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server/helpers/custom-validators/webfinger.ts

@@ -0,0 +1,25 @@
+import 'express-validator'
+import 'multer'
+import { CONFIG } from '../../initializers/constants'
+import { exists } from './misc'
+
+function isWebfingerResourceValid (value: string) {
+  if (!exists(value)) return false
+  if (value.startsWith('acct:') === false) return false
+
+  const accountWithHost = value.substr(5)
+  const accountParts = accountWithHost.split('@')
+  if (accountParts.length !== 2) return false
+
+  const host = accountParts[1]
+
+  if (host !== CONFIG.WEBSERVER.HOST) return false
+
+  return true
+}
+
+// ---------------------------------------------------------------------------
+
+export {
+  isWebfingerResourceValid
+}