fix(ENGKNOW-2382): Fix header for empty NOR results.

gortools/src/main/scala/gorsat/Analysis/ForkWrite.scala

@@ -149,6 +149,8 @@ case class ForkWrite(forkCol: Int,
     header = headerBuilder.toString
   }
 
+  override def isTypeInformationMaintained: Boolean = true
+
   /**
     * Creates OutFile with given name
     * if the path is a directory save a file with generated md5 sum as name under directory

gortools/src/main/scala/gorsat/Commands/Write.scala

@@ -118,8 +118,6 @@ class Write extends CommandInfo("WRITE",
       throw new GorParsingException("Option -noheader (skip header) is not valid with gor/gorz/nor/norz")
     }
 
-    val fixedHeader = forcedInputHeader.split("\t").slice(0, 2).mkString("\t")
-
     CommandParsingResult(
       ForkWrite(forkCol,
         fileName,
@@ -146,7 +144,7 @@ class Write extends CommandInfo("WRITE",
           maxseg = maxseg
         )
       ),
-      fixedHeader
+      forcedInputHeader
     )
   }
 }

gortools/src/test/java/gorsat/UTestGorWrite.java

@@ -198,7 +198,7 @@ public void testGorWriteColumnNumber() {
         tmpfile.toFile().deleteOnExit();
         String query = "gor ../tests/data/gor/genes.gorz | write -m " + tmpfile.toAbsolutePath().normalize();
         String headerRes = TestUtils.runGorPipe(query);
-        Assert.assertEquals("", "Chrom\tgene_start\n", headerRes);
+        Assert.assertEquals("", "Chrom\tgene_start\tgene_end\tGene_Symbol\n", headerRes);
     }
 
     @Test

gortools/src/test/java/gorsat/monitors/StatsMonitorTest.java

@@ -71,7 +71,7 @@ public void testRowCountAndBytesCountForSelfWriting() {
             }
         }
 
-        assertEquals("", statsMonitor.getHeader());
+        assertEquals("chrom\tpos\ta", statsMonitor.getHeader());
         assertEquals(0, statsMonitor.rowCount());
         assertEquals(0, statsMonitor.bytesCount());
     }

model/src/main/java/org/gorpipe/gor/model/DbConnectionCache.java

@@ -49,7 +49,7 @@ public DbConnection lookup(String source) {
      * @throws IOException
      */
     @SuppressWarnings("WeakerAccess") // Used from gor-services
-    public void initializeDbSources(String credpath) throws ClassNotFoundException, IOException {
+    public void initializeDbSources(String credpath) throws IOException {
         clearDbSources();
         if (credpath != null && credpath.trim().length() > 0) {
             final Path path = Paths.get(credpath);
@@ -62,7 +62,12 @@ public void initializeDbSources(String credpath) throws ClassNotFoundException,
             List<String[]> partsList = parseLinesForDbSourceInstallation(credpath, lines);
 
             for (String[] parts : partsList) {
-                installDbSourceFromParts(parts);
+                try {
+                    installDbSourceFromParts(parts);
+                } catch (ClassNotFoundException e) {
+                    log.error("Failed to load driver class {} for db source {}. Please ensure the driver is in the classpath.",
+                            parts[1], parts[0], e);
+                }
             }
         } else {
             log.info("No db credential path specified");