feat: Implement strict trace continuation

src/Sentry/BindableSentryOptions.cs

@@ -46,6 +46,8 @@ internal partial class BindableSentryOptions
     public double? TracesSampleRate { get; set; }
     public List<string>? TracePropagationTargets { get; set; }
     public bool? PropagateTraceparent { get; set; }
+    public bool? StrictTraceContinuation { get; set; }
+    public string? OrgId { get; set; }
     public double? ProfilesSampleRate { get; set; }
     public StackTraceMode? StackTraceMode { get; set; }
     public long? MaxAttachmentSize { get; set; }
@@ -99,6 +101,8 @@ public void ApplyTo(SentryOptions options)
         options.ProfilesSampleRate = ProfilesSampleRate ?? options.ProfilesSampleRate;
         options.TracePropagationTargets = TracePropagationTargets?.Select(s => new StringOrRegex(s)).ToList() ?? options.TracePropagationTargets;
         options.PropagateTraceparent = PropagateTraceparent ?? options.PropagateTraceparent;
+        options.StrictTraceContinuation = StrictTraceContinuation ?? options.StrictTraceContinuation;
+        options.OrgId = OrgId ?? options.OrgId;
         options.StackTraceMode = StackTraceMode ?? options.StackTraceMode;
         options.MaxAttachmentSize = MaxAttachmentSize ?? options.MaxAttachmentSize;
         options.DetectStartupTime = DetectStartupTime ?? options.DetectStartupTime;

src/Sentry/Dsn.cs

@@ -38,20 +38,28 @@ internal sealed class Dsn
     /// </summary>
     private Uri ApiBaseUri { get; }
 
+    /// <summary>
+    /// The organization ID parsed from the DSN host (e.g., <c>o1</c> in <c>o1.ingest.us.sentry.io</c> yields <c>"1"</c>).
+    /// Returns <c>null</c> if no org ID is present in the DSN.
+    /// </summary>
+    public string? OrgId { get; internal set; }
+
     private Dsn(
         string source,
         string projectId,
         string? path,
         string? secretKey,
         string publicKey,
-        Uri apiBaseUri)
+        Uri apiBaseUri,
+        string? orgId = null)
     {
         Source = source;
         ProjectId = projectId;
         Path = path;
         SecretKey = secretKey;
         PublicKey = publicKey;
         ApiBaseUri = apiBaseUri;
+        OrgId = orgId;
     }
 
     public Uri GetStoreEndpointUri() => new(ApiBaseUri, "store/");
@@ -95,6 +103,19 @@ public static Dsn Parse(string dsn)
             throw new ArgumentException("Invalid DSN: A Project Id is required.");
         }
 
+        // Parse org ID from host (e.g., "o1.ingest.us.sentry.io" -> "1")
+        string? orgId = null;
+        var hostParts = uri.DnsSafeHost.Split('.');
+        if (hostParts.Length > 0)
+        {
+            var firstPart = hostParts[0];
+            if (firstPart.Length >= 2 && firstPart[0] == 'o' &&
+                ulong.TryParse(firstPart.Substring(1), out _))
+            {
+                orgId = firstPart.Substring(1);
+            }
+        }
+
         var apiBaseUri = new UriBuilder
         {
             Scheme = uri.Scheme,
@@ -109,7 +130,8 @@ public static Dsn Parse(string dsn)
             path,
             secretKey,
             publicKey,
-            apiBaseUri);
+            apiBaseUri,
+            orgId);
     }
 
     public static Dsn? TryParse(string? dsn)

src/Sentry/DynamicSamplingContext.cs

@@ -29,7 +29,8 @@ private DynamicSamplingContext(SentryId traceId,
         string? release = null,
         string? environment = null,
         string? transactionName = null,
-        IReplaySession? replaySession = null)
+        IReplaySession? replaySession = null,
+        string? orgId = null)
     {
         // Validate and set required values
         if (traceId == SentryId.Empty)
@@ -94,6 +95,11 @@ private DynamicSamplingContext(SentryId traceId,
             items.Add("replay_id", replayId.ToString());
         }
 
+        if (!string.IsNullOrWhiteSpace(orgId))
+        {
+            items.Add("org_id", orgId);
+        }
+
         _items = items;
     }
 
@@ -199,7 +205,8 @@ public static DynamicSamplingContext CreateFromTransaction(TransactionTracer tra
             release,
             environment,
             transactionName,
-            replaySession);
+            replaySession,
+            orgId: options.GetEffectiveOrgId());
     }
 
     public static DynamicSamplingContext CreateFromUnsampledTransaction(UnsampledTransaction transaction, SentryOptions options, IReplaySession? replaySession)
@@ -224,7 +231,8 @@ public static DynamicSamplingContext CreateFromUnsampledTransaction(UnsampledTra
             release,
             environment,
             transactionName,
-            replaySession);
+            replaySession,
+            orgId: options.GetEffectiveOrgId());
     }
 
     public static DynamicSamplingContext CreateFromPropagationContext(SentryPropagationContext propagationContext, SentryOptions options, IReplaySession? replaySession)
@@ -240,7 +248,8 @@ public static DynamicSamplingContext CreateFromPropagationContext(SentryPropagat
             null,
             release: release,
             environment: environment,
-            replaySession: replaySession
+            replaySession: replaySession,
+            orgId: options.GetEffectiveOrgId()
             );
     }
 
@@ -263,7 +272,8 @@ public static DynamicSamplingContext CreateFromPropagationContext(SentryPropagat
             propagationContext.SampleRand,
             release: release,
             environment: environment,
-            replaySession: replaySession
+            replaySession: replaySession,
+            orgId: options.GetEffectiveOrgId()
             );
     }
 }

src/Sentry/Internal/Hub.cs

@@ -378,6 +378,13 @@ public TransactionContext ContinueTrace(
         string? name = null,
         string? operation = null)
     {
+        if (!ShouldContinueTrace(baggageHeader))
+        {
+            _options.LogDebug("Not continuing trace due to org ID validation. Starting new trace.");
+            traceHeader = null;
+            baggageHeader = null;
+        }
+
         var propagationContext = SentryPropagationContext.CreateFromHeaders(_options.DiagnosticLogger, traceHeader, baggageHeader, _replaySession);
         ConfigureScope(static (scope, propagationContext) => scope.SetPropagationContext(propagationContext), propagationContext);
 
@@ -391,6 +398,39 @@ public TransactionContext ContinueTrace(
             isParentSampled: traceHeader?.IsSampled);
     }
 
+    internal bool ShouldContinueTrace(BaggageHeader? baggageHeader)
+    {
+        var sdkOrgId = _options.GetEffectiveOrgId();
+
+        string? baggageOrgId = null;
+        if (baggageHeader is not null)
+        {
+            var sentryMembers = baggageHeader.GetSentryMembers();
+            sentryMembers.TryGetValue("org_id", out baggageOrgId);
+        }
+
+        // Mismatched org IDs always cause a new trace, regardless of strict mode
+        if (!string.IsNullOrEmpty(sdkOrgId) && !string.IsNullOrEmpty(baggageOrgId) && sdkOrgId != baggageOrgId)
+        {
+            return false;
+        }
+
+        // In strict mode, both must be present and match
+        if (_options.StrictTraceContinuation)
+        {
+            // If both are missing, continue (nothing to compare)
+            if (string.IsNullOrEmpty(sdkOrgId) && string.IsNullOrEmpty(baggageOrgId))
+            {
+                return true;
+            }
+
+            // Both must be present and equal
+            return sdkOrgId == baggageOrgId;
+        }
+
+        return true;
+    }
+
     public void StartSession()
     {
         // Attempt to recover persisted session left over from previous run

src/Sentry/SentryOptions.cs

@@ -452,6 +452,24 @@ public string? Dsn
     internal Dsn? _parsedDsn;
     internal Dsn ParsedDsn => _parsedDsn ??= Sentry.Dsn.Parse(Dsn!);
 
+    /// <summary>
+    /// Returns the effective org ID, preferring <see cref="OrgId"/> if set, otherwise falling back to the DSN-parsed value.
+    /// </summary>
+    internal string? GetEffectiveOrgId()
+    {
+        if (!string.IsNullOrWhiteSpace(OrgId))
+        {
+            return OrgId;
+        }
+
+        if (!string.IsNullOrWhiteSpace(Dsn))
+        {
+            return ParsedDsn.OrgId;
+        }
+
+        return null;
+    }
+
     private readonly Lazy<string> _sentryBaseUrl;
 
     internal bool IsSentryRequest(string? requestUri) =>
@@ -1068,6 +1086,28 @@ public IList<StringOrRegex> TracePropagationTargets
     /// <seealso href="https://develop.sentry.dev/sdk/telemetry/traces/#propagatetraceparent"/>
     public bool PropagateTraceparent { get; set; }
 
+    /// <summary>
+    /// Controls trace continuation from third-party services that happen to be instrumented by Sentry.
+    /// </summary>
+    /// <remarks>
+    /// When enabled, the SDK will require org IDs from baggage to match for continuing the trace.
+    /// If the incoming trace does not contain an org ID and this option is <c>true</c>, a new trace will be started.
+    /// When disabled (default), incoming traces without org IDs will be continued as normal,
+    /// but mismatched org IDs will always cause a new trace to be started regardless of this setting.
+    /// </remarks>
+    public bool StrictTraceContinuation { get; set; }
+
+    /// <summary>
+    /// Configures the org ID used for trace propagation and features like <see cref="StrictTraceContinuation"/>.
+    /// </summary>
+    /// <remarks>
+    /// In most cases the org ID is already parsed from the DSN (e.g., <c>o1</c> in
+    /// <c>https://key@o1.ingest.us.sentry.io/123</c> yields org ID <c>"1"</c>).
+    /// Use this option when non-standard Sentry DSNs are used, such as self-hosted or when using a local Relay.
+    /// When set, this value overrides the org ID parsed from the DSN.
+    /// </remarks>
+    public string? OrgId { get; set; }
+
     internal ITransactionProfilerFactory? TransactionProfilerFactory { get; set; }
 
     private StackTraceMode? _stackTraceMode;

test/Sentry.Testing/DsnSamples.cs

@@ -8,6 +8,11 @@ public static class DsnSamples
     /// </summary>
     public const string ValidDsn = "https://d4d82fc1c2c4032a83f3a29aa3a3aff@fake-sentry.io:65535/2147483647";
 
+    /// <summary>
+    /// A DSN whose host has an org-ID prefix (e.g. o123.ingest.us.sentry.io), causing OrgId to be parsed as "123".
+    /// </summary>
+    public const string ValidDsnWithOrgId = "https://d4d82fc1c2c4032a83f3a29aa3a3aff@o123.ingest.us.sentry.io/456";
+
     /// <summary>
     /// Missing ProjectId
     /// </summary>

test/Sentry.Tests/ApiApprovalTests.Run.DotNet10_0.verified.txt

@@ -825,6 +825,7 @@ namespace Sentry
         public int MaxCacheItems { get; set; }
         public int MaxQueueItems { get; set; }
         public Sentry.Extensibility.INetworkStatusListener? NetworkStatusListener { get; set; }
+        public string? OrgId { get; set; }
         public double? ProfilesSampleRate { get; set; }
         public bool PropagateTraceparent { get; set; }
         public string? Release { get; set; }
@@ -840,6 +841,7 @@ namespace Sentry
         public System.TimeSpan ShutdownTimeout { get; set; }
         public string SpotlightUrl { get; set; }
         public Sentry.StackTraceMode StackTraceMode { get; set; }
+        public bool StrictTraceContinuation { get; set; }
         public System.Collections.Generic.IList<Sentry.StringOrRegex> TagFilters { get; set; }
         public System.Collections.Generic.IList<Sentry.HttpStatusCodeRange> TraceIgnoreStatusCodes { get; set; }
         public System.Collections.Generic.IList<Sentry.StringOrRegex> TracePropagationTargets { get; set; }

test/Sentry.Tests/ApiApprovalTests.Run.DotNet8_0.verified.txt

@@ -825,6 +825,7 @@ namespace Sentry
         public int MaxCacheItems { get; set; }
         public int MaxQueueItems { get; set; }
         public Sentry.Extensibility.INetworkStatusListener? NetworkStatusListener { get; set; }
+        public string? OrgId { get; set; }
         public double? ProfilesSampleRate { get; set; }
         public bool PropagateTraceparent { get; set; }
         public string? Release { get; set; }
@@ -840,6 +841,7 @@ namespace Sentry
         public System.TimeSpan ShutdownTimeout { get; set; }
         public string SpotlightUrl { get; set; }
         public Sentry.StackTraceMode StackTraceMode { get; set; }
+        public bool StrictTraceContinuation { get; set; }
         public System.Collections.Generic.IList<Sentry.StringOrRegex> TagFilters { get; set; }
         public System.Collections.Generic.IList<Sentry.HttpStatusCodeRange> TraceIgnoreStatusCodes { get; set; }
         public System.Collections.Generic.IList<Sentry.StringOrRegex> TracePropagationTargets { get; set; }

test/Sentry.Tests/ApiApprovalTests.Run.DotNet9_0.verified.txt

@@ -825,6 +825,7 @@ namespace Sentry
         public int MaxCacheItems { get; set; }
         public int MaxQueueItems { get; set; }
         public Sentry.Extensibility.INetworkStatusListener? NetworkStatusListener { get; set; }
+        public string? OrgId { get; set; }
         public double? ProfilesSampleRate { get; set; }
         public bool PropagateTraceparent { get; set; }
         public string? Release { get; set; }
@@ -840,6 +841,7 @@ namespace Sentry
         public System.TimeSpan ShutdownTimeout { get; set; }
         public string SpotlightUrl { get; set; }
         public Sentry.StackTraceMode StackTraceMode { get; set; }
+        public bool StrictTraceContinuation { get; set; }
         public System.Collections.Generic.IList<Sentry.StringOrRegex> TagFilters { get; set; }
         public System.Collections.Generic.IList<Sentry.HttpStatusCodeRange> TraceIgnoreStatusCodes { get; set; }
         public System.Collections.Generic.IList<Sentry.StringOrRegex> TracePropagationTargets { get; set; }

test/Sentry.Tests/ApiApprovalTests.Run.Net4_8.verified.txt

@@ -812,6 +812,7 @@ namespace Sentry
         public int MaxCacheItems { get; set; }
         public int MaxQueueItems { get; set; }
         public Sentry.Extensibility.INetworkStatusListener? NetworkStatusListener { get; set; }
+        public string? OrgId { get; set; }
         public double? ProfilesSampleRate { get; set; }
         public bool PropagateTraceparent { get; set; }
         public string? Release { get; set; }
@@ -827,6 +828,7 @@ namespace Sentry
         public System.TimeSpan ShutdownTimeout { get; set; }
         public string SpotlightUrl { get; set; }
         public Sentry.StackTraceMode StackTraceMode { get; set; }
+        public bool StrictTraceContinuation { get; set; }
         public System.Collections.Generic.IList<Sentry.StringOrRegex> TagFilters { get; set; }
         public System.Collections.Generic.IList<Sentry.HttpStatusCodeRange> TraceIgnoreStatusCodes { get; set; }
         public System.Collections.Generic.IList<Sentry.StringOrRegex> TracePropagationTargets { get; set; }