com.tangosol.internal.tracing.TracingHelper Maven / Gradle / Ivy
Show all versions of coherence Show documentation
/*
* Copyright (c) 2000, 2020, Oracle and/or its affiliates.
*
* Licensed under the Universal Permissive License v 1.0 as shown at
* http://oss.oracle.com/licenses/upl.
*/
package com.tangosol.internal.tracing;
import com.tangosol.net.CacheFactory;
import com.tangosol.net.Cluster;
import com.tangosol.net.Member;
import com.tangosol.util.Base;
import java.io.Serializable;
import java.util.HashMap;
import java.util.Objects;
import java.util.ServiceLoader;
/**
* Set of utility methods to work with the Coherence tracing abstraction.
*
* When this class is loaded, it will attempt to load the first {@link TracingShim} available on the classpath
* and delegate the API calls exposed here to the loaded {@link TracingShim shim}.
*
* @since 14.1.1.0
* @author rl 11.5.2019
*/
public final class TracingHelper
{
// ----- constructors ---------------------------------------------------
/**
* No instance necessary.
*/
private TracingHelper()
{
}
// ----- public methods -------------------------------------------------
/**
* Initialize the {@link Tracer}, if not already initialized.
*
* @param dependencies the tracing {@link TracingShim.Dependencies dependencies}
*
* @return a resource which can be used to terminate tracing, or {@code null} if it was already enabled
*/
public static TracingShim.Control initialize(TracingShim.Dependencies dependencies)
{
TracingShim tracingShim = m_tracingShim;
ClassLoader[] classLoaders = new ClassLoader[]
{
Base.getContextClassLoader(),
TracingShimLoader.class.getClassLoader()
};
loader:
for (int i = 0, len = classLoaders.length; i < len; i++)
{
ClassLoader loader = classLoaders[i];
try
{
ServiceLoader tracingShimLoaderService =
ServiceLoader.load(TracingShimLoader.class, loader);
for (TracingShimLoader tracingShimLoader : tracingShimLoaderService)
{
try
{
tracingShim = tracingShimLoader.loadTracingShim();
}
catch (Throwable t) // most likely a configuration issue with the tracing provider
{
if (CacheFactory.isLogEnabled(Base.LOG_ERR))
{
CacheFactory.log("Error invoking TracingShimLoader.loadTracingShim(). "
+ "Continuing to search for a valid tracing shim: " + t, Base.LOG_ERR);
CacheFactory.log(t);
}
continue;
}
if (isNoop(tracingShim))
{
continue;
}
m_tracingShim = tracingShim;
break loader; // first non-noop implementation wins
}
break; // break loader loop if no exception was thrown using the loop's classloader
}
catch (Throwable t) // exceptions here are from the ServiceLoader itself
{
if (CacheFactory.isLogEnabled(Base.LOG_WARN))
{
String msg = "Error loading tracing shim using the %s classloader: %s";
if (i == 0)
{
CacheFactory.log(String.format(msg, "context", t), Base.LOG_WARN);
CacheFactory.log("Attempting to load tracing shim using the fallback classloader.",
Base.LOG_WARN);
}
else
{
CacheFactory.log(String.format(msg, "fallback", t), Base.LOG_WARN);
CacheFactory.log("Tracing failed to initialize.", Base.LOG_WARN);
}
CacheFactory.log(t);
}
}
}
return tracingShim.initialize(dependencies);
}
/**
* Return {@code true} if the registered {@link Tracer} is effectively a no-op.
*
* @return {@code true} if the registered {@link Tracer} is effectively a no-op
*/
public static boolean isEnabled()
{
return m_tracingShim.isEnabled();
}
/**
* Return the {@link Tracer}.
*
* @return the current {@link Tracer}
*/
public static Tracer getTracer()
{
return m_tracingShim.getTracer();
}
/**
* Return the active {@link Span} if tracing is enabled and there is one active.
*
* @return the active {@link Span} or {@code null}
*/
public static Span getActiveSpan()
{
return isEnabled() ? getTracer().getCurrentSpan() : null;
}
/**
* Return the active {@link Span} if any, otherwise return a {@link Span} that is effectively a no-op.
*
* @return the active {@link Span} if any, otherwise return a {@link Span} that is effectively a no-op
*/
@SuppressWarnings("unused")
public static Span augmentSpan()
{
Span span = getActiveSpan();
return span == null ? m_tracingShim.getNoopSpan() : span;
}
/**
* Augments the specified {@link Span} with details related to the provided {@link Throwable}.
*
* @param span the {@link Span} to augment
* @param fIsError {@code true} if this span should be marked as erroneous
* @param t the {@link Throwable} to log
*
* @return the specified {@link Span}
*/
public static Span augmentSpanWithErrorDetails(Span span, boolean fIsError, Throwable t)
{
if (!isNoop(span))
{
if (fIsError)
{
span.setMetadata("error", true);
}
span.log(new HashMap(5)
{{
put("event", "error");
put("error.object", t);
}});
}
return span;
}
/**
* Return a {@link Span.Builder} for the specified operation.
*
* @param sOpName the operation name
*
* @return the {@link Span.Builder}
*/
public static Span.Builder newSpan(String sOpName)
{
if (isEnabled())
{
Span.Builder builder = getTracer().spanBuilder(sOpName)
.withMetadata("thread", Thread.currentThread().getName());
try
{
Cluster cluster = CacheFactory.getCluster();
Member member = cluster.isRunning() ? cluster.getLocalMember() : null;
if (member != null)
{
builder = builder.withMetadata("member", member.getId());
}
}
catch (Exception ignored)
{
} // getLocalMember can throw IllegalStateException
return Float.compare(0.0f, m_tracingShim.getDependencies().getSamplingRatio()) == 0
? new ConditionalSpanBuilder(builder)
: builder;
}
else
{
return m_tracingShim.getNoopSpanBuilder();
}
}
/**
* Return a {@link Span.Builder} for the specified stage and operation.
*
* @param sStage the stage of the operation
* @param op the operation
*
* @return the {@link Span.Builder builder}
*/
@SuppressWarnings("unused")
public static Span.Builder newSpan(String sStage, Object op)
{
if (isEnabled())
{
String sOpClass = null;
String sOpName;
if (op == null)
{
sOpName = sStage;
}
else
{
Class clz = op.getClass();
sOpClass = clz.getName();
// strip off package names, and $Poll suffix
sOpName = sOpClass;
int ofDot = sOpName.lastIndexOf('.') + 1;
sOpName = sOpName.endsWith("$Poll")
? sOpName.substring(ofDot, sOpName.length() - 5)
: sOpName.substring(ofDot);
// strip off any parent class, and any Request suffix
int ofDol = sOpName.lastIndexOf('$') + 1;
sOpName = sOpName.endsWith("Request")
? sOpName.substring(ofDol, sOpName.length() - 7)
: sOpName.substring(ofDol);
if (sStage != null)
{
sOpName += ('.' + sStage);
}
}
Span.Builder builder = newSpan(sOpName);
if (sOpClass != null)
{
builder = builder.withMetadata("operation.class", sOpClass);
}
builder = builder.withMetadata("span.kind",
sStage == null || !sStage.equals("request")
? "server"
: "client");
return builder;
}
else
{
return newSpan("no-op");
}
}
/**
* Returns {@code true} if the {@link NoopAware target} is {@code null} otherwise the result of calling
* {@link NoopAware#isNoop()}.
*
* @param target the {@link NoopAware} to query
*
* @return {@code true} if the {@link NoopAware target} is {@code null} otherwise the result of calling
* {@link NoopAware#isNoop()}
*/
public static boolean isNoop(NoopAware target)
{
return target == null || target.isNoop();
}
// ---- inner class: ConditionalSpanBuilder -------------------------------
/**
* A {@link Span.Builder} which conditionally builds a real {@link Span}.
*/
protected static class ConditionalSpanBuilder
implements Span.Builder
{
// ----- constructors -----------------------------------------------
/**
* Wraps an existing {@link Span.Builder} to enable conditional creation of Spans.
*
* @param delegate the {@link Span.Builder} to delegate calls to as appropriate
*
* @throws NullPointerException if {@code delegate} is {@code null}
*/
protected ConditionalSpanBuilder(Span.Builder delegate)
{
Objects.requireNonNull(delegate, "Parameter delegate cannot be null");
m_delegate = delegate;
}
// ----- Span.Builder interface -------------------------------------
@Override
public Span.Builder setParent(Span parent)
{
if (!TracingHelper.isNoop(parent))
{
m_delegate = m_delegate.setParent(parent);
}
return this;
}
@Override
public Span.Builder setParent(SpanContext remoteParent)
{
if (!TracingHelper.isNoop(remoteParent))
{
m_delegate = m_delegate.setParent(remoteParent);
}
return this;
}
@Override
public Span.Builder setNoParent()
{
m_fIgnoreActiveSpan = true;
m_delegate = m_delegate.setNoParent();
return this;
}
@Override
public Span.Builder withMetadata(String sKey, String sValue)
{
m_delegate = m_delegate.withMetadata(sKey, sValue);
return this;
}
@Override
public Span.Builder withMetadata(String sKey, boolean fValue)
{
m_delegate = m_delegate.withMetadata(sKey, fValue);
return this;
}
@Override
public Span.Builder withMetadata(String sKey, long lValue)
{
m_delegate = m_delegate.withMetadata(sKey, lValue);
return this;
}
@Override
public Span.Builder withMetadata(String sKey, double dValue)
{
m_delegate = m_delegate.withMetadata(sKey, dValue);
return this;
}
@Override
public Span.Builder withAssociation(String sLabel, SpanContext associatedContext)
{
m_delegate = m_delegate.withAssociation(sLabel, associatedContext);
return this;
}
@Override
public Span.Builder setStartTimestamp(long ldtStartTime)
{
m_delegate = m_delegate.setStartTimestamp(ldtStartTime);
return this;
}
@Override
public Span startSpan()
{
return dropSpan()
? TracingHelper.m_tracingShim.getNoopSpan()
: m_delegate.startSpan();
}
// ----- helper methods ---------------------------------------------
/**
* Return {@code true} if the {@link Span span} should not be created.
*
* @return {@code true} if the {@link Span span} should not be created.
*/
protected boolean dropSpan()
{
return m_fIgnoreActiveSpan || isNoop(getActiveSpan());
}
// ----- object methods ---------------------------------------------
@Override
public boolean equals(Object o)
{
if (this == o)
{
return true;
}
if (!(o instanceof ConditionalSpanBuilder))
{
return false;
}
ConditionalSpanBuilder that = (ConditionalSpanBuilder) o;
return m_fIgnoreActiveSpan == that.m_fIgnoreActiveSpan
&& Base.equals(m_delegate, that.m_delegate);
}
@Override
public int hashCode()
{
return Objects.hash(m_delegate, m_fIgnoreActiveSpan);
}
@Override
public String toString()
{
return "ConditionalSpanBuilder("
+ "DelegateBuilder=" + m_delegate
+ ", IgnoreActiveSpan=" + m_fIgnoreActiveSpan
+ ')';
}
// ----- data members -----------------------------------------------
/**
* The delegate {@link Span.Builder}.
*/
protected Span.Builder m_delegate;
/**
* Flag indicating if {@link #setNoParent()} ()} has been called.
*/
protected boolean m_fIgnoreActiveSpan;
}
// ----- data members ---------------------------------------------------
/**
* Singleton no-op {@link TracingShim} instance.
*/
protected static TracingShim m_tracingShim = TracingShim.Noop.INSTANCE;
}