Merge pull request baalexander#28 from darthneko/master

Accept lists of ports

example/portscan-list.js

@@ -0,0 +1,11 @@
+var http        = require('http')
+  , portscanner = require('../lib/portscanner.js')
+
+// Check if one of the ports in the list is available
+portscanner.findAPortNotInUse([4443, 4444, 4447], '127.0.0.1', function(error, port) {
+	if (!error) {
+		console.log('Available port: ' + port);
+	} else {
+		console.log('There was an error');
+	}
+});

lib/portscanner.js

@@ -23,6 +23,23 @@ portscanner.findAPortInUse = function(startPort, endPort, host, callback) {
   findAPortWithStatus('open', startPort, endPort, host, callback)
 }
 
+/**
+ * Finds the first port with a status of 'open', implying the port is in use and
+ * there is likely a service listening on it.
+ *
+ * @param {List} portList     - List of ports to check on.
+ * @param {String} host       - Where to scan. Defaults to '127.0.0.1'.
+ * @param {Function} callback - function (error, port) { ... }
+ *   - {Object|null} error    - Any errors that occurred while port scanning.
+ *   - {Number|Boolean} port  - The first open port found. Note, this is the
+ *                              first port that returns status as 'open', not
+ *                              necessarily the first open port checked. If no
+ *                              open port is found, the value is false.
+ */
+portscanner.findAPortInUse = function(portList, host, callback) {
+  findAPortWithStatus('open', portList, host, callback)
+}
+
 /**
  * Finds the first port with a status of 'closed', implying the port is not in
  * use.
@@ -42,6 +59,23 @@ portscanner.findAPortNotInUse = function(startPort, endPort, host, callback) {
   findAPortWithStatus('closed', startPort, endPort, host, callback)
 }
 
+/**
+ * Finds the first port with a status of 'closed', implying the port is not in
+ * use.
+ *
+ * @param {List} portList     - List of ports to check on.
+ * @param {String} host       - Where to scan. Defaults to '127.0.0.1'.
+ * @param {Function} callback - function (error, port) { ... }
+ *   - {Object|null} error    - Any errors that occurred while port scanning.
+ *   - {Number|Boolean} port  - The first closed port found. Note, this is the
+ *                              first port that returns status as 'closed', not
+ *                              necessarily the first closed port checked. If no
+ *                              closed port is found, the value is false.
+ */
+portscanner.findAPortNotInUse = function(portList, host, callback) {
+  findAPortWithStatus('closed', portList, host, callback)
+}
+
 /**
  * Checks the status of an individual port.
  *
@@ -108,7 +142,7 @@ portscanner.checkPortStatus = function(port, options, callback) {
 }
 
 function findAPortWithStatus(status, startPort, endPort, host, callback) {
-  endPort = endPort || 65535
+  var endPort = endPort || 65535
   var foundPort = false
   var numberOfPortsChecked = 0
   var port = startPort
@@ -149,3 +183,43 @@ function findAPortWithStatus(status, startPort, endPort, host, callback) {
   })
 }
 
+function findAPortWithStatus(status, portList, host, callback) {
+  var foundPort = false
+  var portIndex = 0
+  var port = portList[portIndex]
+
+  // Returns true if a port with matching status has been found or if checked
+  // the entire range of ports
+  var hasFoundPort = function() {
+    return foundPort || portIndex === portList.length
+  }
+
+  // Checks the status of the port
+  var checkNextPort = function(callback) {
+    portscanner.checkPortStatus(port, host, function(error, statusOfPort) {
+      if (statusOfPort === status) {
+        foundPort = true
+        callback(error)
+      }
+      else {
+        port = portList[++portIndex]
+        callback(null)
+      }
+    })
+  }
+
+  // Check the status of each port until one with a matching status has been
+  // found or the range of ports has been exhausted
+  async.until(hasFoundPort, checkNextPort, function(error) {
+    if (error) {
+      callback(error, port)
+    }
+    else if (foundPort) {
+      callback(null, port)
+    }
+    else {
+      callback(null, false)
+    }
+  })
+}
+