[INLONG-11236][SDK] Transform SQL supports FIND_IN_SET function

inlong-sdk/transform-sdk/src/main/java/org/apache/inlong/sdk/transform/process/function/FindInSetFunction.java

@@ -0,0 +1,66 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements. See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to You under the Apache License, Version 2.0
+ * (the "License"); you may not use this file except in compliance with
+ * the License. You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.apache.inlong.sdk.transform.process.function;
+
+import org.apache.inlong.sdk.transform.decode.SourceData;
+import org.apache.inlong.sdk.transform.process.Context;
+import org.apache.inlong.sdk.transform.process.operator.OperatorTools;
+import org.apache.inlong.sdk.transform.process.parser.ValueParser;
+
+import net.sf.jsqlparser.expression.Function;
+
+/**
+ * LengthFunction  -> FindInSetFunction(str,strList)
+ * description:
+ * - return a value in the range of 1 to N if the string str is in the string list strList consisting of N substrings.
+ * - return 0 if str is not in strList or if strList is the empty string.
+ * - return NULL if either argument is NULL.
+ * Note: `strList` is a string composed of substrings separated by ',' characters. This function does not work properly
+ * if the first argument contains a comma (,) character.
+ */
+@TransformFunction(names = {"find_in_set"})
+public class FindInSetFunction implements ValueParser {
+
+    private final ValueParser strParser;
+    private final ValueParser strListParser;
+
+    public FindInSetFunction(Function expr) {
+        strParser = OperatorTools.buildParser(expr.getParameters().getExpressions().get(0));
+        strListParser = OperatorTools.buildParser(expr.getParameters().getExpressions().get(1));
+    }
+
+    @Override
+    public Object parse(SourceData sourceData, int rowIndex, Context context) {
+        Object strObj = strParser.parse(sourceData, rowIndex, context);
+        Object strListObj = strListParser.parse(sourceData, rowIndex, context);
+        if (strObj == null || strListObj == null) {
+            return null;
+        }
+        String str = OperatorTools.parseString(strObj);
+        String strList = OperatorTools.parseString(strListObj);
+        if (!strList.isEmpty()) {
+            String[] strArray = strList.split(",");
+            for (int i = 0; i < strArray.length; i++) {
+                if (str.equals(strArray[i])) {
+                    return i + 1;
+                }
+            }
+        }
+        return 0;
+    }
+}

inlong-sdk/transform-sdk/src/test/java/org/apache/inlong/sdk/transform/process/function/TestFindInSetFunction.java

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+/*
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements. See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to You under the Apache License, Version 2.0
+ * (the "License"); you may not use this file except in compliance with
+ * the License. You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.apache.inlong.sdk.transform.process.function;
+
+import org.apache.inlong.sdk.transform.decode.SourceDecoderFactory;
+import org.apache.inlong.sdk.transform.encode.SinkEncoderFactory;
+import org.apache.inlong.sdk.transform.pojo.TransformConfig;
+import org.apache.inlong.sdk.transform.process.TransformProcessor;
+import org.apache.inlong.sdk.transform.process.function.string.AbstractFunctionStringTestBase;
+
+import org.junit.Assert;
+import org.junit.Test;
+
+import java.util.HashMap;
+import java.util.List;
+
+public class TestFindInSetFunction extends AbstractFunctionStringTestBase {
+
+    @Test
+    public void testFindInSetFunction() throws Exception {
+        String transformSql = null, data = null;
+        TransformConfig config = null;
+        TransformProcessor<String, String> processor = null;
+        List<String> output = null;
+
+        transformSql = "select FIND_IN_SET(string1,string2) from source";
+        config = new TransformConfig(transformSql);
+        processor = TransformProcessor
+                .create(config, SourceDecoderFactory.createCsvDecoder(csvSource),
+                        SinkEncoderFactory.createKvEncoder(kvSink));
+        // case1: FIND_IN_SET('b','a,b,b,c,d')
+        data = "b|a,b,b,c,d|cloud|5|3|3";
+        output = processor.transform(data, new HashMap<>());
+        Assert.assertEquals(1, output.size());
+        Assert.assertEquals("result=2", output.get(0));
+
+        // case2: FIND_IN_SET('','a,,b,c,d');
+        data = "|a,,b,c,d|cloud|5|3|3";
+        output = processor.transform(data, new HashMap<>());
+        Assert.assertEquals(1, output.size());
+        Assert.assertEquals("result=2", output.get(0));
+
+        // case3: FIND_IN_SET(',','a,,b,c,d');
+        data = ",|a,,b,c,d|cloud|5|3|3";
+        output = processor.transform(data, new HashMap<>());
+        Assert.assertEquals(1, output.size());
+        Assert.assertEquals("result=0", output.get(0));
+
+        // case4: FIND_IN_SET('',''); This situation returns 0
+        data = "||cloud|5|3|3";
+        output = processor.transform(data, new HashMap<>());
+        Assert.assertEquals(1, output.size());
+        Assert.assertEquals("result=0", output.get(0));
+    }
+}