Elastic APM OpenTracing bridge
editElastic APM OpenTracing bridge
editThe Elastic APM OpenTracing bridge makes allows to create Elastic APM Transactions
and Spans
,
using the OpenTracing API.
In other words,
it translates the calls to the OpenTracing API to Elastic APM and thus allows for reusing existing instrumentation.
The first span of a service will be converted to an Elastic APM
Transaction
,
subsequent spans are mapped to Elastic APM
Span
s.
Operation Modes
editThis bridge allows for different operation modes in combination with the Elastic APM javaagent
-
Noop
If thejavaagent
is not specified, the bridge is in noop mode and does not actually record and report spans. -
Mix and Match
If you want to leverage the auto instrumentation of Elastic APM, but also want do create custom spans or use the OpenTracing API to add custom tags to the spans created by Elastic APM, you can just do that. The OpenTracing bridge and the standard Elastic APM API interact seamlessly. -
Manual instrumentation
If you don’t want Elastic APM to auto-instrument known frameworks, but instead only rely on manual instrumentation, disable the auto instrumentation setting the configuration optioninstrument
tofalse
.
Getting started
editThe first step in getting started with the OpenTracing API bridge ist to declare a dependency to the API:
pom.xml.
<dependency> <groupId>co.elastic.apm</groupId> <artifactId>apm-opentracing</artifactId> <version>${elastic-apm.version}</version> </dependency>
build.gradle.
compile "co.elastic.apm:apm-opentracing:$elasticApmVersion"
Replace the version placeholders with the latest version from maven central:
Initialize tracer
editimport co.elastic.apm.opentracing.ElasticApmTracer; import io.opentracing.Tracer Tracer tracer = new ElasticApmTracer();
Elastic APM specific tags
editElastic APM defines some tags which are not included in the OpenTracing API but are relevant in the context of Elastic APM.
-
type
- sets the type of the transaction, for examplerequest
,ext
ordb
-
user.id
- sets the user id, appears in the "User" tab in the transaction details in the Elastic APM UI -
user.email
- sets the user email, appears in the "User" tab in the transaction details in the Elastic APM UI -
user.username
- sets the user name, appears in the "User" tab in the transaction details in the Elastic APM UI -
result
- sets the result of the transaction. Overrides the default value ofsuccess
. If theerror
tag is set totrue
, the default value iserror
.
Caveats
editNot all features of the OpenTracing API are supported.
Context propagation
editThis bridge only supports the formats Format.Builtin.TEXT_MAP
and Format.Builtin.HTTP_HEADERS
.
Format.Builtin.BINARY
is currently not supported.
Span References
editCurrently, this bridge only supports child_of
references.
Other references,
like follows_from
are not supported yet.
Baggage
editThe Span.setBaggageItem(String, String)
method is not supported.
Baggage items are silently dropped.
Logs
editOnly exception logging is supported.
Logging an Exception on the OpenTracing span will create an Elastic APM
Error
.
Example:
Exception e = ... span.log( Map.of( "event", "error", "error.object", e ) )