com.github.enadim.spring.cloud.ribbon.propagator.AbstractExecutionContextCopy Maven / Gradle / Ivy
/*
* Copyright (c) 2017 the original author or 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 com.github.enadim.spring.cloud.ribbon.propagator;
import com.github.enadim.spring.cloud.ribbon.context.ExecutionContext;
import lombok.Getter;
import lombok.extern.slf4j.Slf4j;
import javax.validation.constraints.NotNull;
import java.util.ArrayList;
import java.util.List;
import java.util.Map;
import java.util.Map.Entry;
import java.util.Set;
import static com.github.enadim.spring.cloud.ribbon.context.ExecutionContextHolder.current;
/**
* Abstract {@link ExecutionContext} Copy to a target object.
* Defines {@link #copy(Object)} method that copies current {@link ExecutionContext} entries pre-filtering using the defined {@link #filter} and the defined copy function {@link #executionContextCopyFunction}.
*
* @param The target type of the copy.
* @author Nadim Benabdenbi
*/
@Slf4j
@Getter
public class AbstractExecutionContextCopy {
/**
* The context entry key filter.
*/
private final Filter filter;
/**
* The execution context copy function.
*/
private final ExecutionContextCopyFunction executionContextCopyFunction;
/**
* The extra static entries to copy.
*/
private final Map extraStaticEntries;
/**
* Sole Constructor.
*
* @param filter the context entry key filter
* @param executionContextCopyFunction the execution context copy function.
* @param extraStaticEntries The extra static entries to copy.
*/
public AbstractExecutionContextCopy(@NotNull Filter filter,
@NotNull ExecutionContextCopyFunction executionContextCopyFunction,
@NotNull Map extraStaticEntries) {
this.filter = filter;
this.executionContextCopyFunction = executionContextCopyFunction;
this.extraStaticEntries = extraStaticEntries;
}
/**
* Copies current {@link ExecutionContext} attributes keys that matches {@link #filter} using the {@link #executionContextCopyFunction}.
*
* @param t the target type of the copy.
* @return the copied {@link ExecutionContext} entries.
*/
protected List> copy(T t) {
List> result = new ArrayList<>();
copy(t, current().entrySet(), result);
copy(t, extraStaticEntries.entrySet(), result);
return result;
}
/**
* Copies the entry set that matches {@link #filter} using the {@link #executionContextCopyFunction}.
*
* @param t the target type of the copy.
* @param entrySet the entry set to copy
* @param result the copied entries
*/
private void copy(T t, Set> entrySet, List> result) {
entrySet.stream()
.filter(x -> filter.accept(x.getKey()))
.forEach(x -> {
try {
executionContextCopyFunction.copy(t, x.getKey(), x.getValue());
result.add(x);
} catch (Exception e) {
log.debug("Failed to copy {}.", x, e);
}
});
}
/**
* The function that copies the execution context attributes to a target object.
*
* @param the target type of the copy.
*/
@FunctionalInterface
public interface ExecutionContextCopyFunction {
/**
* Copies the execution context attributes to the target object.
*
* @param t the target.
* @param key the attribute key to copy.
* @param value the attribute value to copy.
* @throws Exception the checked sub class exception
*/
void copy(T t, String key, String value) throws Exception;
}
}