Package brave.baggage

Class BaggageFields

java.lang.Object

brave.baggage.BaggageFields

public final class BaggageFields
extends Object

This contains pre-defined fields, such as TRACE_ID and a way to create a constant field.

Built-in fields

The following are fields that dispatch to methods on the TraceContext. They are available regardless of BaggagePropagation. None will return in lookups such as BaggageField.getAll(TraceContext) or BaggageField.getByName(TraceContext, String)

1. TRACE_ID
2. PARENT_ID
3. SPAN_ID
4. SAMPLED

Since:

5.11

Field Summary

Fields

Modifier and Type	Field	Description
static BaggageField	PARENT_ID	Typically only useful when spans are parsed from log records.
static BaggageField	SAMPLED	This is only useful when TRACE_ID is also a baggage field.
static BaggageField	SPAN_ID	Used with TRACE_ID to correlate a log line with a span.
static BaggageField	TRACE_ID	This is the most common log correlation field.

Constructor Summary

Constructors

Constructor	Description
BaggageFields()

Method Summary

Modifier and Type	Method	Description
static BaggageField	constant(String name, String value)	Creates a local baggage field based on a possibly null constant, such as an ENV variable.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Details

TRACE_ID

public static final BaggageField TRACE_ID

This is the most common log correlation field.

Since:

5.11

See Also:

TraceContext.traceIdString()

PARENT_ID

public static final BaggageField PARENT_ID

Typically only useful when spans are parsed from log records.

Since:

5.11

See Also:

TraceContext.parentIdString()

SPAN_ID

public static final BaggageField SPAN_ID

Used with TRACE_ID to correlate a log line with a span.

Since:

5.11

See Also:

TraceContext.spanIdString()

SAMPLED

public static final BaggageField SAMPLED

This is only useful when TRACE_ID is also a baggage field. It is a hint that a trace may exist in Zipkin, when a user is viewing logs. For example, unsampled traces are not typically reported to Zipkin.

Since:

5.11

See Also:

SamplingFlags.sampled()

Constructor Details

BaggageFields

public BaggageFields()

Method Details

constant

public static BaggageField constant(String name, @Nullable String value)

Creates a local baggage field based on a possibly null constant, such as an ENV variable.

Ex.

 CLOUD_REGION = BaggageFields.constant("region", System.getEnv("CLOUD_REGION"));
 

Since:

5.11