Add support for auth in URL

src/NATS.Client.Core/Internal/NatsUri.cs

@@ -4,6 +4,8 @@ internal sealed class NatsUri : IEquatable<NatsUri>
 {
     public const string DefaultScheme = "nats";
 
+    private readonly string _redacted;
+
     public NatsUri(string urlString, bool isSeed, string defaultScheme = DefaultScheme)
     {
         IsSeed = isSeed;
@@ -38,6 +40,21 @@ public NatsUri(string urlString, bool isSeed, string defaultScheme = DefaultSche
         }
 
         Uri = uriBuilder.Uri;
+
+        // Redact user/password or token from the URI string for logging
+        if (uriBuilder.UserName is { Length: > 0 })
+        {
+            if (uriBuilder.Password is { Length: > 0 })
+            {
+                uriBuilder.Password = "***";
+            }
+            else
+            {
+                uriBuilder.UserName = "***";
+            }
+        }
+
+        _redacted = IsWebSocket && Uri.AbsolutePath != "/" ? uriBuilder.Uri.ToString() : uriBuilder.Uri.ToString().Trim('/');
     }
 
     public Uri Uri { get; }
@@ -63,10 +80,7 @@ public NatsUri CloneWith(string host, int? port = default)
         return new NatsUri(newUri, IsSeed);
     }
 
-    public override string ToString()
-    {
-        return IsWebSocket && Uri.AbsolutePath != "/" ? Uri.ToString() : Uri.ToString().Trim('/');
-    }
+    public override string ToString() => _redacted;
 
     public override int GetHashCode() => Uri.GetHashCode();
 

src/NATS.Client.Core/NatsConnection.cs

@@ -1,6 +1,5 @@
 using System.Buffers;
 using System.Diagnostics;
-using System.Runtime.CompilerServices;
 using System.Threading.Channels;
 using Microsoft.Extensions.Logging;
 using NATS.Client.Core.Commands;
@@ -76,7 +75,7 @@ public NatsConnection()
     public NatsConnection(NatsOpts opts)
     {
         _logger = opts.LoggerFactory.CreateLogger<NatsConnection>();
-        Opts = opts;
+        Opts = opts.ReadUserInfoFromConnectionString();
         ConnectionState = NatsConnectionState.Closed;
         _waitForOpenConnection = new TaskCompletionSource(TaskCreationOptions.RunContinuationsAsynchronously);
         _disposedCancellationTokenSource = new CancellationTokenSource();

src/NATS.Client.Core/NatsOpts.cs

@@ -14,6 +14,28 @@ public sealed record NatsOpts
 {
     public static readonly NatsOpts Default = new();
 
+    /// <summary>
+    /// NATS server URL to connect to. (default: nats://localhost:4222)
+    /// </summary>
+    /// <remarks>
+    /// <para>
+    /// You can set more than one server as seed servers in a comma-separated list.
+    /// The client will randomly select a server from the list to connect to unless
+    /// <see cref="NoRandomize"/> (which is <c>false</c> by default) is set to <c>true</c>.
+    /// </para>
+    /// <para>
+    /// User-password or token authentication can be set in the URL.
+    /// For example, <c>nats://derek:s3cr3t@localhost:4222</c> or <c>nats://token@localhost:4222</c>.
+    /// You can also set the username and password or token separately using <see cref="AuthOpts"/>;
+    /// however, if both are set, the <see cref="AuthOpts"/> will take precedence.
+    /// You should URL-encode the username and password or token if they contain special characters.
+    /// </para>
+    /// <para>
+    /// If multiple servers are specified and user-password or token authentication is used in the URL,
+    /// only the credentials in the first server URL will be used; credentials in the remaining server
+    /// URLs will be ignored.
+    /// </para>
+    /// </remarks>
     public string Url { get; init; } = "nats://localhost:4222";
 
     public string Name { get; init; } = "NATS .NET Client";
@@ -117,11 +139,50 @@ public sealed record NatsOpts
     /// </remarks>
     public BoundedChannelFullMode SubPendingChannelFullMode { get; init; } = BoundedChannelFullMode.DropNewest;
 
-    internal NatsUri[] GetSeedUris()
+    internal NatsUri[] GetSeedUris(bool suppressRandomization = false)
     {
         var urls = Url.Split(',');
-        return NoRandomize
+        return NoRandomize || suppressRandomization
             ? urls.Select(x => new NatsUri(x, true)).Distinct().ToArray()
             : urls.Select(x => new NatsUri(x, true)).OrderBy(_ => Guid.NewGuid()).Distinct().ToArray();
     }
+
+    internal NatsOpts ReadUserInfoFromConnectionString()
+    {
+        // Setting credentials in options takes precedence over URL credentials
+        if (AuthOpts.Username is { Length: > 0 } || AuthOpts.Password is { Length: > 0 } || AuthOpts.Token is { Length: > 0 })
+        {
+            return this;
+        }
+
+        var natsUri = GetSeedUris(suppressRandomization: true).First();
+        var uriBuilder = new UriBuilder(natsUri.Uri);
+
+        if (uriBuilder.UserName is not { Length: > 0 })
+        {
+            return this;
+        }
+
+        if (uriBuilder.Password is { Length: > 0 })
+        {
+            return this with
+            {
+                AuthOpts = AuthOpts with
+                {
+                    Username = Uri.UnescapeDataString(uriBuilder.UserName),
+                    Password = Uri.UnescapeDataString(uriBuilder.Password),
+                },
+            };
+        }
+        else
+        {
+            return this with
+            {
+                AuthOpts = AuthOpts with
+                {
+                    Token = Uri.UnescapeDataString(uriBuilder.UserName),
+                },
+            };
+        }
+    }
 }

src/NATS.Client.Simplified/NatsClient.cs

@@ -11,9 +11,25 @@ public class NatsClient : INatsClient
     /// <summary>
     /// Initializes a new instance of the <see cref="NatsClient"/> class.
     /// </summary>
-    /// <param name="url">NATS server URL</param>
-    /// <param name="name">Client name</param>
-    /// <param name="credsFile">Credentials filepath</param>
+    /// <param name="url">NATS server URL to connect to. (default: nats://localhost:4222)</param>
+    /// <param name="name">Client name. (default: NATS .NET Client)</param>
+    /// <param name="credsFile">Credentials filepath.</param>
+    /// <remarks>
+    /// <para>
+    /// You can set more than one server as seed servers in a comma-separated list in the <paramref name="url"/>.
+    /// The client will randomly select a server from the list to connect.
+    /// </para>
+    /// <para>
+    /// User-password or token authentication can be set in the <paramref name="url"/>.
+    /// For example, <c>nats://derek:s3cr3t@localhost:4222</c> or <c>nats://token@localhost:4222</c>.
+    /// You should URL-encode the username and password or token if they contain special characters.
+    /// </para>
+    /// <para>
+    /// If multiple servers are specified and user-password or token authentication is used in the <paramref name="url"/>,
+    /// only the credentials in the first server URL will be used; credentials in the remaining server
+    /// URLs will be ignored.
+    /// </para>
+    /// </remarks>
     public NatsClient(
         string url = "nats://localhost:4222",
         string name = "NATS .NET Client",

tests/NATS.Client.Core.Tests/ClusterTests.cs

@@ -2,23 +2,43 @@ namespace NATS.Client.Core.Tests;
 
 public class ClusterTests(ITestOutputHelper output)
 {
-    [Fact]
-    public async Task Seed_urls_on_retry()
+    [Theory]
+    [InlineData(false)]
+    [InlineData(true)]
+    public async Task Seed_urls_on_retry(bool userAuthInUrl)
     {
         await using var cluster1 = new NatsCluster(
             new NullOutputHelper(),
             TransportType.Tcp,
-            (i, b) => b.WithServerName($"c1n{i}"));
+            (i, b) =>
+            {
+                b.WithServerName($"c1n{i}");
+                if (userAuthInUrl)
+                {
+                    b.AddServerConfig("resources/configs/auth/password.conf");
+                    b.WithClientUrlAuthentication("a", "b");
+                }
+            },
+            userAuthInUrl);
 
         await using var cluster2 = new NatsCluster(
             new NullOutputHelper(),
             TransportType.Tcp,
-            (i, b) => b.WithServerName($"c2n{i}"));
+            (i, b) =>
+            {
+                b.WithServerName($"c2n{i}");
+                if (userAuthInUrl)
+                {
+                    b.AddServerConfig("resources/configs/auth/password.conf");
+                    b.WithClientUrlAuthentication("a", "b");
+                }
+            },
+            userAuthInUrl);
 
         // Use the first node from each cluster as the seed
         // so that we can confirm seeds are used on retry
-        var url1 = cluster1.Server1.ClientUrl;
-        var url2 = cluster2.Server1.ClientUrl;
+        var url1 = userAuthInUrl ? cluster1.Server1.ClientUrlWithAuth : cluster1.Server1.ClientUrl;
+        var url2 = userAuthInUrl ? cluster2.Server1.ClientUrlWithAuth : cluster2.Server1.ClientUrl;
 
         await using var nats = new NatsConnection(new NatsOpts
         {

tests/NATS.Client.Core.Tests/NatsConnectionTest.Auth.cs

@@ -12,6 +12,15 @@ public static IEnumerable<object[]> GetAuthConfigs()
                 NatsOpts.Default with { AuthOpts = NatsAuthOpts.Default with { Token = "s3cr3t", }, }),
         };
 
+        yield return new object[]
+        {
+            new Auth(
+                "TOKEN_IN_CONNECTIONSTRING",
+                "resources/configs/auth/token.conf",
+                NatsOpts.Default,
+                urlAuth: "s3cr3t"),
+        };
+
         yield return new object[]
         {
             new Auth(
@@ -23,6 +32,15 @@ NatsOpts.Default with
                 }),
         };
 
+        yield return new object[]
+        {
+            new Auth(
+                "USER-PASSWORD_IN_CONNECTIONSTRING",
+                "resources/configs/auth/password.conf",
+                NatsOpts.Default,
+                urlAuth: "a:b"),
+        };
+
         yield return new object[]
         {
             new Auth(
@@ -84,15 +102,22 @@ public async Task UserCredentialAuthTest(Auth auth)
         var name = auth.Name;
         var serverConfig = auth.ServerConfig;
         var clientOpts = auth.ClientOpts;
+        var useAuthInUrl = !string.IsNullOrEmpty(auth.UrlAuth);
 
         _output.WriteLine($"AUTH TEST {name}");
 
-        var serverOpts = new NatsServerOptsBuilder()
+        var serverOptsBuilder = new NatsServerOptsBuilder()
             .UseTransport(_transportType)
-            .AddServerConfig(serverConfig)
-            .Build();
+            .AddServerConfig(serverConfig);
+
+        if (useAuthInUrl)
+        {
+            serverOptsBuilder.WithClientUrlAuthentication(auth.UrlAuth!);
+        }
 
-        await using var server = NatsServer.Start(_output, serverOpts, clientOpts);
+        var serverOpts = serverOptsBuilder.Build();
+
+        await using var server = NatsServer.Start(_output, serverOpts, clientOpts, useAuthInUrl);
 
         var subject = Guid.NewGuid().ToString("N");
 
@@ -104,8 +129,8 @@ public async Task UserCredentialAuthTest(Auth auth)
             Assert.Contains("Authorization Violation", natsException.GetBaseException().Message);
         }
 
-        await using var subConnection = server.CreateClientConnection(clientOpts);
-        await using var pubConnection = server.CreateClientConnection(clientOpts);
+        await using var subConnection = server.CreateClientConnection(clientOpts, useAuthInUrl: useAuthInUrl);
+        await using var pubConnection = server.CreateClientConnection(clientOpts, useAuthInUrl: useAuthInUrl);
 
         var signalComplete1 = new WaitSignal();
         var signalComplete2 = new WaitSignal();
@@ -141,7 +166,7 @@ await Retry.Until(
         await disconnectSignal2;
 
         _output.WriteLine("START NEW SERVER");
-        await using var newServer = NatsServer.Start(_output, serverOpts, clientOpts);
+        await using var newServer = NatsServer.Start(_output, serverOpts, clientOpts, useAuthInUrl);
         await subConnection.ConnectAsync(); // wait open again
         await pubConnection.ConnectAsync(); // wait open again
 
@@ -162,11 +187,12 @@ await Retry.Until(
 
     public class Auth
     {
-        public Auth(string name, string serverConfig, NatsOpts clientOpts)
+        public Auth(string name, string serverConfig, NatsOpts clientOpts, string? urlAuth = null)
         {
             Name = name;
             ServerConfig = serverConfig;
             ClientOpts = clientOpts;
+            UrlAuth = urlAuth;
         }
 
         public string Name { get; }
@@ -175,6 +201,8 @@ public Auth(string name, string serverConfig, NatsOpts clientOpts)
 
         public NatsOpts ClientOpts { get; }
 
+        public string? UrlAuth { get; }
+
         public override string ToString() => Name;
     }
 }