${transport}://${prefix}%s${postfix}/system${extra_params}"
 
diff --git a/spec/unit/functions/encode_url_queries_for_python_spec.rb b/spec/unit/functions/encode_url_queries_for_python_spec.rb
new file mode 100644
index 000000000..39df9c979
--- /dev/null
+++ b/spec/unit/functions/encode_url_queries_for_python_spec.rb
@@ -0,0 +1,9 @@
+require 'spec_helper'
+require 'puppet'
+
+describe 'encode_url_queries_for_python', :type => :puppet_function do
+
+  it { is_expected.to run.with_params({}).and_return('') }
+  it { is_expected.to run.with_params({'a' => 1, 'b' => 2}).and_return('?a=1&b=2') }
+  it { is_expected.to run.with_params({'a' => 'b%c'}).and_return('?a=b%%25c') }
+end