Add a function to generate the doc

src/doc.ts

@@ -0,0 +1,40 @@
+import * as yup from 'yup'
+
+type DocElement = {
+  name: string
+  required: boolean
+  default_value?: unknown
+}
+
+export function doc<S extends yup.Maybe<yup.AnyObject>>(
+  scheme: yup.ObjectSchema<S>,
+  base_name: string = ''
+): DocElement[] {
+  if (base_name.length !== 0) base_name = base_name + '_'
+
+  let elements: DocElement[] = []
+
+  for (const key in scheme.fields) {
+    const sub_key = base_name + key.toUpperCase()
+    const sub_scheme = scheme.fields[key] as yup.AnySchema
+    const type = sub_scheme.describe().type
+
+    if (type === 'object') {
+      const sub_elements = doc(sub_scheme as yup.ObjectSchema<S>, sub_key)
+      elements = [...elements, ...sub_elements]
+    } else {
+      elements.push(generic(sub_scheme, sub_key))
+    }
+  }
+
+  return elements
+}
+
+function generic(scheme: yup.AnySchema, name: string): DocElement {
+  const default_value = scheme.getDefault()
+  return {
+    name,
+    required: !scheme.spec.optional,
+    default_value
+  }
+}

src/index.ts

@@ -1,2 +1,3 @@
 export * as yup from 'yup'
 export {parse} from './parsing'
+export {doc} from './doc'