go bindings for username lookup by UID

Makefile

@@ -3,8 +3,9 @@
 check_certificate_files := $(wildcard src/go/checkCertificate/*.go)
 check_certificate_signatures_files := $(wildcard src/go/checkCertSignatures/*.go)
 storage_files := $(wildcard src/go/storage/*.go)
+get_user_by_uid_files := $(wildcard src/go/getUserByUid/*.go)
 
-all: check_certificate check_cert_signatures storage typescript
+all: check_certificate check_cert_signatures storage getUserByUid typescript
 
 check_certificate: 
 	HOME=/root go build -ldflags="-s -w" -o dist/bin/checkCertificate ${check_certificate_files}
@@ -21,5 +22,10 @@ storage:
 	@chmod 740 dist/bin/storage
 	file dist/bin/storage
 
+getUserByUid:
+	HOME=/root go build -ldflags="-s -w" dist/bin/getUserByUid ${storage_files}
+	@chmod 740 dist/bin/getUserByUid
+	file dist/bin/getUserByUid
+
 typescript:
 	tsc -p ./tsconfig.json

src/functions/getUserByUid.ts

@@ -0,0 +1,7 @@
+import { Client } from '..';
+
+export default async function getUserByUid(client: Client, uid: number): Promise<string | null> {
+  const res = await client.util.exec(`${__dirname}/../bin/getUserByUid ${uid}`);
+  if (res === '-1') return null;
+  return res.trim();
+}

src/functions/index.ts

@@ -1,5 +1,6 @@
 export { default as checkLock, clear as clearLock } from '../intervals/checkLock';
 export { default as dataConversion } from './dataConversion';
 export { default as existingLimitsSetup } from './existingLimitsSetup';
+export { default as getUserByUid } from './getUserByUid';
 // export { default as checkSS, clear as clearSS } from './checkSS';
 export { default as parseCertificate, Certificate } from './parseCertificate';

src/go/getUserByUid/getUserByUid.go

@@ -0,0 +1,21 @@
+package main
+
+import (
+	"fmt"
+	"os"
+	"os/user"
+)
+
+func main() {
+	if len(os.Args) > 1 {
+		fmt.Println("-1")
+		os.Exit(0)
+	}
+	userInfo, err := user.LookupId(os.Args[1])
+	if err != nil {
+		fmt.Println("-1")
+		os.Exit(0)
+	}
+	fmt.Printf("%s", userInfo.Username)
+	os.Exit(0)
+}