feat(json-schema): expose API that generates examples from JSON Schema (#9190)

This allows to use the samples API in a static way
without fully instantiating SwaggerUI.

Refs #9188

src/core/plugins/json-schema-5-samples/fn/get-yaml-sample-schema.js

@@ -0,0 +1,34 @@
+/**
+ * @prettier
+ */
+import YAML, { JSON_SCHEMA } from "js-yaml"
+
+const makeGetYamlSampleSchema =
+  (getSystem) => (schema, config, contentType, exampleOverride) => {
+    const { fn } = getSystem()
+    const jsonExample = fn.getJsonSampleSchema(
+      schema,
+      config,
+      contentType,
+      exampleOverride
+    )
+    let yamlString
+    try {
+      yamlString = YAML.dump(
+        YAML.load(jsonExample),
+        {
+          lineWidth: -1, // don't generate line folds
+        },
+        { schema: JSON_SCHEMA }
+      )
+      if (yamlString[yamlString.length - 1] === "\n") {
+        yamlString = yamlString.slice(0, yamlString.length - 1)
+      }
+    } catch (e) {
+      console.error(e)
+      return "error: could not generate yaml example"
+    }
+    return yamlString.replace(/\t/g, "  ")
+  }
+
+export default makeGetYamlSampleSchema