Allow non-string Resource label values. (#180)

Fixes #158.

Co-authored-by: Matthew Wear <[email protected]>

sdk/lib/opentelemetry/sdk/resources/resource.rb

@@ -15,15 +15,16 @@ class << self
 
           # Returns a newly created {Resource} with the specified labels
           #
-          # @param [Hash<String, String>] labels Hash of key-value pairs to be used
+          # @param [Hash{String => String, Numeric, Boolean} labels Hash of key-value pairs to be used
           #   as labels for this resource
           # @raise [ArgumentError] If label keys and values are not strings
           # @return [Resource]
           def create(labels = {})
             frozen_labels = labels.each_with_object({}) do |(k, v), memo|
-              raise ArgumentError, 'label keys and values must be strings' unless k.is_a?(String) && v.is_a?(String)
+              raise ArgumentError, 'label keys must be strings' unless k.is_a?(String)
+              raise ArgumentError, 'label values must be strings, integers, floats, or booleans' unless Internal.valid_value?(v)
 
-              memo[-k] = -v
+              memo[-k] = v.freeze
             end.freeze
 
             new(frozen_labels)

sdk/test/opentelemetry/sdk/resources/resource_test.rb

@@ -31,8 +31,13 @@
       _(proc { Resource.create(k1: 'v1') }).must_raise(ArgumentError)
     end
 
-    it 'enforces values are strings' do
+    it 'enforces values are strings, ints, floats, or booleans' do
       _(proc { Resource.create('k1' => :v1) }).must_raise(ArgumentError)
+      values = ['v1', 123, 456.78, false, true]
+      values.each do |value|
+        resource = Resource.create('k1' => value)
+        _(resource.label_enumerator.first.last).must_equal(value)
+      end
     end
   end