Package io.honeycomb.beeline.tracing.propagation

Class HttpHeaderV1PropagationCodec

java.lang.Object

io.honeycomb.beeline.tracing.propagation.HttpHeaderV1PropagationCodec

All Implemented Interfaces:

PropagationCodec<String>

public class HttpHeaderV1PropagationCodec
extends Object
implements PropagationCodec<String>

Codec that can decode/encode trace context based on Version 1 of the honeycomb http header ('x-honeycomb-trace'). Prefer the Propagation.honeycombHeaderV1() factory method to retrieve an instance.

The design of this class avoids throwing exceptions in favour of logging warnings and returning null on encode or an "empty context" on decode.

Thread-safety

Instances of this class are thread-safe and can be shared.

Nested Class Summary

Nested Classes

Modifier and Type	Class	Description
static class	HttpHeaderV1PropagationCodec.DefaultJsonConverter

Field Summary

Fields

Modifier and Type	Field	Description
static String	HONEYCOMB_TRACE_HEADER

Constructor Summary

Constructors

Constructor	Description
HttpHeaderV1PropagationCodec()
HttpHeaderV1PropagationCodec(io.honeycomb.libhoney.transport.json.JsonSerializer<? super Map<String,?>> serializer, JsonDeserializer<? extends Map<String,Object>> deserializer)

Method Summary

Modifier and Type	Method	Description
PropagationContext	decode(String encodedTrace)	This decodes the 'x-honeycomb-trace' header of the following format:
Optional<String>	encode(PropagationContext context)	This encodes the given trace context in the format accepted by the 'x-honeycomb-trace' header.
static HttpHeaderV1PropagationCodec	getInstance()

Methods inherited from class java.lang.Object

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

Field Detail

HONEYCOMB_TRACE_HEADER

public static final String HONEYCOMB_TRACE_HEADER

See Also:

Constant Field Values

Constructor Detail

HttpHeaderV1PropagationCodec

public HttpHeaderV1PropagationCodec(io.honeycomb.libhoney.transport.json.JsonSerializer<? super Map<String,?>> serializer,
                                    JsonDeserializer<? extends Map<String,Object>> deserializer)

HttpHeaderV1PropagationCodec

public HttpHeaderV1PropagationCodec()

Method Detail

getInstance

public static HttpHeaderV1PropagationCodec getInstance()

decode

public PropagationContext decode(String encodedTrace)

This decodes the 'x-honeycomb-trace' header of the following format:

1;trace_id={traceId},parent_id={parentId},dataset={dataset},context={Base64-encoded json}

Trace_id and parent_id are required to create a non-empty Propagation context, while dataset and context are treated as optional.

Specified by:

decode in interface PropagationCodec<String>

Parameters:

encodedTrace - to decode into a PropagationContext.

Returns:

extracted context - "empty" context if encodedTrace value has an invalid format or is null.

encode

public Optional<String> encode(PropagationContext context)

This encodes the given trace context in the format accepted by the 'x-honeycomb-trace' header. This will return null if the span id or trace id are not set (i.e. the context is not an active trace).

Specified by:

encode in interface PropagationCodec<String>

Parameters:

context - to encode into a valid header value.

Returns:

a valid honeycomb trace header value - empty if required IDs are missing or input is null.