Checking npm-Version on npm-install

See: balderdashy#1742

.npmrc

@@ -0,0 +1 @@
+unsafe-perm=true

lib/preinstall_npmcheck.js

@@ -0,0 +1,114 @@
+/* Npm Preinstall Script
+* This Script checks if the installed npm-Version matches the 'engine'-Item in package.json
+ */
+
+var child_process = require('child_process'),
+    required_npm_version = require('./../package.json').engines.npm;
+
+
+/*
+ * Execute 'npm -v' and give back result
+ * @param {callback} cb - callback-function(err,version)
+ */
+
+var getNpmVersion = function(cb) {
+
+    child_process.exec('npm -v', function (err, stdout) {
+
+        if(err){
+            return cb(err);
+        }
+
+        // remove whitespaces
+        stdout = stdout.replace(/\s+/g, '');
+
+        // Check if version-number given back
+        if(!/^[0-9]{1,}\.[0-9]{1,}\.[0-9]{1,}$/.test(stdout)){
+            return cb('Unexpected output');
+        }
+
+        return cb(null,stdout);
+    });
+};
+
+/*
+ * Check if version of first paramter >= version of 2nd parameter
+ * ATTENTION: Only support '>='
+ * @param {string} v - Version to check (e.g. '10.5.2')
+ * @param {string} v2 - Version to check against (e.g. '0.8.14')
+ * @retrun {boolean}
+ */
+var checkVersion = function(v,v2) {
+
+    // Delete all of strings that dont necessary and make arrays
+    v = v.replace(/(\s+)|([^(0-9\.)])/g,'').split('.');
+    v2 = v2.replace(/(\s+)|([^(0-9\.)])/g,'').split('.');
+
+    if(v.length != 3 || !v2.length){
+        return false;
+    }
+
+    // Full with 0 if necessary
+    if(v2.length < 3) {
+        if(v2.length == 2){
+            v2.push([0]);
+        }else{
+            v2.push([0,0]);
+        }
+
+    }
+
+    var found = undefined;
+    v.forEach(function(item,key) {
+        if(found === undefined){
+
+            if(item > v2[key]) {
+                found = true;
+            }else if(item < v2[key]) {
+                found = false;
+            }
+
+        }
+    });
+
+    return found;
+
+};
+
+
+getNpmVersion(function(err,version){
+
+    // If no npm found at 'engine'-Item in package.json
+    if(required_npm_version === undefined){
+        return process.exit(0);
+    }
+
+    if(err){
+        console.log('\033[31mSails.js Installation - Error');
+        console.log('--------------------------------------------------------\033[00m');
+        console.log('Unable to check your npm-version');
+        console.log('');
+        console.log('Please reinstall npm to use Sails.js');
+        console.log('\033[31m--------------------------------------------------------');
+        return process.exit(1);
+    }
+
+
+    // If installed Version to old
+    if(!checkVersion(version,required_npm_version)){
+        console.log('\033[31mSails.js Installation - Error');
+        console.log('--------------------------------------------------------\033[00m');
+        console.log('Your npm-Version is too old:');
+        console.log('Sails require npm ' +required_npm_version+ ' (you currently have '+ version +')');
+        console.log('');
+        console.log('Please update the installed npm (Node Package Manager)');
+        console.log(' to install Sails.');
+        console.log('\033[31m--------------------------------------------------------');
+        return process.exit(1);
+    }
+
+    console.log('Sails.js Installation: Checking npm-version successful');
+    return process.exit(0);
+
+});
+

package.json

@@ -22,7 +22,8 @@
   },
   "scripts": {
     "test": "mocha -b",
-    "prepublish": "npm prune"
+    "prepublish": "npm prune",
+    "preinstall" : "node ./lib/preinstall_npmcheck.js"
   },
   "directories": {
     "lib": "lib"
@@ -105,6 +106,7 @@
     "url": "http://github.com/balderdashy/sails/issues"
   },
   "engines": {
-    "node": ">= 0.10.0"
+    "node": ">= 0.10.0",
+    "npm": ">= 1.4.0"
   }
 }