Fix a bug caused when an already absolute or opaque URI is attempted …

…to be resolved. Resolves #208. (#214)

core/src/main/java/gov/nist/secauto/metaschema/core/metapath/function/library/FnDocumentAvailable.java

@@ -13,6 +13,7 @@
 import gov.nist.secauto.metaschema.core.metapath.function.FunctionUtils;
 import gov.nist.secauto.metaschema.core.metapath.function.IArgument;
 import gov.nist.secauto.metaschema.core.metapath.function.IFunction;
+import gov.nist.secauto.metaschema.core.metapath.function.UriFunctionException;
 import gov.nist.secauto.metaschema.core.metapath.item.IItem;
 import gov.nist.secauto.metaschema.core.metapath.item.atomic.IAnyUriItem;
 import gov.nist.secauto.metaschema.core.metapath.item.atomic.IBooleanItem;
@@ -105,31 +106,32 @@ public static IBooleanItem fnDocAvailable(@NonNull IStringItem documentUri, @Non
    * @return if the document is retrievable
    */
   public static IBooleanItem fnDocAvailable(@NonNull IAnyUriItem documentUri, @NonNull DynamicContext context) {
-    // resolve if possible
-    IAnyUriItem uri = FnResolveUri.fnResolveUri(documentUri, null, context);
-    if (!uri.isAbsolute() && !uri.isOpaque()) {
-      throw new DocumentFunctionException(DocumentFunctionException.ERROR_RETRIEVING_RESOURCE, String
-          .format("No base-uri is available in the static context to resolve the URI '%s'.", documentUri.toString()));
-    }
-
     boolean retval;
+    IAnyUriItem uri;
     try {
-      URLConnection connection = uri.asUri().toURL().openConnection();
+      uri = documentUri.isAbsolute() || documentUri.isOpaque()
+          ? documentUri
+          // if not absolute or opaque, then resolve it to make it absolute
+          : FnResolveUri.fnResolveUri(documentUri, null, context);
+      try {
+        URLConnection connection = uri.asUri().toURL().openConnection();
 
-      if (connection instanceof HttpURLConnection) {
-        HttpURLConnection httpConnection = (HttpURLConnection) connection;
-        httpConnection.setRequestMethod("HEAD");
-        httpConnection.connect();
-        retval = HttpURLConnection.HTTP_OK == httpConnection.getResponseCode();
-        httpConnection.disconnect();
-      } else {
-        connection.connect();
-        retval = true;
+        if (connection instanceof HttpURLConnection) {
+          HttpURLConnection httpConnection = (HttpURLConnection) connection;
+          httpConnection.setRequestMethod("HEAD");
+          httpConnection.connect();
+          retval = HttpURLConnection.HTTP_OK == httpConnection.getResponseCode();
+          httpConnection.disconnect();
+        } else {
+          connection.connect();
+          retval = true;
+        }
+      } catch (IOException ex) {
+        retval = false;
       }
-      return IBooleanItem.valueOf(retval);
-    } catch (IOException ex) {
-      throw new DocumentFunctionException(DocumentFunctionException.ERROR_RETRIEVING_RESOURCE, String
-          .format("Unable to retrieve the resource identified by the URI '%s'.", documentUri.toString()), ex);
+    } catch (UriFunctionException ex) {
+      retval = false;
     }
+    return IBooleanItem.valueOf(retval);
   }
 }

core/src/main/java/gov/nist/secauto/metaschema/core/metapath/function/library/FnResolveUri.java

@@ -177,6 +177,8 @@ public static IAnyUriItem fnResolveUri(
    *          the evaluation context used to get the static base URI if needed
    * @return the resolved URI or {@code null} if the {@code relative} URI in
    *         {@code null}
+   * @throws UriFunctionException
+   *           if the base URI is not configured in the dynamic context
    */
   @NonNull
   public static IAnyUriItem fnResolveUri(

core/src/test/java/gov/nist/secauto/metaschema/core/metapath/function/library/FnDocumentAvailableTest.java

@@ -0,0 +1,23 @@
+
+package gov.nist.secauto.metaschema.core.metapath.function.library;
+
+import static org.junit.jupiter.api.Assertions.assertTrue;
+
+import gov.nist.secauto.metaschema.core.metapath.DynamicContext;
+import gov.nist.secauto.metaschema.core.metapath.item.atomic.IAnyUriItem;
+
+import org.junit.jupiter.api.Test;
+
+class FnDocumentAvailableTest {
+
+  /**
+   * Tests for https://github.com/metaschema-framework/metaschema-java/issues/208.
+   */
+  @Test
+  void issue208Test() {
+    IAnyUriItem uri = IAnyUriItem.valueOf(
+        "https://raw.githubusercontent.com/GSA/fedramp-automation/8301e380c88532ebbb22aca55521701750eb0b83/src/content/awesome-cloud/xml/AwesomeCloudSSP1.xml");
+
+    assertTrue(FnDocumentAvailable.fnDocAvailable(uri, new DynamicContext()).toBoolean());
+  }
+}