更改火花中的时间戳TZ

时间:2019-05-29 09:43:12

标签: python apache-spark timezone user-defined-functions

我有一个包含时间戳记(unix)的日期框架:

df = spark.createDataFrame(
    [
        (1527853209,),
        (1527852466,),
        (1527852178,),
        (1527851689,),
        (1527852214,),
    ],
    ["date_time"]
)

,我使用下面的spark配置:

OPT_SPARK = {
    'master': 'yarn',
    'spark.executor.extraJavaOptions': '-Duser.timezone=GMT',
    'spark.driver.extraJavaOptions': '-Duser.timezone=GMT',
}
  

在不更改启动选项的情况下,我想将时间戳从“ GMT”转换为“ CET-中欧时间”。

我尝试了以下代码:

from pyspark.sql import functions as F, types as T
from datetime import datetime 
from dateutil import tz 

def conv(in_ts): 

    from_zone = tz.gettz('GMT') 
    to_zone = tz.gettz('CET') 

    utc = datetime.utcfromtimestamp(in_ts) 
    utc = utc.replace(tzinfo=from_zone)
    n_ts = utc.astimezone(to_zone).replace(tzinfo=None)

    return n_ts


conv_udf = F.udf(conv, T.TimestampType()) 

当我测试该功能时,它工作正常,但不是在火花中:

# 1527853209 is GMT: Friday 1 June 2018 11:40:09
conv(1527853209)
datetime.datetime(2018, 6, 1, 13, 40, 9)

df.select( 
    "date_time",
    F.col("date_time").cast("timestamp"), 
    conv_udf("date_time")
).show() 

+----------+-------------------+-------------------+
| date_time|          date_time|    conv(date_time)|
+----------+-------------------+-------------------+
|1527853209|2018-06-01 11:40:09|2018-06-01 11:40:09|
|1527852466|2018-06-01 11:27:46|2018-06-01 11:27:46|
|1527852178|2018-06-01 11:22:58|2018-06-01 11:22:58|
|1527851689|2018-06-01 11:14:49|2018-06-01 11:14:49|
|1527852214|2018-06-01 11:23:34|2018-06-01 11:23:34|
+----------+-------------------+-------------------+

我找不到任何内置函数来实现此目的,因此使用UDF似乎是最好的解决方案,但显然,它无法按预期工作。

预期结果

+----------+-------------------+-------------------+
| date_time|          date_time|    conv(date_time)|
+----------+-------------------+-------------------+
|1527853209|2018-06-01 11:40:09|2018-06-01 13:40:09|
|1527852466|2018-06-01 11:27:46|2018-06-01 13:27:46|
|1527852178|2018-06-01 11:22:58|2018-06-01 13:22:58|
|1527851689|2018-06-01 11:14:49|2018-06-01 13:14:49|
|1527852214|2018-06-01 11:23:34|2018-06-01 13:23:34|
+----------+-------------------+-------------------+

1 个答案:

答案 0 :(得分:0)

我认为您的操作是正确的,但是当您使用show()打印结果时,您的conv(date_time)就会被转移到您的时区(GMT)。

如果您唯一需要的是在新时区(CET)中显示日期时间,则可以将udf重写为StringType:

def conv(in_ts):

from_zone = tz.gettz('GMT')
to_zone = tz.gettz('CET')

utc = datetime.utcfromtimestamp(in_ts)
utc = utc.replace(tzinfo=from_zone)
n_ts = utc.astimezone(to_zone)

return n_ts.strftime('%x %X')


conv_udf = F.udf(conv, T.StringType())