Flume 1.6.0 spooling directory source with timestamp on header - hadoop

Question

I'm trying to create a new flume agent like source spooldir and puts them in HDFS. This is my config file:
agent.sources = file
agent.channels = channel
agent.sinks = hdfsSink
# SOURCES CONFIGURATION
agent.sources.file.type = spooldir
agent.sources.file.channels = channel
agent.sources.file.spoolDir = /path/to/json_files
# SINKS CONFIGURATION
agent.sinks.hdfsSink.type = hdfs
agent.sinks.hdfsSink.hdfs.path = /HADOOP/PATH/%Y/%m/%d/%H/
agent.sinks.hdfsSink.hdfs.filePrefix = common
agent.sinks.hdfsSink.hdfs.fileSuffix = .json
agent.sinks.hdfsSink.hdfs.rollInterval = 300
agent.sinks.hdfsSink.hdfs.rollSize = 5242880
agent.sinks.hdfsSink.hdfs.rollCount = 0
agent.sinks.hdfsSink.hdfs.maxOpenFiles = 2
agent.sinks.hdfsSink.hdfs.fileType = DataStream
agent.sinks.hdfsSink.hdfs.callTimeout = 100000
agent.sinks.hdfsSink.hdfs.batchSize = 1000
agent.sinks.hdfsSink.channel = channel
# CHANNELS CONFIGURATION
agent.channels.channel.type = memory
agent.channels.channel.capacity = 10000
agent.channels.channel.transactionCapacity = 1000
I'm getting an error that describes Expected timestamp in the Flume event headers, but it was null. The files that I'm reading contains JSON structure, which has a field named timestamp.
Is there a way to add this timestamp in the header?

Answer 1

As per my earlier comment, now I am sharing the entire steps which I followed and performed for spooling header enable json file, putting it to hadoop hdfs cluster using flume, creating a external file over json file and later performed DML query over it -
Created flume-spool.conf
//Flume Configuration Starts
erum.sources =source-1
erum.channels =file-channel-1
erum.sinks =hdfs-sink-1
erum.sources.source-1.channels =file-channel-1
erum.sinks.hdfs-sink-1.channel =file-channel-1
//Define a file channel called fileChannel on erum
erum.channels.file-channel-1.type =file
erum.channels.file-channel-1.capacity =2000000
erum.channels.file-channel-1.transactionCapacity =100000
//Define a source for erum
erum.sources.source-1.type =spooldir
erum.sources.source-1.bind =localhost
erum.sources.source-1.port =44444
erum.sources.source-1.inputCharset =UTF-8
erum.sources.source-1.bufferMaxLineLength =100
//Spooldir in my case is /home/arif/practice/flume_sink
erum.sources.source-1.spoolDir =/home/arif/practice/flume_sink/
erum.sources.source-1.fileHeader =true
erum.sources.source-1.fileHeaderKey=file
erum.sources.source-1.fileSuffix =.COMPLETED
//Sink is flume_import under hdfs
erum.sinks.hdfs-sink-1.pathManager =DEFAULT
erum.sinks.hdfs-sink-1.type =hdfs
erum.sinks.hdfs-sink-1.hdfs.filePrefix =common
erum.sinks.hdfs-sink-1.hdfs.fileSuffix =.json
erum.sinks.hdfs-sink-1.hdfs.writeFormat =Text
erum.sinks.hdfs-sink-1.hdfs.fileType =DataStream
erum.sinks.hdfs-sink-1.hdfs.path =hdfs://localhost:9000/user/arif/flume_sink/products/
erum.sinks.hdfs-sink-1.hdfs.batchSize =1000
erum.sinks.hdfs-sink-1.hdfs.rollSize =2684354560
erum.sinks.hdfs-sink-1.hdfs.rollInterval =5
erum.sinks.hdfs-sink-1.hdfs.rollCount =5000
Now we are running the flume-spool using agent - erum
bin/flume-ng agent -n erum -c conf -f conf/flume-spool.conf -Dflume.root.logger=DEBUG,console
Copied the products.json file inside the erum.sources.source-1.spoolDir flume configured specified directory.
Contents inside the products.json file is as follows as it were -
{"productid":"5968dd23fc13ae04d9000001","product_name":"sildenafilcitrate","mfgdate":"20160719031109","supplier":"WisozkInc","quantity":261,"unit_cost":"$10.47"}
{"productid":"5968dd23fc13ae04d9000002","product_name":"MountainJuniperusashei","mfgdate":"20161003021009","supplier":"Keebler-Hilpert","quantity":292,"unit_cost":"$8.74"}
{"productid":"5968dd23fc13ae04d9000003","product_name":"DextromathorphanHBr","mfgdate":"20161101041113","supplier":"Schmitt-Weissnat","quantity":211,"unit_cost":"$20.53"}
{"productid":"5968dd23fc13ae04d9000004","product_name":"MeophanHBr","mfgdate":"20161101061113","supplier":"Schmitt-Weissnat","quantity":198,"unit_cost":"$18.73"}
Download the hive-serdes-sources-1.0.6.jar from below url-
https://www.dropbox.com/s/lsjgk2zaqz8uli9/hive-serdes-sources-1.0.6.jar?dl=0
After spooling the json file to hdfs cluster using flume-spool, we will start the hive server, login to hive shell and then do the following-
hive> add jar /home/arif/applications/hadoop/apache-hive-2.1.1-bin/lib/hive-serdes-sources-1.0.6.jar;
hive> create external table products (productid string, product_name string, mfgdate string, supplier string, quantity int, unit_cost string)
> row format serde 'com.cloudera.hive.serde.JSONSerDe' location '/user/arif/flume_sink/products/';
OK
Time taken: 0.211 seconds
hive> select * from products;
OK
5968dd23fc13ae04d9000001 sildenafilcitrate 20160719031109 WisozkInc 261 $10.47
5968dd23fc13ae04d9000002 MountainJuniperusashei 20161003021009 Keebler-Hilpert 292 $8.74
5968dd23fc13ae04d9000003 DextromathorphanHBr 20161101041113 Schmitt-Weissnat 211 $20.53
5968dd23fc13ae04d9000004 MeophanHBr 20161101061113 Schmitt-Weissnat 198 $18.73
Time taken: 0.291 seconds, Fetched: 4 row(s)
and I have completed these entire steps without any single error, hope this will help you, thanks.

Answer 2

as explained in this post:
http://shzhangji.com/blog/2017/08/05/how-to-extract-event-time-in-apache-flume/
the changes needed is to include an interceptor and serializer to it:
# SOURCES CONFIGURATION
agent.sources.file.type = spooldir
agent.sources.file.channels = channel
agent.sources.file.spoolDir = /path/to/json_files
agent.sources.file.interceptors = i1
agent.sources.file.interceptors.i1.type = regex_extractor
agent.sources.file.interceptors.i1.regex = <regex_for_timestamp>
agent.sources.file.interceptors.i1.serializers = s1
agent.sources.file.interceptors.i1.serializers.s1.type = org.apache.flume.interceptor.RegexExtractorInterceptorMillisSerializer
agent.sources.file.interceptors.i1.serializers.s1.name = timestamp
agent.sources.file.interceptors.i1.serializers.s1.pattern = <pattern_that_matches_your_regex>
thanks for pointing out that besides the link i needed to include a proper snippet :)