software.amazon.awssdk.services.signer.endpoints.internal.PartitionFn Maven / Gradle / Ivy

Show more of this group Show more artifacts with this name
Show all versions of signer Show documentation
The AWS Java SDK for Signer module holds the client classes that are used for communicating with Signer.
There is a newer version: 2.28.4
/*
 * Copyright Amazon.com, Inc. or its affiliates. All Rights Reserved.
 * 
 * Licensed under the Apache License, Version 2.0 (the "License"). You may not use this file except in compliance with
 * the License. A copy of the License is located at
 * 
 * http://aws.amazon.com/apache2.0
 * 
 * or in the "license" file accompanying this file. This file 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 software.amazon.awssdk.services.signer.endpoints.internal;

import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;
import java.util.Map;
import java.util.function.Supplier;
import java.util.regex.Pattern;
import software.amazon.awssdk.annotations.SdkInternalApi;
import software.amazon.awssdk.utils.MapUtils;

@SdkInternalApi
public class PartitionFn extends SingleArgFn {
    public static final String ID = "aws.partition";

    public static final Identifier NAME = Identifier.of("name");
    public static final Identifier DNS_SUFFIX = Identifier.of("dnsSuffix");
    public static final Identifier DUAL_STACK_DNS_SUFFIX = Identifier.of("dualStackDnsSuffix");
    public static final Identifier SUPPORTS_FIPS = Identifier.of("supportsFIPS");
    public static final Identifier SUPPORTS_DUAL_STACK = Identifier.of("supportsDualStack");
    public static final Identifier IMPLICIT_GLOBAL_REGION = Identifier.of("implicitGlobalRegion");
    public static final Identifier INFERRED = Identifier.of("inferred");

    private final LazyValue partitionData = LazyValue. builder()
            .initializer(this::loadPartitionData).build();

    private final LazyValue awsPartition = LazyValue. builder().initializer(this::findAwsPartition).build();

    public PartitionFn(FnNode node) {
        super(node);
    }

    public static PartitionFn ofExprs(Expr expr) {
        return new PartitionFn(FnNode.ofExprs(ID, expr));
    }

    @Override
    public  T acceptFnVisitor(FnVisitor visitor) {
        return visitor.visitPartition(this);
    }

    public static PartitionFn fromParam(Parameter param) {
        return PartitionFn.ofExprs(param.expr());
    }

    @Override
    public Value evalArg(Value arg) {
        String regionName = arg.expectString();

        PartitionData data = partitionData.value();

        Partition matchedPartition;
        boolean inferred = false;

        // Known region
        matchedPartition = data.regionMap.get(regionName);
        if (matchedPartition == null) {
            // try matching on region name pattern
            for (Partition p : data.partitions) {
                Pattern regex = Pattern.compile(p.regionRegex());
                if (regex.matcher(regionName).matches()) {
                    matchedPartition = p;
                    inferred = true;
                    break;
                }
            }
        }

        // Couldn't find the region by name or pattern matching. Fallback to 'aws' partition.
        if (matchedPartition == null) {
            matchedPartition = awsPartition.value();
        }

        Outputs matchedOutputs = matchedPartition.outputs();
        return Value.fromRecord(MapUtils.of(NAME, Value.fromStr(matchedPartition.id()), DNS_SUFFIX,
                Value.fromStr(matchedOutputs.dnsSuffix()), DUAL_STACK_DNS_SUFFIX,
                Value.fromStr(matchedOutputs.dualStackDnsSuffix()), SUPPORTS_FIPS, Value.fromBool(matchedOutputs.supportsFips()),
                SUPPORTS_DUAL_STACK, Value.fromBool(matchedOutputs.supportsDualStack()), IMPLICIT_GLOBAL_REGION,
                Value.fromStr(matchedOutputs.implicitGlobalRegion()), INFERRED, Value.fromBool(inferred)));
    }

    private PartitionData loadPartitionData() {
        PartitionDataProvider provider = new DefaultPartitionDataProvider();

        // TODO: support custom partitions.json
        Partitions partitions = provider.loadPartitions();

        PartitionData partitionData = new PartitionData();

        partitions.partitions().forEach(part -> {
            partitionData.partitions.add(part);
            part.regions().forEach((name, override) -> {
                partitionData.regionMap.put(name, part);
            });
        });

        return partitionData;
    }

    private Partition findAwsPartition() {
        return partitionData.value().partitions.stream().filter(p -> p.id().equalsIgnoreCase("aws")).findFirst().orElse(null);
    }

    private static class PartitionData {
        private final List partitions = new ArrayList<>();
        private final Map regionMap = new HashMap<>();
    }

    private static final class LazyValue {
        private final Supplier initializer;
        private T value;
        private boolean initialized;

        private LazyValue(Builder builder) {
            this.initializer = builder.initializer;
        }

        public T value() {
            if (!initialized) {
                value = initializer.get();
                initialized = true;
            }
            return value;
        }

        public static  Builder builder() {
            return new Builder<>();
        }

        public static class Builder {
            private Supplier initializer;

            public Builder initializer(Supplier initializer) {
                this.initializer = initializer;
                return this;
            }

            public LazyValue build() {
                return new LazyValue<>(this);
            }
        }
    }

}