[QTL] adding listDelimiter to lookup parser spec (#2941)

* adding listDelimiter to lookup parser spec

* cleaning code

docs/content/development/extensions-core/namespaced-lookup.md

@@ -151,6 +151,7 @@ truck,something3,buck
 |`keyColumn`|The name of the column containing the key|no|The first column|
 |`valueColumn`|The name of the column containing the value|no|The second column|
 |`delimiter`|The delimiter in the file|no|tab (`\t`)|
+|`listDelimiter`|The list delimiter in the file|no| (`\u0001`)|
 
 
 *example input*

extensions-core/namespace-lookup/src/main/java/io/druid/query/extraction/namespace/URIExtractionNamespace.java

@@ -356,6 +356,7 @@ public class URIExtractionNamespace implements ExtractionNamespace
     private final Parser<String, String> parser;
     private final List<String> columns;
     private final String delimiter;
+    private final String listDelimiter;
     private final String keyColumn;
     private final String valueColumn;
 
@@ -363,6 +364,7 @@ public class URIExtractionNamespace implements ExtractionNamespace
     public TSVFlatDataParser(
         @JsonProperty("columns") List<String> columns,
         @JsonProperty("delimiter") String delimiter,
+        @JsonProperty("listDelimiter") String listDelimiter,
         @JsonProperty("keyColumn") final String keyColumn,
         @JsonProperty("valueColumn") final String valueColumn
     )
@@ -372,8 +374,8 @@ public class URIExtractionNamespace implements ExtractionNamespace
           "Must specify more than one column to have a key value pair"
       );
       final DelimitedParser delegate = new DelimitedParser(
-          Optional.fromNullable(Strings.isNullOrEmpty(delimiter) ? null : delimiter),
-          Optional.<String>absent()
+          Optional.fromNullable(Strings.emptyToNull(delimiter)),
+          Optional.fromNullable(Strings.emptyToNull(listDelimiter))
       );
       Preconditions.checkArgument(
           !(Strings.isNullOrEmpty(keyColumn) ^ Strings.isNullOrEmpty(valueColumn)),
@@ -382,6 +384,7 @@ public class URIExtractionNamespace implements ExtractionNamespace
       delegate.setFieldNames(columns);
       this.columns = columns;
       this.delimiter = delimiter;
+      this.listDelimiter = listDelimiter;
       this.keyColumn = Strings.isNullOrEmpty(keyColumn) ? columns.get(0) : keyColumn;
       this.valueColumn = Strings.isNullOrEmpty(valueColumn) ? columns.get(1) : valueColumn;
       Preconditions.checkArgument(
@@ -418,6 +421,12 @@ public class URIExtractionNamespace implements ExtractionNamespace
       return this.valueColumn;
     }
 
+    @JsonProperty
+    public String getListDelimiter()
+    {
+      return listDelimiter;
+    }
+
     @JsonProperty
     public String getDelimiter()
     {
@@ -434,9 +443,10 @@ public class URIExtractionNamespace implements ExtractionNamespace
     public String toString()
     {
       return String.format(
-          "TSVFlatDataParser = { columns = %s, delimiter = '%s', keyColumn = %s, valueColumn = %s }",
+          "TSVFlatDataParser = { columns = %s, delimiter = '%s', listDelimiter = '%s',keyColumn = %s, valueColumn = %s }",
           Arrays.toString(columns.toArray()),
           delimiter,
+          listDelimiter,
           keyColumn,
           valueColumn
       );

extensions-core/namespace-lookup/src/test/java/io/druid/query/extraction/namespace/URIExtractionNamespaceTest.java

@@ -121,19 +121,31 @@ public class URIExtractionNamespaceTest
     URIExtractionNamespace.TSVFlatDataParser parser = new URIExtractionNamespace.TSVFlatDataParser(
         ImmutableList.of("col1", "col2", "col3"),
         "|",
-        "col2",
+        null, "col2",
         "col3"
     );
     Assert.assertEquals(ImmutableMap.of("B", "C"), parser.getParser().parse("A|B|C"));
   }
 
+  @Test
+  public void testWithListDelimiterTSV()
+  {
+    URIExtractionNamespace.TSVFlatDataParser parser = new URIExtractionNamespace.TSVFlatDataParser(
+        ImmutableList.of("col1", "col2", "col3"),
+        "\\u0001",
+        "\\u0002", "col2",
+        "col3"
+    );
+    Assert.assertEquals(ImmutableMap.of("B", "C"), parser.getParser().parse("A\\u0001B\\u0001C"));
+  }
+
   @Test(expected = IllegalArgumentException.class)
   public void testBadTSV()
   {
     URIExtractionNamespace.TSVFlatDataParser parser = new URIExtractionNamespace.TSVFlatDataParser(
         ImmutableList.of("col1", "col2", "col3fdsfds"),
         ",",
-        "col2",
+        null, "col2",
         "col3"
     );
     Map<String, String> map = parser.getParser().parse("A,B,C");
@@ -147,7 +159,7 @@ public class URIExtractionNamespaceTest
     URIExtractionNamespace.TSVFlatDataParser parser = new URIExtractionNamespace.TSVFlatDataParser(
         ImmutableList.of("col1", "col2", "col3"),
         ",",
-        "col2",
+        null, "col2",
         "col3"
     );
     Map<String, String> map = parser.getParser().parse("A");
@@ -293,7 +305,7 @@ public class URIExtractionNamespaceTest
         ),
         new URIExtractionNamespace.ObjectMapperFlatDataParser(mapper),
         new URIExtractionNamespace.JSONFlatDataParser(mapper, "keyField", "valueField"),
-        new URIExtractionNamespace.TSVFlatDataParser(ImmutableList.of("A", "B"), ",", "A", "B")
+        new URIExtractionNamespace.TSVFlatDataParser(ImmutableList.of("A", "B"), ",", null, "A", "B")
     )) {
       final String str = mapper.writeValueAsString(parser);
       final URIExtractionNamespace.FlatDataParser parser2 = mapper.readValue(
@@ -318,7 +330,7 @@ public class URIExtractionNamespaceTest
         ),
         new URIExtractionNamespace.ObjectMapperFlatDataParser(mapper),
         new URIExtractionNamespace.JSONFlatDataParser(mapper, "keyField", "valueField"),
-        new URIExtractionNamespace.TSVFlatDataParser(ImmutableList.of("A", "B"), ",", "A", "B")
+        new URIExtractionNamespace.TSVFlatDataParser(ImmutableList.of("A", "B"), ",", null, "A", "B")
     )) {
       Assert.assertFalse(parser.toString().contains("@"));
     }