adding AliasExprMacro

apache · Oct 5, 2023 · 7e02460 · 7e02460
1 parent 8e24394
commit 7e02460
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Showing 5 changed files with 56 additions and 36 deletions.
diff --git a/...druid/query/aggregation/datasketches/tuple/sql/ArrayOfDoublesSketchSqlAggregatorTest.java b/...druid/query/aggregation/datasketches/tuple/sql/ArrayOfDoublesSketchSqlAggregatorTest.java
@@ -325,7 +325,11 @@ public void testMetricsSumEstimateIntersect()
                   .build()
         );
     testQuery(sql, expectedQueries, expectedResults);
-    testQuery(sql.replaceAll("COMPLEX_DECODE_BASE64", "DECODE_BASE64_COMPLEX"), expectedQueries, expectedResults);
+    testQuery(
+        StringUtils.replace(sql, "COMPLEX_DECODE_BASE64", "DECODE_BASE64_COMPLEX"),
+        expectedQueries,
+        expectedResults
+    );
   }
 
   @Test

diff --git a/processing/src/main/java/org/apache/druid/math/expr/BuiltInExprMacros.java b/processing/src/main/java/org/apache/druid/math/expr/BuiltInExprMacros.java
@@ -25,28 +25,26 @@
 import javax.annotation.Nullable;
 import java.util.Collections;
 import java.util.List;
-import java.util.Optional;
 import java.util.stream.Collectors;
 
 public class BuiltInExprMacros
 {
   public static class ComplexDecodeBase64ExprMacro implements ExprMacroTable.ExprMacro
   {
     public static final String NAME = "complex_decode_base64";
-    public static final String ALIAS_NAME = "decode_base64_complex";
+    public static final String ALIAS = "decode_base64_complex";
 
+    /**
+     * use name() in closure scope to allow Alias macro to override it with alias.
+     *
+     * @return String
+     */
     @Override
     public String name()
     {
       return NAME;
     }
 
-    @Override
-    public Optional<String> alias()
-    {
-      return Optional.of(ALIAS_NAME);
-    }
-
     @Override
     public Expr apply(List<Expr> args)
     {
@@ -60,7 +58,7 @@ final class ComplexDecodeBase64Expression extends ExprMacroTable.BaseScalarMacro
 
       public ComplexDecodeBase64Expression(List<Expr> args)
       {
-        super(NAME, args);
+        super(name(), args);
         validationHelperCheckArgumentCount(args, 2);
         final Expr arg0 = args.get(0);
 
@@ -156,7 +154,6 @@ public Object getLiteralValue()
 
   public static class StringDecodeBase64UTFExprMacro implements ExprMacroTable.ExprMacro
   {
-
     public static final String NAME = "decode_base64_utf8";
 
     @Override
@@ -166,6 +163,11 @@ public Expr apply(List<Expr> args)
       return new StringDecodeBase64UTFExpression(args.get(0));
     }
 
+    /**
+     * use name() in closure scope to allow Alias macro to override it with alias.
+     *
+     * @return String
+     */
     @Override
     public String name()
     {
@@ -176,7 +178,7 @@ final class StringDecodeBase64UTFExpression extends ExprMacroTable.BaseScalarUni
     {
       public StringDecodeBase64UTFExpression(Expr arg)
       {
-        super(NAME, arg);
+        super(name(), arg);
       }
 
       @Override
@@ -222,4 +224,31 @@ public Object getLiteralValue()
       }
     }
   }
+
+  /***
+   * Alias Expression macro to create an alias and delegate operations to the same base macro
+   */
+  public static class AliasExprMacro implements ExprMacroTable.ExprMacro
+  {
+    private final ExprMacroTable.ExprMacro exprMacro;
+    private final String alias;
+
+    public AliasExprMacro(final ExprMacroTable.ExprMacro baseExprMacro, final String alias)
+    {
+      this.exprMacro = baseExprMacro;
+      this.alias = alias;
+    }
+
+    @Override
+    public Expr apply(List<Expr> args)
+    {
+      return exprMacro.apply(args);
+    }
+
+    @Override
+    public String name()
+    {
+      return alias;
+    }
+  }
 }
diff --git a/processing/src/main/java/org/apache/druid/math/expr/ExprMacroTable.java b/processing/src/main/java/org/apache/druid/math/expr/ExprMacroTable.java
@@ -33,6 +33,7 @@
 import java.util.Map;
 import java.util.Objects;
 import java.util.Set;
+import java.util.stream.Collectors;
 
 /**
  * Mechanism by which Druid expressions can define new functions for the Druid expression language. When
@@ -42,8 +43,13 @@
  */
 public class ExprMacroTable
 {
+  private static final BuiltInExprMacros.ComplexDecodeBase64ExprMacro COMPLEX_DECODE_BASE_64_EXPR_MACRO = new BuiltInExprMacros.ComplexDecodeBase64ExprMacro();
   private static final List<ExprMacro> BUILT_IN = ImmutableList.of(
-      new BuiltInExprMacros.ComplexDecodeBase64ExprMacro(),
+      COMPLEX_DECODE_BASE_64_EXPR_MACRO,
+      new BuiltInExprMacros.AliasExprMacro(
+          COMPLEX_DECODE_BASE_64_EXPR_MACRO,
+          BuiltInExprMacros.ComplexDecodeBase64ExprMacro.ALIAS
+      ),
       new BuiltInExprMacros.StringDecodeBase64UTFExprMacro()
   );
   private static final ExprMacroTable NIL = new ExprMacroTable(Collections.emptyList());
@@ -52,19 +58,9 @@ public class ExprMacroTable
 
   public ExprMacroTable(final List<ExprMacro> macros)
   {
-    this.macroMap = Maps.newHashMapWithExpectedSize(BUILT_IN.size() + 1 + macros.size());
-    BUILT_IN.forEach(m -> {
-      macroMap.put(StringUtils.toLowerCase(m.name()), m);
-      if (m.alias().isPresent()) {
-        macroMap.put(StringUtils.toLowerCase(m.alias().get()), m);
-      }
-    });
-    for (ExprMacro macro : macros) {
-      macroMap.put(StringUtils.toLowerCase(macro.name()), macro);
-      if (macro.alias().isPresent()) {
-        macroMap.put(StringUtils.toLowerCase(macro.alias().get()), macro);
-      }
-    }
+    this.macroMap = Maps.newHashMapWithExpectedSize(BUILT_IN.size() + macros.size());
+    macroMap.putAll(BUILT_IN.stream().collect(Collectors.toMap(m -> StringUtils.toLowerCase(m.name()), m -> m)));
+    macroMap.putAll(macros.stream().collect(Collectors.toMap(m -> StringUtils.toLowerCase(m.name()), m -> m)));
   }
 
   public static ExprMacroTable nil()

diff --git a/processing/src/main/java/org/apache/druid/math/expr/NamedFunction.java b/processing/src/main/java/org/apache/druid/math/expr/NamedFunction.java
@@ -23,7 +23,6 @@
 
 import java.util.Arrays;
 import java.util.List;
-import java.util.Optional;
 
 /**
  * Common stuff for "named" functions of "functional" expressions, such as {@link FunctionExpr},
@@ -39,14 +38,6 @@ public interface NamedFunction
    */
   String name();
 
-  /**
-   * Alias of the function
-   */
-  default Optional<String> alias()
-  {
-    return Optional.empty();
-  }
-
   /**
    * Helper method for creating a {@link ExpressionValidationException} with the specified reason
    */

diff --git a/sql/src/main/java/org/apache/druid/sql/calcite/planner/DruidOperatorTable.java b/sql/src/main/java/org/apache/druid/sql/calcite/planner/DruidOperatorTable.java
@@ -236,7 +236,7 @@ public class DruidOperatorTable implements SqlOperatorTable
                    .add(COMPLEX_DECODE_OPERATOR_CONVERSIONS)
                    .add(new AliasedOperatorConversion(
                        COMPLEX_DECODE_OPERATOR_CONVERSIONS,
-                       BuiltInExprMacros.ComplexDecodeBase64ExprMacro.ALIAS_NAME
+                       BuiltInExprMacros.ComplexDecodeBase64ExprMacro.ALIAS
                    ))
                    .add(new DecodeBase64UTFOperatorConversion())
                    .build();