Stringify grouping key values in push client

CHANGELOG.md

@@ -9,6 +9,9 @@
     Previously, an error would be raised if you passed a symbol as the job name, which
     is inconsistent with how we handle label values in the rest of the client. This
     change converts the job name to a string before trying to use it.
+- [#297](https://github.com/prometheus/client_ruby/pull/297) Stringify grouping key
+    values in push client:
+    Same thing as #296, but for grouping key values.
 
 # 4.2.1 / 2023-08-04
 

lib/prometheus/client/push.rb

@@ -99,6 +99,8 @@ def build_path(job, grouping_key)
         end
 
         grouping_key.each do |label, value|
+          value = value.to_s
+
           if value.include?('/')
             encoded_value = Base64.urlsafe_encode64(value)
             path += "/#{label}@base64/#{encoded_value}"

spec/prometheus/client/push_spec.rb

@@ -101,6 +101,15 @@
       expect(push.path).to eql('/metrics/job/foo')
     end
 
+    it 'converts non-string grouping labels to strings' do
+      push = Prometheus::Client::Push.new(
+        job: 'test-job',
+        grouping_key: { foo: :bar, baz: :qux},
+      )
+
+      expect(push.path).to eql('/metrics/job/test-job/foo/bar/baz/qux')
+    end
+
     it 'encodes the job name in url-safe base64 if it contains `/`' do
       push = Prometheus::Client::Push.new(
         job: 'foo/test-job',