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Flume, mail # user - Why does a Flume source need to recognize the format of the message?


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Re: Why does a Flume source need to recognize the format of the message?
Roshan Naik 2013-10-22, 21:21
i forgot to note that syslog source also does some parsing.
On Tue, Oct 22, 2013 at 1:51 PM, Roshan Naik <[EMAIL PROTECTED]> wrote:

> At a minimum it needs to know how to split incoming data into individual
> events. Typically a newline is used as the separator.
>
>  Avro & thrift are special purpose sources/sinks which handle headers and
> body. Avro, Thrift & HTTP sources will parse the incoming data into header
> + body. AFAIKT most other sources treat the whole thing as a body. They
> should not need any more info other than line/event delimiter.
>
> You can write custom deserializer which is supported by some sources to
> parse custom incoming data format.
>
> -roshan
>
>
>
> On Tue, Oct 22, 2013 at 11:07 AM, Jarek Jarcec Cecho <[EMAIL PROTECTED]>wrote:
>
>> Hi Praveen,
>> I think that there is a confusion between message and payload. Whereas
>> Flume do not need to understand the payload structure, it do need to
>> understand the message to understand what events (what payloads) are there
>> with what headers. To put it differently, Flume do not need to understand
>> structure of the data that you are sending (payload is just a byte array
>> for Flume), but that unknown structure needs to be transferred via known
>> protocol (such as AVRO RPC).
>>
>> Jarcec
>>
>> On Tue, Oct 22, 2013 at 06:59:17PM +0100, Praveen Sripati wrote:
>> > According to the Flume documentation
>> >
>> > >>    A Flume source consumes events delivered to it by an external
>> source
>> > like a web server. The external source sends events to Flume in a format
>> > that is recognized by the target Flume source. For example, an Avro
>> Flume
>> > source can be used to receive Avro events from Avro clients or other
>> Flume
>> > agents in the flow that send events from an Avro sink.
>> >
>> > Why does a Flume source need to recognize or understand the format of
>> the
>> > message? While all it does it does is to forward the message to one of
>> the
>> > channel.
>> >
>> > Thanks,
>> > Praveen
>>
>
>

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