GH-1619: fix Precision loss with SenMLJSON and Old JSON content Format.

leshan-core/src/main/java/org/eclipse/leshan/core/json/jackson/LwM2mJsonJacksonEncoderDecoder.java

@@ -25,6 +25,7 @@
 import org.eclipse.leshan.core.json.LwM2mJsonException;
 import org.eclipse.leshan.core.util.json.JsonException;
 
+import com.fasterxml.jackson.databind.DeserializationFeature;
 import com.fasterxml.jackson.databind.ObjectMapper;
 import com.fasterxml.jackson.databind.cfg.JsonNodeFeature;
 
@@ -33,9 +34,22 @@
  */
 public class LwM2mJsonJacksonEncoderDecoder implements LwM2mJsonDecoder, LwM2mJsonEncoder {
 
-    private static final JsonRootObjectSerDes serDes = new JsonRootObjectSerDes();
-    private static final ObjectMapper mapper = new ObjectMapper()
-            .configure(JsonNodeFeature.STRIP_TRAILING_BIGDECIMAL_ZEROES, false);
+    private final JsonRootObjectSerDes serDes;
+    private final ObjectMapper mapper;
+
+    public LwM2mJsonJacksonEncoderDecoder() {
+        this(new JsonRootObjectSerDes(), null);
+    }
+
+    public LwM2mJsonJacksonEncoderDecoder(JsonRootObjectSerDes serDes, ObjectMapper objectMapper) {
+        this.serDes = serDes;
+        this.mapper = objectMapper == null ? createDefaultObjectMapper() : objectMapper;
+    }
+
+    protected ObjectMapper createDefaultObjectMapper() {
+        return new ObjectMapper().configure(JsonNodeFeature.STRIP_TRAILING_BIGDECIMAL_ZEROES, false)
+                .configure(DeserializationFeature.USE_BIG_DECIMAL_FOR_FLOATS, true);
+    }
 
     @Override
     public String toJsonLwM2m(JsonRootObject jro) throws LwM2mJsonException {

leshan-core/src/main/java/org/eclipse/leshan/senml/json/jackson/SenMLJsonJacksonEncoderDecoder.java

@@ -32,6 +32,7 @@
 import org.eclipse.leshan.senml.SenMLPack;
 import org.eclipse.leshan.senml.SenMLRecord;
 
+import com.fasterxml.jackson.databind.DeserializationFeature;
 import com.fasterxml.jackson.databind.JsonNode;
 import com.fasterxml.jackson.databind.ObjectMapper;
 import com.fasterxml.jackson.databind.cfg.JsonNodeFeature;
@@ -41,8 +42,7 @@
  */
 public class SenMLJsonJacksonEncoderDecoder implements SenMLDecoder, SenMLEncoder {
     private final JacksonJsonSerDes<SenMLRecord> serDes;
-    private static final ObjectMapper mapper = new ObjectMapper()
-            .configure(JsonNodeFeature.STRIP_TRAILING_BIGDECIMAL_ZEROES, false);
+    private final ObjectMapper mapper;
 
     public SenMLJsonJacksonEncoderDecoder() {
         this(false);
@@ -68,7 +68,18 @@ public SenMLJsonJacksonEncoderDecoder(boolean allowNoValue, Base64Decoder base64
     }
 
     public SenMLJsonJacksonEncoderDecoder(JacksonJsonSerDes<SenMLRecord> senMLJSONSerializerDeserializer) {
+        this(senMLJSONSerializerDeserializer, null);
+    }
+
+    public SenMLJsonJacksonEncoderDecoder(JacksonJsonSerDes<SenMLRecord> senMLJSONSerializerDeserializer,
+            ObjectMapper objectMapper) {
         this.serDes = senMLJSONSerializerDeserializer;
+        this.mapper = objectMapper == null ? createDefaultObjectMapper() : objectMapper;
+    }
+
+    protected ObjectMapper createDefaultObjectMapper() {
+        return new ObjectMapper().configure(JsonNodeFeature.STRIP_TRAILING_BIGDECIMAL_ZEROES, false)
+                .configure(DeserializationFeature.USE_BIG_DECIMAL_FOR_FLOATS, true);
     }
 
     @Override

leshan-core/src/test/java/org/eclipse/leshan/core/json/JsonDeserializerTest.java

@@ -47,7 +47,7 @@ public void deserialize_device_object() throws LwM2mJsonException {
         b.append("{\"n\":\"9\",\"v\":100},");
         b.append("{\"n\":\"10\",\"v\":15},");
         b.append("{\"n\":\"11/0\",\"v\":0},");
-        b.append("{\"n\":\"13\",\"v\":1.367491215E9},");
+        b.append("{\"n\":\"13\",\"v\":1367491215},");
         b.append("{\"n\":\"14\",\"sv\":\"+02:00\"},");
         b.append("{\"n\":\"15\",\"sv\":\"U\"}]}");
 

leshan-core/src/test/java/org/eclipse/leshan/core/node/codec/LwM2mNodeDecoderEncoderTest.java

@@ -0,0 +1,68 @@
+/*******************************************************************************
+ * Copyright (c) 2024 Sierra Wireless and others.
+ *
+ * All rights reserved. This program and the accompanying materials
+ * are made available under the terms of the Eclipse Public License v2.0
+ * and Eclipse Distribution License v1.0 which accompany this distribution.
+ *
+ * The Eclipse Public License is available at
+ *    http://www.eclipse.org/legal/epl-v20.html
+ * and the Eclipse Distribution License is available at
+ *    http://www.eclipse.org/org/documents/edl-v10.html.
+ *
+ * Contributors:
+ *     Sierra Wireless - initial API and implementation
+ *******************************************************************************/
+package org.eclipse.leshan.core.node.codec;
+
+import static org.junit.jupiter.api.Assertions.assertEquals;
+import static org.junit.jupiter.params.provider.Arguments.arguments;
+
+import java.time.Instant;
+import java.util.Arrays;
+import java.util.List;
+import java.util.stream.Stream;
+
+import org.eclipse.leshan.core.model.LwM2mModel;
+import org.eclipse.leshan.core.model.StaticModel;
+import org.eclipse.leshan.core.node.LwM2mPath;
+import org.eclipse.leshan.core.node.LwM2mSingleResource;
+import org.eclipse.leshan.core.node.TimestampedLwM2mNode;
+import org.eclipse.leshan.core.request.ContentFormat;
+import org.eclipse.leshan.core.util.TestObjectLoader;
+import org.junit.jupiter.params.ParameterizedTest;
+import org.junit.jupiter.params.provider.MethodSource;
+
+public class LwM2mNodeDecoderEncoderTest {
+
+    private final LwM2mDecoder decoder = new DefaultLwM2mDecoder();
+    private final LwM2mEncoder encoder = new DefaultLwM2mEncoder();
+    private final LwM2mModel model = new StaticModel(TestObjectLoader.loadAllDefault());
+
+    static Stream<org.junit.jupiter.params.provider.Arguments> contentFormats() {
+        return Stream.of(//
+                arguments(ContentFormat.JSON), //
+                arguments(ContentFormat.SENML_JSON), //
+                arguments(ContentFormat.SENML_CBOR));
+    }
+
+    @ParameterizedTest(name = "{0}")
+    @MethodSource("contentFormats")
+    public void encode_decode_timestamped_value(ContentFormat format) {
+
+        // resource used for test
+        LwM2mPath resourcePath = new LwM2mPath("3442/0/120");
+        Instant t1 = Instant.parse("2024-05-23T21:55:00.556635828Z");
+        LwM2mSingleResource resource = LwM2mSingleResource.newIntegerResource(resourcePath.getResourceId(), 3600);
+        List<TimestampedLwM2mNode> timestampedData = Arrays.asList(new TimestampedLwM2mNode(t1, resource));
+
+        // try to encode then to decode and compare result
+        byte[] encodedTimestampedData = encoder.encodeTimestampedData(timestampedData, format, resourcePath, model);
+
+        List<TimestampedLwM2mNode> decodeTimestampedData = decoder.decodeTimestampedData(encodedTimestampedData, format,
+                resourcePath, model);
+
+        assertEquals(timestampedData, decodeTimestampedData);
+    }
+
+}