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README.md

@@ -1 +1,25 @@
-# sudo
+# Sudo
+
+Run a command using sudo, prompting the user with an OS dialog if necessary.
+
+Currently supports native OS dialog on Mac OS X (patches welcome for Linux).
+
+Sudo has no external dependencies and does not contain any native bindings.
+
+## Usage
+Note that your command should not contain the sudo prefix.
+```
+// To run a command using sudo:
+var sudo = require('sudo-prompt');
+sudo.exec('echo hello', function(error) {});
+
+// To update the sudo timestamp for the current user:
+sudo.touch(function(error) {});
+
+// To use something other than process.title as the app name:
+// Must be alphanumeric (may contain spaces).
+sudo.setName('Your app name')
+```
+
+## Concurrency
+You can call Sudo.exec and Sudo.touch concurrently, Sudo will batch up permission requests into a single prompt.

index.js

@@ -0,0 +1,124 @@
+var Node = {
+  child: require('child_process'),
+  fs: require('fs'),
+  os: require('os'),
+  path: require('path'),
+  process: process
+};
+
+function escapeDoubleQuotes(string) {
+  return string.replace(/"/g, '\\"');
+}
+
+function validName(string) {
+  return /^[a-z0-9 ]+$/i.test(string) && string.trim().length > 0;
+}
+
+var Sudo = function(command, end) {
+  if (Node.process.platform === 'darwin') return Sudo.Mac(command, end);
+  end('Platform not yet supported.');
+  // TO DO: Add support for linux.
+};
+
+Sudo.name = undefined;
+
+Sudo.Mac = function(command, end, count) {
+  if (count === undefined) count = 0;
+  if (count >= 2) return end(new Error('Permission denied after several password prompts.'));
+  if (/^sudo/i.test(command)) return end(new Error('Command should not contain "sudo".'));
+  // Run sudo in non-interactive mode (-n).
+  Node.child.exec('sudo -n ' + command,
+    function(error, stdout, stderr) {
+      if (error) return end(error);
+      if (stderr !== 'sudo: a password is required\n') {
+        if (/^sudo:/i.test(stderr)) return end(stderr);
+        end(error, stdout, stderr);
+      } else {
+        Sudo.Mac.prompt(
+          function(error) {
+            if (error) return end(error);
+            Sudo.Mac(command, end, ++count); // Cannot use ++ suffix here.
+          }
+        );
+      }
+    }
+  );
+};
+
+Sudo.Mac.prompt = function(end) {
+  var self = this;
+  var title = Sudo.name || Node.process.title;
+  if (!validName(title)) return end(new Error('Please use sudo.setName(string) to set your app name (process.title contains invalid characters).'));
+  var temp = Node.os.tmpdir();
+  if (!temp) return end(new Error('Requires os.tmpdir() to be defined.'));
+  if (!Node.process.env.USER) return end(new Error('Requires env[\'USER\'] to be defined.'));
+  if (self.prompting) {
+    // Already waiting for user to enter password...
+    // We expect that Sudo.exec may be called multiple times.
+    // If a prompt is already pending, then we wait for the result of the prompt
+    // and do not trigger another permission request dialog.
+    self.prompting.push(end);
+  } else {
+    // Prompting user for password...
+    self.prompting = [end];
+    var finish = function(error) {
+      var callbacks = self.prompting;
+      self.prompting = false;
+      for (var index = 0, length = callbacks.length; index < length; index++) {
+        callbacks[index](error);
+      }
+    };
+    // We copy osascript to a new tmp location using the title of this process as the basename.
+    // We can then use this new binary to change the sudo timestamp, and OS X will use
+    // the title of this process when asking the user for permission.
+    Node.child.exec('which osascript',
+      function(error, stdout, stderr) {
+        if (error) return finish(error);
+        var source = stdout.trim();
+        var target = Node.path.join(temp, title);
+        Node.fs.readFile(source,
+          function(error, buffer) {
+            if (error) return finish(error);
+            Node.fs.writeFile(target, buffer,
+              function(error) {
+                if (error) return finish(error);
+                Node.fs.chmod(target, 0755,
+                  function(error) {
+                    if (error) return finish(error);
+                    // Set the sudo timestamp for our user:
+                    var command = '"' + escapeDoubleQuotes(target) + '" -e \'do shell script "mkdir -p /var/db/sudo/$USER; touch /var/db/sudo/$USER" with administrator privileges\'';
+                    Node.child.exec(command,
+                      function(error, stdout, stderr) {
+                        if (/user canceled/i.test(error)) error = new Error('User did not grant permission.');
+                        if (error) return finish(error);
+                        Node.fs.unlink(target, finish);
+                      }
+                    );
+                  }
+                );
+              }
+            );
+          }
+        );
+      }
+    );
+  }
+};
+
+Sudo.Mac.prompting = false;
+
+exports.exec = Sudo;
+
+exports.touch = function(end) {
+  Sudo('echo noop',
+    function(error) {
+      if (error) return end(error);
+      end();
+    }
+  );
+};
+
+exports.setName = function(string) {
+  if (!validName(string)) throw new Error('Name must be alphanumeric only (spaces are allowed).');
+  Sudo.name = string;
+};

package.json

@@ -0,0 +1,24 @@
+{
+  "name": "sudo-prompt",
+  "version": "1.0.0",
+  "description": "Run a command using sudo, prompting the user with an OS dialog if necessary",
+  "main": "index.js",
+  "repository": {
+    "type": "git",
+    "url": "git+https://github.com/jorangreef/sudo.git"
+  },
+  "keywords": [
+    "sudo",
+    "os",
+    "dialog",
+    "prompt",
+    "command",
+    "exec"
+  ],
+  "author": "Joran Dirk Greef",
+  "license": "MIT",
+  "bugs": {
+    "url": "https://github.com/jorangreef/sudo/issues"
+  },
+  "homepage": "https://github.com/jorangreef/sudo#readme"
+}