I generate a new dataframe based on the following code:
from pyspark.sql.functions import split, regexp_extract
split_log_df = log_df.select(regexp_extract('value', r'^([^\s]+\s)', 1).alias('host'),
regexp_extract('value', r'^.*\[(\d\d/\w{3}/\d{4}:\d{2}:\d{2}:\d{2} -\d{4})]', 1).alias('timestamp'),
regexp_extract('value', r'^.*"\w+\s+([^\s]+)\s+HTTP.*"', 1).alias('path'),
regexp_extract('value', r'^.*"\s+([^\s]+)', 1).cast('integer').alias('status'),
regexp_extract('value', r'^.*\s+(\d+)$', 1).cast('integer').alias('content_size'))
split_log_df.show(10, truncate=False)
I need another column showing the dayofweek, what would be the best elegant way to create it? ideally just adding a udf like field in the select.
Thank you very much.
Updated: my question is different than the one in the comment, what I need is to make the calculation based on a string in log_df, not based on the timestamp like the comment, so this is not a duplicate question. Thanks.
I suggest a bit different method
from pyspark.sql.functions import date_format
df.select('capturetime', date_format('capturetime', 'u').alias('dow_number'), date_format('capturetime', 'E').alias('dow_string'))
df3.show()
It gives ...
+--------------------+----------+----------+
| capturetime|dow_number|dow_string|
+--------------------+----------+----------+
|2017-06-05 10:05:...| 1| Mon|
|2017-06-05 10:05:...| 1| Mon|
|2017-06-05 10:05:...| 1| Mon|
|2017-06-05 10:05:...| 1| Mon|
|2017-06-05 10:05:...| 1| Mon|
|2017-06-05 10:05:...| 1| Mon|
|2017-06-05 10:05:...| 1| Mon|
|2017-06-05 10:05:...| 1| Mon|