handle null opaqueref for relation

Author: MathieuRA

@xen-orchestra/xapi-generator/src/generators/base.ts

@@ -5,7 +5,11 @@ export const generateBase = () => {
 
   const branded = 'export type Branded<TBrand extends string, TType = string> = TType & { [__brand]: TBrand }'
 
-  return `${brand}\n\n${branded}\n`
+  const opaqueRefEnum = "export const OPAQUE_REF = { EMPTY: 'OpaqueRef:NULL' } as const"
+
+  const opaqueRefType = "export type OPAQUE_REF_NULL = typeof OPAQUE_REF['EMPTY']"
+
+  return `${brand}\n\n${branded}\n\n${opaqueRefEnum}\n\n${opaqueRefType}\n`
 }
 
 const baseCommand = new Command('base').description('Generate base types').action(async () => {

@xen-orchestra/xapi-generator/src/generators/record.ts

@@ -38,6 +38,8 @@ export const generateRecord = (item: XapiItem) => {
         t => t.transition === 'published' && VERSION_BY_CODE_NAME[t.release] === undefined
       )
     const isDeprecated = field.lifecycle.transitions.some(t => t.transition === 'deprecated')
+    const isEmptyOpaqueRef =
+      field.default === 'OpaqueRef:NULL' || (field.default === 'Null' && field.type.endsWith('ref'))
 
     function isAlwaysExisting() {
       if (!isPublished || isPublishedAfterDundee) {
@@ -51,6 +53,9 @@ export const generateRecord = (item: XapiItem) => {
     //   field.name === 'uuid' || field.type.endsWith(' set') || (isPublished && isFromRio && !isDeprecated && !isOptional)
 
     const result = [`  ${field.name}${isAlwaysExisting() ? '' : '?'}: ${toType(field.type)}`]
+    if (isEmptyOpaqueRef) {
+      result[0] = result[0].concat(' | OPAQUE_REF_NULL')
+    }
 
     if (isDeprecated) {
       result.unshift('  /** @deprecated */')