Fix logged exception for dependency URIs representing directories

Author: smola

telemetry/src/main/java/datadog/telemetry/dependency/DependencyResolver.java

@@ -2,6 +2,7 @@
 
 import java.io.File;
 import java.io.FileInputStream;
+import java.io.IOException;
 import java.io.InputStream;
 import java.net.URI;
 import java.util.Collections;
@@ -12,41 +13,48 @@
 public class DependencyResolver {
 
   private static final Logger log = LoggerFactory.getLogger(DependencyResolver.class);
-  private static final String JAR_SUFFIX = ".jar";
 
   public static List<Dependency> resolve(URI uri) {
-    final String scheme = uri.getScheme();
     try {
-      JarReader.Extracted metadata = null;
-      String path = null;
-      if ("file".equals(scheme)) {
-        File f;
-        if (uri.isOpaque()) {
-          f = new File(uri.getSchemeSpecificPart());
-        } else {
-          f = new File(uri);
-        }
-        path = f.getAbsolutePath();
-        metadata = JarReader.readJarFile(path);
-      } else if ("jar".equals(scheme) && uri.getSchemeSpecificPart().startsWith("file:")) {
-        path = uri.getSchemeSpecificPart().substring("file:".length());
-        metadata = JarReader.readNestedJarFile(path);
-      } else {
-        log.debug("unsupported dependency type: {}", uri);
-        return Collections.emptyList();
-      }
-      final List<Dependency> dependencies =
-          Dependency.fromMavenPom(metadata.jarName, metadata.pomProperties);
-      if (!dependencies.isEmpty()) {
-        return dependencies;
-      }
-      try (final InputStream is = new FileInputStream(path)) {
-        return Collections.singletonList(
-            Dependency.guessFallbackNoPom(metadata.manifest, metadata.jarName, is));
-      }
+      return internalResolve(uri);
     } catch (Throwable t) {
       log.debug("Failed to determine dependency for uri {}", uri, t);
     }
     return Collections.emptyList();
   }
+
+  static List<Dependency> internalResolve(final URI uri) throws IOException {
+    final String scheme = uri.getScheme();
+    JarReader.Extracted metadata;
+    String path;
+    if ("file".equals(scheme)) {
+      File f;
+      if (uri.isOpaque()) {
+        f = new File(uri.getSchemeSpecificPart());
+      } else {
+        f = new File(uri);
+      }
+      path = f.getAbsolutePath();
+      metadata = JarReader.readJarFile(path);
+    } else if ("jar".equals(scheme) && uri.getSchemeSpecificPart().startsWith("file:")) {
+      path = uri.getSchemeSpecificPart().substring("file:".length());
+      metadata = JarReader.readNestedJarFile(path);
+    } else {
+      log.debug("unsupported dependency type: {}", uri);
+      return Collections.emptyList();
+    }
+    if (metadata.isDirectory) {
+      log.debug("Extracting dependencies from directories is not supported: {}", uri);
+      return Collections.emptyList();
+    }
+    final List<Dependency> dependencies =
+        Dependency.fromMavenPom(metadata.jarName, metadata.pomProperties);
+    if (!dependencies.isEmpty()) {
+      return dependencies;
+    }
+    try (final InputStream is = new FileInputStream(path)) {
+      return Collections.singletonList(
+          Dependency.guessFallbackNoPom(metadata.manifest, metadata.jarName, is));
+    }
+  }
 }

telemetry/src/main/java/datadog/telemetry/dependency/JarReader.java

@@ -19,18 +19,25 @@ static class Extracted {
     final String jarName;
     final Map<String, Properties> pomProperties;
     final Attributes manifest;
+    final boolean isDirectory;
 
     public Extracted(
         final String jarName,
         final Map<String, Properties> pomProperties,
-        final Attributes manifest) {
+        final Attributes manifest,
+        final boolean isDirectory) {
       this.jarName = jarName;
       this.pomProperties = pomProperties;
       this.manifest = manifest;
+      this.isDirectory = isDirectory;
     }
   }
 
   public static Extracted readJarFile(String jarPath) throws IOException {
+    final File jarFile = new File(jarPath);
+    if (jarFile.isDirectory()) {
+      return new Extracted(jarFile.getName(), new HashMap<>(), new Attributes(), true);
+    }
     try (final JarFile jar = new JarFile(jarPath, false /* no verify */)) {
       final Map<String, Properties> pomProperties = new HashMap<>();
       final Enumeration<? extends ZipEntry> entries = jar.entries();
@@ -47,7 +54,7 @@ public static Extracted readJarFile(String jarPath) throws IOException {
       final Manifest manifest = jar.getManifest();
       final Attributes attributes =
           (manifest == null) ? new Attributes() : manifest.getMainAttributes();
-      return new Extracted(new File(jar.getName()).getName(), pomProperties, attributes);
+      return new Extracted(new File(jar.getName()).getName(), pomProperties, attributes, false);
     }
   }
 
@@ -66,6 +73,10 @@ public static Extracted readNestedJarFile(final String jarPath) throws IOExcepti
       if (entry == null) {
         throw new NoSuchFileException("Nested jar not found: " + jarPath);
       }
+      if (entry.isDirectory()) {
+        return new Extracted(
+            new File(innerJarPath).getName(), new HashMap<>(), new Attributes(), true);
+      }
       try (final InputStream is = outerJar.getInputStream(entry);
           final JarInputStream innerJar = new JarInputStream(is, false /* no verify */)) {
         final Map<String, Properties> pomProperties = new HashMap<>();
@@ -80,7 +91,7 @@ public static Extracted readNestedJarFile(final String jarPath) throws IOExcepti
         final Manifest manifest = innerJar.getManifest();
         final Attributes attributes =
             (manifest == null) ? new Attributes() : manifest.getMainAttributes();
-        return new Extracted(new File(innerJarPath).getName(), pomProperties, attributes);
+        return new Extracted(new File(innerJarPath).getName(), pomProperties, attributes, false);
       }
     }
   }

telemetry/src/test/groovy/datadog/telemetry/dependency/DependencyResolverSpecification.groovy

@@ -192,6 +192,46 @@ class DependencyResolverSpecification extends DepSpecification {
       hash: '6438819DAB9C9AC18D8A6922C8A923C2ADAEA85D')
   }
 
+  void 'attempt to extract dependencies from directory'() {
+    given:
+    File dir = new File(testDir, 'dir')
+    dir.mkdirs()
+
+    when:
+    def deps = DependencyResolver.resolve(dir.toURI())
+
+    then:
+    deps.isEmpty()
+
+    when: 'resolve without catching exceptions'
+    deps = DependencyResolver.internalResolve(dir.toURI())
+
+    then: 'it does not throw'
+    deps.isEmpty()
+  }
+
+  void 'attempt to extract dependencies from directory within jar'() {
+    given:
+    File file = new File(testDir, "app.jar")
+    ZipOutputStream out = new ZipOutputStream(new FileOutputStream(file))
+    ZipEntry e = new ZipEntry("classes/")
+    out.putNextEntry(e)
+    out.closeEntry()
+    out.close()
+
+    when:
+    def deps = DependencyResolver.resolve(new URI('jar:file:' + file.getAbsolutePath() + "!/classes!/"))
+
+    then:
+    deps.isEmpty()
+
+    when: 'resolve without catching exceptions'
+    deps = DependencyResolver.internalResolve(new URI('jar:file:' + file.getAbsolutePath() + "!/classes!/"))
+
+    then: 'it does not throw'
+    deps.isEmpty()
+  }
+
   private static void knownJarCheck(Map opts) {
     File jarFile = getJar(opts['jarName'])
     List<Dependency> deps = DependencyResolver.resolve(jarFile.toURI())