com.google.gerrit.server.plugincontext.PluginMapEntryContext Maven / Gradle / Ivy
// Copyright (C) 2018 The Android Open Source Project
//
// 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 com.google.gerrit.server.plugincontext;
import static java.util.Objects.requireNonNull;
import com.google.gerrit.extensions.registration.DynamicMap;
import com.google.gerrit.extensions.registration.Extension;
import com.google.gerrit.server.plugincontext.PluginContext.CheckedExtensionFunction;
import com.google.gerrit.server.plugincontext.PluginContext.ExtensionConsumer;
import com.google.gerrit.server.plugincontext.PluginContext.ExtensionFunction;
import com.google.gerrit.server.plugincontext.PluginContext.PluginMetrics;
/**
* Context to invoke an extension from {@link DynamicMap}.
*
* When the plugin extension is invoked a logging tag with the plugin name is set. This way any
* errors that are triggered by the plugin extension (even if they happen in Gerrit code which is
* called by the plugin extension) can be easily attributed to the plugin.
*
*
The run* methods execute the extension but don't deliver a result back to the caller.
* Exceptions can be caught and logged.
*
*
The call* methods execute the extension and deliver a result back to the caller.
*
*
* Map results = new HashMap<>();
* fooPluginMapEntryContext.run(
* extension -> results.put(extension.getExportName(), extension.get().getFoo());
*
*
* Example if all exceptions, but one, should be caught and logged:
*
*
* Map results = new HashMap<>();
* try {
* fooPluginMapEntryContext.run(
* extension -> results.put(extension.getExportName(), extension.get().getFoo(),
* MyException.class);
* } catch (MyException e) {
* // handle the exception
* }
*
*
* Example if return values should be handled:
*
*
* Object result = fooPluginMapEntryContext.call(extension -> extension.get().getFoo());
*
*
* Example if return values and a single exception should be handled:
*
*
* Object result;
* try {
* result = fooPluginMapEntryContext.call(extension -> extension.get().getFoo(), MyException.class);
* } catch (MyException e) {
* // handle the exception
* }
*
*
* Example if several exceptions should be handled:
*
*
* for (Extension fooExtension : fooDynamicMap) {
* try (TraceContext traceContext = PluginContext.newTrace(fooExtension)) {
* fooExtension.get().doFoo();
* } catch (MyException1 | MyException2 | MyException3 e) {
* // handle the exception
* }
* }
*
*/
public class PluginMapEntryContext {
private final Extension extension;
private final PluginMetrics pluginMetrics;
PluginMapEntryContext(Extension extension, PluginMetrics pluginMetrics) {
requireNonNull(extension);
requireNonNull(extension.getExportName(), "export name must be set for plugin map entries");
this.extension = extension;
this.pluginMetrics = pluginMetrics;
}
/**
* Returns the name of the plugin that registered this map entry.
*
* @return the plugin name
*/
public String getPluginName() {
return extension.getPluginName();
}
/**
* Returns the export name for which this map entry was registered.
*
* @return the export name
*/
public String getExportName() {
return extension.getExportName();
}
/**
* Invokes the plugin extension. All exceptions from the plugin extension are caught and logged.
*
* The consumer get the {@link Extension} provided that should be invoked. The extension
* provides access to the plugin name and the export name.
*
* @param extensionConsumer consumer that invokes the extension
*/
public void run(ExtensionConsumer> extensionConsumer) {
PluginContext.runLogExceptions(pluginMetrics, extension, extensionConsumer);
}
/**
* Invokes the plugin extension. All exceptions from the plugin extension are caught and logged.
*
* The consumer get the {@link Extension} provided that should be invoked. The extension
* provides access to the plugin name and the export name.
*
* @param extensionConsumer consumer that invokes the extension
* @param exceptionClass type of the exceptions that should be thrown
* @throws X expected exception from the plugin extension
*/
public void run(
ExtensionConsumer> extensionConsumer, Class exceptionClass) throws X {
PluginContext.runLogExceptions(pluginMetrics, extension, extensionConsumer, exceptionClass);
}
/**
* Calls the plugin extension and returns the result from the plugin extension call.
*
* The consumer get the {@link Extension} provided that should be invoked. The extension
* provides access to the plugin name and the export name.
*
* @param extensionFunction function that invokes the extension
* @return the result from the plugin extension
*/
public R call(ExtensionFunction, R> extensionFunction) {
return PluginContext.call(pluginMetrics, extension, extensionFunction);
}
/**
* Calls the plugin extension and returns the result from the plugin extension call. Exceptions of
* the specified type are thrown and must be handled by the caller.
*
* The consumer get the {@link Extension} provided that should be invoked. The extension
* provides access to the plugin name and the export name.
*
* @param checkedExtensionFunction function that invokes the extension
* @param exceptionClass type of the exceptions that should be thrown
* @return the result from the plugin extension
* @throws X expected exception from the plugin extension
*/
public R call(
CheckedExtensionFunction, R, X> checkedExtensionFunction,
Class exceptionClass)
throws X {
return PluginContext.call(pluginMetrics, extension, checkedExtensionFunction, exceptionClass);
}
}