Merge pull request #45 from BrNi05/41-feature-expose-backend-error-msg-consts-so-ebs-can-use-them

Expose errors msgs for EBs

Author: BrNi05

package-lock.json

@@ -1,6 +1,6 @@
 {
   "name": "discos",
-  "version": "1.1.5",
+  "version": "1.1.6",
   "main": "dist/index.js",
   "types": "dist/index.d.ts",
   "type": "module",

package.json

@@ -1,5 +1,5 @@
 // Platform validation
-export const PLATFORM_ERR = 'DiscOS CRITICAL ERROR: Only Linux is supported. Startup aborted.';
+export const PLATFORM_ERR = 'DiscOS ERROR: Only Linux is supported. Startup aborted.';
 
 // dotenv validation
 export function ENV_MISSING_VAR(missingVars: string[]): string {
@@ -20,8 +20,8 @@ export const ENV_QUICK_VIEW_MAX_LENGTH = 'DiscOS ERROR: QUICK_VIEW_MAX_LENGTH mu
 // DB validation
 export const DB_ERR = 'DiscOS ERROR: Database file is invalid or missing.';
 export const DB_USER_ERR = 'DiscOS ERROR: users must be an object with numeric string keys (Discord UIDs) and string values (local users).';
-export const DB_USERS_EMPTY = 'DiscOS WARN: No users found in database.';
-export const DB_USERS_INVALID = 'User IDs must be numeric strings at least 17 characters long.';
+export const DB_USERS_EMPTY = 'DiscOS ERROR: No users found in database.';
+export const DB_USERS_INVALID = 'DiscOS ERROR: User IDs must be numeric strings at least 17 characters long.';
 export const DB_ADMIN_ERR = 'DiscOS ERROR: adminUsers must be an array of numeric strings with at least 17 characters.';
 export const DB_NO_ADMIN = 'DiscOS ERROR: There must be at least one admin user in the database.';
 export const DB_ADMIN_INVALID = 'DiscOS ERROR: adminUsers must be a non-empty array of numeric strings with at least 17 characters.';
@@ -329,15 +329,20 @@ export function ADMIN_GOODBYE(user: string): string {
 export const UNAME_PREFIX = 'discos';
 
 // Backend
-export const SPAWN_ERR = 'DiscOS CRITICAL ERROR: cmdex is broken.';
-export const DIR_ERR = 'The provided path is an existing directory.';
-export const PERM_ERR = 'No permission to write to the file (or to enter the directories).';
-export const DOWNLOAD_ERR = 'Failed to download file from Discord CDN.';
-export const SET_PERM_ERR = 'Failed to set file permissions.';
+export const SPAWN_ERR = 'DiscOS ERROR: cmdex is broken.';
+export const EB_DIR_ERR = 'The provided path is an existing directory.';
+export const EB_PERM_ERR = 'No permission to write to the file (or to enter the directories).';
+export const EB_DOWNLOAD_ERR = 'Failed to download file from Discord CDN.';
+export const EB_SET_PERM_ERR = 'Failed to set file permissions.';
 
 export const PING_FAILED = 'Ping failed: ';
 export const EXTERNAL_OK = 'External backend is online and responded to the health check ping.';
 export const EXTERNAL_NORESPONSE =
   'WARNING! The external backend did not respond to the health check ping. It may be offline or unreachable.';
 
 export const NETWORK_ERR = 'DiscOS ERROR: Network error while trying to connect to the backend.';
+
+// External backend specific
+export const EB_DB_ERR = 'DiscOS has encountered a critical error. Please contact the administrator.';
+export const EB_PAYLOAD_INVALID = 'DiscOS ERROR: Payload validation failed.';
+export const EB_GENERIC_ERR = 'DiscOS has encountered an unknown error. Failed to execute command.';

src/common.ts

@@ -10,3 +10,6 @@ export const PING_RESPONSE: string = 'DISCOS';
 // Database update dummy command
 // The suffix added to the backend URL when updating the database
 export const DB_UPDATE: string = 'dbupdate';
+
+// External backend error messages
+export { EB_DB_ERR, EB_PAYLOAD_INVALID, EB_GENERIC_ERR, EB_DIR_ERR, EB_PERM_ERR, EB_DOWNLOAD_ERR, EB_SET_PERM_ERR } from '../common.js';

src/shared/consts.ts

@@ -29,20 +29,24 @@ const execAsync = promisify(exec);
 
 // Determines local user (based on Discord UID)
 async function localUser(user: string): Promise<string> {
-  // Handle root user (for admos root <command>)
-  if (user === ROOT_UID) {
-    return 'root';
-  }
+  try {
+    // Handle root user (for admos root <command>)
+    if (user === ROOT_UID) {
+      return 'root';
+    }
 
-  const dbContent: string = await readFile(Config.databasePath, 'utf-8');
-  const dbParsed = JSON.parse(dbContent) as {
-    users: Record<string, string>;
-  };
+    const dbContent: string = await readFile(Config.databasePath, 'utf-8');
+    const dbParsed = JSON.parse(dbContent) as {
+      users: Record<string, string>;
+    };
 
-  // Cannot be null, since only an allowedUser can send commands
-  const serverUser: string = dbParsed.users[user];
+    // Cannot be null, since only an allowedUser can send commands
+    const serverUser: string = dbParsed.users[user];
 
-  return shellEscape([serverUser]);
+    return shellEscape([serverUser]);
+  } catch {
+    return '.'; // Silently fail (cmd exec will return an error), but encountering such an error is basically impossible
+  }
 }
 
 // Axios response creation
@@ -98,21 +102,21 @@ async function fileWrite(url: string, path: string, payload: ICommandQueueItem):
   const isDirCmd = shellEscape([`[ -d ${escapedPath} ] && echo 1 || echo 0`]);
   let { stdout } = await execAsync(`sudo /usr/local/bin/cmdex ${serverUser} ${isDirCmd}`);
   if (stdout.trim() === '1') {
-    return COMMON.DIR_ERR;
+    return COMMON.EB_DIR_ERR;
   }
 
   // Test if the user has permission to write to the file (while creating the neccessary directories)
   const testPermissionCmd = shellEscape([`mkdir -p "$(dirname ${escapedPath})" && echo > ${escapedPath} && rm -f ${escapedPath}`]);
   ({ stdout } = await execAsync(`sudo /usr/local/bin/cmdex ${serverUser} ${testPermissionCmd}`));
   if (stdout.trim() !== '') {
-    return COMMON.PERM_ERR;
+    return COMMON.EB_PERM_ERR;
   }
 
   // Download the file from Discord CDN
   const curlCmd = shellEscape([`curl -fsSL ${safeUrl} -o ${escapedPath}`]);
   ({ stdout } = await execAsync(`sudo /usr/local/bin/cmdex ${serverUser} ${curlCmd}`));
   if (stdout.trim() !== '') {
-    return COMMON.DOWNLOAD_ERR;
+    return COMMON.EB_DOWNLOAD_ERR;
   }
 
   // Set the file permissions to 660
@@ -123,7 +127,7 @@ async function fileWrite(url: string, path: string, payload: ICommandQueueItem):
   const permCmd = shellEscape([`cd ${userHomeDir} && chown ${serverUser}:${serverUser} ${escapedPath} && chmod 644 ${escapedPath}`]);
   ({ stdout } = await execAsync(`sudo /usr/local/bin/cmdex root ${permCmd}`));
   if (stdout.trim() !== '') {
-    return COMMON.SET_PERM_ERR;
+    return COMMON.EB_SET_PERM_ERR;
   }
 
   return WRITE_OP_SUCCESS;