Fix PDF/A validation reporting internal_error after veraPDF 1.30.x upgrade

pom.xml

@@ -193,7 +193,7 @@
     <dependency>
       <groupId>org.verapdf</groupId>
       <artifactId>validation-model-jakarta</artifactId>
-      <version>1.28.2</version>
+      <version>1.30.2</version>
     </dependency>
     <dependency>
       <groupId>net.sf.saxon</groupId>

src/main/java/gov/nasa/pds/tools/util/PDFUtil.java

@@ -89,6 +89,20 @@ private synchronized void writeErrorToFile(String baseDir, String pdfFullName, V
     }
   }
 
+  /**
+   * Returns the detected PDF/A flavour for the given parser, or null if the PDF has no
+   * conformance declaration. veraPDF 1.30+ throws IndexOutOfBoundsException (rather than
+   * returning NO_FLAVOUR) when no pdfaid metadata is present.
+   */
+  private PDFAFlavour detectFlavour(PDFAParser parser) {
+    try {
+      PDFAFlavour flavour = parser.getFlavour();
+      return PDFAFlavour.NO_FLAVOUR.equals(flavour) ? null : flavour;
+    } catch (IndexOutOfBoundsException e) {
+      return null;
+    }
+  }
+
   private boolean validatePDF(String baseDir, URI uri, String pdfRef) throws IOException {
     boolean pdfValidateFlag = false;
 
@@ -98,35 +112,31 @@ private boolean validatePDF(String baseDir, URI uri, String pdfRef) throws IOExc
         this.errorMessage = "Zero length file is an invalid PDF file.";
         return pdfValidateFlag;
       }
-      // Create a parser and auto-detect flavour
       PDFAParser parser = Foundries.defaultInstance().createParser(new FileInputStream(pdfRef));
-      PDFAFlavour detectedFlavour = parser.getFlavour();
+      PDFAFlavour detectedFlavour = detectFlavour(parser);
       LOG.debug("validatePDF: parser.getFlavour() [{}]", detectedFlavour);
 
-      // First, check the flavour is valid 1a or 1b
-      if (!detectedFlavour.equals(PDFAFlavour.PDFA_1_A)
+      if (detectedFlavour == null) {
+        this.errorMessage = "File does not contain a PDF/A conformance declaration for " + uri
+            + ". Expected: PDF/A-1a or PDF/A-1b.";
+      } else if (!detectedFlavour.equals(PDFAFlavour.PDFA_1_A)
           && !detectedFlavour.equals(PDFAFlavour.PDFA_1_B)) {
         this.errorMessage = "Invalid PDF/A version detected for " + uri
             + ". Expected: 1a or 1b. Actual: " + detectedFlavour.getId();
       } else {
-        // Next, check the PDF is actually a valid 1a/1b flavour
+        // Check the PDF is actually a valid 1a/1b flavour
         PDFAValidator validator =
             Foundries.defaultInstance().createValidator(detectedFlavour, false);
         this.parserFlavor = parser.getFlavour().getId();
         ValidationResult result = validator.validate(parser);
         if (result.isCompliant()) {
-          // File is a valid PDF
           LOG.debug("validatePDF file " + pdfRef + " is a valid PDF file with flavor "
               + parser.getFlavour().getId());
           pdfValidateFlag = true;
         } else {
           LOG.error("validatePDF file" + pdfRef + " is not valid PDF file with flavor "
               + parser.getFlavour().getId());
-
-          // Write the result to external file so the user can look over in the validate
-          // report.
           this.writeErrorToFile(baseDir, pdfRef, result, parser.getFlavour().getId());
-
           this.errorMessage = "Validation failed for flavour PDF/A-" + detectedFlavour.getId()
               + " in file " + Paths.get(pdfRef).getFileName() + ".";
           if (this.getExternalErrorFilename() != null) this.errorMessage += "  Detailed error output can be found at " + this.getExternalErrorFilename();