Merge pull request #5 from bolorundurowb/develop

release: v2.0.0
bolorundurowb · Mar 9, 2018 · 2a6542a · 2a6542a
2 parents ae510bf + fe8fd4d
commit 2a6542a
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Showing 4 changed files with 54 additions and 26 deletions.
diff --git a/README.md b/README.md
@@ -4,7 +4,7 @@
 
 ## About ShortId
 
-A csharp library to generate completely random short id's. they can be used as primary keys or unique identifiers. This library is different in that you can specify the length of the id's generated. I have tested the application generating 200000 ids without duplicates.
+A csharp library to generate completely random short id's. they can be used as primary keys or unique identifiers. This library is different in that you can specify the length of the id's generated. I have tested the application generating 180000 id's without duplicates.
 
 ## How to use
 
@@ -57,7 +57,7 @@ string id = ShortId.Generate(true, false, 12);
 // id = VvoCDPazES_w
 ```
 
-**NOTE: when specifying the desired length, shorter lengths increase the possibility thata duplicate id would be generated**
+**NOTE: v2.0.0 introduced a change that prevents lengths of less than 7**
 
 
 ## Customize ShortId
@@ -71,7 +71,7 @@ string characters = //whatever you want;
 ShortId.SetCharacters(characters);
 ```
 
-**NOTE: the new character set must number `null`, an empty string or whitespace. Also, all whitespace characters would be removed, finally the character set cannot be less than 20 characters.**
+**NOTE: the new character set must not be `null`, an empty string or whitespace. Also, all whitespace characters would be removed, finally the character set cannot be less than 20 characters.**
 
 `ShortId` also allows the seed for the random number generator to be set.
 

diff --git a/shortid.Test/ShortId.Tests.cs b/shortid.Test/ShortId.Tests.cs
@@ -8,7 +8,7 @@ namespace shortid.Test
     public class ShortIdTests
     {
         [Fact]
-        public void GenerateIsStable()
+        public void generatedWithoutExceptions()
         {
             string id = string.Empty;
             Action action = () =>
@@ -65,7 +65,7 @@ public void SetSeedThrowsWhenCharacterSetIsLessThan20Characters()
                 ShortId.SetCharacters(seed);
             };
             action.ShouldThrow<InvalidOperationException>()
-                .WithMessage("The replacement characters must be at least 20 letters in length and without spaces.");
+                .WithMessage("The replacement characters must be at least 20 letters in length and without whitespace.");
         }
 
         [Fact]
@@ -79,13 +79,14 @@ public void ResetIsStable()
         }
 
         [Fact]
-        public void SetSeedIsStable()
+        public void DoesNotAllowLengthsLessThan7()
         {
             Action action = () =>
             {
-                ShortId.Generate(0);
+                ShortId.Generate(6);
             };
-            action.ShouldNotThrow();
+            action.ShouldThrowExactly<ArgumentException>()
+                .WithMessage("The specified length of 6 is less than the lower limit of 7.");
         }
     }
 }
diff --git a/shortid/ShortId.cs b/shortid/ShortId.cs
@@ -3,17 +3,21 @@
 
 namespace shortid
 {
-    public class ShortId
+    public static class ShortId
     {
+        // app variables
         private static Random _random = new Random();
         private const string Bigs = "ABCDEFGHIJKLMNOPQRSTUVWXY";
         private const string Smalls = "abcdefghjlkmnopqrstuvwxyz";
         private const string Numbers = "0123456789";
         private const string Specials = "-_";
         private static string _pool = $"{Smalls}{Bigs}";
+
+        // thread management variables
+        private static readonly object threadLock = new object();
 
         /// <summary>
-        /// Generates a random string of varying length
+        /// Generates a random string of varying length with special characters and without numbers 
         /// </summary>
         /// <param name="useNumbers">Whether or not to include numbers</param>
         /// <param name="useSpecial">Whether or not special characters are included</param>
@@ -33,7 +37,21 @@ public static string Generate(bool useNumbers = false, bool useSpecial = true)
         /// <returns>A random string</returns>
         public static string Generate(bool useNumbers, bool useSpecial, int length)
         {
-            StringBuilder poolBuilder = new StringBuilder(_pool);
+            if (length < 7)
+            {
+                throw new ArgumentException($"The specified length of {length} is less than the lower limit of 7.");
+            }
+
+            string __pool;
+            Random rand;
+
+            lock (threadLock)
+            {
+                __pool = _pool;
+                rand = _random;
+            }
+
+            StringBuilder poolBuilder = new StringBuilder(__pool);
             if (useNumbers)
             {
                 poolBuilder.Append(Numbers);
@@ -48,14 +66,14 @@ public static string Generate(bool useNumbers, bool useSpecial, int length)
             char[] output = new char[length];
             for (int i = 0; i < length; i++)
             {
-                int charIndex = _random.Next(0, pool.Length);
+                int charIndex = rand.Next(0, pool.Length);
                 output[i] =  pool[charIndex];
             }
             return new string(output);
         }
 
         /// <summary>
-        /// Generates a random string of a specified length
+        /// Generates a random string of a specified length with special characetrs and without numbers
         /// </summary>
         /// <param name="length">The length of the generated string</param>
         /// <returns>A random string</returns>
@@ -76,18 +94,21 @@ public static void SetCharacters(string characters)
                 throw new ArgumentException("The replacement characters must not be null or empty.");
             }
 
-            characters = characters
-                .Replace(" ", "")
-                .Replace("\t", "")
-                .Replace("\n", "")
-                .Replace("\r", "");
+            var stringBuilder = new StringBuilder();
+            foreach (var character in characters)
+            {
+                if (!char.IsWhiteSpace(character)) {
+                    stringBuilder.Append(character);
+                }
+            }
 
-            if (characters.Length < 20)
+            if (stringBuilder.Length < 20)
             {
                 throw new InvalidOperationException(
-                    "The replacement characters must be at least 20 letters in length and without spaces.");
+                    "The replacement characters must be at least 20 letters in length and without whitespace.");
             }
-            _pool = characters;
+
+            _pool = stringBuilder.ToString();
         }
 
         /// <summary>
@@ -96,16 +117,22 @@ public static void SetCharacters(string characters)
         /// <param name="seed">The seed for the random number generator</param>
         public static void SetSeed(int seed)
         {
-            _random = new Random(seed);
+            lock (threadLock)
+            {
+                _random = new Random(seed);
+            }
         }
 
         /// <summary>
         /// Resets the random number generator and character set
         /// </summary>
         public static void Reset()
         {
-            _random = new Random();
-            _pool = $"{Smalls}{Bigs}";
+            lock (threadLock)
+            {
+                _random = new Random();
+                _pool = $"{Smalls}{Bigs}";
+            }
         }
     }
 }
diff --git a/shortid/shortid.csproj b/shortid/shortid.csproj
@@ -1,14 +1,14 @@
 <Project Sdk="Microsoft.NET.Sdk">
   <PropertyGroup>
     <TargetFrameworks>netstandard1.3;net45;net40</TargetFrameworks>
-    <Version>1.0.4</Version>
+    <Version>2.0.0</Version>
     <Copyright>Copyright 2017</Copyright>
     <PackageLicenseUrl>https://github.com/bolorundurowb/shortid/blob/master/LICENSE</PackageLicenseUrl>
     <PackageProjectUrl>https://github.com/bolorundurowb/shortid/</PackageProjectUrl>
     <PackageIconUrl>https://members.orcid.org/sites/default/files/vector_iD_icon.svg</PackageIconUrl>
     <RepositoryUrl>https://github.com/bolorundurowb/shortid/</RepositoryUrl>
     <PackageTags>shortid short id databse key primarykey mongodb sql</PackageTags>
-    <PackageReleaseNotes>Add memory optimizing changes</PackageReleaseNotes>
+    <PackageReleaseNotes>add thread safety and minimum length</PackageReleaseNotes>
     <Authors>Bolorunduro Winner-Timothy</Authors>
     <Description>A library that generates random Id's from 7 to 14 characters. Id's generated can be used as primary keys for databases or unique identifiers</Description>
     <PackageRequireLicenseAcceptance>true</PackageRequireLicenseAcceptance>