1 /*
2  * Copyright Amazon.com, Inc. or its affiliates. All Rights Reserved.
3  *
4  * Licensed under the Apache License, Version 2.0 (the "License").
5  * You may not use this file except in compliance with the License.
6  * A copy of the License is located at
7  *
8  *  http://aws.amazon.com/apache2.0
9  *
10  * or in the "license" file accompanying this file. This file is distributed
11  * on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either
12  * express or implied. See the License for the specific language governing
13  * permissions and limitations under the License.
14  */
15 
16 package software.amazon.awssdk.protocols.query.internal.marshall;
17 
18 import java.util.List;
19 import software.amazon.awssdk.annotations.SdkInternalApi;
20 import software.amazon.awssdk.core.SdkField;
21 import software.amazon.awssdk.core.traits.ListTrait;
22 import software.amazon.awssdk.core.util.SdkAutoConstructList;
23 
24 /**
25  * Marshaller for list types.
26  */
27 @SdkInternalApi
28 public class ListQueryMarshaller implements QueryMarshaller<List<?>> {
29 
30     private final PathResolver pathResolver;
31 
ListQueryMarshaller(PathResolver pathResolver)32     private ListQueryMarshaller(PathResolver pathResolver) {
33         this.pathResolver = pathResolver;
34     }
35 
36     @Override
marshall(QueryMarshallerContext context, String path, List<?> val, SdkField<List<?>> sdkField)37     public void marshall(QueryMarshallerContext context, String path, List<?> val, SdkField<List<?>> sdkField) {
38         // Explicitly empty lists are marshalled as a query param with empty value in AWS/Query
39         if (val.isEmpty() && !(val instanceof SdkAutoConstructList)) {
40             context.request().putRawQueryParameter(path, "");
41             return;
42         }
43         for (int i = 0; i < val.size(); i++) {
44             ListTrait listTrait = sdkField.getTrait(ListTrait.class);
45             String listPath = pathResolver.resolve(path, i, listTrait);
46             QueryMarshaller<Object> marshaller = context.marshallerRegistry().getMarshaller(
47                 ((SdkField<?>) listTrait.memberFieldInfo()).marshallingType(), val);
48             marshaller.marshall(context, listPath, val.get(i), listTrait.memberFieldInfo());
49         }
50     }
51 
52     @FunctionalInterface
53     private interface PathResolver {
54 
resolve(String path, int i, ListTrait listTrait)55         String resolve(String path, int i, ListTrait listTrait);
56     }
57 
58     /**
59      * Wires up the {@link ListQueryMarshaller} with a {@link PathResolver} that respects the flattened trait.
60      *
61      * @return ListQueryMarshaller.
62      */
awsQuery()63     public static ListQueryMarshaller awsQuery() {
64         return new ListQueryMarshaller((path, i, listTrait) ->
65                                            listTrait.isFlattened() ?
66                                            String.format("%s.%d", path, i + 1) :
67                                            String.format("%s.%s.%d", path, listTrait.memberFieldInfo().locationName(), i + 1));
68     }
69 
70     /**
71      * Wires up the {@link ListQueryMarshaller} with a {@link PathResolver} that always flattens lists. The EC2 protocol
72      * always flattens lists for inputs even when the 'flattened' trait is not present.
73      *
74      * @return ListQueryMarshaller.
75      */
ec2Query()76     public static ListQueryMarshaller ec2Query() {
77         return new ListQueryMarshaller((path, i, listTrait) -> String.format("%s.%d", path, i + 1));
78     }
79 }
80