[Feature][Zeta] add from_unixtime function

docs/en/transform-v2/sql-functions.md

@@ -848,6 +848,30 @@ Example:
 
 YEAR(CREATED)
 
+### FROM_UNIXTIME
+
+```FROM_UNIXTIME (unixtime, formatString,timeZone)```
+
+Convert the number of seconds from the UNIX epoch (1970-01-01 00:00:00 UTC) to a string representing the timestamp of that moment.
+
+The most important format characters are: y year, M month, d day, H hour, m minute, s second. For details of the format, see `java.time.format.DateTimeFormatter`.
+
+`timeZone` is optional, default value is system's time zone.  `timezone` value can be a `UTC+ timezone offset`, for example, `UTC+8` represents the Asia/Shanghai time zone, see `java.time.ZoneId`
+
+This method returns a string.
+
+Example:
+
+// use default zone
+
+CALL FROM_UNIXTIME(1672502400, 'yyyy-MM-dd HH:mm:ss')
+
+or
+
+// use given zone
+
+CALL FROM_UNIXTIME(1672502400, 'yyyy-MM-dd HH:mm:ss','UTC+6')
+
 ## System Functions
 
 ### CAST

release-note.md

@@ -19,7 +19,7 @@
 ### Formats
 - [Canal]Support read canal format message #3950
 - [Debezium]Support debezium canal format message #3981
- 
+
 ### Connector-V2
 
 - [Json-format] [Canal-Json] Fix json deserialize NPE (#4195)
@@ -76,6 +76,7 @@
 - [Zeta] Fix cpu load problem (#4828)
 - [zeta] Fix the deadlock issue with JDBC driver loading (#4878)
 - [zeta] dynamically replace the value of the variable at runtime (#4950)
+- [Zeta] Add from_unixtime function (#5462)
 - [zeta] Fix CDC task restore throw NPE (#5507)
 
 ### E2E

seatunnel-e2e/seatunnel-transforms-v2-e2e/seatunnel-transforms-v2-e2e-part-2/src/test/java/org/apache/seatunnel/e2e/transform/TestSQLIT.java

@@ -46,6 +46,9 @@ public void testSQLTransform(TestContainer container) throws IOException, Interr
         Container.ExecResult sqlFuncSystem =
                 container.executeJob("/sql_transform/func_system.conf");
         Assertions.assertEquals(0, sqlFuncSystem.getExitCode());
+        Container.ExecResult sqlFuncFromUnixtime =
+                container.executeJob("/sql_transform/func_from_unixtime.conf");
+        Assertions.assertEquals(0, sqlFuncFromUnixtime.getExitCode());
         Container.ExecResult sqlCriteriaFilter =
                 container.executeJob("/sql_transform/criteria_filter.conf");
         Assertions.assertEquals(0, sqlCriteriaFilter.getExitCode());

seatunnel-e2e/seatunnel-transforms-v2-e2e/seatunnel-transforms-v2-e2e-part-2/src/test/resources/sql_transform/func_from_unixtime.conf

@@ -0,0 +1,67 @@
+#
+# 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.
+#
+######
+###### This config file is a demonstration of streaming processing in seatunnel config
+######
+
+env {
+  execution.parallelism = 1
+  job.mode = "BATCH"
+  checkpoint.interval = 10000
+}
+
+source {
+  FakeSource {
+    result_table_name = "fake"
+    schema = {
+      fields {
+        unixtime = "bigint"
+      }
+    }
+    rows = [
+      {fields = [1672502400], kind = INSERT}
+    ]
+  }
+}
+
+transform {
+  Sql {
+    source_table_name = "fake"
+    result_table_name = "fake1"
+    query = "select from_unixtime(unixtime,'yyyy-MM-dd HH:mm:ss','UTC+8') as ts from fake"
+  }
+}
+
+sink {
+  Console {
+    source_table_name = "fake1"
+  }
+  Assert {
+    source_table_name = "fake1"
+    rules = {
+      field_rules = [
+        {
+          field_name = "ts"
+          field_type = "string"
+          field_value = [
+            {equals_to = "2023-01-01 00:00:00"}
+          ]
+        }
+      ]
+    }
+  }
+}

seatunnel-transforms-v2/src/main/java/org/apache/seatunnel/transform/sql/zeta/ZetaSQLFunction.java

@@ -155,6 +155,7 @@ public class ZetaSQLFunction {
     public static final String SECOND = "SECOND";
     public static final String WEEK = "WEEK";
     public static final String YEAR = "YEAR";
+    public static final String FROM_UNIXTIME = "FROM_UNIXTIME";
 
     // -------------------------system functions----------------------------
     public static final String COALESCE = "COALESCE";
@@ -377,6 +378,8 @@ public Object executeFunctionExpr(String functionName, List<Object> args) {
                 return DateTimeFunction.dayOfWeek(args);
             case DAY_OF_YEAR:
                 return DateTimeFunction.dayOfYear(args);
+            case FROM_UNIXTIME:
+                return DateTimeFunction.fromUnixTime(args);
             case EXTRACT:
                 return DateTimeFunction.extract(args);
             case FORMATDATETIME:

seatunnel-transforms-v2/src/main/java/org/apache/seatunnel/transform/sql/zeta/ZetaSQLType.java

@@ -217,6 +217,7 @@ private SeaTunnelDataType<?> getFunctionType(Function function) {
             case ZetaSQLFunction.DAYNAME:
             case ZetaSQLFunction.MONTHNAME:
             case ZetaSQLFunction.FORMATDATETIME:
+            case ZetaSQLFunction.FROM_UNIXTIME:
                 return BasicType.STRING_TYPE;
             case ZetaSQLFunction.ASCII:
             case ZetaSQLFunction.LOCATE:

seatunnel-transforms-v2/src/main/java/org/apache/seatunnel/transform/sql/zeta/functions/DateTimeFunction.java

@@ -23,10 +23,12 @@
 
 import java.text.DateFormatSymbols;
 import java.time.Duration;
+import java.time.Instant;
 import java.time.LocalDate;
 import java.time.LocalDateTime;
 import java.time.LocalTime;
 import java.time.Period;
+import java.time.ZoneId;
 import java.time.format.DateTimeFormatter;
 import java.time.temporal.Temporal;
 import java.time.temporal.TemporalAccessor;
@@ -541,4 +543,20 @@ public static Integer year(List<Object> args) {
         LocalDate localDate = convertToLocalDate(datetime);
         return localDate.getYear();
     }
+
+    public static String fromUnixTime(List<Object> args) {
+        Long unixTime = (Long) args.get(0);
+        if (unixTime == null) {
+            return null;
+        }
+        String format = (String) args.get(1);
+        ZoneId zoneId = ZoneId.systemDefault();
+        if (args.size() == 3) {
+            String timeZone = (String) args.get(2);
+            zoneId = ZoneId.of(timeZone);
+        }
+        DateTimeFormatter df = DateTimeFormatter.ofPattern(format);
+        LocalDateTime datetime = Instant.ofEpochSecond(unixTime).atZone(zoneId).toLocalDateTime();
+        return df.format(datetime);
+    }
 }

seatunnel-transforms-v2/src/test/java/org/apache/seatunnel/transform/sql/zeta/DateTimeFunctionTest.java

@@ -0,0 +1,65 @@
+/*
+ * 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.seatunnel.transform.sql.zeta;
+
+import org.apache.seatunnel.api.table.type.BasicType;
+import org.apache.seatunnel.api.table.type.SeaTunnelDataType;
+import org.apache.seatunnel.api.table.type.SeaTunnelRow;
+import org.apache.seatunnel.api.table.type.SeaTunnelRowType;
+import org.apache.seatunnel.transform.sql.SQLEngine;
+import org.apache.seatunnel.transform.sql.SQLEngineFactory;
+
+import org.junit.jupiter.api.Assertions;
+import org.junit.jupiter.api.Test;
+
+public class DateTimeFunctionTest {
+
+    @Test
+    public void testFromUnixtimeFunction() {
+
+        SQLEngine sqlEngine = SQLEngineFactory.getSQLEngine(SQLEngineFactory.EngineType.ZETA);
+
+        SeaTunnelRowType rowType =
+                new SeaTunnelRowType(
+                        new String[] {"unixtime"}, new SeaTunnelDataType[] {BasicType.LONG_TYPE});
+
+        // 1672502400 means `2023-01-01 12:00:00 UTC+8` in unix time
+        Long unixTime = 1672545600L;
+        SeaTunnelRow inputRow = new SeaTunnelRow(new Long[] {unixTime});
+
+        // transform by `from_unixtime` function
+        sqlEngine.init(
+                "test",
+                null,
+                rowType,
+                "select from_unixtime(unixtime,'yyyy-MM-dd') as ts from test");
+        SeaTunnelRow outRow = sqlEngine.transformBySQL(inputRow);
+        Object field = outRow.getField(0);
+        Assertions.assertNotNull(field.toString());
+
+        // transform by `from_unixtime` time zone function
+        sqlEngine.init(
+                "test",
+                null,
+                rowType,
+                "select from_unixtime(unixtime,'yyyy-MM-dd HH:mm:ss','UTC+6') as ts from test");
+        SeaTunnelRow outRow1 = sqlEngine.transformBySQL(inputRow);
+        Object field1 = outRow1.getField(0);
+        Assertions.assertEquals("2023-01-01 10:00:00", field1.toString());
+    }
+}