Copilot commented on code in PR #2880: URL: https://github.com/apache/tika/pull/2880#discussion_r3369949293
########## tika-core/src/main/java/org/apache/tika/config/TikaExtras.java: ########## @@ -0,0 +1,161 @@ +/* + * Licensed to the Apache Software Foundation (ASF) under one or more + * contributor license agreements. See the NOTICE file distributed with + * this work for additional information regarding copyright ownership. + * The ASF licenses this file to You 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 org.apache.tika.config; + +import java.net.URL; +import java.net.URLClassLoader; +import java.nio.file.DirectoryStream; +import java.nio.file.Files; +import java.nio.file.Path; +import java.util.ArrayList; +import java.util.Collections; +import java.util.Comparator; +import java.util.List; + +import org.slf4j.Logger; +import org.slf4j.LoggerFactory; + +/** + * Opt-in mechanism for adding user-supplied "extras" jars (extra + * {@code EncodingDetector}s, {@code Parser}s, etc.) to Tika's SPI discovery + * without repackaging the application. + * + * <p><b>Off by default.</b> Nothing is loaded unless the + * {@value #EXTRAS_DIR_PROPERTY} system property points at a directory; then every + * {@code *.jar} in it is made visible to service-loading. There is no implicit or + * default directory — the feature is off unless the property is set. (A relative + * property value is resolved against the process working directory, like any path.) + * + * <p><b>Security:</b> this is a trusted code directory — anything in it runs with + * the full privileges of the Tika process. Treat write access to it exactly like + * write access to {@code lib/}; it must not be writable by less-trusted principals + * (for servers, not reachable by request handling). Being opt-in keeps "we are + * now loading extra code" an explicit, auditable choice. + */ +public final class TikaExtras { + + /** System property naming the extras directory. Unset = feature off. */ + public static final String EXTRAS_DIR_PROPERTY = "tika.extras.dir"; + + private static final Logger LOG = LoggerFactory.getLogger(TikaExtras.class); + + private TikaExtras() { + } + + /** + * If {@value #EXTRAS_DIR_PROPERTY} is set, installs a classloader over the + * {@code *.jar} files in that directory as the thread + Tika + * {@link ServiceLoader} context classloader, so they join SPI discovery. + * No-op (returns {@code null}) when the property is unset or the directory is + * missing/empty. Call exactly once at startup, before any Tika component is + * loaded: each call builds a new classloader, so repeated calls stack them and + * leave the earlier ones' open jar handles dangling. + * + * @return the installed classloader, or {@code null} if extras are off/empty + */ + public static ClassLoader install() { + List<Path> jars = extraJars(); + if (jars.isEmpty()) { + return null; + } + List<URL> urls = new ArrayList<>(jars.size()); + List<Path> loaded = new ArrayList<>(jars.size()); + for (Path jar : jars) { + try { + urls.add(jar.toUri().toURL()); + loaded.add(jar); + } catch (Exception e) { + LOG.warn("Skipping extra jar {}: {}", jar, e.toString()); + } + } + if (urls.isEmpty()) { + return null; + } + ClassLoader parent = Thread.currentThread().getContextClassLoader(); + if (parent == null) { + parent = TikaExtras.class.getClassLoader(); + } + URLClassLoader cl = new URLClassLoader(urls.toArray(new URL[0]), parent); + Thread.currentThread().setContextClassLoader(cl); + ServiceLoader.setContextClassLoader(cl); + LOG.info("{}: loaded {} extra jar(s): {}", EXTRAS_DIR_PROPERTY, loaded.size(), loaded); + return cl; + } + + /** + * The {@code *.jar} files in the {@value #EXTRAS_DIR_PROPERTY} directory — for + * callers that extend a forked process's classpath rather than installing a + * classloader. Empty when the property is unset or the directory is + * missing/has no jars. + */ + public static List<Path> extraJars() { + Path dir = extrasDir(); + if (dir == null || !Files.isDirectory(dir)) { + return Collections.emptyList(); + } + List<Path> jars = new ArrayList<>(); + try (DirectoryStream<Path> stream = Files.newDirectoryStream(dir, "*.jar")) { + for (Path jar : stream) { + jars.add(jar); + } + } catch (Exception e) { + LOG.warn("Could not scan {}={}: {}", EXTRAS_DIR_PROPERTY, dir, e.toString()); + } + // Sort by file name so jar load order (classloader URL order / forked-child + // classpath order, hence SPI precedence) is deterministic across platforms + // and filesystems rather than depending on directory iteration order. + jars.sort(Comparator.comparing(jar -> jar.getFileName().toString())); + return jars; + } + + /** + * Appends the {@link #extraJars()} (as absolute paths, joined with the + * platform path separator) to the given classpath string — for extending a + * forked process's {@code -cp} with the extras jars. Returns {@code classpath} + * unchanged when the feature is off or the directory has no jars. + * + * @param classpath the base classpath to extend + * @return the classpath with any extras jars appended + */ + public static String appendJarsToClasspath(String classpath) { + List<Path> jars = extraJars(); + if (jars.isEmpty()) { + return classpath; + } + String separator = System.getProperty("path.separator"); + StringBuilder sb = new StringBuilder(); + if (classpath != null && !classpath.isEmpty()) { + sb.append(classpath); + } + for (Path jar : jars) { + if (sb.length() > 0) { + sb.append(separator); + } + sb.append(jar.toAbsolutePath()); + } + return sb.toString(); + } + + /** The configured extras directory, or {@code null} if the feature is off. */ + public static Path extrasDir() { + String prop = System.getProperty(EXTRAS_DIR_PROPERTY); + if (prop == null || prop.isBlank()) { + return null; + } + return Path.of(prop.trim()); + } Review Comment: `extrasDir()` calls `Path.of(prop.trim())` without handling `InvalidPathException` (a `RuntimeException`). A malformed `-Dtika.extras.dir=...` value would currently abort startup (e.g., via `TikaExtras.install()` in `main`). It’s safer to treat an invalid path like "feature off" and log a warning instead of crashing. -- This is an automated message from the Apache Git Service. To respond to the message, please log on to GitHub and use the URL above to go to the specific comment. To unsubscribe, e-mail: [email protected] For queries about this service, please contact Infrastructure at: [email protected]
