diff --git a/src/ModelContextProtocol.Core/McpJsonUtilities.cs b/src/ModelContextProtocol.Core/McpJsonUtilities.cs index 70eb30d0d..7ee7644c7 100644 --- a/src/ModelContextProtocol.Core/McpJsonUtilities.cs +++ b/src/ModelContextProtocol.Core/McpJsonUtilities.cs @@ -140,6 +140,7 @@ internal static bool IsValidMcpToolSchema(JsonElement element) [JsonSerializable(typeof(PingResult))] [JsonSerializable(typeof(ReadResourceRequestParams))] [JsonSerializable(typeof(ReadResourceResult))] + [JsonSerializable(typeof(CacheScope))] [JsonSerializable(typeof(SetLevelRequestParams))] [JsonSerializable(typeof(SubscribeRequestParams))] [JsonSerializable(typeof(UnsubscribeRequestParams))] diff --git a/src/ModelContextProtocol.Core/Protocol/CacheScope.cs b/src/ModelContextProtocol.Core/Protocol/CacheScope.cs new file mode 100644 index 000000000..d87cdd7f9 --- /dev/null +++ b/src/ModelContextProtocol.Core/Protocol/CacheScope.cs @@ -0,0 +1,44 @@ +using System.Text.Json.Serialization; + +namespace ModelContextProtocol.Protocol; + +/// +/// Indicates the intended scope of a cached response, analogous to the HTTP +/// Cache-Control: public and Cache-Control: private directives. +/// +/// +/// +/// This is used by to control who may cache a +/// response returned by tools/list, prompts/list, resources/list, +/// resources/templates/list, and resources/read. +/// +/// +/// When the field is absent from a response, clients should treat it as . +/// +/// +[JsonConverter(typeof(JsonStringEnumConverter))] +public enum CacheScope +{ + /// + /// The response does not contain user-specific data. Any client, shared gateway, or caching + /// proxy may store and serve the cached response to any user. + /// + /// + /// This is appropriate for lists of tools, prompts, and resource templates that are identical + /// for all users. + /// + [JsonStringEnumMemberName("public")] + Public, + + /// + /// The response contains user-specific data. Only the requesting user's client may cache it. + /// Shared caches (for example, multi-tenant gateways) must not serve the cached response to a + /// different user. + /// + /// + /// This is appropriate for resources/read results that depend on the authenticated user, + /// or for filtered list results that vary per user. + /// + [JsonStringEnumMemberName("private")] + Private +} diff --git a/src/ModelContextProtocol.Core/Protocol/CacheScopeConverter.cs b/src/ModelContextProtocol.Core/Protocol/CacheScopeConverter.cs new file mode 100644 index 000000000..ef61df263 --- /dev/null +++ b/src/ModelContextProtocol.Core/Protocol/CacheScopeConverter.cs @@ -0,0 +1,70 @@ +using System.Text.Json; +using System.Text.Json.Serialization; + +namespace ModelContextProtocol.Protocol; + +/// +/// Serializes caching-scope hints, tolerating unknown or future values on read. +/// +/// +/// +/// SEP-2549 introduces cacheScope as a forward-looking caching hint. If a server sends an +/// unrecognized scope string (for example, a value added in a later revision of the specification) or a +/// non-string token, this converter maps it to rather than throwing. This prevents +/// a single unexpected hint from breaking deserialization of the entire result (for example, the whole +/// tool list). A result is the same as an absent field, which clients treat as +/// . +/// +/// +/// This converter is applied per-property on the cacheable result types. The +/// enum itself retains a standard string converter for any standalone serialization. +/// +/// +internal sealed class CacheScopeConverter : JsonConverter +{ + public override CacheScope? Read(ref Utf8JsonReader reader, Type typeToConvert, JsonSerializerOptions options) + { + if (reader.TokenType is JsonTokenType.String) + { + string? value = reader.GetString(); + + // Match case-insensitively so a non-conforming casing of "private" (a security-relevant hint) + // is honored rather than falling through to null, which clients would treat as "public" and + // could cache user-specific data in a shared cache. Genuinely unknown values still map to null. + if (string.Equals(value, "public", StringComparison.OrdinalIgnoreCase)) + { + return CacheScope.Public; + } + + if (string.Equals(value, "private", StringComparison.OrdinalIgnoreCase)) + { + return CacheScope.Private; + } + + return null; + } + + // Any non-string token (number, bool, object, array) is an unrecognized hint. Consume the whole + // value, including the contents of an object or array, so the reader is left correctly positioned + // before mapping to null. Skipping is required for container tokens: returning without consuming + // them would leave the reader mispositioned and break deserialization of the enclosing result. + reader.Skip(); + return null; + } + + public override void Write(Utf8JsonWriter writer, CacheScope? value, JsonSerializerOptions options) + { + if (value is null) + { + writer.WriteNullValue(); + return; + } + + writer.WriteStringValue(value switch + { + CacheScope.Public => "public", + CacheScope.Private => "private", + _ => throw new JsonException($"Unsupported {nameof(CacheScope)} value: {value}."), + }); + } +} diff --git a/src/ModelContextProtocol.Core/Protocol/ICacheableResult.cs b/src/ModelContextProtocol.Core/Protocol/ICacheableResult.cs new file mode 100644 index 000000000..33169208a --- /dev/null +++ b/src/ModelContextProtocol.Core/Protocol/ICacheableResult.cs @@ -0,0 +1,58 @@ +namespace ModelContextProtocol.Protocol; + +/// +/// Represents a result that carries time-to-live (TTL) caching hints, allowing clients to cache +/// the response for a period of time before re-fetching. +/// +/// +/// +/// This interface corresponds to the CacheableResult type in the Model Context Protocol +/// schema and is implemented by the results of tools/list, prompts/list, +/// resources/list, resources/templates/list, and resources/read. +/// +/// +/// The TTL is a freshness hint, not a guarantee. It supplements rather than replaces the existing +/// list_changed and resources/updated notification mechanisms; both can coexist. A +/// relevant notification invalidates a cached response regardless of any remaining TTL. +/// +/// +public interface ICacheableResult +{ + /// + /// Gets or sets a hint indicating how long the client may cache this response before re-fetching. + /// + /// + /// + /// The semantics are analogous to the HTTP Cache-Control: max-age directive. The value is + /// serialized as an integer number of milliseconds under the ttlMs JSON property. + /// + /// + /// A value of indicates the response should be considered immediately + /// stale; a positive value indicates the client should consider the response fresh for that + /// duration from the time it was received. + /// + /// + /// When this property is (the field was absent from the response), clients + /// should assume a default of (immediately stale) and rely on their + /// own caching heuristics or notifications. A negative value should likewise be treated as + /// . + /// + /// + TimeSpan? TimeToLive { get; set; } + + /// + /// Gets or sets the intended scope of the cached response. + /// + /// + /// + /// When this property is (the field was absent from the response), clients + /// should treat the response as . + /// + /// + /// An unrecognized or future scope value sent by a server (or a non-string value) is tolerated and + /// surfaced as rather than causing deserialization of the whole result to + /// fail, so a single unexpected hint never prevents a client from reading the result. + /// + /// + CacheScope? CacheScope { get; set; } +} diff --git a/src/ModelContextProtocol.Core/Protocol/ListPromptsResult.cs b/src/ModelContextProtocol.Core/Protocol/ListPromptsResult.cs index 1f648bd5a..a7f26b521 100644 --- a/src/ModelContextProtocol.Core/Protocol/ListPromptsResult.cs +++ b/src/ModelContextProtocol.Core/Protocol/ListPromptsResult.cs @@ -18,11 +18,21 @@ namespace ModelContextProtocol.Protocol; /// See the schema for details. /// /// -public sealed class ListPromptsResult : PaginatedResult +public sealed class ListPromptsResult : PaginatedResult, ICacheableResult { /// /// Gets or sets a list of prompts or prompt templates that the server offers. /// [JsonPropertyName("prompts")] public IList Prompts { get; set; } = []; + + /// + [JsonPropertyName("ttlMs")] + [JsonConverter(typeof(TimeSpanMillisecondsConverter))] + public TimeSpan? TimeToLive { get; set; } + + /// + [JsonPropertyName("cacheScope")] + [JsonConverter(typeof(CacheScopeConverter))] + public CacheScope? CacheScope { get; set; } } diff --git a/src/ModelContextProtocol.Core/Protocol/ListResourceTemplatesResult.cs b/src/ModelContextProtocol.Core/Protocol/ListResourceTemplatesResult.cs index 6e422a751..988d6f186 100644 --- a/src/ModelContextProtocol.Core/Protocol/ListResourceTemplatesResult.cs +++ b/src/ModelContextProtocol.Core/Protocol/ListResourceTemplatesResult.cs @@ -20,7 +20,7 @@ namespace ModelContextProtocol.Protocol; /// See the schema for details. /// /// -public sealed class ListResourceTemplatesResult : PaginatedResult +public sealed class ListResourceTemplatesResult : PaginatedResult, ICacheableResult { /// /// Gets or sets a list of resource templates that the server offers. @@ -32,4 +32,14 @@ public sealed class ListResourceTemplatesResult : PaginatedResult /// [JsonPropertyName("resourceTemplates")] public IList ResourceTemplates { get; set; } = []; + + /// + [JsonPropertyName("ttlMs")] + [JsonConverter(typeof(TimeSpanMillisecondsConverter))] + public TimeSpan? TimeToLive { get; set; } + + /// + [JsonPropertyName("cacheScope")] + [JsonConverter(typeof(CacheScopeConverter))] + public CacheScope? CacheScope { get; set; } } \ No newline at end of file diff --git a/src/ModelContextProtocol.Core/Protocol/ListResourcesResult.cs b/src/ModelContextProtocol.Core/Protocol/ListResourcesResult.cs index 16d01491c..54c1df601 100644 --- a/src/ModelContextProtocol.Core/Protocol/ListResourcesResult.cs +++ b/src/ModelContextProtocol.Core/Protocol/ListResourcesResult.cs @@ -18,11 +18,21 @@ namespace ModelContextProtocol.Protocol; /// See the schema for details. /// /// -public sealed class ListResourcesResult : PaginatedResult +public sealed class ListResourcesResult : PaginatedResult, ICacheableResult { /// /// Gets or sets a list of resources that the server offers. /// [JsonPropertyName("resources")] public IList Resources { get; set; } = []; + + /// + [JsonPropertyName("ttlMs")] + [JsonConverter(typeof(TimeSpanMillisecondsConverter))] + public TimeSpan? TimeToLive { get; set; } + + /// + [JsonPropertyName("cacheScope")] + [JsonConverter(typeof(CacheScopeConverter))] + public CacheScope? CacheScope { get; set; } } diff --git a/src/ModelContextProtocol.Core/Protocol/ListToolsResult.cs b/src/ModelContextProtocol.Core/Protocol/ListToolsResult.cs index a2f03b853..55eed5ddb 100644 --- a/src/ModelContextProtocol.Core/Protocol/ListToolsResult.cs +++ b/src/ModelContextProtocol.Core/Protocol/ListToolsResult.cs @@ -18,11 +18,21 @@ namespace ModelContextProtocol.Protocol; /// See the schema for details. /// /// -public sealed class ListToolsResult : PaginatedResult +public sealed class ListToolsResult : PaginatedResult, ICacheableResult { /// /// Gets or sets the server's response to a tools/list request from the client. /// [JsonPropertyName("tools")] public IList Tools { get; set; } = []; + + /// + [JsonPropertyName("ttlMs")] + [JsonConverter(typeof(TimeSpanMillisecondsConverter))] + public TimeSpan? TimeToLive { get; set; } + + /// + [JsonPropertyName("cacheScope")] + [JsonConverter(typeof(CacheScopeConverter))] + public CacheScope? CacheScope { get; set; } } diff --git a/src/ModelContextProtocol.Core/Protocol/ReadResourceResult.cs b/src/ModelContextProtocol.Core/Protocol/ReadResourceResult.cs index 084322fde..53e138806 100644 --- a/src/ModelContextProtocol.Core/Protocol/ReadResourceResult.cs +++ b/src/ModelContextProtocol.Core/Protocol/ReadResourceResult.cs @@ -8,7 +8,7 @@ namespace ModelContextProtocol.Protocol; /// /// See the schema for details. /// -public sealed class ReadResourceResult : Result +public sealed class ReadResourceResult : Result, ICacheableResult { /// /// Gets or sets a list of objects that this resource contains. @@ -20,4 +20,14 @@ public sealed class ReadResourceResult : Result /// [JsonPropertyName("contents")] public IList Contents { get; set; } = []; + + /// + [JsonPropertyName("ttlMs")] + [JsonConverter(typeof(TimeSpanMillisecondsConverter))] + public TimeSpan? TimeToLive { get; set; } + + /// + [JsonPropertyName("cacheScope")] + [JsonConverter(typeof(CacheScopeConverter))] + public CacheScope? CacheScope { get; set; } } diff --git a/src/ModelContextProtocol.Core/Protocol/TimeSpanMillisecondsConverter.cs b/src/ModelContextProtocol.Core/Protocol/TimeSpanMillisecondsConverter.cs index e789db186..18386d326 100644 --- a/src/ModelContextProtocol.Core/Protocol/TimeSpanMillisecondsConverter.cs +++ b/src/ModelContextProtocol.Core/Protocol/TimeSpanMillisecondsConverter.cs @@ -10,7 +10,10 @@ namespace ModelContextProtocol.Protocol; /// /// This converter serializes TimeSpan values as the total number of milliseconds (as an integer), /// and deserializes integer millisecond values back to TimeSpan. System.Text.Json automatically -/// handles nullable TimeSpan properties using this converter. +/// handles nullable TimeSpan properties using this converter. Millisecond values that fall outside +/// the range representable by are clamped to +/// / rather than throwing, so an +/// oversized or malformed hint can never break deserialization of the enclosing result. /// [EditorBrowsable(EditorBrowsableState.Never)] public sealed class TimeSpanMillisecondsConverter : JsonConverter @@ -22,17 +25,93 @@ public override TimeSpan Read(ref Utf8JsonReader reader, Type typeToConvert, Jso { if (reader.TryGetInt64(out long milliseconds)) { - return TimeSpan.FromMilliseconds(milliseconds); + return FromMillisecondsClamped(milliseconds); } - // For non-integer values, convert from fractional milliseconds - double fractionalMilliseconds = reader.GetDouble(); - return TimeSpan.FromTicks((long)(fractionalMilliseconds * TimeSpan.TicksPerMillisecond)); + // Non-integer value: fractional, or a magnitude too large to represent. Use the non-throwing + // TryGetDouble so an out-of-range exponent never breaks deserialization. Note that different + // runtimes disagree on out-of-range doubles: in-box .NET returns +/-Infinity, whereas .NET + // Framework's parser reports failure. Handle both so behavior is identical everywhere. + if (reader.TryGetDouble(out double value)) + { + if (double.IsPositiveInfinity(value)) + { + return TimeSpan.MaxValue; + } + + if (double.IsNegativeInfinity(value)) + { + return TimeSpan.MinValue; + } + + return FromTicksClamped(value * TimeSpan.TicksPerMillisecond); + } + + // The runtime could not represent the number as a double at all (e.g. .NET Framework on an + // overflowing exponent). Clamp by the sign of the raw token. + return IsNegativeNumberToken(ref reader) ? TimeSpan.MinValue : TimeSpan.MaxValue; } throw new JsonException($"Unable to convert {reader.TokenType} to TimeSpan."); } + private static bool IsNegativeNumberToken(ref Utf8JsonReader reader) + { + ReadOnlySpan token = reader.HasValueSequence ? reader.ValueSequence.First.Span : reader.ValueSpan; + return !token.IsEmpty && token[0] == (byte)'-'; + } + + // Largest whole-millisecond count representable as a TimeSpan (TimeSpan.MaxValue.Ticks / TicksPerMillisecond). + private const long MaxWholeMilliseconds = long.MaxValue / TimeSpan.TicksPerMillisecond; + + // Converts an integer millisecond count to a TimeSpan, clamping out-of-range values to + // TimeSpan.MinValue/MaxValue instead of throwing. A malformed or oversized hint (for example a + // hostile or buggy server returning an enormous ttlMs) must never break deserialization of the + // whole result; per SEP-2549 clients should handle unexpected TTL values gracefully. + private static TimeSpan FromMillisecondsClamped(long milliseconds) + { + if (milliseconds > MaxWholeMilliseconds) + { + return TimeSpan.MaxValue; + } + + if (milliseconds < -MaxWholeMilliseconds) + { + return TimeSpan.MinValue; + } + + return TimeSpan.FromTicks(milliseconds * TimeSpan.TicksPerMillisecond); + } + + // Converts a (possibly fractional or out-of-range) tick count to a TimeSpan, clamping instead of + // throwing. The caller passes a value already scaled into tick-space (milliseconds * TicksPerMillisecond) + // because TimeSpan is backed by a long tick count, so comparing against long.MaxValue/MinValue is the + // exact test for whether the final (long) cast would overflow. The comparisons MUST run before that cast: + // double arithmetic saturates to +/-Infinity on overflow rather than throwing, and both infinities fall + // into the clamp branches here (+Infinity >= long.MaxValue, -Infinity <= long.MinValue); if Infinity + // instead reached "(long)ticks" the unchecked conversion would silently yield long.MinValue. NaN is not + // reachable from valid JSON (the only multiplicand is a non-zero constant) but is mapped to zero + // defensively so a non-numeric hint can never break deserialization. + private static TimeSpan FromTicksClamped(double ticks) + { + if (double.IsNaN(ticks)) + { + return TimeSpan.Zero; + } + + if (ticks >= long.MaxValue) + { + return TimeSpan.MaxValue; + } + + if (ticks <= long.MinValue) + { + return TimeSpan.MinValue; + } + + return TimeSpan.FromTicks((long)ticks); + } + /// public override void Write(Utf8JsonWriter writer, TimeSpan value, JsonSerializerOptions options) { diff --git a/tests/Common/Utils/NodeHelpers.cs b/tests/Common/Utils/NodeHelpers.cs index a30dd3fc3..b3b10bab6 100644 --- a/tests/Common/Utils/NodeHelpers.cs +++ b/tests/Common/Utils/NodeHelpers.cs @@ -1,5 +1,7 @@ using System.Diagnostics; using System.Runtime.InteropServices; +using System.Text; +using System.Text.RegularExpressions; namespace ModelContextProtocol.Tests.Utils; @@ -78,16 +80,25 @@ public static void EnsureNpmDependenciesInstalled() /// /// The name of the binary in node_modules/.bin (e.g. "conformance"). /// The arguments to pass to the binary. + /// + /// When (the default) and the MCP_CONFORMANCE_PROTOCOL_VERSION + /// environment variable is set, a "--spec-version <value>" argument is appended. + /// Pass for scenarios that pin their own spec version (e.g. the + /// draft-only caching scenario) to avoid a conflicting duplicate flag. + /// /// A configured ProcessStartInfo for running the binary. - public static ProcessStartInfo ConformanceTestStartInfo(string arguments) + public static ProcessStartInfo ConformanceTestStartInfo(string arguments, bool appendProtocolVersionFromEnv = true) { EnsureNpmDependenciesInstalled(); // If MCP_CONFORMANCE_PROTOCOL_VERSION is set, pass it as --spec-version to the runner. - var protocolVersion = Environment.GetEnvironmentVariable("MCP_CONFORMANCE_PROTOCOL_VERSION"); - if (!string.IsNullOrEmpty(protocolVersion)) + if (appendProtocolVersionFromEnv) { - arguments += $" --spec-version {protocolVersion}"; + var protocolVersion = Environment.GetEnvironmentVariable("MCP_CONFORMANCE_PROTOCOL_VERSION"); + if (!string.IsNullOrEmpty(protocolVersion)) + { + arguments += $" --spec-version {protocolVersion}"; + } } var repoRoot = FindRepoRoot(); @@ -168,41 +179,197 @@ public static bool IsNodeInstalled() } /// - /// Checks whether the SEP-2243 conformance scenarios are available by reading - /// the conformance package version from the repo's package.json. + /// Checks whether the SEP-2243 conformance scenarios are available, by reading the + /// installed conformance package version from node_modules. /// The http-standard-headers, http-custom-headers, http-invalid-tool-headers, - /// http-header-validation, and http-custom-header-server-validation scenarios - /// require a conformance package version that includes SEP-2243 support. + /// http-header-validation, and http-custom-header-server-validation scenarios were + /// introduced in conformance package 0.2.0. Reading the installed version (rather than + /// the pinned version in package.json) means this also returns + /// when a newer private build has been installed locally via + /// npm install --no-save <path-to-conformance>. + /// + public static bool HasSep2243Scenarios() => HasInstalledConformanceVersionAtLeast(new Version(0, 2, 0)); + + /// + /// Checks whether the SEP-2549 "caching" conformance scenario (added in conformance + /// PR #275) is available, by reading the installed conformance package version + /// from node_modules. The caching scenario was introduced in conformance package 0.2.0. + /// Reading the installed version (rather than the pinned version in package.json) means + /// this also returns when a newer private build has been installed + /// locally via npm install --no-save <path-to-conformance>. + /// + public static bool HasCachingScenario() => HasInstalledConformanceVersionAtLeast(new Version(0, 2, 0)); + + /// + /// Returns when the conformance package installed in node_modules + /// has a version greater than or equal to . /// - public static bool HasSep2243Scenarios() + private static bool HasInstalledConformanceVersionAtLeast(Version minimumVersion) + { + var version = GetInstalledConformanceVersion(); + return version is not null && version >= minimumVersion; + } + + /// + /// Reads the version of the conformance package actually installed in node_modules, + /// stripping any prerelease/build suffix (e.g. "0.2.0-alpha.1" -> "0.2.0") so it can be + /// parsed as a . Returns if it cannot be + /// determined. + /// + private static Version? GetInstalledConformanceVersion() { try { var repoRoot = FindRepoRoot(); - var packageJsonPath = Path.Combine(repoRoot, "package.json"); + var packageJsonPath = Path.Combine( + repoRoot, "node_modules", "@modelcontextprotocol", "conformance", "package.json"); + + // This is a skip gate for version-conditional conformance scenarios, so it must stay + // side-effect-free. If the conformance package isn't installed, report no version (the + // scenario is simply gated off); the actual scenario run path restores npm dependencies + // separately via ConformanceTestStartInfo. if (!File.Exists(packageJsonPath)) { - return false; + return null; } - var json = System.Text.Json.JsonDocument.Parse(File.ReadAllText(packageJsonPath)); - if (json.RootElement.TryGetProperty("dependencies", out var deps) && - deps.TryGetProperty("@modelcontextprotocol/conformance", out var versionElement)) + using var json = System.Text.Json.JsonDocument.Parse(File.ReadAllText(packageJsonPath)); + if (json.RootElement.TryGetProperty("version", out var versionElement) && + versionElement.GetString() is { } versionStr) { - var versionStr = versionElement.GetString(); - if (versionStr is not null && Version.TryParse(versionStr, out var version)) + // Strip any prerelease/build suffix so System.Version can parse it. + var core = versionStr.Split('-', '+')[0]; + if (Version.TryParse(core, out var version)) { - // SEP-2243 scenarios are expected in conformance package >= 0.2.0 - return version >= new Version(0, 2, 0); + return version; } } - return false; + return null; } catch + { + return null; + } + } + + /// + /// Runs the conformance runner ("conformance <arguments>") in server mode and returns + /// whether it succeeded along with the captured stdout/stderr. Centralizes the process + /// plumbing (output capture, a 5-minute timeout, and the Windows libuv-shutdown fallback) + /// shared by the server-side conformance tests. + /// + /// Arguments to pass to the conformance runner. + /// Optional callback invoked for each captured stdout/stderr line. + /// + /// Forwarded to . + /// + /// Token used to cancel the run. + public static async Task<(bool Success, string Output, string Error)> RunServerConformanceAsync( + string arguments, + Action? onLine = null, + bool appendProtocolVersionFromEnv = true, + CancellationToken cancellationToken = default) + { + var startInfo = ConformanceTestStartInfo(arguments, appendProtocolVersionFromEnv); + + var outputBuilder = new StringBuilder(); + var errorBuilder = new StringBuilder(); + + using var process = new Process { StartInfo = startInfo }; + + // Protect callbacks with try/catch so a callback that throws on a background thread + // (e.g. ITestOutputHelper after the test completes) does not crash the test host. + DataReceivedEventHandler outputHandler = (sender, e) => + { + if (e.Data != null) + { + try { onLine?.Invoke(e.Data); } catch { } + outputBuilder.AppendLine(e.Data); + } + }; + + DataReceivedEventHandler errorHandler = (sender, e) => + { + if (e.Data != null) + { + try { onLine?.Invoke(e.Data); } catch { } + errorBuilder.AppendLine(e.Data); + } + }; + + process.OutputDataReceived += outputHandler; + process.ErrorDataReceived += errorHandler; + + process.Start(); + process.BeginOutputReadLine(); + process.BeginErrorReadLine(); + + using var cts = CancellationTokenSource.CreateLinkedTokenSource(cancellationToken); + cts.CancelAfter(TimeSpan.FromMinutes(5)); + try + { +#if NET + await process.WaitForExitAsync(cts.Token); +#else + // net472 lacks the CancellationToken overload; fall back to the timeout-based polyfill + // extension and surface a timeout the same way the modern path does. + await process.WaitForExitAsync(TimeSpan.FromMinutes(5)); + if (!process.HasExited) + { + throw new OperationCanceledException(); + } +#endif + } + catch (OperationCanceledException) + { +#if NET + process.Kill(entireProcessTree: true); +#else + process.Kill(); +#endif + process.OutputDataReceived -= outputHandler; + process.ErrorDataReceived -= errorHandler; + return ( + false, + outputBuilder.ToString(), + errorBuilder.ToString() + "\nProcess timed out after 5 minutes and was killed."); + } + + process.OutputDataReceived -= outputHandler; + process.ErrorDataReceived -= errorHandler; + + var stdoutText = outputBuilder.ToString(); + var stderrText = errorBuilder.ToString(); + + // The Node.js conformance runner can crash during cleanup on Windows with a libuv + // assertion ("!(handle->flags & UV_HANDLE_CLOSING)") that produces a non-zero exit + // code even though every conformance check passed. When that happens, fall back to + // parsing the "Test Results:" summary in stdout to decide success. + bool success = process.ExitCode == 0 || ConformanceOutputIndicatesSuccess(stdoutText); + + return (success, stdoutText, stderrText); + } + + /// + /// Parses the conformance runner output for a "Test Results:" line such as + /// "Passed: 3/3, 0 failed, 0 warnings" and returns true when all checks passed + /// and none failed. + /// + private static bool ConformanceOutputIndicatesSuccess(string output) + { + // Match lines like "Passed: 3/3, 0 failed, 0 warnings" + var match = Regex.Match(output, @"Passed:\s*(\d+)/(\d+),\s*(\d+)\s*failed"); + if (!match.Success) { return false; } + + int passed = int.Parse(match.Groups[1].Value); + int total = int.Parse(match.Groups[2].Value); + int failed = int.Parse(match.Groups[3].Value); + + return passed == total && failed == 0 && total > 0; } private static ProcessStartInfo NpmStartInfo(string arguments, string workingDirectory) diff --git a/tests/ModelContextProtocol.AspNetCore.Tests/CachingConformanceTests.cs b/tests/ModelContextProtocol.AspNetCore.Tests/CachingConformanceTests.cs new file mode 100644 index 000000000..5cdd2948a --- /dev/null +++ b/tests/ModelContextProtocol.AspNetCore.Tests/CachingConformanceTests.cs @@ -0,0 +1,139 @@ +using System.Diagnostics; +using ModelContextProtocol.Tests.Utils; + +namespace ModelContextProtocol.ConformanceTests; + +/// +/// A ConformanceServer instance started in the SEP-2575 stateless lifecycle, which the draft +/// SEP-2549 "caching" conformance scenario requires. Started on demand (so it is not bound +/// when the caching test is skipped) and torn down via . Uses a +/// distinct port range from the stateful ConformanceServerFixture (3001/3002/3003) so +/// the two can run in parallel without TCP conflicts. +/// +internal sealed class StatelessConformanceServer : IAsyncDisposable +{ + // Use different ports for each target framework to allow parallel execution across the + // multi-targeted test processes, offset from a caller-supplied base port so independent + // stateless servers (e.g. caching vs. SEP-2243) do not collide. net10.0 -> +0, + // net9.0 -> +1, net8.0 -> +2. + private static int GetPortForTargetFramework(int basePort) + { + var testBinaryDir = AppContext.BaseDirectory; + var targetFramework = Path.GetFileName(testBinaryDir.TrimEnd(Path.DirectorySeparatorChar)); + + var offset = targetFramework switch + { + "net10.0" => 0, + "net9.0" => 1, + "net8.0" => 2, + _ => 0 // Default fallback + }; + + return basePort + offset; + } + + private readonly Task _serverTask; + private readonly CancellationTokenSource _serverCts; + + public string ServerUrl { get; } + + private StatelessConformanceServer(string serverUrl, Task serverTask, CancellationTokenSource serverCts) + { + ServerUrl = serverUrl; + _serverTask = serverTask; + _serverCts = serverCts; + } + + public static async Task StartAsync(CancellationToken cancellationToken, int basePort = 3011) + { + var serverUrl = $"http://localhost:{GetPortForTargetFramework(basePort)}"; + var serverCts = CancellationTokenSource.CreateLinkedTokenSource(cancellationToken); + + // "--stateless true" opts this server instance into the SEP-2575 stateless lifecycle + // (see ConformanceServer.Program), without mutating process-wide environment state. + var serverTask = Task.Run(() => ConformanceServer.Program.MainAsync( + ["--urls", serverUrl, "--stateless", "true"], cancellationToken: serverCts.Token)); + + // Wait for the server to be ready (retry for up to 30 seconds). + var timeout = TimeSpan.FromSeconds(30); + var stopwatch = Stopwatch.StartNew(); + using var httpClient = new HttpClient { Timeout = TestConstants.HttpClientPollingTimeout }; + + while (stopwatch.Elapsed < timeout) + { + try + { + await httpClient.GetAsync($"{serverUrl}/health", cancellationToken); + return new StatelessConformanceServer(serverUrl, serverTask, serverCts); + } + catch (HttpRequestException) + { + // Connection refused means the server is not ready yet. + } + catch (TaskCanceledException) + { + // Timeout means the server might be processing; give it more time. + } + + await Task.Delay(500, cancellationToken); + } + + serverCts.Cancel(); + serverCts.Dispose(); + throw new InvalidOperationException("Stateless ConformanceServer failed to start within the timeout period"); + } + + public async ValueTask DisposeAsync() + { + _serverCts.Cancel(); + try + { + await _serverTask.WaitAsync(TestConstants.DefaultTimeout); + } + catch + { + // Ignore exceptions during shutdown. + } + _serverCts.Dispose(); + } +} + +/// +/// Runs the official MCP conformance "caching" scenario (SEP-2549: TTL for List Results, +/// added in conformance PR #275) against the SDK's ConformanceServer, verifying that the SDK +/// correctly emits the ttlMs and cacheScope caching hints on cacheable results +/// (tools/list, prompts/list, resources/list, resources/templates/list, resources/read). +/// +/// +/// The scenario is draft-only (introduced in DRAFT-2026-v1) and uses the stateless lifecycle. +/// It is gated on the installed conformance package version (>= 0.2.0) and is skipped when +/// running against the currently-pinned package, so it activates automatically once a +/// conformance package containing the caching scenario is installed (including a local private +/// build installed via npm install --no-save <path-to-conformance>). The stateless +/// server is started only after the gates pass, so a skipped run binds no port. +/// +public class CachingConformanceTests(ITestOutputHelper output) +{ + [Fact] + public async Task RunCachingConformanceTest() + { + Assert.SkipWhen(!NodeHelpers.IsNodeInstalled(), "Node.js is not installed. Skipping conformance tests."); + Assert.SkipWhen( + !NodeHelpers.HasCachingScenario(), + "SEP-2549 caching conformance scenario not available (requires conformance package >= 0.2.0)."); + + await using var server = await StatelessConformanceServer.StartAsync(TestContext.Current.CancellationToken); + + // The caching scenario only exists in the draft spec, so pin the spec version + // explicitly (and suppress the MCP_CONFORMANCE_PROTOCOL_VERSION override to avoid a + // conflicting duplicate --spec-version flag). + var result = await NodeHelpers.RunServerConformanceAsync( + $"server --url {server.ServerUrl} --scenario caching --spec-version DRAFT-2026-v1", + line => { try { output.WriteLine(line); } catch { } }, + appendProtocolVersionFromEnv: false, + cancellationToken: TestContext.Current.CancellationToken); + + Assert.True(result.Success, + $"SEP-2549 caching conformance test failed.\n\nStdout:\n{result.Output}\n\nStderr:\n{result.Error}"); + } +} diff --git a/tests/ModelContextProtocol.AspNetCore.Tests/ClientConformanceTests.cs b/tests/ModelContextProtocol.AspNetCore.Tests/ClientConformanceTests.cs index 7b2be118b..f389ffbba 100644 --- a/tests/ModelContextProtocol.AspNetCore.Tests/ClientConformanceTests.cs +++ b/tests/ModelContextProtocol.AspNetCore.Tests/ClientConformanceTests.cs @@ -63,7 +63,7 @@ public async Task RunConformanceTest(string scenario) } // HTTP Standardization (SEP-2243) - [Theory(Skip = "SEP-2243 conformance scenarios not yet available.", SkipUnless = nameof(HasSep2243Scenarios))] + [Theory(Skip = "SEP-2243 conformance scenarios not available (requires conformance package >= 0.2.0).", SkipUnless = nameof(HasSep2243Scenarios))] [InlineData("http-standard-headers")] [InlineData("http-custom-headers")] [InlineData("http-invalid-tool-headers")] diff --git a/tests/ModelContextProtocol.AspNetCore.Tests/ServerConformanceTests.cs b/tests/ModelContextProtocol.AspNetCore.Tests/ServerConformanceTests.cs index 98cc5971a..83481a76c 100644 --- a/tests/ModelContextProtocol.AspNetCore.Tests/ServerConformanceTests.cs +++ b/tests/ModelContextProtocol.AspNetCore.Tests/ServerConformanceTests.cs @@ -1,7 +1,5 @@ using System.Diagnostics; using System.Runtime.InteropServices; -using System.Text; -using System.Text.RegularExpressions; using ModelContextProtocol.Tests.Utils; namespace ModelContextProtocol.ConformanceTests; @@ -37,8 +35,10 @@ private static int GetPortForTargetFramework() public async ValueTask InitializeAsync() { _serverCts = new CancellationTokenSource(); + // Explicitly pass "--stateless false" so this stateful fixture is immune to a globally + // set MCP_CONFORMANCE_STATELESS environment variable (the command-line switch wins). _serverTask = Task.Run(() => ConformanceServer.Program.MainAsync( - ["--urls", ServerUrl], cancellationToken: _serverCts.Token)); + ["--urls", ServerUrl, "--stateless", "false"], cancellationToken: _serverCts.Token)); // Wait for server to be ready (retry for up to 30 seconds) var timeout = TimeSpan.FromSeconds(30); @@ -139,9 +139,19 @@ public async Task RunPendingConformanceTest_ServerSsePolling() public async Task RunConformanceTest_HttpHeaderValidation() { Assert.SkipWhen(!NodeHelpers.IsNodeInstalled(), "Node.js is not installed. Skipping conformance tests."); - Assert.SkipWhen(!NodeHelpers.HasSep2243Scenarios(), "SEP-2243 conformance scenarios not yet available."); + Assert.SkipWhen( + !NodeHelpers.HasSep2243Scenarios(), + "SEP-2243 conformance scenarios not available (requires conformance package >= 0.2.0)."); + + // SEP-2243 is a draft (DRAFT-2026-v1) scenario that uses the stateless lifecycle, so it + // requires a stateless server (a stateful server rejects the un-initialized list/call + // requests with JSON-RPC -32000). Use a dedicated port range so it never collides with + // the stateful class fixture (300x) or the caching stateless server (301x). + await using var server = await StatelessConformanceServer.StartAsync( + TestContext.Current.CancellationToken, basePort: 3021); - var result = await RunConformanceTestsAsync($"server --url {fixture.ServerUrl} --scenario http-header-validation"); + var result = await RunStatelessConformanceTestAsync( + $"server --url {server.ServerUrl} --scenario http-header-validation --spec-version DRAFT-2026-v1"); Assert.True(result.Success, $"Conformance test failed.\n\nStdout:\n{result.Output}\n\nStderr:\n{result.Error}"); @@ -151,9 +161,15 @@ public async Task RunConformanceTest_HttpHeaderValidation() public async Task RunConformanceTest_HttpCustomHeaderServerValidation() { Assert.SkipWhen(!NodeHelpers.IsNodeInstalled(), "Node.js is not installed. Skipping conformance tests."); - Assert.SkipWhen(!NodeHelpers.HasSep2243Scenarios(), "SEP-2243 conformance scenarios not yet available."); + Assert.SkipWhen( + !NodeHelpers.HasSep2243Scenarios(), + "SEP-2243 conformance scenarios not available (requires conformance package >= 0.2.0)."); + + await using var server = await StatelessConformanceServer.StartAsync( + TestContext.Current.CancellationToken, basePort: 3024); - var result = await RunConformanceTestsAsync($"server --url {fixture.ServerUrl} --scenario http-custom-header-server-validation"); + var result = await RunStatelessConformanceTestAsync( + $"server --url {server.ServerUrl} --scenario http-custom-header-server-validation --spec-version DRAFT-2026-v1"); Assert.True(result.Success, $"Conformance test failed.\n\nStdout:\n{result.Output}\n\nStderr:\n{result.Error}"); @@ -161,94 +177,20 @@ public async Task RunConformanceTest_HttpCustomHeaderServerValidation() private async Task<(bool Success, string Output, string Error)> RunConformanceTestsAsync(string arguments) { - var startInfo = NodeHelpers.ConformanceTestStartInfo(arguments); - - var outputBuilder = new StringBuilder(); - var errorBuilder = new StringBuilder(); - - var process = new Process { StartInfo = startInfo }; - - // Protect callbacks with try/catch to prevent ITestOutputHelper from - // throwing on a background thread if events arrive after the test completes. - DataReceivedEventHandler outputHandler = (sender, e) => - { - if (e.Data != null) - { - try { output.WriteLine(e.Data); } catch { } - outputBuilder.AppendLine(e.Data); - } - }; - - DataReceivedEventHandler errorHandler = (sender, e) => - { - if (e.Data != null) - { - try { output.WriteLine(e.Data); } catch { } - errorBuilder.AppendLine(e.Data); - } - }; - - process.OutputDataReceived += outputHandler; - process.ErrorDataReceived += errorHandler; - - process.Start(); - process.BeginOutputReadLine(); - process.BeginErrorReadLine(); - - using var cts = new CancellationTokenSource(TimeSpan.FromMinutes(5)); - try - { - await process.WaitForExitAsync(cts.Token); - } - catch (OperationCanceledException) - { - process.Kill(entireProcessTree: true); - process.OutputDataReceived -= outputHandler; - process.ErrorDataReceived -= errorHandler; - return ( - Success: false, - Output: outputBuilder.ToString(), - Error: errorBuilder.ToString() + "\nProcess timed out after 5 minutes and was killed." - ); - } - - process.OutputDataReceived -= outputHandler; - process.ErrorDataReceived -= errorHandler; - - var stdoutText = outputBuilder.ToString(); - var stderrText = errorBuilder.ToString(); - - // The Node.js conformance runner can crash during cleanup on Windows with a libuv - // assertion ("!(handle->flags & UV_HANDLE_CLOSING)") that produces a non-zero exit - // code even though every conformance check passed. When that happens, fall back to - // parsing the "Test Results:" summary in stdout to decide success. - bool success = process.ExitCode == 0 || ConformanceOutputIndicatesSuccess(stdoutText); - - return ( - Success: success, - Output: stdoutText, - Error: stderrText - ); + return await NodeHelpers.RunServerConformanceAsync( + arguments, + line => { try { output.WriteLine(line); } catch { } }, + cancellationToken: TestContext.Current.CancellationToken); } - /// - /// Parses the conformance runner output for a "Test Results:" line such as - /// "Passed: 3/3, 0 failed, 0 warnings" and returns true when all checks passed - /// and none failed. - /// - private static bool ConformanceOutputIndicatesSuccess(string output) + // For draft scenarios that pin --spec-version explicitly, suppress the + // MCP_CONFORMANCE_PROTOCOL_VERSION override so a duplicate --spec-version is not appended. + private async Task<(bool Success, string Output, string Error)> RunStatelessConformanceTestAsync(string arguments) { - // Match lines like "Passed: 3/3, 0 failed, 0 warnings" - var match = Regex.Match(output, @"Passed:\s*(\d+)/(\d+),\s*(\d+)\s*failed"); - if (!match.Success) - { - return false; - } - - int passed = int.Parse(match.Groups[1].Value); - int total = int.Parse(match.Groups[2].Value); - int failed = int.Parse(match.Groups[3].Value); - - return passed == total && failed == 0 && total > 0; + return await NodeHelpers.RunServerConformanceAsync( + arguments, + line => { try { output.WriteLine(line); } catch { } }, + appendProtocolVersionFromEnv: false, + cancellationToken: TestContext.Current.CancellationToken); } } diff --git a/tests/ModelContextProtocol.ConformanceServer/Program.cs b/tests/ModelContextProtocol.ConformanceServer/Program.cs index 017ec235f..4c8c97887 100644 --- a/tests/ModelContextProtocol.ConformanceServer/Program.cs +++ b/tests/ModelContextProtocol.ConformanceServer/Program.cs @@ -25,10 +25,25 @@ public static async Task MainAsync(string[] args, ILoggerProvider? loggerProvide // because .NET does not have a built-in concurrent HashSet ConcurrentDictionary> subscriptions = new(); + // Allow running the server in the SEP-2575 stateless lifecycle, which the draft + // "caching" (SEP-2549) conformance scenario requires. A "--stateless true|false" + // command-line switch (read via configuration) takes precedence so an in-process test + // fixture can opt in or out per-instance deterministically; when it is not supplied, + // fall back to the MCP_CONFORMANCE_STATELESS environment variable for standalone runs. + // The default (no switch, no env var) remains the stateful server that serves the + // active conformance suite unchanged. + var statelessConfig = builder.Configuration["stateless"]; + var stateless = statelessConfig is not null + ? string.Equals(statelessConfig, "true", StringComparison.OrdinalIgnoreCase) + : string.Equals( + Environment.GetEnvironmentVariable("MCP_CONFORMANCE_STATELESS"), + "true", + StringComparison.OrdinalIgnoreCase); + builder.Services.AddDistributedMemoryCache(); builder.Services .AddMcpServer() - .WithHttpTransport() + .WithHttpTransport(options => options.Stateless = stateless) .WithDistributedCacheEventStreamStore() .WithTools() .WithTools([ConformanceTools.CreateJsonSchema202012Tool()]) @@ -44,6 +59,44 @@ public static async Task MainAsync(string[] args, ILoggerProvider? loggerProvide await request.EnablePollingAsync(TimeSpan.FromMilliseconds(500), cancellationToken); } + return result; + }) + // SEP-2549: advertise TTL/cacheScope caching hints on cacheable results. The + // conformance server's tools, prompts, resources, and resource templates are the + // same for every caller, so they are cacheable with a "public" scope. + .AddListToolsFilter(next => async (request, cancellationToken) => + { + var result = await next(request, cancellationToken); + result.TimeToLive = TimeSpan.FromMinutes(5); + result.CacheScope = CacheScope.Public; + return result; + }) + .AddListPromptsFilter(next => async (request, cancellationToken) => + { + var result = await next(request, cancellationToken); + result.TimeToLive = TimeSpan.FromMinutes(5); + result.CacheScope = CacheScope.Public; + return result; + }) + .AddListResourcesFilter(next => async (request, cancellationToken) => + { + var result = await next(request, cancellationToken); + result.TimeToLive = TimeSpan.FromMinutes(5); + result.CacheScope = CacheScope.Public; + return result; + }) + .AddListResourceTemplatesFilter(next => async (request, cancellationToken) => + { + var result = await next(request, cancellationToken); + result.TimeToLive = TimeSpan.FromMinutes(5); + result.CacheScope = CacheScope.Public; + return result; + }) + .AddReadResourceFilter(next => async (request, cancellationToken) => + { + var result = await next(request, cancellationToken); + result.TimeToLive = TimeSpan.FromMinutes(1); + result.CacheScope = CacheScope.Public; return result; })) .WithPrompts() diff --git a/tests/ModelContextProtocol.Tests/Protocol/CacheableResultClientServerTests.cs b/tests/ModelContextProtocol.Tests/Protocol/CacheableResultClientServerTests.cs new file mode 100644 index 000000000..38e690d07 --- /dev/null +++ b/tests/ModelContextProtocol.Tests/Protocol/CacheableResultClientServerTests.cs @@ -0,0 +1,57 @@ +using Microsoft.Extensions.DependencyInjection; +using ModelContextProtocol.Client; +using ModelContextProtocol.Protocol; +using ModelContextProtocol.Server; + +namespace ModelContextProtocol.Tests.Protocol; + +/// +/// End-to-end tests verifying that SEP-2549 caching hints set by a server on cacheable results +/// are observed by a connected client. +/// +public class CacheableResultClientServerTests(ITestOutputHelper testOutputHelper) + : ClientServerTestBase(testOutputHelper) +{ + protected override void ConfigureServices(ServiceCollection services, IMcpServerBuilder mcpServerBuilder) + { + mcpServerBuilder + .WithListToolsHandler((_, _) => new ValueTask(new ListToolsResult + { + Tools = [new Tool { Name = "echo" }], + TimeToLive = TimeSpan.FromMinutes(5), + CacheScope = CacheScope.Public, + })) + .WithReadResourceHandler((request, _) => new ValueTask(new ReadResourceResult + { + Contents = [new TextResourceContents { Uri = request.Params!.Uri!, Text = "hi" }], + TimeToLive = TimeSpan.FromSeconds(30), + CacheScope = CacheScope.Private, + })); + } + + [Fact] + public async Task ListTools_PropagatesCachingHints_ToClient() + { + await using var client = await CreateMcpClientForServer(); + + var result = await client.ListToolsAsync( + new ListToolsRequestParams(), + TestContext.Current.CancellationToken); + + Assert.Equal(TimeSpan.FromMinutes(5), result.TimeToLive); + Assert.Equal(CacheScope.Public, result.CacheScope); + } + + [Fact] + public async Task ReadResource_PropagatesCachingHints_ToClient() + { + await using var client = await CreateMcpClientForServer(); + + var result = await client.ReadResourceAsync( + "test://resource", + cancellationToken: TestContext.Current.CancellationToken); + + Assert.Equal(TimeSpan.FromSeconds(30), result.TimeToLive); + Assert.Equal(CacheScope.Private, result.CacheScope); + } +} diff --git a/tests/ModelContextProtocol.Tests/Protocol/CacheableResultTests.cs b/tests/ModelContextProtocol.Tests/Protocol/CacheableResultTests.cs new file mode 100644 index 000000000..aba38bfa0 --- /dev/null +++ b/tests/ModelContextProtocol.Tests/Protocol/CacheableResultTests.cs @@ -0,0 +1,292 @@ +using ModelContextProtocol.Protocol; +using System.Text.Json; +using System.Text.Json.Nodes; + +namespace ModelContextProtocol.Tests.Protocol; + +/// +/// Tests for the SEP-2549 caching hints (ttlMs and cacheScope) carried by +/// implementations: the results of tools/list, +/// prompts/list, resources/list, resources/templates/list, and +/// resources/read. +/// +public static class CacheableResultTests +{ + public static IEnumerable CacheableResultTypes() + { + yield return new object[] { typeof(ListToolsResult) }; + yield return new object[] { typeof(ListPromptsResult) }; + yield return new object[] { typeof(ListResourcesResult) }; + yield return new object[] { typeof(ListResourceTemplatesResult) }; + yield return new object[] { typeof(ReadResourceResult) }; + } + + [Theory] + [MemberData(nameof(CacheableResultTypes))] + public static void CacheableResult_SerializesTtlMsAsIntegerMilliseconds(Type type) + { + var result = (ICacheableResult)Activator.CreateInstance(type)!; + result.TimeToLive = TimeSpan.FromMilliseconds(300_000); + result.CacheScope = CacheScope.Public; + + string json = JsonSerializer.Serialize(result, type, McpJsonUtilities.DefaultOptions); + var node = JsonNode.Parse(json)!.AsObject(); + + Assert.True(node.ContainsKey("ttlMs")); + Assert.Equal(JsonValueKind.Number, node["ttlMs"]!.GetValueKind()); + Assert.Equal(300_000, node["ttlMs"]!.GetValue()); + Assert.Equal("public", node["cacheScope"]!.GetValue()); + + var deserialized = (ICacheableResult)JsonSerializer.Deserialize(json, type, McpJsonUtilities.DefaultOptions)!; + Assert.Equal(TimeSpan.FromMilliseconds(300_000), deserialized.TimeToLive); + Assert.Equal(CacheScope.Public, deserialized.CacheScope); + } + + [Theory] + [MemberData(nameof(CacheableResultTypes))] + public static void CacheableResult_PrivateScope_RoundTrips(Type type) + { + var result = (ICacheableResult)Activator.CreateInstance(type)!; + result.TimeToLive = TimeSpan.Zero; + result.CacheScope = CacheScope.Private; + + string json = JsonSerializer.Serialize(result, type, McpJsonUtilities.DefaultOptions); + var node = JsonNode.Parse(json)!.AsObject(); + + // A TTL of zero is meaningful (immediately stale) and must still be emitted. + Assert.True(node.ContainsKey("ttlMs")); + Assert.Equal(0, node["ttlMs"]!.GetValue()); + Assert.Equal("private", node["cacheScope"]!.GetValue()); + + var deserialized = (ICacheableResult)JsonSerializer.Deserialize(json, type, McpJsonUtilities.DefaultOptions)!; + Assert.Equal(TimeSpan.Zero, deserialized.TimeToLive); + Assert.Equal(CacheScope.Private, deserialized.CacheScope); + } + + [Theory] + [MemberData(nameof(CacheableResultTypes))] + public static void CacheableResult_OmitsCachingHints_WhenUnset(Type type) + { + object result = Activator.CreateInstance(type)!; + + string json = JsonSerializer.Serialize(result, type, McpJsonUtilities.DefaultOptions); + var node = JsonNode.Parse(json)!.AsObject(); + + // Backward compatibility: servers that do not set the hints must not emit them. + Assert.False(node.ContainsKey("ttlMs")); + Assert.False(node.ContainsKey("cacheScope")); + + var deserialized = (ICacheableResult)JsonSerializer.Deserialize(json, type, McpJsonUtilities.DefaultOptions)!; + Assert.Null(deserialized.TimeToLive); + Assert.Null(deserialized.CacheScope); + } + + [Theory] + [MemberData(nameof(CacheableResultTypes))] + public static void CacheableResult_DeserializesMissingHints_AsNull(Type type) + { + // A response from a server that predates SEP-2549 contains neither field. + string json = "{}"; + + var deserialized = (ICacheableResult)JsonSerializer.Deserialize(json, type, McpJsonUtilities.DefaultOptions)!; + Assert.Null(deserialized.TimeToLive); + Assert.Null(deserialized.CacheScope); + } + + [Theory] + [MemberData(nameof(CacheableResultTypes))] + public static void CacheableResult_DeserializesNegativeTtl(Type type) + { + // Per SEP-2549, a negative ttlMs is preserved on the DTO; callers SHOULD treat it as zero. + string json = "{\"ttlMs\":-5,\"cacheScope\":\"public\"}"; + + var deserialized = (ICacheableResult)JsonSerializer.Deserialize(json, type, McpJsonUtilities.DefaultOptions)!; + Assert.Equal(TimeSpan.FromMilliseconds(-5), deserialized.TimeToLive); + } + + [Theory] + [MemberData(nameof(CacheableResultTypes))] + public static void CacheableResult_DeserializesOversizedTtl_ClampsInsteadOfThrowing(Type type) + { + // A hostile or buggy server could return a ttlMs that is a valid JSON integer but exceeds the + // range representable by TimeSpan. Deserialization must not throw (which would break reading the + // entire list); the value is clamped to TimeSpan.MaxValue instead. + string json = "{\"ttlMs\":9999999999999999,\"cacheScope\":\"public\"}"; + + var deserialized = (ICacheableResult)JsonSerializer.Deserialize(json, type, McpJsonUtilities.DefaultOptions)!; + Assert.Equal(TimeSpan.MaxValue, deserialized.TimeToLive); + } + + [Theory] + [MemberData(nameof(CacheableResultTypes))] + public static void CacheableResult_DeserializesLargeNegativeTtl_ClampsToMinValue(Type type) + { + string json = "{\"ttlMs\":-9999999999999999}"; + + var deserialized = (ICacheableResult)JsonSerializer.Deserialize(json, type, McpJsonUtilities.DefaultOptions)!; + Assert.Equal(TimeSpan.MinValue, deserialized.TimeToLive); + } + + [Theory] + [MemberData(nameof(CacheableResultTypes))] + public static void CacheableResult_DeserializesMaxRepresentableTtl_DoesNotThrow(Type type) + { + // The largest whole-millisecond count that fits in a TimeSpan must round-trip without clamping. + long maxWholeMs = long.MaxValue / TimeSpan.TicksPerMillisecond; + string json = $"{{\"ttlMs\":{maxWholeMs}}}"; + + var deserialized = (ICacheableResult)JsonSerializer.Deserialize(json, type, McpJsonUtilities.DefaultOptions)!; + Assert.Equal(TimeSpan.FromTicks(maxWholeMs * TimeSpan.TicksPerMillisecond), deserialized.TimeToLive); + } + + [Theory] + [MemberData(nameof(CacheableResultTypes))] + public static void CacheableResult_DeserializesHugeFloatTtl_ClampsInsteadOfThrowing(Type type) + { + // A fractional/exponent ttlMs whose tick count overflows to +Infinity is clamped to MaxValue + // rather than throwing. (1e400 is beyond double range, so GetDouble() itself returns +Infinity.) + Assert.Equal( + TimeSpan.MaxValue, + DeserializeTtl(type, "{\"ttlMs\":1e400}")); + + // 1e308 is finite but overflows once scaled into tick-space. + Assert.Equal( + TimeSpan.MaxValue, + DeserializeTtl(type, "{\"ttlMs\":1e308}")); + } + + [Theory] + [MemberData(nameof(CacheableResultTypes))] + public static void CacheableResult_DeserializesNegativeInfinityFloatTtl_ClampsToMinValue(Type type) + { + // A large negative exponent ttlMs yields -Infinity from GetDouble(); it must clamp to MinValue, + // not silently become long.MinValue ticks via the cast. + Assert.Equal( + TimeSpan.MinValue, + DeserializeTtl(type, "{\"ttlMs\":-1e400}")); + } + + [Theory] + [MemberData(nameof(CacheableResultTypes))] + public static void CacheableResult_DeserializesUnknownCacheScope_AsNull(Type type) + { + // A future/unknown cacheScope string must not break deserialization of the entire result; it is + // tolerated and surfaced as null (equivalent to an absent field, which clients treat as public). + // Non-string tokens, including objects and arrays, must likewise be tolerated and fully consumed. + foreach (string scope in new[] { "\"shared\"", "\"\"", "123", "true", "null", "{}", "[]", "{\"a\":1}", "[1,2]" }) + { + string json = $"{{\"cacheScope\":{scope}}}"; + + var deserialized = (ICacheableResult)JsonSerializer.Deserialize(json, type, McpJsonUtilities.DefaultOptions)!; + Assert.Null(deserialized.CacheScope); + } + } + + [Theory] + [MemberData(nameof(CacheableResultTypes))] + public static void CacheableResult_DeserializesCacheScope_CaseInsensitively(Type type) + { + // Casing of the security-relevant "private" hint must be honored rather than silently dropped to + // null (which clients treat as public), so matching is case-insensitive on read. + foreach (string scope in new[] { "PUBLIC", "Public", "pUbLiC" }) + { + var result = (ICacheableResult)JsonSerializer.Deserialize($"{{\"cacheScope\":\"{scope}\"}}", type, McpJsonUtilities.DefaultOptions)!; + Assert.Equal(CacheScope.Public, result.CacheScope); + } + + foreach (string scope in new[] { "PRIVATE", "Private", "pRiVaTe" }) + { + var result = (ICacheableResult)JsonSerializer.Deserialize($"{{\"cacheScope\":\"{scope}\"}}", type, McpJsonUtilities.DefaultOptions)!; + Assert.Equal(CacheScope.Private, result.CacheScope); + } + } + + private static TimeSpan? DeserializeTtl(Type type, string json) => + ((ICacheableResult)JsonSerializer.Deserialize(json, type, McpJsonUtilities.DefaultOptions)!).TimeToLive; + + [Theory] + [MemberData(nameof(CacheableResultTypes))] + public static void CacheableResult_DeserializesFractionalTtl(Type type) + { + string json = "{\"ttlMs\":1.5}"; + + var deserialized = (ICacheableResult)JsonSerializer.Deserialize(json, type, McpJsonUtilities.DefaultOptions)!; + Assert.Equal(TimeSpan.FromTicks((long)(1.5 * TimeSpan.TicksPerMillisecond)), deserialized.TimeToLive); + } + + [Fact] + public static void CacheScope_SerializesAsLowercaseStrings() + { + Assert.Equal("\"public\"", JsonSerializer.Serialize(CacheScope.Public, McpJsonUtilities.DefaultOptions)); + Assert.Equal("\"private\"", JsonSerializer.Serialize(CacheScope.Private, McpJsonUtilities.DefaultOptions)); + Assert.Equal(CacheScope.Public, JsonSerializer.Deserialize("\"public\"", McpJsonUtilities.DefaultOptions)); + Assert.Equal(CacheScope.Private, JsonSerializer.Deserialize("\"private\"", McpJsonUtilities.DefaultOptions)); + } + + [Theory] + [MemberData(nameof(CacheableResultTypes))] + public static void CacheableResult_DeserializesTtlWithoutCacheScope(Type type) + { + // ttlMs present, cacheScope absent: the SEP says an absent scope defaults to "public", + // but the SDK only propagates the wire value, so the DTO reports null (caller applies default). + string json = "{\"ttlMs\":1000}"; + + var deserialized = (ICacheableResult)JsonSerializer.Deserialize(json, type, McpJsonUtilities.DefaultOptions)!; + Assert.Equal(TimeSpan.FromSeconds(1), deserialized.TimeToLive); + Assert.Null(deserialized.CacheScope); + } + + [Theory] + [MemberData(nameof(CacheableResultTypes))] + public static void CacheableResult_DeserializesCacheScopeWithoutTtl(Type type) + { + // cacheScope present, ttlMs absent: a server may classify cacheability without a freshness hint. + string json = "{\"cacheScope\":\"private\"}"; + + var deserialized = (ICacheableResult)JsonSerializer.Deserialize(json, type, McpJsonUtilities.DefaultOptions)!; + Assert.Null(deserialized.TimeToLive); + Assert.Equal(CacheScope.Private, deserialized.CacheScope); + } + + [Theory] + [MemberData(nameof(CacheableResultTypes))] + public static void CacheableResult_PaginatedPages_CarryIndependentCachingHints(Type type) + { + // SEP-2549: each paginated page independently carries its own ttlMs/cacheScope. + // Two result instances representing consecutive pages must round-trip distinct hints. + var page1 = (ICacheableResult)Activator.CreateInstance(type)!; + page1.TimeToLive = TimeSpan.FromMinutes(10); + page1.CacheScope = CacheScope.Public; + + var page2 = (ICacheableResult)Activator.CreateInstance(type)!; + page2.TimeToLive = TimeSpan.FromSeconds(5); + page2.CacheScope = CacheScope.Private; + + var rt1 = (ICacheableResult)JsonSerializer.Deserialize( + JsonSerializer.Serialize(page1, type, McpJsonUtilities.DefaultOptions), type, McpJsonUtilities.DefaultOptions)!; + var rt2 = (ICacheableResult)JsonSerializer.Deserialize( + JsonSerializer.Serialize(page2, type, McpJsonUtilities.DefaultOptions), type, McpJsonUtilities.DefaultOptions)!; + + Assert.Equal(TimeSpan.FromMinutes(10), rt1.TimeToLive); + Assert.Equal(CacheScope.Public, rt1.CacheScope); + Assert.Equal(TimeSpan.FromSeconds(5), rt2.TimeToLive); + Assert.Equal(CacheScope.Private, rt2.CacheScope); + } + + [Fact] + public static void CacheableResult_MaxValueTtl_WriteThenRead_IsStableAcrossRoundTrips() + { + // Writing TimeSpan.MaxValue truncates the sub-millisecond remainder to a whole-millisecond + // integer (922337203685477 ms), so the first round-trip is slightly less than MaxValue. + // Critically, once written this value is a fixed point: further round-trips do not drift. + var first = RoundTrip(new ListToolsResult { TimeToLive = TimeSpan.MaxValue }); + var second = RoundTrip(new ListToolsResult { TimeToLive = first.TimeToLive }); + + Assert.NotEqual(TimeSpan.MaxValue, first.TimeToLive); + Assert.Equal(first.TimeToLive, second.TimeToLive); + } + + private static ListToolsResult RoundTrip(ListToolsResult result) => + JsonSerializer.Deserialize( + JsonSerializer.Serialize(result, McpJsonUtilities.DefaultOptions), McpJsonUtilities.DefaultOptions)!; +} diff --git a/tests/ModelContextProtocol.Tests/Protocol/TimeSpanMillisecondsConverterSharedTests.cs b/tests/ModelContextProtocol.Tests/Protocol/TimeSpanMillisecondsConverterSharedTests.cs new file mode 100644 index 000000000..9cea4caa6 --- /dev/null +++ b/tests/ModelContextProtocol.Tests/Protocol/TimeSpanMillisecondsConverterSharedTests.cs @@ -0,0 +1,57 @@ +using ModelContextProtocol.Protocol; +using System.Text.Json; + +namespace ModelContextProtocol.Tests.Protocol; + +/// +/// Regression tests guarding the behavior that is +/// shared between SEP-2549 caching hints and 's ttl/pollInterval. +/// The converter's read path was hardened to clamp out-of-range values instead of throwing; these tests +/// ensure that change did not alter behavior for normal McpTask values and that the clamping also +/// protects McpTask deserialization from hostile/oversized inputs. +/// +public static class TimeSpanMillisecondsConverterSharedTests +{ + private const string TaskEnvelope = + "{{\"taskId\":\"t1\",\"status\":\"working\",\"createdAt\":\"2024-01-01T00:00:00Z\"," + + "\"lastUpdatedAt\":\"2024-01-01T00:00:00Z\",{0}}}"; + + [Fact] + public static void McpTask_NormalTtlAndPollInterval_RoundTripUnchanged() + { + string json = string.Format(TaskEnvelope, "\"ttl\":86400000,\"pollInterval\":1000"); + + var task = JsonSerializer.Deserialize(json, McpJsonUtilities.DefaultOptions)!; + + Assert.Equal(TimeSpan.FromDays(1), task.TimeToLive); + Assert.Equal(TimeSpan.FromSeconds(1), task.PollInterval); + + // Re-serialize and confirm the integer millisecond values are preserved exactly. + string reserialized = JsonSerializer.Serialize(task, McpJsonUtilities.DefaultOptions); + var rt = JsonSerializer.Deserialize(reserialized, McpJsonUtilities.DefaultOptions)!; + Assert.Equal(TimeSpan.FromDays(1), rt.TimeToLive); + Assert.Equal(TimeSpan.FromSeconds(1), rt.PollInterval); + } + + [Fact] + public static void McpTask_OversizedTtl_ClampsInsteadOfThrowing() + { + // The same hardening that protects cacheable results must also keep McpTask deserialization + // from throwing on an out-of-range ttl. + string json = string.Format(TaskEnvelope, "\"ttl\":9999999999999999"); + + var task = JsonSerializer.Deserialize(json, McpJsonUtilities.DefaultOptions)!; + + Assert.Equal(TimeSpan.MaxValue, task.TimeToLive); + } + + [Fact] + public static void McpTask_NegativeInfinityPollInterval_ClampsToMinValue() + { + string json = string.Format(TaskEnvelope, "\"pollInterval\":-1e400"); + + var task = JsonSerializer.Deserialize(json, McpJsonUtilities.DefaultOptions)!; + + Assert.Equal(TimeSpan.MinValue, task.PollInterval); + } +}