2 files changed, 26 insertions, 1 deletions

diff --git a/server/helpers/custom-validators/activitypub/actor.ts b/server/helpers/custom-validators/activitypub/actor.ts
index 77c003cdf..070632a20 100644
--- a/server/helpers/custom-validators/activitypub/actor.ts
+++ b/server/helpers/custom-validators/activitypub/actor.ts
@@ -27,7 +27,8 @@ function isActorPublicKeyValid (publicKey: string) {
     validator.isLength(publicKey, CONSTRAINTS_FIELDS.ACTORS.PUBLIC_KEY)
 }
 
-const actorNameRegExp = new RegExp('^[ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789\\-_\.]+$')
+const actorNameAlphabet = '[ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789\\-_.]'
+const actorNameRegExp = new RegExp(`^${actorNameAlphabet}+$`)
 function isActorPreferredUsernameValid (preferredUsername: string) {
   return exists(preferredUsername) && validator.matches(preferredUsername, actorNameRegExp)
 }
@@ -127,6 +128,7 @@ function areValidActorHandles (handles: string[]) {
 
 export {
   normalizeActor,
+  actorNameAlphabet,
   areValidActorHandles,
   isActorEndpointsObjectValid,
   isActorPublicKeyObjectValid,
diff --git a/server/helpers/regexp.ts b/server/helpers/regexp.ts
new file mode 100644
index 000000000..2336654b0
--- /dev/null
+++ b/server/helpers/regexp.ts
@@ -0,0 +1,23 @@
+// Thanks to https://regex101.com
+function regexpCapture (str: string, regex: RegExp, maxIterations = 100) {
+  let m: RegExpExecArray
+  let i = 0
+  let result: RegExpExecArray[] = []
+
+  // tslint:disable:no-conditional-assignment
+  while ((m = regex.exec(str)) !== null && i < maxIterations) {
+    // This is necessary to avoid infinite loops with zero-width matches
+    if (m.index === regex.lastIndex) {
+      regex.lastIndex++
+    }
+
+    result.push(m)
+    i++
+  }
+
+  return result
+}
+
+export {
+  regexpCapture
+}