Merge pull request #13120 from irynamatveieva/cf-expression

Added custom functions to the math node

application/src/main/java/org/thingsboard/server/service/cf/ctx/state/CalculatedFieldCtx.java

@@ -18,8 +18,6 @@ package org.thingsboard.server.service.cf.ctx.state;
 import lombok.Data;
 import net.objecthunter.exp4j.Expression;
 import net.objecthunter.exp4j.ExpressionBuilder;
-import net.objecthunter.exp4j.function.Function;
-import net.objecthunter.exp4j.function.Functions;
 import org.mvel2.MVEL;
 import org.thingsboard.script.api.tbel.TbelInvokeService;
 import org.thingsboard.server.common.data.AttributeScope;
@@ -46,6 +44,8 @@ import java.util.HashMap;
 import java.util.List;
 import java.util.Map;
 
+import static org.thingsboard.common.util.ExpressionFunctionsUtil.userDefinedFunctions;
+
 @Data
 public class CalculatedFieldCtx {
 
@@ -282,50 +282,4 @@ public class CalculatedFieldCtx {
         return "Failed to init CF state. State size exceeds limit of " + (maxStateSize / 1024) + "Kb!";
     }
 
-    private static final List<Function> userDefinedFunctions = List.of(
-            new Function("ln") {
-                @Override
-                public double apply(double... args) {
-                    return Math.log(args[0]);
-                }
-            },
-            new Function("lg") {
-                @Override
-                public double apply(double... args) {
-                    return Math.log10(args[0]);
-                }
-            },
-            new Function("logab", 2) {
-                @Override
-                public double apply(double... args) {
-                    return Math.log(args[1]) / Math.log(args[0]);
-                }
-            },
-
-            // Manually listing built-in functions to avoid inefficient equals-based lookup in Functions.getBuiltinFunction during each evaluation.
-            Functions.getBuiltinFunction("sin"),
-            Functions.getBuiltinFunction("cos"),
-            Functions.getBuiltinFunction("tan"),
-            Functions.getBuiltinFunction("cot"),
-            Functions.getBuiltinFunction("log"),
-            Functions.getBuiltinFunction("log2"),
-            Functions.getBuiltinFunction("log10"),
-            Functions.getBuiltinFunction("log1p"),
-            Functions.getBuiltinFunction("abs"),
-            Functions.getBuiltinFunction("acos"),
-            Functions.getBuiltinFunction("asin"),
-            Functions.getBuiltinFunction("atan"),
-            Functions.getBuiltinFunction("cbrt"),
-            Functions.getBuiltinFunction("floor"),
-            Functions.getBuiltinFunction("sinh"),
-            Functions.getBuiltinFunction("sqrt"),
-            Functions.getBuiltinFunction("tanh"),
-            Functions.getBuiltinFunction("cosh"),
-            Functions.getBuiltinFunction("ceil"),
-            Functions.getBuiltinFunction("pow"),
-            Functions.getBuiltinFunction("exp"),
-            Functions.getBuiltinFunction("expm1"),
-            Functions.getBuiltinFunction("signum")
-    );
-
 }

common/util/pom.xml

@@ -111,6 +111,11 @@
             <groupId>org.locationtech.jts</groupId>
             <artifactId>jts-core</artifactId>
         </dependency>
+        <dependency>
+            <groupId>net.objecthunter</groupId>
+            <artifactId>exp4j</artifactId>
+            <version>${exp4j.version}</version>
+        </dependency>
     </dependencies>
 
     <build>

common/util/src/main/java/org/thingsboard/common/util/ExpressionFunctionsUtil.java

@@ -0,0 +1,78 @@
+/**
+ * Copyright © 2016-2025 The Thingsboard Authors
+ *
+ * Licensed 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.thingsboard.common.util;
+
+import net.objecthunter.exp4j.function.Function;
+import net.objecthunter.exp4j.function.Functions;
+
+import java.util.ArrayList;
+import java.util.List;
+
+public class ExpressionFunctionsUtil {
+
+    public static final List<Function> userDefinedFunctions = new ArrayList<>();
+
+    static {
+        userDefinedFunctions.add(
+                new Function("ln") {
+                    @Override
+                    public double apply(double... args) {
+                        return Math.log(args[0]);
+                    }
+                }
+        );
+        userDefinedFunctions.add(
+                new Function("lg") {
+                    @Override
+                    public double apply(double... args) {
+                        return Math.log10(args[0]);
+                    }
+                }
+        );
+        userDefinedFunctions.add(
+                new Function("logab", 2) {
+                    @Override
+                    public double apply(double... args) {
+                        return Math.log(args[1]) / Math.log(args[0]);
+                    }
+                }
+        );
+        userDefinedFunctions.add(Functions.getBuiltinFunction("sin"));
+        userDefinedFunctions.add(Functions.getBuiltinFunction("cos"));
+        userDefinedFunctions.add(Functions.getBuiltinFunction("tan"));
+        userDefinedFunctions.add(Functions.getBuiltinFunction("cot"));
+        userDefinedFunctions.add(Functions.getBuiltinFunction("log"));
+        userDefinedFunctions.add(Functions.getBuiltinFunction("log2"));
+        userDefinedFunctions.add(Functions.getBuiltinFunction("log10"));
+        userDefinedFunctions.add(Functions.getBuiltinFunction("log1p"));
+        userDefinedFunctions.add(Functions.getBuiltinFunction("abs"));
+        userDefinedFunctions.add(Functions.getBuiltinFunction("acos"));
+        userDefinedFunctions.add(Functions.getBuiltinFunction("asin"));
+        userDefinedFunctions.add(Functions.getBuiltinFunction("atan"));
+        userDefinedFunctions.add(Functions.getBuiltinFunction("cbrt"));
+        userDefinedFunctions.add(Functions.getBuiltinFunction("floor"));
+        userDefinedFunctions.add(Functions.getBuiltinFunction("sinh"));
+        userDefinedFunctions.add(Functions.getBuiltinFunction("sqrt"));
+        userDefinedFunctions.add(Functions.getBuiltinFunction("tanh"));
+        userDefinedFunctions.add(Functions.getBuiltinFunction("cosh"));
+        userDefinedFunctions.add(Functions.getBuiltinFunction("ceil"));
+        userDefinedFunctions.add(Functions.getBuiltinFunction("pow"));
+        userDefinedFunctions.add(Functions.getBuiltinFunction("exp"));
+        userDefinedFunctions.add(Functions.getBuiltinFunction("expm1"));
+        userDefinedFunctions.add(Functions.getBuiltinFunction("signum"));
+    }
+
+}

rule-engine/rule-engine-components/src/main/java/org/thingsboard/rule/engine/math/TbMathNode.java

@@ -53,6 +53,7 @@ import java.util.function.BiFunction;
 import java.util.function.Function;
 import java.util.stream.Collectors;
 
+import static org.thingsboard.common.util.ExpressionFunctionsUtil.userDefinedFunctions;
 import static org.thingsboard.rule.engine.math.TbMathArgumentType.CONSTANT;
 
 @SuppressWarnings("UnstableApiUsage")
@@ -310,6 +311,7 @@ public class TbMathNode implements TbNode {
                 var expr = customExpression.get();
                 if (expr == null) {
                     expr = new ExpressionBuilder(config.getCustomFunction())
+                            .functions(userDefinedFunctions)
                             .implicitMultiplication(true)
                             .variables(config.getArguments().stream().map(TbMathArgument::getName).collect(Collectors.toSet()))
                             .build();

rule-engine/rule-engine-components/src/test/java/org/thingsboard/rule/engine/math/TbMathNodeTest.java

@@ -56,6 +56,8 @@ import org.thingsboard.server.common.msg.TbMsgMetaData;
 import org.thingsboard.server.dao.attributes.AttributesService;
 import org.thingsboard.server.dao.timeseries.TimeseriesService;
 
+import java.math.BigDecimal;
+import java.math.RoundingMode;
 import java.util.Arrays;
 import java.util.List;
 import java.util.Optional;
@@ -848,6 +850,42 @@ public class TbMathNodeTest {
         verify(ctx, never()).tellFailure(any(), any());
     }
 
+    @ParameterizedTest
+    @MethodSource
+    public void testCustomFunctions(String customFunction, double result) {
+        var node = initNodeWithCustomFunction(customFunction,
+                new TbMathResult(TbMathArgumentType.MESSAGE_BODY, "result", 2, false, false, null),
+                new TbMathArgument("a", TbMathArgumentType.MESSAGE_BODY, "argumentA"),
+                new TbMathArgument("b", TbMathArgumentType.MESSAGE_BODY, "argumentB")
+        );
+
+        TbMsg msg = TbMsg.newMsg()
+                .type(TbMsgType.POST_TELEMETRY_REQUEST)
+                .originator(originator)
+                .metaData(TbMsgMetaData.EMPTY)
+                .data("{\"argumentA\":2,\"argumentB\":5}")
+                .build();
+
+        node.onMsg(ctx, msg);
+
+        ArgumentCaptor<TbMsg> msgCaptor = ArgumentCaptor.forClass(TbMsg.class);
+        verify(ctx, timeout(TIMEOUT)).tellSuccess(msgCaptor.capture());
+        TbMsg outMsg = msgCaptor.getValue();
+        assertThat(outMsg).isNotNull();
+        assertThat(outMsg.getData()).isNotNull();
+        var resultJson = JacksonUtil.toJsonNode(outMsg.getData());
+        assertThat(resultJson.has("result")).isTrue();
+        assertThat(resultJson.get("result").asDouble()).isEqualTo(new BigDecimal(result).setScale(2, RoundingMode.HALF_UP).doubleValue());
+    }
+
+    private static Stream<Arguments> testCustomFunctions() {
+        return Stream.of(
+                Arguments.of("ln(a)", Math.log(2)),
+                Arguments.of("lg(a)", Math.log10(2)),
+                Arguments.of("logab(a, b)", Math.log(5) / Math.log(2))
+        );
+    }
+
     static class RuleDispatcherExecutor extends AbstractListeningExecutor {
         @Override
         protected int getThreadPollSize() {