Prevent modifications of JsonUtil's JSON_FACTORY

`JsonFactory` is mutable.

Author: findepi

core/trino-main/src/main/java/io/trino/operator/scalar/JsonToArrayCast.java

@@ -13,8 +13,10 @@
  */
 package io.trino.operator.scalar;
 
+import com.fasterxml.jackson.core.JsonFactory;
 import com.fasterxml.jackson.core.JsonParser;
 import com.fasterxml.jackson.core.JsonToken;
+import com.fasterxml.jackson.databind.ObjectMapper;
 import com.google.common.collect.ImmutableList;
 import io.airlift.slice.Slice;
 import io.trino.annotation.UsedByGeneratedCode;
@@ -41,8 +43,8 @@
 import static io.trino.spi.type.TypeSignature.arrayType;
 import static io.trino.type.JsonType.JSON;
 import static io.trino.util.Failures.checkCondition;
-import static io.trino.util.JsonUtil.JSON_FACTORY;
 import static io.trino.util.JsonUtil.canCastFromJson;
+import static io.trino.util.JsonUtil.createJsonFactory;
 import static io.trino.util.JsonUtil.createJsonParser;
 import static io.trino.util.JsonUtil.truncateIfNecessaryForErrorMessage;
 import static io.trino.util.Reflection.methodHandle;
@@ -54,6 +56,13 @@ public class JsonToArrayCast
     public static final JsonToArrayCast JSON_TO_ARRAY = new JsonToArrayCast();
     private static final MethodHandle METHOD_HANDLE = methodHandle(JsonToArrayCast.class, "toArray", ArrayType.class, BlockBuilderAppender.class, ConnectorSession.class, Slice.class);
 
+    private static final JsonFactory JSON_FACTORY = createJsonFactory();
+
+    static {
+        // Changes factory. Necessary for JsonParser.readValueAsTree to work.
+        new ObjectMapper(JSON_FACTORY);
+    }
+
     private JsonToArrayCast()
     {
         super(FunctionMetadata.scalarBuilder()

core/trino-main/src/main/java/io/trino/operator/scalar/JsonToMapCast.java

@@ -13,8 +13,10 @@
  */
 package io.trino.operator.scalar;
 
+import com.fasterxml.jackson.core.JsonFactory;
 import com.fasterxml.jackson.core.JsonParser;
 import com.fasterxml.jackson.core.JsonToken;
+import com.fasterxml.jackson.databind.ObjectMapper;
 import com.google.common.collect.ImmutableList;
 import io.airlift.slice.Slice;
 import io.trino.annotation.UsedByGeneratedCode;
@@ -43,8 +45,8 @@
 import static io.trino.type.JsonType.JSON;
 import static io.trino.util.Failures.checkCondition;
 import static io.trino.util.JsonUtil.BlockBuilderAppender.createBlockBuilderAppender;
-import static io.trino.util.JsonUtil.JSON_FACTORY;
 import static io.trino.util.JsonUtil.canCastFromJson;
+import static io.trino.util.JsonUtil.createJsonFactory;
 import static io.trino.util.JsonUtil.createJsonParser;
 import static io.trino.util.JsonUtil.truncateIfNecessaryForErrorMessage;
 import static io.trino.util.Reflection.methodHandle;
@@ -56,6 +58,13 @@ public class JsonToMapCast
     public static final JsonToMapCast JSON_TO_MAP = new JsonToMapCast();
     private static final MethodHandle METHOD_HANDLE = methodHandle(JsonToMapCast.class, "toMap", MapType.class, BlockBuilderAppender.class, ConnectorSession.class, Slice.class);
 
+    private static final JsonFactory JSON_FACTORY = createJsonFactory();
+
+    static {
+        // Changes factory. Necessary for JsonParser.readValueAsTree to work.
+        new ObjectMapper(JSON_FACTORY);
+    }
+
     private JsonToMapCast()
     {
         super(FunctionMetadata.scalarBuilder()

core/trino-main/src/main/java/io/trino/operator/scalar/JsonToRowCast.java

@@ -13,8 +13,10 @@
  */
 package io.trino.operator.scalar;
 
+import com.fasterxml.jackson.core.JsonFactory;
 import com.fasterxml.jackson.core.JsonParser;
 import com.fasterxml.jackson.core.JsonToken;
+import com.fasterxml.jackson.databind.ObjectMapper;
 import com.google.common.collect.ImmutableList;
 import io.airlift.slice.Slice;
 import io.trino.annotation.UsedByGeneratedCode;
@@ -41,8 +43,8 @@
 import static io.trino.type.JsonType.JSON;
 import static io.trino.util.Failures.checkCondition;
 import static io.trino.util.JsonUtil.BlockBuilderAppender.createBlockBuilderAppender;
-import static io.trino.util.JsonUtil.JSON_FACTORY;
 import static io.trino.util.JsonUtil.canCastFromJson;
+import static io.trino.util.JsonUtil.createJsonFactory;
 import static io.trino.util.JsonUtil.createJsonParser;
 import static io.trino.util.JsonUtil.truncateIfNecessaryForErrorMessage;
 import static io.trino.util.Reflection.methodHandle;
@@ -54,6 +56,13 @@ public class JsonToRowCast
     public static final JsonToRowCast JSON_TO_ROW = new JsonToRowCast();
     private static final MethodHandle METHOD_HANDLE = methodHandle(JsonToRowCast.class, "toRow", RowType.class, BlockBuilderAppender.class, ConnectorSession.class, Slice.class);
 
+    private static final JsonFactory JSON_FACTORY = createJsonFactory();
+
+    static {
+        // Changes factory. Necessary for JsonParser.readValueAsTree to work.
+        new ObjectMapper(JSON_FACTORY);
+    }
+
     private JsonToRowCast()
     {
         super(FunctionMetadata.scalarBuilder()

core/trino-main/src/main/java/io/trino/operator/scalar/timestamp/TimestampToJsonCast.java

@@ -13,6 +13,7 @@
  */
 package io.trino.operator.scalar.timestamp;
 
+import com.fasterxml.jackson.core.JsonFactory;
 import com.fasterxml.jackson.core.JsonGenerator;
 import io.airlift.slice.DynamicSliceOutput;
 import io.airlift.slice.Slice;
@@ -32,7 +33,7 @@
 import static io.trino.spi.function.OperatorType.CAST;
 import static io.trino.spi.type.StandardTypes.JSON;
 import static io.trino.type.DateTimes.formatTimestamp;
-import static io.trino.util.JsonUtil.JSON_FACTORY;
+import static io.trino.util.JsonUtil.createJsonFactory;
 import static io.trino.util.JsonUtil.createJsonGenerator;
 import static java.lang.String.format;
 import static java.time.ZoneOffset.UTC;
@@ -41,6 +42,7 @@
 public final class TimestampToJsonCast
 {
     private static final DateTimeFormatter TIMESTAMP_FORMATTER = DateTimeFormatter.ofPattern("uuuu-MM-dd HH:mm:ss");
+    private static final JsonFactory JSON_FACTORY = createJsonFactory();
 
     private TimestampToJsonCast() {}
 

core/trino-main/src/main/java/io/trino/util/JsonUtil.java

@@ -104,15 +104,19 @@ public final class JsonUtil
 {
     private JsonUtil() {}
 
-    public static final JsonFactory JSON_FACTORY = new JsonFactoryBuilder().disable(CANONICALIZE_FIELD_NAMES).build();
-
     // This object mapper is constructed without .configure(ORDER_MAP_ENTRIES_BY_KEYS, true) because
     // `OBJECT_MAPPER.writeValueAsString(parser.readValueAsTree());` preserves input order.
     // Be aware. Using it arbitrarily can produce invalid json (ordered by key is required in Trino).
-    private static final ObjectMapper OBJECT_MAPPED_UNORDERED = new ObjectMapper(JSON_FACTORY);
+    private static final ObjectMapper OBJECT_MAPPED_UNORDERED = new ObjectMapper(createJsonFactory());
 
     private static final int MAX_JSON_LENGTH_IN_ERROR_MESSAGE = 10_000;
 
+    // Note: JsonFactory is mutable, instances cannot be shared openly.
+    public static JsonFactory createJsonFactory()
+    {
+        return new JsonFactoryBuilder().disable(CANONICALIZE_FIELD_NAMES).build();
+    }
+
     public static JsonParser createJsonParser(JsonFactory factory, Slice json)
             throws IOException
     {