org.springframework.cloud.sleuth.annotation

Annotation Type SpanTag

@Retention(value=RUNTIME)
 @Inherited
 @Target(value=PARAMETER)
public @interface SpanTag

There are 3 different ways to add tags to a span. All of them are controlled by the annotation values. Precedence is:

• try with the TagValueResolver bean
• if the value of the bean wasn't set, try to evaluate a SPEL expression
• if there’s no SPEL expression just return a toString() value of the parameter

Since:

1.2.0

Author:

Christian Schwerdtfeger

Optional Element Summary

Optional Elements

Modifier and Type	Optional Element and Description
String	expression Execute this SPEL expression to calculate the tag value.
String	key The name of the key of the tag which should be created.
Class<? extends TagValueResolver>	resolver Use this bean to resolve the tag value.
String	value The name of the key of the tag which should be created.

Element Detail

value

@AliasFor(value="key")
public abstract String value

The name of the key of the tag which should be created.

Default:

""

key

@AliasFor(value="value")
public abstract String key

The name of the key of the tag which should be created.

Default:

""

expression

public abstract String expression

Execute this SPEL expression to calculate the tag value. Will be analyzed if no value of the resolver() was set.

Default:

""

resolver

public abstract Class<? extends TagValueResolver> resolver

Use this bean to resolve the tag value. Has the highest precedence.

Default:

org.springframework.cloud.sleuth.annotation.NoOpTagValueResolver.class