zipkin.server.ConditionalOnSelfTracing Maven / Gradle / Ivy
/**
* Copyright 2015-2016 The OpenZipkin Authors
*
* Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file except
* in compliance with the License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software distributed under the License
* is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express
* or implied. See the License for the specific language governing permissions and limitations under
* the License.
*/
package zipkin.server;
import java.lang.annotation.ElementType;
import java.lang.annotation.Retention;
import java.lang.annotation.RetentionPolicy;
import java.lang.annotation.Target;
import org.springframework.boot.autoconfigure.condition.ConditionOutcome;
import org.springframework.boot.autoconfigure.condition.SpringBootCondition;
import org.springframework.context.annotation.ConditionContext;
import org.springframework.context.annotation.Conditional;
import org.springframework.core.annotation.AnnotationAttributes;
import org.springframework.core.type.AnnotatedTypeMetadata;
/**
* This helps solve a number of problems including the following, which sometimes only break in an
* alpine JRE. The solution is to go with pure properties instead.
*
*
* ConditionalOnClass(name = "com.github.kristofa.brave.Brave")
*
ConditionalOnBean(Brave.class)
*
*/
@Conditional(ConditionalOnSelfTracing.SelfTracingCondition.class)
@Retention(RetentionPolicy.RUNTIME)
@Target({ElementType.TYPE, ElementType.METHOD})
public @interface ConditionalOnSelfTracing {
String storageType() default "";
class SelfTracingCondition extends SpringBootCondition {
static final boolean BRAVE_PRESENT = checkForBrave();
static boolean checkForBrave() {
try {
Class.forName("com.github.kristofa.brave.Brave");
return true;
} catch (ClassNotFoundException e) {
return false;
}
}
@Override
public ConditionOutcome getMatchOutcome(ConditionContext context, AnnotatedTypeMetadata a) {
if (!BRAVE_PRESENT) {
return ConditionOutcome.noMatch("Brave must be in the classpath");
}
String selfTracingEnabled = context.getEnvironment()
.getProperty("zipkin.self-tracing.enabled");
if (!Boolean.valueOf(selfTracingEnabled)) {
return ConditionOutcome.noMatch("zipkin.self-tracing.enabled isn't true");
}
String expectedStorageType = AnnotationAttributes.fromMap(
a.getAnnotationAttributes(ConditionalOnSelfTracing.class.getName())
).getString("storageType");
if (expectedStorageType.equals("")) {
return ConditionOutcome.match();
}
String storageType = context.getEnvironment().getProperty("zipkin.storage.type");
return expectedStorageType.equals(storageType) ?
ConditionOutcome.match() :
ConditionOutcome.noMatch(
"zipkin.storage.type was: " + storageType + " expected " + expectedStorageType);
}
}
}