001/*
002 * Copyright 2022-2025 Revetware LLC.
003 *
004 * Licensed under the Apache License, Version 2.0 (the "License");
005 * you may not use this file except in compliance with the License.
006 * You may obtain a copy of the License at
007 *
008 * http://www.apache.org/licenses/LICENSE-2.0
009 *
010 * Unless required by applicable law or agreed to in writing, software
011 * distributed under the License is distributed on an "AS IS" BASIS,
012 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
013 * See the License for the specific language governing permissions and
014 * limitations under the License.
015 */
016
017package com.soklet;
018
019import javax.annotation.Nonnull;
020import java.util.Map;
021import java.util.Set;
022
023/**
024 * Contract for parsing HTML form fields encoded according to the <a href="https://datatracker.ietf.org/doc/html/rfc7578">{@code multipart/form-data}</a> specification.
025 * <p>
026 * A standard threadsafe implementation can be acquired via the {@link #defaultInstance()} factory method.
027 * <p>
028 * See <a href="https://www.soklet.com/docs/request-handling#multipart-form-data">https://www.soklet.com/docs/request-handling#multipart-form-data</a> for detailed documentation.
029 *
030 * @author <a href="https://www.revetkn.com">Mark Allen</a>
031 */
032@FunctionalInterface
033public interface MultipartParser {
034        /**
035         * Given a request, detect all HTML form fields with <a href="https://datatracker.ietf.org/doc/html/rfc7578">{@code multipart/form-data}</a> encoding and parse their values.
036         *
037         * @param request the request to parse
038         * @return a mapping of form field names to corresponding sets of form field values
039         */
040        @Nonnull
041        Map<String, Set<MultipartField>> extractMultipartFields(@Nonnull Request request);
042
043        /**
044         * Acquires a threadsafe {@link MultipartParser}.
045         * <p>
046         * The returned instance is guaranteed to be a JVM-wide singleton.
047         *
048         * @return a {@code MultipartParser} instance
049         */
050        @Nonnull
051        static MultipartParser defaultInstance() {
052                return DefaultMultipartParser.defaultInstance();
053        }
054}