move some code into functions

Signed-off-by: coolguy284 <coolguy284v64@gmail.com>

README.md

@@ -0,0 +1,23 @@
+# Hash Backup Tool
+
+This program is used to create backups of a given folder tree by referencing each file by its hash. Each additional backup to the same backup dir will only add new files that have a different hash, so space is conserved. All file timestamps made available in node.js are preserved.
+
+# Usage
+
+Download `hash_backup.js` and place anywhere. Run `node hash_backup.js` to see help.
+
+## Help
+
+```
+Node Hash Backup Tool
+
+Usage: node hash_backup.js [command] [arguments]
+
+Command `init`:
+  Usage: node hash_backup.js init <backupDir>
+  Initalizes empty hash backup in backup dir.
+
+Command `delete`:
+  Usage: node hash_backup.js delete <backupDir>
+  Removes all files at hash backup dir.
+```

hash_backup.js

@@ -30,6 +30,54 @@ async function getAllFilesInDir(path, excludeDirs) {
   return entries;
 }
 
+async function _checkBackupDirIsDir(path) {
+  let backupDirStats;
+  try {
+    backupDirStats = await fs.promises.stat(path);
+  } catch (e) {
+    if (e.code != 'ENOENT') throw e;
+  }
+
+  if (backupDirStats == null)
+    throw new Error(`Error: ${path} does not exist.`);
+
+  if (!backupDirStats.isDirectory())
+    throw new Error(`Error: ${path} not a directory.`);
+}
+
+async function initBackupDir(opts) {
+  if (typeof opts != 'object') opts = {};
+
+  let performChecks = typeof opts.performChecks == 'boolean' ? opts.performChecks : true;
+  let backupDir = typeof opts.backupDir == 'string' && opts.backupDir != '' ? opts.backupDir : '.';
+
+  if (performChecks) {
+    _checkBackupDirIsDir(backupDir);
+
+    if ((await fs.promises.readdir(backupDir)).length != 0)
+      throw new Error(`Error: ${backupDir} already has files in it.`);
+  }
+
+  await fs.promises.mkdir(path.join(backupDir, 'files'));
+}
+
+async function deleteBackupDir(opts) {
+  if (typeof opts != 'object') opts = {};
+
+  let performChecks = typeof opts.performChecks == 'boolean' ? opts.performChecks : true;
+  let backupDir = typeof opts.backupDir == 'string' && opts.backupDir != '' ? opts.backupDir : '.';
+
+  if (performChecks)
+    _checkBackupDirIsDir(backupDir);
+
+  let backupDirContents = Array.isArray(opts._backupDirContents) ?
+    opts._backupDirContents :
+    await fs.promises.readdir(backupDir, { withFileTypes: true });
+
+  for (let backupDirContent of backupDirContents)
+    await fs.promises.rm(path.join(backupDir, backupDirContent.name), { recursive: true });
+}
+
 async function runIfMain() {
   let argvSliced = process.argv.slice(2);
 
@@ -41,11 +89,11 @@ async function runIfMain() {
       '\n' +
       'Command `init`:\n' +
       '  Usage: node hash_backup.js init <backupDir>\n' +
-      '  Initalizes empty hash backup in backup dir\n' +
+      '  Initalizes empty hash backup in backup dir.\n' +
       '\n' +
       'Command `delete`:\n' +
       '  Usage: node hash_backup.js delete <backupDir>\n' +
-      '  Removes hash backup at backup dir'
+      '  Removes hash backup at backup dir.'
     );
   } else {
     let commandArgs = argvSliced.slice(1);
@@ -56,22 +104,7 @@ async function runIfMain() {
 
         if (backupDir == null || backupDir == '') backupDir = '.';
 
-        let backupDirStats;
-        try {
-          backupDirStats = await fs.promises.stat(backupDir);
-        } catch (e) {
-          if (e.code != 'ENOENT') throw e;
-        }
-
-        if (backupDirStats == null) {
-          console.log(`Error: ${backupDir} does not exist.`);
-          return;
-        }
-
-        if (!backupDirStats.isDirectory()) {
-          console.log(`Error: ${backupDir} not a directory.`);
-          return;
-        }
+        _checkBackupDirIsDir(backupDir);
 
         let backupDirContents = await fs.promises.readdir(backupDir, { withFileTypes: true });
 
@@ -80,24 +113,56 @@ async function runIfMain() {
             `Directory ${backupDir} is not empty, proceed anyway?\n` +
             'WARNING: This will remove all files in the directory!'
           );
+
           let proceed = await getUserInput();
-          if (!proceed) return;
+          if (!proceed) {
+            console.log('Aborting.');
+            return;
+          }
 
-          for (let backupDirContent of backupDirContents)
-            await fs.promises.rm(path.join(backupDir, backupDirContent.name), { recursive: true });
+          console.log(`Deleting files in ${backupDir}.`);
+          await deleteBackupDir({ backupDir, performChecks: false, _backupDirContents: backupDirContents });
         }
 
-        await fs.promises.mkdir(path.join(backupDir, 'files'));
+        console.log(`Initializing new hash backup in ${backupDir}`);
+        await initBackupDir({ backupDir, performChecks: false });
         break;
       }
 
-      case 'delete':
+      case 'delete': {
+        let backupDir = commandArgs[0];
+
+        if (backupDir == null || backupDir == '') backupDir = '.';
+
+        _checkBackupDirIsDir(backupDir);
+
+        let backupDirContents = await fs.promises.readdir(backupDir, { withFileTypes: true });
+
+        if (backupDirContents.length == 0) {
+          console.log(`Directory ${backupDir} already empty.`);
+          return;
+        }
+
+        console.log('WARNING: This will remove all files in the directory! Proceed?');
+
+        let proceed = await getUserInput();
+        if (!proceed) {
+          console.log('Aborting.');
+          return;
+        }
+
+        console.log(`Deleting files in ${backupDir}.`);
+        await deleteBackupDir({ backupDir, performChecks: false, _backupDirContents: backupDirContents });
         break;
+      }
     }
   }
 }
 
 module.exports = exports = {
+  _checkBackupDirIsDir,
+  getUserInput, getAllFilesInDir,
+  initBackupDir, deleteBackupDir,
   runIfMain,
 };
 

package.json

@@ -1,6 +1,6 @@
 {
   "name": "hash-backup",
-  "version": "0.0.0a",
+  "version": "0.0.1a",
   "description": "A hash based incremental file backupper.",
   "main": "hash_backup.js",
   "scripts": {