Add schema matcher for non response objects + use schema to test additional metrics compliance

spec/fixtures/api/schemas/prometheus/additional_metrics_query_result.json

+{
+  "items": {
+    "properties": {
+      "group": {
+        "type": "string"
+      },
+      "metrics": {
+        "items": {
+          "properties": {
+            "queries": {
+              "items": {
+                "properties": {
+                  "query_range": {
+                    "type": "string"
+                  },
+                  "query": {
+                    "type": "string"
+                  },
+                  "result": {
+                    "type": "any"
+                  }
+                },
+                "type": "object"
+              },
+              "type": "array"
+            },
+            "title": {
+              "type": "string"
+            },
+            "weight": {
+              "type": "integer"
+            },
+            "y_label": {
+              "type": "string"
+            }
+          },
+          "type": "object"
+        },
+        "required": [
+          "metrics",
+          "title",
+          "weight"
+        ],
+        "type": "array"
+      },
+      "priority": {
+        "type": "integer"
+      }
+    },
+    "type": "object"
+  },
+  "required": [
+    "group",
+    "priority",
+    "metrics"
+  ],
+  "type": "array"
+}
\ No newline at end of file

spec/support/api/schema_matcher.rb

+def schema_path(schema)
+  schema_directory = "#{Dir.pwd}/spec/fixtures/api/schemas"
+  "#{schema_directory}/#{schema}.json"
+end
+
 RSpec::Matchers.define :match_response_schema do |schema, **options|
   match do |response|
-    schema_directory = "#{Dir.pwd}/spec/fixtures/api/schemas"
-    schema_path = "#{schema_directory}/#{schema}.json"
+    JSON::Validator.validate!(schema_path(schema), response.body, options)
+  end
+end
 
-    JSON::Validator.validate!(schema_path, response.body, options)
+RSpec::Matchers.define :match_schema do |schema, **options|
+  match do |data|
+    JSON::Validator.validate!(schema_path(schema), data, options)
   end
 end

spec/support/prometheus/additional_metrics_shared_examples.rb

@@ -34,7 +34,7 @@ RSpec.shared_examples 'additional metrics query' do
             priority: 1,
             metrics: [
               {
-                title: 'title', weight: nil, y_label: 'Values', queries: [
+                title: 'title', weight: 1, y_label: 'Values', queries: [
                 { query_range: 'query_range_a', result: query_range_result },
                 { query_range: 'query_range_b', label: 'label', unit: 'unit', result: query_range_result }
               ]
@@ -43,6 +43,7 @@ RSpec.shared_examples 'additional metrics query' do
           }
         ]
 
+        expect(query_result).to match_schema('prometheus/additional_metrics_query_result')
         expect(query_result).to eq(expected)
       end
     end
@@ -66,53 +67,16 @@ RSpec.shared_examples 'additional metrics query' do
       end
 
       it 'return group data both queries' do
-        expected = [
-          {
-            group: 'group_a',
-            priority: 1,
-            metrics: [
-              {
-                title: 'title',
-                weight: nil,
-                y_label: 'Values',
-                queries: [
-                  {
-                    query_range: 'query_range_a',
-                    result: [
-                      {
-                        metric: {},
-                        values: [[1488758662.506, '0.00002996364761904785'], [1488758722.506, '0.00003090239047619091']]
-                      }
-                    ]
-                  }
-                ]
-              }
-            ]
-          },
-          {
-            group: 'group_b',
-            priority: 1,
-            metrics: [
-              {
-                title: 'title_b',
-                weight: nil,
-                y_label: 'Values',
-                queries: [
-                  {
-                    query_range: 'query_range_b', result: [
-                    {
-                      metric: {},
-                      values: [[1488758662.506, '0.00002996364761904785'], [1488758722.506, '0.00003090239047619091']]
-                    }
-                  ]
-                  }
-                ]
-              }
-            ]
-          }
-        ]
+        queries_with_result_a = { queries: [{ query_range: 'query_range_a', result: query_range_result }] }
+        queries_with_result_b = { queries: [{ query_range: 'query_range_b', result: query_range_result }] }
 
-        expect(query_result).to eq(expected)
+        expect(query_result).to match_schema('prometheus/additional_metrics_query_result')
+
+        expect(query_result.count).to eq(2)
+        expect(query_result).to all(satisfy { |r| r[:metrics].count == 1 })
+
+        expect(query_result[0][:metrics].first).to include(queries_with_result_a)
+        expect(query_result[1][:metrics].first).to include(queries_with_result_b)
       end
     end
 
@@ -123,27 +87,14 @@ RSpec.shared_examples 'additional metrics query' do
       end
 
       it 'return group data only for query with results' do
-        expected = [
-          {
-            group: 'group_a',
-            priority: 1,
-            metrics: [
-              {
-                title: 'title',
-                weight: nil,
-                y_label: 'Values',
-                queries: [
-                  {
-                    query_range: 'query_range_a',
-                    result: query_range_result
-                  }
-                ]
-              }
-            ]
-          }
-        ]
+        queries_with_result = { queries: [{ query_range: 'query_range_a', result: query_range_result }] }
 
-        expect(query_result).to eq(expected)
+        expect(query_result).to match_schema('prometheus/additional_metrics_query_result')
+
+        expect(query_result.count).to eq(1)
+        expect(query_result).to all(satisfy { |r| r[:metrics].count == 1 })
+
+        expect(query_result.first[:metrics].first).to include(queries_with_result)
       end
     end
   end

spec/support/prometheus/metric_builders.rb

@@ -9,7 +9,7 @@ module Prometheus
     end
 
     def simple_metric(title: 'title', required_metrics: [], queries: [simple_query])
-      Gitlab::Prometheus::Metric.new(title, required_metrics, nil, nil, queries)
+      Gitlab::Prometheus::Metric.new(title, required_metrics, 1, nil, queries)
     end
 
     def simple_metrics(added_metric_name: 'metric_a')