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How to convert unix timestamp to datetime in Apache NiFi?

How to convert unix timestamp to datetime in Apache NiFi?

New Contributor

Hi everyone!
In my FlowFile, using components, I listen to logs from Squid in the form of txt. Then I add columns and separate the log elements. The output file is csv, because in the future it will be added to the Hive database.
The problem occurs when I want to change the type of the "datetime" variable from unix timestamp to the usual date time.

Based on this solution: https://community.hortonworks.com/articles/131320/using-partitionrecord-grokreaderjsonwriter-to-pars...

This is how the log sent by Squid looks like using a proxy:

1518442283.483 161 127.0.0.1 TCP_MISS/200 103701 GET http://www.cnn.com/ matt DIRECT/199.27.79.73 text/html

This is Grok Expression (in GrokReader):
%{NUMBER:timestamp}\s+%{NUMBER:duration}\s%{IP:client_address}\s%{WORD:cache_result}/%{POSINT:status_code}\s%{NUMBER:bytes}\s%{WORD:request_method}\s%{NOTSPACE:url}\s(%{NOTSPACE:user}|-)\s%{WORD:hierarchy_code}/%{IPORHOST:server}\s%{NOTSPACE:content_type}

The following links include:
→ General appearance of components: https://imgur.com/a/fn2Q03N
→ Settings for the UpdateRecord component: https://imgur.com/a/E8gfMj8
→ Settings for the UpdateRecord/GrokReader(nifi_mid): https://imgur.com/a/l8He75D
→ Settings for the UpdateRecord/CSVRecordSetWriter: https://imgur.com/a/aqiZ98M

My problem is described on stackoverflow: https://stackoverflow.com/questions/48885675/conversion-unix-timestamp-attribute-to-normal-date

13 REPLIES 13

Re: How to convert unix timestamp to datetime in Apache NiFi?

Super Collaborator

did you just left out the timestamp from the log entry, or is a log line exactly as you provided? In your example you only have 1 number preceding the IP address, but you try to read two numbers (timestamp and duration)?

Re: How to convert unix timestamp to datetime in Apache NiFi?

New Contributor

I'm sorry, I did not paste the value for unix timestamp by mistake. My value for timestamp is 1518442283.483, and the next is:
duration: 161,
client_address: 127.0.0.1,
cache_result: TCP_MISS,
status_code: 200,
bytes: 103701,
request_method: GET,
url: http://www.cnn.com/,
user: matt,
hierarchy_code: DIRECT,
server: 199.27.79.73,
content_type: text/html.

Re: How to convert unix timestamp to datetime in Apache NiFi?

Rising Star

Hi @Wojtek,

I believe the problem is that the format() function works only with numbers. Your timestamp has a '.' (dot) which makes it interpret as a string.

To solve the problem I have adopted the following EL un a updateAttribute processor:

${ts:substringBefore('.'):append(${ts:substringAfter('.')})
	:toNumber():format('MM/dd/yyyy HH:mm:ss.SSS')
}

ts attribute contains this value 1518442283.483

the result is 02/12/2018 13:31:23.483

I hope I have been of help

Re: How to convert unix timestamp to datetime in Apache NiFi?

New Contributor

Hello @Davide Isoardi,

thank you for your answer!
Is this how it should look like adding this method to the UpdateAttribute component?

71389-updateattribute.png
Unfortunately, but nothing has changed.

Re: How to convert unix timestamp to datetime in Apache NiFi?

Rising Star

you must change the attribute on which to perform the transformation. I never used the GrokReader, but I believe you have to change ts to in timestamp in the EL string

Re: How to convert unix timestamp to datetime in Apache NiFi?

New Contributor

I noticed, however, that the problem lies elsewhere. For example, I wanted to check if I change the value of the user attribute using the toUpper () function. Unfortunately, but at the exit the user's name was still written in lowercase.

71390-updateattribute.png

Result is:
datetime,duration,client_address,cache_result,status_code,bytes,request_method,url,user,hierarchy_code,server,content_type 1518442283.483,161,127.0.0.1,TCP_MISS,200,103701,GET,http://www.cnn.com/,matt,DIRECT,199.27.79.73,text/html

Re: How to convert unix timestamp to datetime in Apache NiFi?

Master Guru
@Davide Isoardi

-

The UpdateAttribute processor does not read the content of a FlowFile. In order for the above Expression Language statements to work, the incoming FlowFile's must have FlowFile attributes "user" and "datetime" created on them.
-
Stop the UpdateAttribute processor and allow a few FlowFiles to queue. Then list that queue and verify what attributes currently exist on those listed FlowFiles.

-

Thanks,

Matt

Re: How to convert unix timestamp to datetime in Apache NiFi?

New Contributor

@Matt Clarke, thank you for your answer!
I turned off the UpdateAttribute component and turned on the entire flow again. Below are screenshots:

71430-off-updateattribute.png

71431-listqueue.png

71432-dataprovenance.png

71436-attributes.png

When I re-enabled the UpdateAttribute to component, the information about the attributes is such that @Matt Clarke is right ↓

71437-datetimeuser.png

Re: How to convert unix timestamp to datetime in Apache NiFi?

Rising Star

sorry for the mistake, obviously the operation is performed on the attribute, not on the FlowFile. So you must first set the values you need in the attributes and then transform them.

Thanks @Matt Clarke