io.gravitee.gateway.flow.policy.PolicyChainFactory Maven / Gradle / Ivy
/*
* Copyright © 2015 The Gravitee team (http://gravitee.io)
*
* 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 io.gravitee.gateway.flow.policy;
import io.gravitee.gateway.api.ExecutionContext;
import io.gravitee.gateway.api.buffer.Buffer;
import io.gravitee.gateway.core.processor.StreamableProcessor;
import io.gravitee.gateway.policy.NoOpPolicyChain;
import io.gravitee.gateway.policy.Policy;
import io.gravitee.gateway.policy.PolicyManager;
import io.gravitee.gateway.policy.PolicyMetadata;
import io.gravitee.gateway.policy.StreamType;
import io.gravitee.gateway.policy.impl.OrderedPolicyChain;
import io.gravitee.gateway.policy.impl.ReversedPolicyChain;
import java.util.List;
import java.util.Objects;
import java.util.function.Function;
import java.util.stream.Collectors;
/**
* A factory of {@link io.gravitee.policy.api.PolicyChain}.
*
* @author David BRASSELY (david.brassely at graviteesource.com)
* @author GraviteeSource Team
*/
public class PolicyChainFactory {
private final PolicyManager policyManager;
public PolicyChainFactory(final PolicyManager policyManager) {
this.policyManager = policyManager;
}
public StreamableProcessor create(
final List resolvedPolicies,
final StreamType streamType,
final ExecutionContext context
) {
return create(
resolvedPolicies,
streamType,
context,
policies ->
streamType == StreamType.ON_REQUEST
? OrderedPolicyChain.create(policies, context)
: ReversedPolicyChain.create(policies, context)
);
}
public StreamableProcessor create(
List resolvedPolicies,
StreamType streamType,
ExecutionContext context,
Function, StreamableProcessor> mapper
) {
if (resolvedPolicies.isEmpty()) {
return new NoOpPolicyChain(context);
}
final List policies = resolvedPolicies
.stream()
.map(policyMetadata -> policyManager.create(streamType, policyMetadata))
.filter(Objects::nonNull)
.collect(Collectors.toList());
return mapper.apply(policies);
}
}