TIKA-4864: resolve the default plugins dir against the install layout and make it absolute

Author: dschmidt

tika-server/tika-server-core/src/main/java/org/apache/tika/server/core/TikaServerProcess.java

@@ -727,28 +727,40 @@ private static PipesParsingHelper initPipesParsingHelper(TikaServerConfig tikaSe
 
     /**
      * Resolves the default plugins directory. Looks for a "plugins" directory
-     * next to the running jar first, then falls back to the current working directory.
+     * next to the jar this class was loaded from, then next to that directory's
+     * parent (the class may live in a "lib" directory beside the server jar),
+     * then in the current working directory. Always returns an absolute path,
+     * so the forked pipes server does not depend on its own working directory.
      */
     private static String resolveDefaultPluginsDir() {
+        Path codeSourceDir = null;
         try {
             Path jarPath = Path.of(
                     TikaServerProcess.class.getProtectionDomain()
                             .getCodeSource().getLocation().toURI());
-            Path jarDir = jarPath.getParent();
-            if (jarDir != null) {
-                Path pluginsNextToJar = jarDir.resolve(DEFAULT_PLUGINS_DIR);
-                if (Files.isDirectory(pluginsNextToJar)) {
-                    return pluginsNextToJar.toAbsolutePath().toString();
-                }
-            }
+            codeSourceDir = jarPath.getParent();
         } catch (Exception e) {
-            // Fall through to cwd-relative
+            // no code source, probe the working directory only
         }
-        Path cwdPlugins = Path.of(DEFAULT_PLUGINS_DIR);
-        if (Files.isDirectory(cwdPlugins)) {
-            return cwdPlugins.toAbsolutePath().toString();
+        return resolveDefaultPluginsDir(codeSourceDir, Path.of("")).toString();
+    }
+
+    // package-private for testing
+    static Path resolveDefaultPluginsDir(Path codeSourceDir, Path cwd) {
+        if (codeSourceDir != null) {
+            Path nextToJar = codeSourceDir.resolve(DEFAULT_PLUGINS_DIR);
+            if (Files.isDirectory(nextToJar)) {
+                return nextToJar.toAbsolutePath();
+            }
+            Path parent = codeSourceDir.getParent();
+            if (parent != null) {
+                Path nextToParent = parent.resolve(DEFAULT_PLUGINS_DIR);
+                if (Files.isDirectory(nextToParent)) {
+                    return nextToParent.toAbsolutePath();
+                }
+            }
         }
-        return DEFAULT_PLUGINS_DIR;
+        return cwd.resolve(DEFAULT_PLUGINS_DIR).toAbsolutePath();
     }
 
     /**

tika-server/tika-server-core/src/test/java/org/apache/tika/server/core/TikaServerProcessTest.java

@@ -23,11 +23,14 @@
 import static org.junit.jupiter.api.Assertions.assertThrows;
 import static org.junit.jupiter.api.Assertions.assertTrue;
 
+import java.nio.file.Files;
+import java.nio.file.Path;
 import java.util.ArrayList;
 import java.util.List;
 import java.util.Set;
 
 import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.io.TempDir;
 
 import org.apache.tika.exception.TikaConfigException;
 import org.apache.tika.server.core.resource.MetadataResource;
@@ -41,6 +44,36 @@ private static TikaServerConfig config(boolean allowPipes, String... endpoints)
         return c;
     }
 
+    @Test
+    public void pluginsDirNextToTheCodeSourceJar(@TempDir Path install) throws Exception {
+        Path plugins = Files.createDirectories(install.resolve("plugins"));
+        assertEquals(plugins.toAbsolutePath(),
+                TikaServerProcess.resolveDefaultPluginsDir(install, Path.of("")));
+    }
+
+    @Test
+    public void pluginsDirBesideTheLibDirectory(@TempDir Path install) throws Exception {
+        // the resolving class lives in lib/, the plugins next to the server jar
+        Path lib = Files.createDirectories(install.resolve("lib"));
+        Path plugins = Files.createDirectories(install.resolve("plugins"));
+        assertEquals(plugins.toAbsolutePath(),
+                TikaServerProcess.resolveDefaultPluginsDir(lib, Path.of("")));
+    }
+
+    @Test
+    public void pluginsDirFromTheWorkingDirectory(@TempDir Path install, @TempDir Path cwd)
+            throws Exception {
+        Path plugins = Files.createDirectories(cwd.resolve("plugins"));
+        assertEquals(plugins.toAbsolutePath(),
+                TikaServerProcess.resolveDefaultPluginsDir(install.resolve("lib"), cwd));
+    }
+
+    @Test
+    public void missingPluginsDirStaysAbsolute(@TempDir Path cwd) {
+        // the forked pipes server must not re-resolve the path against its own cwd
+        assertTrue(TikaServerProcess.resolveDefaultPluginsDir(null, cwd).isAbsolute());
+    }
+
     @Test
     public void pipesAndAsyncRequireAllowPipes() {
         // The pipes/async endpoints fork processes and read/write via fetchers/emitters; the