randomstring - npm Package Compare versions

Comparing version 1.1.5 to 1.2.0

CHANGELOG.md

@@ -0,1 +1,7 @@
+1.2.0 / May 10, 2021
+==================
+  * Use randombytes instead of node.crypto to prevent biased output
+  * Add support for async generation
+  * Support for binary and octal charsets
+
 1.1.5 / May 18, 2016
@@ -2,0 +8,0 @@ ==================

lib/charset.js

@@ -9,8 +9,10 @@ var arrayUniq = require('array-uniq');
   var chars;
-  
-  var numbers    = '0123456789';
-  var charsLower = 'abcdefghijklmnopqrstuvwxyz';
-  var charsUpper = charsLower.toUpperCase();
-  var hexChars   = 'abcdef';
-  
+
+  var numbers     = '0123456789';
+  var charsLower  = 'abcdefghijklmnopqrstuvwxyz';
+  var charsUpper  = charsLower.toUpperCase();
+  var hexChars    = 'abcdef';
+  var binaryChars = '01';
+  var octalChars  = '01234567';
+
   if (type === 'alphanumeric') {
@@ -28,6 +30,12 @@ chars = numbers + charsLower + charsUpper;
   }
+  else if (type === 'binary') {
+    chars = binaryChars;
+  }
+  else if (type === 'octal') {
+    chars = octalChars;
+  }
   else {
     chars = type;
   }
-  
+
   this.chars = chars;
@@ -56,2 +64,2 @@ }
 
-module.exports = exports = Charset;
+module.exports = exports = Charset;

lib/randomstring.js

 "use strict";
 
-var crypto  = require('crypto');
+var randomBytes = require('randombytes');
 var Charset = require('./charset.js');
@@ -9,3 +9,3 @@
     try {
-      return crypto.randomBytes(length);
+      return randomBytes(length);
     } catch(e) {
@@ -17,12 +17,37 @@ continue;
 
-exports.generate = function(options) {
-  
+function processString(buf, initialString, chars, reqLen, maxByte) {
+  var string = initialString;
+  for (var i = 0; i < buf.length && string.length < reqLen; i++) {
+    var randomByte = buf.readUInt8(i);
+    if (randomByte < maxByte) {
+      string += chars.charAt(randomByte % chars.length);
+    }
+  }
+  return string;
+}
+
+function getAsyncString(string, chars, length, maxByte, cb) {
+  crypto.randomBytes(length, function(err, buf) {
+    if (err) {
+      // Since it is waiting for entropy, errors are legit and we shouldn't just keep retrying
+      cb(err);
+    }
+    var generatedString = processString(buf, string, chars, length, maxByte);
+    if (generatedString.length < length) {
+      getAsyncString(generatedString, chars, length, maxByte, cb);
+    } else {
+      cb(null, generatedString);
+    }
+  })
+}
+
+exports.generate = function(options, cb) {
   var charset = new Charset();
-  
+
   var length, chars, capitalization, string = '';
-  
+
   // Handle options
   if (typeof options === 'object') {
     length = options.length || 32;
-    
+
     if (options.charset) {
@@ -34,11 +59,11 @@ charset.setType(options.charset);
     }
-    
+
     if (options.capitalization) {
       charset.setcapitalization(options.capitalization);
     }
-    
+
     if (options.readable) {
       charset.removeUnreadable();
     }
-    
+
     charset.removeDuplicates();
@@ -54,18 +79,18 @@ }
   }
-  
+
   // Generate the string
   var charsLen = charset.chars.length;
   var maxByte = 256 - (256 % charsLen);
-  while (length > 0) {
-    var buf = safeRandomBytes(Math.ceil(length * 256 / maxByte));
-    for (var i = 0; i < buf.length && length > 0; i++) {
-      var randomByte = buf.readUInt8(i);
-      if (randomByte < maxByte) {
-        string += charset.chars.charAt(randomByte % charsLen);
-        length--;
-      }
+
+  if (!cb) {
+    while (string.length < length) {
+      var buf = safeRandomBytes(Math.ceil(length * 256 / maxByte));
+      string = processString(buf, string, charset.chars, length, maxByte);
     }
+
+    return string;
   }
 
-  return string;
+  getAsyncString(string, charset.chars, length, maxByte, cb);
+
 };

package.json

 {
   "name": "randomstring",
-  "version": "1.1.5",
+  "version": "1.2.0",
   "author": "Elias Klughammer <[e-mail]> (http://www.klughammer.com)",
@@ -16,3 +16,4 @@ "description": "A module for generating random strings",
   "dependencies": {
-    "array-uniq": "1.0.2"  
+    "array-uniq": "1.0.2",
+    "randombytes": "2.0.3"
   },
@@ -19,0 +20,0 @@ "devDependencies": {

README.md

@@ -36,2 +36,8 @@ # node-randomstring
 // >> "accbaabbbbcccbccccaacacbbcbbcbbc"
+
+randomstring.generate({
+  charset: 'abc'
+}, cb);
+// >> "cb(generatedString) {}"
+
 ```
@@ -43,14 +49,18 @@
 
-- `generate(options)`
-  - `length` - the length of the random string. (default: 32) [OPTIONAL]
-  - `readable` - exclude poorly readable chars: 0OIl. (default: false) [OPTIONAL]
-  - `charset` - define the character set for the string. (default: 'alphanumeric') [OPTIONAL]
-    - `alphanumeric` - [0-9 a-z A-Z]
-    - `alphabetic` - [a-z A-Z]
-    - `numeric` - [0-9]
-    - `hex` - [0-9 a-f]
-    - `custom` - any given characters
-  - `capitalization` - define whether the output should be lowercase / uppercase only. (default: null) [OPTIONAL]
-    - `lowercase`
-    - `uppercase`
+- `generate(options, cb)`
+  - `options`
+    - `length` - the length of the random string. (default: 32) [OPTIONAL]
+    - `readable` - exclude poorly readable chars: 0OIl. (default: false) [OPTIONAL]
+    - `charset` - define the character set for the string. (default: 'alphanumeric') [OPTIONAL]
+      - `alphanumeric` - [0-9 a-z A-Z]
+      - `alphabetic` - [a-z A-Z]
+      - `numeric` - [0-9]
+      - `hex` - [0-9 a-f]
+      - `binary` - [01]
+      - `octal` - [0-7]
+      - `custom` - any given characters
+    - `capitalization` - define whether the output should be lowercase / uppercase only. (default: null) [OPTIONAL]
+      - `lowercase`
+      - `uppercase`
+  - `cb` - Optional.  If provided uses async version of `crypto.randombytes`
 
@@ -66,3 +76,3 @@ ## Command Line Usage
     > CpMg433
-    
+
     $ randomstring length=24 charset=github readable
@@ -69,0 +79,0 @@ > hthbtgiguihgbuttuutubugg

test/index.js

@@ -14,2 +14,9 @@ "use strict";
 
+  it("returns a string async", function(done) {
+    random(undefined, function(err, string) {
+      assert.equal(typeof(string), "string");
+      done();
+    });
+  });
+
   it("defaults to 32 characters in length", function() {
@@ -22,19 +29,31 @@ assert.equal(random().length, 32);
   });
-  
+
   it("accepts length as an option param", function() {
     assert.equal(random({ length: 7 }).length, 7);
   });
-  
-  it("accepts 'numeric' as charset option", function() {
-    var testData = random({ length: testLength, charset: 'numeric' });
-    var search = testData.search(/\D/ig);
-    assert.equal(search, -1);
+
+  it("accepts length as an option param async", function(done) {
+    random(({ length: 7 }), function(err, string) {
+      assert.equal(string.length, 7);
+      done();
+    });
   });
+
+  it("accepts 'numeric' as charset option async", function(done) {
+    random({ length: testLength, charset: 'numeric' }, function(err, testData) {
+      assert.equal(testData.length, testLength);
+      var search = testData.search(/\D/ig);
+      assert.equal(search, -1);
+      done();
+    });
+  });
   
-  it("accepts 'alphabetic' as charset option", function() {
-    var testData = random({ length: testLength, charset: 'alphabetic' });
-    var search = testData.search(/\d/ig);
-    assert.equal(search, -1);
+  it("accepts 'alphabetic' as charset option async", function(done) {
+    var testData = random({ length: testLength, charset: 'alphabetic' }, function(err, testData) {
+      var search = testData.search(/\d/ig);
+      assert.equal(search, -1);
+      done();
+    });
   });
-  
+
   it("accepts 'hex' as charset option", function() {
@@ -46,2 +65,14 @@ var testData = random({ length: testLength, charset: 'hex' });
   
+  it("accepts 'binary' as charset option", function() {
+    var testData = random({ length: testLength, charset: 'binary' });
+    var search = testData.search(/[^01]/ig);
+    assert.equal(search, -1);
+  });
+
+  it("accepts 'octal' as charset option", function() {
+    var testData = random({ length: testLength, charset: 'octal' });
+    var search = testData.search(/[^0-7]/ig);
+    assert.equal(search, -1);
+  });
+
   it("accepts custom charset", function() {
@@ -53,2 +84,11 @@ var charset = "abc";
   });
+
+  it("accepts custom charset async", function(done) {
+    var charset = "abc";
+    random({ length: testLength, charset: charset }, function(err, testData) {
+      var search = testData.search(/[^abc]/ig);
+      assert.equal(search, -1);
+      done();
+    });
+  });
   
@@ -60,3 +100,3 @@ it("accepts readable option", function() {
   });
-  
+
   it("accepts 'uppercase' as capitalization option", function() {
@@ -67,3 +107,3 @@ var testData = random({ length: testLength, capitalization: 'uppercase'});
   });
-  
+
   it("accepts 'lowercase' as capitalization option", function() {
@@ -85,2 +125,19 @@ var testData = random({ length: testLength, capitalization: 'lowercase'});
 
+  it("returns unique strings async", function(done) {
+    var results = [];
+    function doTest() {
+      random(undefined, function(err, string) {
+        assert.equal(results.indexOf(string), -1);
+        results.push(string);
+        if (results.length >= 1000) {
+          done();
+        } else {
+          doTest();
+        }
+      });
+    }
+
+    doTest();
+  });
+
   it("returns unbiased strings", function() {
@@ -107,2 +164,25 @@ var charset = 'abcdefghijklmnopqrstuvwxyz';
 
+  it("returns unbiased strings async", function(done) {
+    var charset = 'abcdefghijklmnopqrstuvwxyz';
+    var slen = 100000;
+    random({ charset: charset, length: slen }, function(err, s) {
+      var counts = {};
+      for (var i = 0; i < s.length; i++) {
+        var c = s.charAt(i);
+        if (typeof counts[c] === "undefined") {
+          counts[c] = 0;
+        } else {
+          counts[c]++;
+        }
+      }
+      var avg = slen / charset.length;
+      Object.keys(counts).sort().forEach(function(k) {
+        var diff = counts[k] / avg;
+        assert(diff > 0.95 && diff < 1.05,
+               "bias on `" + k + "': expected average is " + avg + ", got " + counts[k]);
+      });
+      done();
+    });
+
+  });
 });

No alert changes

Improved metrics

Total package byte prevSize

14870

increased by32.28%

Lines of code

285

increased by55.74%

Number of lines in readme file

88

increased by12.82%

Worsened metrics

Dependency count

2

increased by100%

Number of package files

12

decreased by-7.69%

Dependency changes

• + Addedrandombytes@2.0.3

• + Addedrandombytes@2.0.3(transitive)