REF-7: Support non-file resource URLs (WildFly/JBoss vfs:) in ResourceUtil (issue #80)

oiosaml/src/main/java/dk/gov/oio/saml/util/ResourceUtil.java

@@ -8,6 +8,7 @@
 import java.net.URL;
 import java.nio.file.Files;
 import java.nio.file.Path;
+import java.nio.file.Paths;
 import java.nio.file.StandardCopyOption;
 import java.util.Enumeration;
 import java.util.HashMap;
@@ -28,21 +29,8 @@ public static File getResourceAsFile(String resourceName) throws InternalExcepti
             throw new InternalException(String.format("Unable to load resource file '%s'", resourceName));
         }
         try {
-            File file;
             URL url = ResourceUtil.getClassLoader().getResource(resourceName);
-
-            if (url != null && "jar".equals(url.getProtocol())) {
-                // To access resources as files inside a jar we need to copy them to disk (use when unable to access as stream)
-                try (InputStream inputStream = ResourceUtil.getResourceAsStream(resourceName)) {
-                    Path path = Files.createTempFile(resourceName, "tmp");
-                    java.nio.file.Files.copy(inputStream, path, StandardCopyOption.REPLACE_EXISTING);
-                    file = path.toFile();
-                }
-            } else if (url != null) {
-                file = new File(url.toURI());
-            } else {
-                file = new File(resourceName);
-            }
+            File file = toFile(url, resourceName);
 
             if (!file.exists()) {
                 throw new InternalException(String.format("Unable to load resource file '%s'", resourceName));
@@ -55,6 +43,42 @@ public static File getResourceAsFile(String resourceName) throws InternalExcepti
         }
     }
 
+    /**
+     * Resolve a classpath resource URL to a {@link File}.
+     * <p>
+     * A plain {@code file:} URL is used directly. Resources that are not backed by a real
+     * filesystem file - inside a jar ({@code jar:}), or served by an application server
+     * virtual file system such as WildFly/JBoss ({@code vfs:}, {@code vfszip:}) - cannot be
+     * turned into a File with {@code new File(url.toURI())} (that throws
+     * {@code IllegalArgumentException: URI scheme is not "file"}), so they are copied to a
+     * temporary file through their stream instead. See issue #80.
+     *
+     * @param url URL returned by the classloader, or {@code null} when the resource is not on the classpath
+     * @param resourceName original resource name, used as the absolute/external path fallback when {@code url} is null
+     * @return file pointing to the resource
+     */
+    static File toFile(URL url, String resourceName) throws URISyntaxException, IOException {
+        if (url != null && "file".equals(url.getProtocol())) {
+            return new File(url.toURI());
+        }
+
+        if (url != null) {
+            // Not a plain file (jar:, vfs:, vfszip:, ...) - copy to disk so it can be read as a File.
+            // Use only the last path segment as the temp-file prefix: a resourceName that refers to a
+            // file in a subdirectory (e.g. "config/oiosaml.properties") contains '/', which
+            // createTempFile rejects with IllegalArgumentException. The "oiosaml-" prefix also
+            // guarantees the minimum 3-character length required for the prefix.
+            try (InputStream inputStream = url.openStream()) {
+                String baseName = Paths.get(resourceName).getFileName().toString();
+                Path path = Files.createTempFile("oiosaml-" + baseName, ".tmp");
+                Files.copy(inputStream, path, StandardCopyOption.REPLACE_EXISTING);
+                return path.toFile();
+            }
+        }
+
+        return new File(resourceName);
+    }
+
     /**
      * Returns an input stream for reading the specified resource.
      * @param resourceName Resource name from classpath or absolute path to resource

oiosaml/src/test/java/dk/gov/oio/saml/util/ResourceUtilTest.java

@@ -6,6 +6,9 @@
 import java.io.File;
 import java.io.IOException;
 import java.io.InputStream;
+import java.net.URL;
+import java.net.URLConnection;
+import java.net.URLStreamHandler;
 import java.nio.charset.StandardCharsets;
 import java.nio.file.Files;
 import java.nio.file.Path;
@@ -44,6 +47,61 @@ void testGetResourceAsFileFromJar() throws InternalException {
         Assertions.assertTrue(file.isFile() && file.canRead());
     }
 
+    @DisplayName("Test GetResourceAsFile handles non-file (WildFly vfs:) URLs - issue #80")
+    @Test
+    void testToFileFromVfsUrl() throws Exception {
+        // Simulate an application-server VFS resource URL (e.g. WildFly 'vfs:') backed by a
+        // real file. Such URLs are not 'file:' URLs, so the old new File(url.toURI()) approach
+        // throws; toFile must instead copy the resource to a readable temp file.
+        URLStreamHandler vfsHandler = new URLStreamHandler() {
+            @Override
+            protected URLConnection openConnection(URL u) {
+                return new URLConnection(u) {
+                    @Override public void connect() { }
+                    @Override public InputStream getInputStream() throws IOException {
+                        return Files.newInputStream(externalPath);
+                    }
+                };
+            }
+        };
+        URL vfsUrl = new URL(null, "vfs:/content/app.war/WEB-INF/classes/oiosaml.properties", vfsHandler);
+
+        // The naive conversion that caused issue #80 fails for such URLs...
+        Assertions.assertThrows(IllegalArgumentException.class, () -> new File(vfsUrl.toURI()));
+
+        // ...while toFile resolves it to a readable file holding the original content.
+        File file = ResourceUtil.toFile(vfsUrl, "oiosaml.properties");
+        Assertions.assertTrue(file.isFile() && file.canRead());
+        Assertions.assertEquals("this.is.a.test=1234",
+                new String(Files.readAllBytes(file.toPath()), StandardCharsets.UTF_8));
+    }
+
+    @DisplayName("Test GetResourceAsFile handles non-file URLs whose resource is in a subdirectory - issue #80")
+    @Test
+    void testToFileFromVfsUrlInSubdirectory() throws Exception {
+        // A resource that lives in a subdirectory (e.g. "config/oiosaml.properties") has a
+        // resourceName containing '/'. createTempFile rejects such a value as a prefix
+        // (IllegalArgumentException: Invalid prefix or suffix), so toFile must use only the
+        // last path segment. Regression guard for the subdirectory case of issue #80.
+        URLStreamHandler vfsHandler = new URLStreamHandler() {
+            @Override
+            protected URLConnection openConnection(URL u) {
+                return new URLConnection(u) {
+                    @Override public void connect() { }
+                    @Override public InputStream getInputStream() throws IOException {
+                        return Files.newInputStream(externalPath);
+                    }
+                };
+            }
+        };
+        URL vfsUrl = new URL(null, "vfs:/content/app.war/WEB-INF/classes/config/oiosaml.properties", vfsHandler);
+
+        File file = ResourceUtil.toFile(vfsUrl, "config/oiosaml.properties");
+        Assertions.assertTrue(file.isFile() && file.canRead());
+        Assertions.assertEquals("this.is.a.test=1234",
+                new String(Files.readAllBytes(file.toPath()), StandardCharsets.UTF_8));
+    }
+
     @DisplayName("Test GetResourceAsStream from classpath")
     @Test
     void testGetResourceAsStreamFromClassPath() throws IOException, InternalException {