fix: nested examples in OpenAPI schemas for request body & response

README.md

@@ -1000,7 +1000,7 @@ Will generate this in the OpenAPI v3 schema's `path`:
                   "foo": { "type": "string" },
                   "bar": { "type": "string" }
                 },
-                "examples": [{ "foo": "bar", "bar": "baz" }]
+                "example": { "foo": "bar", "bar": "baz" }
               }
             }
           },

lib/spec/openapi/utils.js

@@ -173,7 +173,7 @@ function plainJsonObjectToOpenapi3 (container, jsonSchema, externalSchemas, secu
           required: jsonSchemaElement.required
         }
 
-        const media = schemaToMedia(jsonSchemaElement)
+        const media = schemaToMedia(jsonSchemaElement, true)
 
         // complex serialization in query or cookie, eg. JSON
         // https://swagger.io/docs/specification/describing-parameters/#schema-vs-content
@@ -201,7 +201,7 @@ function plainJsonObjectToOpenapi3 (container, jsonSchema, externalSchemas, secu
       break
     case 'path':
       toOpenapiProp = function (propertyName, jsonSchemaElement) {
-        const media = schemaToMedia(jsonSchemaElement)
+        const media = schemaToMedia(jsonSchemaElement, true)
 
         const result = {
           ...media,
@@ -231,10 +231,10 @@ function plainJsonObjectToOpenapi3 (container, jsonSchema, externalSchemas, secu
     })
 }
 
-function schemaToMedia (schema) {
+function schemaToMedia (schema, allowsMultipleExamples) {
   const media = { schema }
 
-  if (schema.examples?.length === 1) {
+  if (schema.examples && (!allowsMultipleExamples || schema.examples.length === 1)) {
     media.example = schema.examples[0]
     delete schema.examples
   } else if (schema.examples?.length > 1) {
@@ -251,13 +251,33 @@ function schemaToMedia (schema) {
   return media
 }
 
+function schemaToMediaRecursive (schema, allowsMultipleExamples) {
+  if (schema.type === 'object' && schema.properties) {
+    for (const property in schema.properties) {
+      const media = schemaToMediaRecursive(schema.properties[property], false)
+      schema.properties[property] = media.schema
+      if (typeof media.example !== 'undefined') {
+        schema.properties[property].example = media.example
+      }
+    }
+  } else if (schema.type === 'array' && schema.items) {
+    const media = schemaToMediaRecursive(schema.items, false)
+    schema.items = media.schema
+    if (typeof media.example !== 'undefined') {
+      schema.items.example = media.example
+    }
+  }
+  const media = schemaToMedia(schema, allowsMultipleExamples)
+  return media
+}
+
 function resolveBodyParams (body, schema, consumes, ref) {
   const resolved = transformDefsToComponents(ref.resolve(schema))
   if ((Array.isArray(consumes) && consumes.length === 0) || consumes === undefined) {
     consumes = ['application/json']
   }
 
-  const media = schemaToMedia(resolved)
+  const media = schemaToMediaRecursive(resolved, true)
   consumes.forEach((consume) => {
     body.content[consume] = media
   })
@@ -346,7 +366,7 @@ function resolveResponse (fastifyResponseJson, produces, ref) {
 
         delete resolved[xResponseDescription]
 
-        const media = schemaToMedia(resolved)
+        const media = schemaToMediaRecursive(resolved, true)
 
         for (const produce of produces) {
           content[produce] = media