Adding an option to limit the number of files to be deleted at a single operation

README.md

@@ -59,10 +59,10 @@ var result = findRemoveSync('/temp', {extensions: ['.bak'], ignore: 'haumiblau.b
 var result = findRemoveSync('/dist', {dir: 'CVS'})
 ```
 
-### 6. delete all jpg files older than one hour
+### 6. delete all jpg files older than one hour with limit of 100 files deletion per operation
 
 ```javascript
-var result = findRemoveSync('/tmp', {age: {seconds: 3600}, extensions: '.jpg'})
+var result = findRemoveSync('/tmp', {age: {seconds: 3600}, extensions: '.jpg', limit: 100})
 ```
 
 ### 7. apply filter options only for two levels inside the /temp directory for all tmp files
@@ -98,6 +98,7 @@ __arguments__
     * `extensions` - this too, can be a string or an array of file extenstions you want to delete within `dir`.
     * `ignore` - useful to exclude some files. again, can be a string or an array of file names you do NOT want to delete within `dir`
     * `age.seconds` - can be any float number. findRemoveSync then compares it with the file stats and deletes those with creation times older than `age.seconds`
+    * `limit` - can be any integer number. Will limit the number of <b>files</b> to be deleted at single operation to be `limit`
     * `maxLevel` - advanced: limits filtering to a certain level. useful for performance. recommended for crawling huge directory trees.
     * `test` - advanced: set to true for a test run, meaning it does not delete anything but returns a JSON of files/directories it would have deleted. useful for testing.
 
@@ -107,7 +108,7 @@ the unit tests are good examples on how to use the above arguments.
 
 __returns__
 
-JSON of files/directories that were deleted.
+JSON of files/directories that were deleted. For limit option - will only return number of files deleted.
 
 ## todo
 

find-remove.js

@@ -15,6 +15,26 @@ function isOlder(path, ageSeconds) {
     return now > expirationTime
 }
 
+function hasLimit(options) {
+    return options && options.hasOwnProperty('limit')
+}
+
+function getLimit(options) {
+    return hasLimit(options) ? options.limit : -1
+}
+
+function hasTotalRemoved(options) {
+    return options && options.hasOwnProperty('totalRemoved')
+}
+
+function getTotalRemoved(options) {
+    return hasTotalRemoved(options) ? options.totalRemoved : -2
+}
+
+function isOverTheLimit(options) {
+    return getTotalRemoved(options) >= getLimit(options)
+}
+
 function hasMaxLevel(options) {
     return options && options.hasOwnProperty('maxLevel')
 }
@@ -42,6 +62,10 @@ function doDeleteDirectory(currentDir, options, currentLevel) {
             doDelete = true
         }
 
+        if (doDelete && hasLimit(options)) {
+            doDelete = !isOverTheLimit(options)
+        }
+
         if (doDelete && hasMaxLevel(options) && currentLevel > 0) {
             doDelete = currentLevel <= getMaxLevel(options)
         }
@@ -88,6 +112,10 @@ function doDeleteFile(currentFile, options) {
         }
     }
 
+    if (doDelete && hasLimit(options)) {
+        doDelete = !isOverTheLimit(options)
+    }
+
     if (doDelete && ignore) {
         if (util.isArray(ignore))
             doDelete = !(ignore.indexOf(basename) !== -1)
@@ -127,11 +155,15 @@ var findRemoveSync = module.exports = function(currentDir, options, currentLevel
 
     var removed = {}
 
-    if (fs.existsSync(currentDir)) {
+    if (!isOverTheLimit(options) && fs.existsSync(currentDir)) {
 
         var maxLevel = getMaxLevel(options),
             deleteDirectory = false
 
+        if (hasLimit(options)) {
+            options.totalRemoved = hasTotalRemoved(options) ? getTotalRemoved(options) : 0
+        }
+
         if (currentLevel === undefined)
             currentLevel = 0
         else
@@ -160,13 +192,19 @@ var findRemoveSync = module.exports = function(currentDir, options, currentLevel
 
                     // merge results
                     removed = merge(removed, result)
+                    if (hasTotalRemoved(options))
+                        options.totalRemoved += Object.keys(result).length
+
                 } else {
 
                     if (doDeleteFile(currentFile, options)) {
                         if (!testRun)
                             fs.unlinkSync(currentFile)
 
                         removed[currentFile] = true
+                        if (hasTotalRemoved(options))
+                            options.totalRemoved ++
+
                     }
                 }
             })
@@ -177,7 +215,10 @@ var findRemoveSync = module.exports = function(currentDir, options, currentLevel
                 if (!testRun)
                     rimraf.sync(currentDir)
 
-                removed[currentDir] = true
+                if (!hasTotalRemoved(options))
+                    // for limit of files - we do not want to count the directories
+                    removed[currentDir] = true
+
             } catch (err) {
                 throw err
             }

tests/basics.js

@@ -703,5 +703,32 @@ module.exports = testCase({
 
             t.done()
         }
+    }),
+
+    'TC 5: limit checks': testCase({
+
+        setUp: function(cb) {
+            createFakeDirectoryTree(cb)
+        },
+        tearDown: function(cb) {
+            destroyFakeDirectoryTree(cb)
+        },
+
+        'findRemoveSync(files older than .0005 sec with limit of 2)': function(t) {
+            var result = findRemoveSync(rootDirectory, {files: "*.*", age: {seconds: 0.0005}, limit: 2})
+
+            t.strictEqual(Object.keys(result).length, 2, 'findRemoveSync(files older than .0005 sec) returned 2 entries (out of 11).')
+
+            t.done()
+        },
+
+        'findRemoveSync(files and dirs older than .0005 sec with limit of 5)': function(t) {
+            var result = findRemoveSync(rootDirectory, {files: "*.*", dir: "*", age: {seconds: 0.0005}, limit: 5})
+
+            t.strictEqual(Object.keys(result).length, 5, 'findRemoveSync(files older than .0005 sec) returned 5 entries (out of 19).')
+
+            t.done()
+        }
+
     })
 })