update ScalarFunction annotation from name to names to support function alias. (#8252)

xiangfu0 · web-flow · commit d999aeca31ad · 2022-02-26T03:01:11.000-08:00
diff --git a/pinot-common/src/main/java/org/apache/pinot/common/function/FunctionRegistry.java b/pinot-common/src/main/java/org/apache/pinot/common/function/FunctionRegistry.java
@@ -61,8 +61,12 @@ private FunctionRegistry() {
     for (Method method : methodSet) {
       ScalarFunction scalarFunction = method.getAnnotation(ScalarFunction.class);
       if (scalarFunction.enabled()) {
-        if (!scalarFunction.name().isEmpty()) {
-          FunctionRegistry.registerFunction(scalarFunction.name(), method);
+        // Annotated function names
+        String[] scalarFunctionNames = scalarFunction.names();
+        if (scalarFunctionNames.length > 0) {
+          for (String name : scalarFunctionNames) {
+            FunctionRegistry.registerFunction(name, method);
+          }
         } else {
           FunctionRegistry.registerFunction(method);
         }
diff --git a/pinot-common/src/test/java/org/apache/pinot/common/function/FunctionDefinitionRegistryTest.java b/pinot-common/src/test/java/org/apache/pinot/common/function/FunctionDefinitionRegistryTest.java
@@ -19,9 +19,12 @@
 package org.apache.pinot.common.function;
 
 import org.apache.pinot.segment.spi.AggregationFunctionType;
+import org.apache.pinot.spi.annotations.ScalarFunction;
 import org.testng.annotations.Test;
 
 import static org.testng.Assert.assertFalse;
+import static org.testng.Assert.assertNotNull;
+import static org.testng.Assert.assertNull;
 import static org.testng.Assert.assertTrue;
 
 
@@ -55,4 +58,18 @@ public void testIsTransformFunc() {
     assertTrue(TransformFunctionType.isTransformFunction("STASTEXT"));
     assertFalse(TransformFunctionType.isTransformFunction("foo_bar"));
   }
+
+  @ScalarFunction(names = {"testFunc1", "testFunc2"})
+  public static String testScalarFunction(long randomArg1, String randomArg2) {
+    return null;
+  }
+
+  @Test
+  public void testScalarFunctionNames() {
+    assertNotNull(FunctionRegistry.getFunctionInfo("testFunc1", 2));
+    assertNotNull(FunctionRegistry.getFunctionInfo("testFunc2", 2));
+    assertNull(FunctionRegistry.getFunctionInfo("testScalarFunction", 2));
+    assertNull(FunctionRegistry.getFunctionInfo("testFunc1", 1));
+    assertNull(FunctionRegistry.getFunctionInfo("testFunc2", 1));
+  }
 }
diff --git a/pinot-spi/src/main/java/org/apache/pinot/spi/annotations/ScalarFunction.java b/pinot-spi/src/main/java/org/apache/pinot/spi/annotations/ScalarFunction.java
@@ -46,5 +46,7 @@
 
   boolean enabled() default true;
 
-  String name() default "";
+  // If empty, FunctionsRegistry registers the method name as function name;
+  // If not empty, FunctionsRegistry only registers the function names specified here, the method name is ignored.
+  String[] names() default {};
 }

Original file line number	Diff line number	Diff line change
`@@ -46,5 +46,7 @@`
`46`	`46`
`47`	`47`	`boolean enabled() default true;`
`48`	`48`
`49`		`- String name() default "";`
	`49`	`+ // If empty, FunctionsRegistry registers the method name as function name;`
	`50`	`+ // If not empty, FunctionsRegistry only registers the function names specified here, the method name is ignored.`
	`51`	`+ String[] names() default {};`
`50`	`52`	`}`