feat: Tracing without performance

src/Sentry/BaggageHeader.cs

@@ -8,7 +8,7 @@ namespace Sentry;
 /// </summary>
 /// <seealso href="https://develop.sentry.dev/sdk/performance/dynamic-sampling-context"/>
 /// <seealso href="https://www.w3.org/TR/baggage"/>
-internal class BaggageHeader
+public class BaggageHeader
 {
     internal const string HttpHeaderName = "baggage";
     internal const string SentryKeyPrefix = "sentry-";
@@ -19,14 +19,14 @@ internal class BaggageHeader
     // "Uniqueness of keys between multiple list-members in a baggage-string is not guaranteed."
     // "The order of duplicate entries SHOULD be preserved when mutating the list."
 
-    public IReadOnlyList<KeyValuePair<string, string>> Members { get; }
+    internal IReadOnlyList<KeyValuePair<string, string>> Members { get; }
 
     private BaggageHeader(IEnumerable<KeyValuePair<string, string>> members) =>
         Members = members.ToList();
 
     // We can safely return a dictionary of Sentry members, as we are in control over the keys added.
     // Just to be safe though, we'll group by key and only take the first of each one.
-    public IReadOnlyDictionary<string, string> GetSentryMembers() =>
+    internal IReadOnlyDictionary<string, string> GetSentryMembers() =>
         Members
             .Where(kvp => kvp.Key.StartsWith(SentryKeyPrefix))
             .GroupBy(kvp => kvp.Key, kvp => kvp.Value)
@@ -107,7 +107,7 @@ public override string ToString()
         return members.Count == 0 ? null : new BaggageHeader(members);
     }
 
-    public static BaggageHeader Create(
+    internal static BaggageHeader Create(
         IEnumerable<KeyValuePair<string, string>> items,
         bool useSentryPrefix = false)
     {
@@ -121,7 +121,7 @@ public static BaggageHeader Create(
         return new BaggageHeader(members);
     }
 
-    public static BaggageHeader Merge(IEnumerable<BaggageHeader> baggageHeaders) =>
+    internal static BaggageHeader Merge(IEnumerable<BaggageHeader> baggageHeaders) =>
         new(baggageHeaders.SelectMany(x => x.Members));
 
     private static bool IsValidKey(string? key)

src/Sentry/Extensibility/DisabledHub.cs

@@ -74,6 +74,21 @@ public void BindException(Exception exception, ISpan span)
     /// </summary>
     public SentryTraceHeader? GetTraceHeader() => null;
 
+    /// <summary>
+    /// Returns null.
+    /// </summary>
+    public SentryTraceHeader? GetTraceParent() => null;
+
+    /// <summary>
+    /// Returns null.
+    /// </summary>
+    public BaggageHeader? GetBaggage() => null;
+
+    /// <summary>
+    /// Returns null.
+    /// </summary>
+    public TransactionContext? ContinueTrace(string? sentryTrace, string? baggageHeaders) => null;
+
     /// <summary>
     /// No-Op.
     /// </summary>

src/Sentry/Extensibility/HubAdapter.cs

@@ -96,6 +96,27 @@ public void BindException(Exception exception, ISpan span) =>
     public SentryTraceHeader? GetTraceHeader()
         => SentrySdk.GetTraceHeader();
 
+    /// <summary>
+    /// Forwards the call to <see cref="SentrySdk"/>.
+    /// </summary>
+    [DebuggerStepThrough]
+    public SentryTraceHeader? GetTraceParent()
+        => SentrySdk.GetTraceParent();
+
+    /// <summary>
+    /// Forwards the call to <see cref="SentrySdk"/>.
+    /// </summary>
+    [DebuggerStepThrough]
+    public BaggageHeader? GetBaggage()
+        => SentrySdk.GetBaggage();
+
+    /// <summary>
+    /// Forwards the call to <see cref="SentrySdk"/>.
+    /// </summary>
+    [DebuggerStepThrough]
+    public TransactionContext? ContinueTrace(string? sentryTrace, string? baggageHeaders)
+        => SentrySdk.ContinueTrace(sentryTrace, baggageHeaders);
+
     /// <summary>
     /// Forwards the call to <see cref="SentrySdk"/>.
     /// </summary>

src/Sentry/IHub.cs

@@ -44,6 +44,24 @@ ITransaction StartTransaction(
     /// </summary>
     SentryTraceHeader? GetTraceHeader();
 
+    /// <summary>
+    /// Gets the Sentry trace header of the parent that allows tracing across services
+    /// </summary>
+    SentryTraceHeader? GetTraceParent();
+
+    /// <summary>
+    /// Gets the Sentry "baggage" header that allows tracing across services
+    /// </summary>
+    BaggageHeader? GetBaggage();
+
+    /// <summary>
+    /// Continues a trace based on HTTP header values.
+    /// </summary>
+    /// /// <remarks>
+    /// If no "sentry-trace" header is provided a random trace ID and span ID is created.
+    /// </remarks>
+    TransactionContext? ContinueTrace(string? sentryTrace, string? baggageHeaders);
+
     /// <summary>
     /// Starts a new session.
     /// </summary>

src/Sentry/Internal/Hub.cs

@@ -195,7 +195,44 @@ public void BindException(Exception exception, ISpan span)
 
     public ISpan? GetSpan() => ScopeManager.GetCurrent().Key.Span;
 
-    public SentryTraceHeader? GetTraceHeader() => GetSpan()?.GetTraceHeader();
+    public SentryTraceHeader? GetTraceHeader() => GetTraceParent();
+
+    public SentryTraceHeader? GetTraceParent()
+    {
+        var traceHeader = GetSpan()?.GetTraceHeader();
+        if (traceHeader is not null)
+        {
+            return traceHeader;
+        }
+
+        var propagationContext = ScopeManager.GetCurrent().Key.PropagationContext;
+        if (propagationContext is not null)
+        {
+            return new SentryTraceHeader(propagationContext.TraceId, propagationContext.SpanId, null);
+        }
+
+        return null;
+    }
+
+    public BaggageHeader? GetBaggage()
+    {
+        throw new NotImplementedException();
+    }
+
+    public TransactionContext? ContinueTrace(string? sentryTrace, string? baggageHeaders)
+    {
+        var propagationContext = SentryPropagationContext.CreateFromHeaders(sentryTrace, baggageHeaders);
+        ConfigureScope(scope => scope.PropagationContext = propagationContext);
+
+        if (_options.IsTracingEnabled)
+        {
+            return new TransactionContext(propagationContext.SpanId,propagationContext.ParentSpanId, propagationContext.TraceId, "", "", "", null, null, null);
+        }
+        else
+        {
+            return null;
+        }
+    }
 
     public void StartSession()
     {

src/Sentry/Scope.cs

@@ -191,6 +191,8 @@ public ITransaction? Transaction
         set => _transaction = value;
     }
 
+    internal SentryPropagationContext? PropagationContext { get; set; }
+
     internal SessionUpdate? SessionUpdate { get; set; }
 
     /// <inheritdoc />

src/Sentry/SentryPropagationContext.cs

@@ -0,0 +1,45 @@
+namespace Sentry;
+
+internal class SentryPropagationContext
+{
+    public SentryId TraceId { get; }
+    public SpanId SpanId { get; }
+    public SpanId? ParentSpanId { get; }
+    public DynamicSamplingContext? DynamicSamplingContext { get; }
+
+    private SentryPropagationContext(
+        SentryTraceHeader traceHeader,
+        SpanId? parentSpanId,
+        DynamicSamplingContext? dynamicSamplingContext)
+    {
+        TraceId = traceHeader.TraceId;
+        SpanId = traceHeader.SpanId;
+        ParentSpanId = parentSpanId;
+        DynamicSamplingContext = dynamicSamplingContext;
+    }
+
+    private SentryPropagationContext()
+    {
+        TraceId = new SentryId();
+        SpanId = new SpanId();
+    }
+
+    public static SentryPropagationContext CreateFromHeaders(string? sentryTraceHeader, string? baggageHeadersString)
+    {
+        if (sentryTraceHeader == null)
+        {
+            return new SentryPropagationContext();
+        }
+
+        var traceHeader = SentryTraceHeader.Parse(sentryTraceHeader);
+
+        DynamicSamplingContext? dynamicSamplingContext = null;
+        if (baggageHeadersString is not null)
+        {
+            var baggageHeader = BaggageHeader.TryParse(baggageHeadersString);
+            dynamicSamplingContext = baggageHeader?.CreateDynamicSamplingContext();
+        }
+
+        return new SentryPropagationContext(traceHeader, null, dynamicSamplingContext);
+    }
+}

src/Sentry/SentrySdk.cs

@@ -614,9 +614,34 @@ public static void BindException(Exception exception, ISpan span)
     /// Gets the Sentry trace header.
     /// </summary>
     [DebuggerStepThrough]
+    // [Obsolete("This method will be removed in a future major version. Use the `GetTraceParent` instead.")]
     public static SentryTraceHeader? GetTraceHeader()
         => CurrentHub.GetTraceHeader();
 
+    /// <summary>
+    /// Gets the Sentry trace header of the parent that allows tracing across services
+    /// </summary>
+    [DebuggerStepThrough]
+    public static SentryTraceHeader? GetTraceParent()
+        => CurrentHub.GetTraceParent();
+
+    /// <summary>
+    /// Gets the Sentry "baggage" header that allows tracing across services
+    /// </summary>
+    [DebuggerStepThrough]
+    public static BaggageHeader? GetBaggage()
+        => CurrentHub.GetBaggage();
+
+    /// <summary>
+    /// Continues a trace based on HTTP header values.
+    /// </summary>
+    /// <remarks>
+    /// If no "sentry-trace" header is provided a random trace ID and span ID is created.
+    /// </remarks>
+    [DebuggerStepThrough]
+    public static TransactionContext? ContinueTrace(string? sentryTrace, string? baggageHeaders)
+        => CurrentHub.ContinueTrace(sentryTrace, baggageHeaders);
+
     /// <inheritdoc cref="IHub.StartSession"/>
     [DebuggerStepThrough]
     public static void StartSession()