001/*
002 * Licensed to the Apache Software Foundation (ASF) under one or more
003 * contributor license agreements.  See the NOTICE file distributed with
004 * this work for additional information regarding copyright ownership.
005 * The ASF licenses this file to You under the Apache License, Version 2.0
006 * (the "License"); you may not use this file except in compliance with
007 * the License.  You may obtain a copy of the License at
008 *
009 *      http://www.apache.org/licenses/LICENSE-2.0
010 *
011 * Unless required by applicable law or agreed to in writing, software
012 * distributed under the License is distributed on an "AS IS" BASIS,
013 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
014 * See the License for the specific language governing permissions and
015 * limitations under the License.
016 */
017package org.apache.juneau.http;
018
019/**
020 * Optional operator-supplied transform applied to request/response body text before it is written to a REST debug log.
021 *
022 * <p>
023 * This SPI is <b>not</b> a default protection. Body dumping is off by default and is enabled only by the
024 * {@code JUNEAU_REST_DEBUG_ALLOW_DUMP_BODIES} environment-variable master gate. A scrubber only ever runs once that gate
025 * has already permitted dumping; it merely chooses <i>scrubbed-vs-raw</i> body text (e.g. mask fields, drop sections). A
026 * configured scrubber never causes body content to be emitted while the gate is unset.
027 *
028 * <p>
029 * The scrubber is <b>fail-closed</b>: if {@link #scrub(String, String)} throws or returns <jk>null</jk>, the formatter
030 * emits a suppression placeholder instead of the body — it never falls back to the raw, unscrubbed body. A non-<jk>null</jk>
031 * result is still sanitized (control characters escaped) and length-capped before it reaches the log line.
032 *
033 * <p>
034 * Implementations must be <b>thread-safe</b> — the formatter may invoke {@link #scrub(String, String)} concurrently.
035 *
036 * <h5 class='section'>See Also:</h5><ul>
037 *    <li class='link'><a class="doclink" href="https://juneau.apache.org/docs/topics/RestServerLoggingAndDebugging">Logging / Debugging</a>
038 * </ul>
039 *
040 * @since 10.0.0
041 */
042public interface RestDebugBodyScrubber {
043
044   /**
045    * Transforms body text before it is logged.
046    *
047    * @param contentType The body's content type (may be <jk>null</jk> if unknown).
048    * @param body The raw (already byte-capped) body text.
049    * @return The scrubbed body text to log, or <jk>null</jk> to fail closed (the formatter emits a placeholder instead).
050    */
051   String scrub(String contentType, String body);
052}