Add Condition.SortedSet[Not]ContainsStarting condition for transactions (#2638)

* New-SortedSetStartsWith-Condition

* fix formatting rules

* clean up and optimize

* tests for sorted-set-starts-with condition
IDE noise cleanup

* release notes / shipped

---------

Co-authored-by: Marc Gravell <marc.gravell@gmail.com>

Author: ArnoKoll

docs/ReleaseNotes.md

@@ -10,6 +10,7 @@ Current package versions:
 
 - Add `HGETDEL`, `HGETEX` and `HSETEX` support ([#2863 by atakavci](https://github.com/StackExchange/StackExchange.Redis/pull/2863))
 - Fix key-prefix omission in `SetIntersectionLength` and `SortedSet{Combine[WithScores]|IntersectionLength}` ([#2863 by mgravell](https://github.com/StackExchange/StackExchange.Redis/pull/2863))
+- Add `Condition.SortedSet[Not]ContainsStarting` condition for transactions ([#2638 by ArnoKoll](https://github.com/StackExchange/StackExchange.Redis/pull/2638))
 
 ## 2.8.58
 

src/StackExchange.Redis/Condition.cs

@@ -284,6 +284,20 @@ public static Condition StringNotEqual(RedisKey key, RedisValue value)
         /// <param name="member">The member the sorted set must not contain.</param>
         public static Condition SortedSetNotContains(RedisKey key, RedisValue member) => new ExistsCondition(key, RedisType.SortedSet, member, false);
 
+        /// <summary>
+        /// Enforces that the given sorted set contains a member that starts with the specified prefix.
+        /// </summary>
+        /// <param name="key">The key of the sorted set to check.</param>
+        /// <param name="prefix">The sorted set must contain at least one member that starts with the specified prefix.</param>
+        public static Condition SortedSetContainsStarting(RedisKey key, RedisValue prefix) => new StartsWithCondition(key, prefix, true);
+
+        /// <summary>
+        /// Enforces that the given sorted set does not contain a member that starts with the specified prefix.
+        /// </summary>
+        /// <param name="key">The key of the sorted set to check.</param>
+        /// <param name="prefix">The sorted set must not contain at a member that starts with the specified prefix.</param>
+        public static Condition SortedSetNotContainsStarting(RedisKey key, RedisValue prefix) => new StartsWithCondition(key, prefix, false);
+
         /// <summary>
         /// Enforces that the given sorted set member must have the specified score.
         /// </summary>
@@ -370,6 +384,9 @@ public static Message CreateMessage(Condition condition, int db, CommandFlags fl
             public static Message CreateMessage(Condition condition, int db, CommandFlags flags, RedisCommand command, in RedisKey key, in RedisValue value, in RedisValue value1) =>
                 new ConditionMessage(condition, db, flags, command, key, value, value1);
 
+            public static Message CreateMessage(Condition condition, int db, CommandFlags flags, RedisCommand command, in RedisKey key, in RedisValue value, in RedisValue value1, in RedisValue value2, in RedisValue value3, in RedisValue value4) =>
+                new ConditionMessage(condition, db, flags, command, key, value, value1, value2, value3, value4);
+
             [System.Diagnostics.CodeAnalysis.SuppressMessage("Style", "IDE0071:Simplify interpolation", Justification = "Allocations (string.Concat vs. string.Format)")]
             protected override bool SetResultCore(PhysicalConnection connection, Message message, in RawResult result)
             {
@@ -389,6 +406,9 @@ private sealed class ConditionMessage : Message.CommandKeyBase
                 public readonly Condition Condition;
                 private readonly RedisValue value;
                 private readonly RedisValue value1;
+                private readonly RedisValue value2;
+                private readonly RedisValue value3;
+                private readonly RedisValue value4;
 
                 public ConditionMessage(Condition condition, int db, CommandFlags flags, RedisCommand command, in RedisKey key, in RedisValue value)
                     : base(db, flags, command, key)
@@ -403,6 +423,15 @@ public ConditionMessage(Condition condition, int db, CommandFlags flags, RedisCo
                     this.value1 = value1; // note no assert here
                 }
 
+                // Message with 3 or 4 values not used, therefore not implemented
+                public ConditionMessage(Condition condition, int db, CommandFlags flags, RedisCommand command, in RedisKey key, in RedisValue value, in RedisValue value1, in RedisValue value2, in RedisValue value3, in RedisValue value4)
+                    : this(condition, db, flags, command, key, value, value1)
+                {
+                    this.value2 = value2; // note no assert here
+                    this.value3 = value3; // note no assert here
+                    this.value4 = value4; // note no assert here
+                }
+
                 protected override void WriteImpl(PhysicalConnection physical)
                 {
                     if (value.IsNull)
@@ -412,16 +441,20 @@ protected override void WriteImpl(PhysicalConnection physical)
                     }
                     else
                     {
-                        physical.WriteHeader(command, value1.IsNull ? 2 : 3);
+                        physical.WriteHeader(command, value1.IsNull ? 2 : value2.IsNull ? 3 : value3.IsNull ? 4 : value4.IsNull ? 5 : 6);
                         physical.Write(Key);
                         physical.WriteBulkString(value);
                         if (!value1.IsNull)
-                        {
                             physical.WriteBulkString(value1);
-                        }
+                        if (!value2.IsNull)
+                            physical.WriteBulkString(value2);
+                        if (!value3.IsNull)
+                            physical.WriteBulkString(value3);
+                        if (!value4.IsNull)
+                            physical.WriteBulkString(value4);
                     }
                 }
-                public override int ArgCount => value.IsNull ? 1 : value1.IsNull ? 2 : 3;
+                public override int ArgCount => value.IsNull ? 1 : value1.IsNull ? 2 : value2.IsNull ? 3 : value3.IsNull ? 4 : value4.IsNull ? 5 : 6;
             }
         }
 
@@ -501,6 +534,67 @@ internal override bool TryValidate(in RawResult result, out bool value)
             }
         }
 
+        internal sealed class StartsWithCondition : Condition
+        {
+            /* only usable for RedisType.SortedSet, members of SortedSets are always byte-arrays, expectedStartValue therefore is a byte-array
+               any Encoding and Conversion for the search-sequence has to be executed in calling application
+               working with byte arrays should prevent any encoding within this class, that could distort the comparison */
+
+            private readonly bool expectedResult;
+            private readonly RedisValue prefix;
+            private readonly RedisKey key;
+
+            internal override Condition MapKeys(Func<RedisKey, RedisKey> map) =>
+                new StartsWithCondition(map(key), prefix, expectedResult);
+
+            public StartsWithCondition(in RedisKey key, in RedisValue prefix, bool expectedResult)
+            {
+                if (key.IsNull) throw new ArgumentNullException(nameof(key));
+                if (prefix.IsNull) throw new ArgumentNullException(nameof(prefix));
+                this.key = key;
+                this.prefix = prefix;
+                this.expectedResult = expectedResult;
+            }
+
+            public override string ToString() =>
+                $"{key} {nameof(RedisType.SortedSet)} > {(expectedResult ? " member starting " : " no member starting ")} {prefix} + prefix";
+
+            internal override void CheckCommands(CommandMap commandMap) => commandMap.AssertAvailable(RedisCommand.ZRANGEBYLEX);
+
+            internal override IEnumerable<Message> CreateMessages(int db, IResultBox? resultBox)
+            {
+                yield return Message.Create(db, CommandFlags.None, RedisCommand.WATCH, key);
+
+                // prepend '[' to prefix for inclusive search
+                var startValueWithToken = RedisDatabase.GetLexRange(prefix, Exclude.None, isStart: true, Order.Ascending);
+
+                var message = ConditionProcessor.CreateMessage(
+                    this,
+                    db,
+                    CommandFlags.None,
+                    RedisCommand.ZRANGEBYLEX,
+                    key,
+                    startValueWithToken,
+                    RedisLiterals.PlusSymbol,
+                    RedisLiterals.LIMIT,
+                    0,
+                    1);
+
+                message.SetSource(ConditionProcessor.Default, resultBox);
+                yield return message;
+            }
+
+            internal override int GetHashSlot(ServerSelectionStrategy serverSelectionStrategy) => serverSelectionStrategy.HashSlot(key);
+
+            internal override bool TryValidate(in RawResult result, out bool value)
+            {
+                value = result.ItemsCount == 1 && result[0].AsRedisValue().StartsWith(prefix);
+
+                if (!expectedResult) value = !value;
+                return true;
+            }
+        }
+
         internal sealed class EqualsCondition : Condition
         {
             internal override Condition MapKeys(Func<RedisKey, RedisKey> map) =>

src/StackExchange.Redis/FrameworkShims.cs

@@ -0,0 +1,39 @@
+#pragma warning disable SA1403 // single namespace
+
+#if NET5_0_OR_GREATER
+// context: https://github.com/StackExchange/StackExchange.Redis/issues/2619
+[assembly: System.Runtime.CompilerServices.TypeForwardedTo(typeof(System.Runtime.CompilerServices.IsExternalInit))]
+#else
+// To support { get; init; } properties
+using System.ComponentModel;
+using System.Text;
+
+namespace System.Runtime.CompilerServices
+{
+    [EditorBrowsable(EditorBrowsableState.Never)]
+    internal static class IsExternalInit { }
+}
+#endif
+
+#if !(NETCOREAPP || NETSTANDARD2_1_OR_GREATER)
+
+namespace System.Text
+{
+    internal static class EncodingExtensions
+    {
+        public static unsafe int GetBytes(this Encoding encoding, ReadOnlySpan<char> source, Span<byte> destination)
+        {
+            fixed (byte* bPtr = destination)
+            {
+                fixed (char* cPtr = source)
+                {
+                    return encoding.GetBytes(cPtr, source.Length, bPtr, destination.Length);
+                }
+            }
+        }
+    }
+}
+#endif
+
+
+#pragma warning restore SA1403

src/StackExchange.Redis/Hacks.cs

@@ -1951,4 +1951,8 @@ StackExchange.Redis.IDatabaseAsync.HashFieldSetAndSetExpiryAsync(StackExchange.R
 StackExchange.Redis.IDatabaseAsync.HashFieldSetAndSetExpiryAsync(StackExchange.Redis.RedisKey key, StackExchange.Redis.RedisValue field, StackExchange.Redis.RedisValue value, System.TimeSpan? expiry = null, bool keepTtl = false, StackExchange.Redis.When when = StackExchange.Redis.When.Always, StackExchange.Redis.CommandFlags flags = StackExchange.Redis.CommandFlags.None) -> System.Threading.Tasks.Task<StackExchange.Redis.RedisValue>!
 StackExchange.Redis.IDatabaseAsync.HashFieldSetAndSetExpiryAsync(StackExchange.Redis.RedisKey key, StackExchange.Redis.HashEntry[]! hashFields, System.DateTime expiry, StackExchange.Redis.When when = StackExchange.Redis.When.Always, StackExchange.Redis.CommandFlags flags = StackExchange.Redis.CommandFlags.None) -> System.Threading.Tasks.Task<StackExchange.Redis.RedisValue>!
 StackExchange.Redis.IDatabaseAsync.HashFieldSetAndSetExpiryAsync(StackExchange.Redis.RedisKey key, StackExchange.Redis.HashEntry[]! hashFields, System.TimeSpan? expiry = null, bool keepTtl = false, StackExchange.Redis.When when = StackExchange.Redis.When.Always, StackExchange.Redis.CommandFlags flags = StackExchange.Redis.CommandFlags.None) -> System.Threading.Tasks.Task<StackExchange.Redis.RedisValue>!
-
+StackExchange.Redis.RedisValue.CopyTo(System.Span<byte> destination) -> int
+StackExchange.Redis.RedisValue.GetByteCount() -> int
+StackExchange.Redis.RedisValue.GetLongByteCount() -> long
+static StackExchange.Redis.Condition.SortedSetContainsStarting(StackExchange.Redis.RedisKey key, StackExchange.Redis.RedisValue prefix) -> StackExchange.Redis.Condition!
+static StackExchange.Redis.Condition.SortedSetNotContainsStarting(StackExchange.Redis.RedisKey key, StackExchange.Redis.RedisValue prefix) -> StackExchange.Redis.Condition!

src/StackExchange.Redis/PublicAPI/PublicAPI.Shipped.txt

@@ -1 +1 @@
-#nullable enable
+#nullable enable

src/StackExchange.Redis/PublicAPI/PublicAPI.Unshipped.txt

@@ -3962,21 +3962,23 @@ private Message GetSortedSetMultiPopMessage(RedisKey[] keys, Order order, long c
             return tran;
         }
 
-        private static RedisValue GetLexRange(RedisValue value, Exclude exclude, bool isStart, Order order)
+        internal static RedisValue GetLexRange(RedisValue value, Exclude exclude, bool isStart, Order order)
         {
-            if (value.IsNull)
+            if (value.IsNull) // open search
             {
                 if (order == Order.Ascending) return isStart ? RedisLiterals.MinusSymbol : RedisLiterals.PlusSymbol;
 
-                return isStart ? RedisLiterals.PlusSymbol : RedisLiterals.MinusSymbol; // 24.01.2024: when descending order: Plus and Minus have to be reversed
+                return isStart ? RedisLiterals.PlusSymbol : RedisLiterals.MinusSymbol; // when descending order: Plus and Minus have to be reversed
             }
 
-            byte[] orig = value!;
+            var srcLength = value.GetByteCount();
+            Debug.Assert(srcLength >= 0);
 
-            byte[] result = new byte[orig.Length + 1];
+            byte[] result = new byte[srcLength + 1];
             // no defaults here; must always explicitly specify [ / (
             result[0] = (exclude & (isStart ? Exclude.Start : Exclude.Stop)) == 0 ? (byte)'[' : (byte)'(';
-            Buffer.BlockCopy(orig, 0, result, 1, orig.Length);
+            int written = value.CopyTo(result.AsSpan(1));
+            Debug.Assert(written == srcLength, "predicted/actual length mismatch");
             return result;
         }
 

src/StackExchange.Redis/RedisDatabase.cs

@@ -2,6 +2,7 @@
 using System.Buffers;
 using System.Buffers.Text;
 using System.ComponentModel;
+using System.Diagnostics;
 using System.IO;
 using System.Linq;
 using System.Reflection;
@@ -838,23 +839,78 @@ private static string ToHex(ReadOnlySpan<byte> src)
 
                     return value._memory.ToArray();
                 case StorageType.Int64:
-                    Span<byte> span = stackalloc byte[Format.MaxInt64TextLen + 2];
-                    int len = PhysicalConnection.WriteRaw(span, value.OverlappedValueInt64, false, 0);
-                    arr = new byte[len - 2]; // don't need the CRLF
-                    span.Slice(0, arr.Length).CopyTo(arr);
-                    return arr;
+                    Debug.Assert(Format.MaxInt64TextLen <= 24);
+                    Span<byte> span = stackalloc byte[24];
+                    int len = Format.FormatInt64(value.OverlappedValueInt64, span);
+                    return span.Slice(0, len).ToArray();
                 case StorageType.UInt64:
-                    // we know it is a huge value - just jump straight to Utf8Formatter
-                    span = stackalloc byte[Format.MaxInt64TextLen];
+                    Debug.Assert(Format.MaxInt64TextLen <= 24);
+                    span = stackalloc byte[24];
                     len = Format.FormatUInt64(value.OverlappedValueUInt64, span);
-                    arr = new byte[len];
-                    span.Slice(0, len).CopyTo(arr);
-                    return arr;
+                    return span.Slice(0, len).ToArray();
+                case StorageType.Double:
+                    span = stackalloc byte[128];
+                    len = Format.FormatDouble(value.OverlappedValueDouble, span);
+                    return span.Slice(0, len).ToArray();
+                case StorageType.String:
+                    return Encoding.UTF8.GetBytes((string)value._objectOrSentinel!);
             }
             // fallback: stringify and encode
             return Encoding.UTF8.GetBytes((string)value!);
         }
 
+        /// <summary>
+        /// Gets the length of the value in bytes.
+        /// </summary>
+        public int GetByteCount()
+        {
+            switch (Type)
+            {
+                case StorageType.Null: return 0;
+                case StorageType.Raw: return _memory.Length;
+                case StorageType.String: return Encoding.UTF8.GetByteCount((string)_objectOrSentinel!);
+                case StorageType.Int64: return Format.MeasureInt64(OverlappedValueInt64);
+                case StorageType.UInt64: return Format.MeasureUInt64(OverlappedValueUInt64);
+                case StorageType.Double: return Format.MeasureDouble(OverlappedValueDouble);
+                default: return ThrowUnableToMeasure();
+            }
+        }
+
+        private int ThrowUnableToMeasure() => throw new InvalidOperationException("Unable to compute length of type: " + Type);
+
+        /// <summary>
+        /// Gets the length of the value in bytes.
+        /// </summary>
+        /* right now, we only support int lengths, but adding this now so that
+         there are no surprises if/when we add support for discontiguous buffers */
+        public long GetLongByteCount() => GetByteCount();
+
+        /// <summary>
+        /// Copy the value as bytes to the provided <paramref name="destination"/>.
+        /// </summary>
+        public int CopyTo(Span<byte> destination)
+        {
+            switch (Type)
+            {
+                case StorageType.Null:
+                    return 0;
+                case StorageType.Raw:
+                    var srcBytes = _memory.Span;
+                    srcBytes.CopyTo(destination);
+                    return srcBytes.Length;
+                case StorageType.String:
+                    return Encoding.UTF8.GetBytes(((string)_objectOrSentinel!).AsSpan(), destination);
+                case StorageType.Int64:
+                    return Format.FormatInt64(OverlappedValueInt64, destination);
+                case StorageType.UInt64:
+                    return Format.FormatUInt64(OverlappedValueUInt64, destination);
+                case StorageType.Double:
+                    return Format.FormatDouble(OverlappedValueDouble, destination);
+                default:
+                    return ThrowUnableToMeasure();
+            }
+        }
+
         /// <summary>
         /// Converts a <see cref="RedisValue"/> to a <see cref="ReadOnlyMemory{T}"/>.
         /// </summary>

src/StackExchange.Redis/RedisValue.cs

@@ -51,6 +51,9 @@ public async Task QueryRangeAndLengthByLex()
         set = db.SortedSetRangeByValue(key, "e", default(RedisValue));
         count = db.SortedSetLengthByValue(key, "e", default(RedisValue));
         Equate(set, count, "e", "f", "g");
+
+        set = db.SortedSetRangeByValue(key, RedisValue.Null, RedisValue.Null, Exclude.None, Order.Descending, 0, 3);    // added to test Null-min- and max-param
+        Equate(set, set.Length, "g", "f", "e");
     }
 
     [Fact]