Gunjan,

There are many ways of skinning this cat indeed... :-)

Another reasonably efficient strategy for those looking to perform high
speed enrichment against structured single match data sources may use
QueryDNS processor in regex or split parsing together with a synthetic DNS
server acting as bridge to a database or data source.

It works pretty much like and dynamic anti-SPAM black list:

1. Spin up PowerDNS using the pipe packend (that published the data you
want to enrich against) consulting the enrichment data source;
2. Point NiFi QueryDNS to resolve using the PowerDNS instance as name
server (TXT records work very well with data up to 253 characters)
3. Use the attributes added by QueryDNS to do take decisions within NiFi.

The setup above scales out very well for small length enrichment and you
can use multiple QueryDNS processors and powerDNS sub-domains to perform
multiple stages of enrichment.

Also worth of notice is the fact the use of DNS (UDP) allows the DFM to
design enrichment paths that "fail open" (via DNS query timeout) in case of
outage affecting the data source.

Cheers


On Sat, Sep 3, 2016 at 12:07 PM, Gunjan Dave <gunjanpiyushd...@gmail.com>
wrote:

> How i have handled this personally is to use wrap sql processors with
> handlehttprequest processor essentially making the db operation as a REsT
> webservice.
>
> Then you have the option of fetchhttp processor update appending the
> results in attribute instead of content, which is an option already
> available.
>
> With mongo db, you need not do this additional operation of wrapping as it
> has a REST interface so directly use that in http processor.
>
> On Sat, Sep 3, 2016, 4:28 AM Matt Burgess <mattyb...@apache.org> wrote:
>
>> Agreed.  Additionally, if we want to get fancy, we can work with
>> incoming flow files based on MIME type (JSON, XML, CSV) and have a
>> "Path" property to a field in the document. Then the processor could
>> replace inline the value in the document with the lookup value. If XML
>> files are coming in, the Path is an XPath expression. Same for JSON
>> and JSONPath, and CSV could be a column index (0-based, e.g.).
>>
>> I have something very similar (not the lookup, but the "Path" thing
>> for multiple file types) coming soon as a Jira case / PR ;) If that
>> proves useful, I could move it into a util or base class or something.
>>
>> Regards,
>> Matt
>>
>> On Fri, Sep 2, 2016 at 6:47 PM, Manish Gupta 8 <mgupt...@sapient.com>
>> wrote:
>> > I think the lookup processor should return data in a format that can be
>> > efficiently parsed/processed by NiFi expression language. For example –
>> > JSON. This would avoid using additional “Extract” type processor. All
>> the
>> > downstream processor can simply work with “jsonPath” for additional
>> lookup
>> > inside the attribute.
>> >
>> >
>> >
>> > Regards,
>> >
>> > Manish
>> >
>> >
>> >
>> > From: Matt Burgess [mailto:mattyb...@gmail.com]
>> > Sent: Friday, September 02, 2016 6:37 PM
>> >
>> >
>> > To: users@nifi.apache.org
>> > Subject: Re: Processor to enrich attribute from external service
>> >
>> >
>> >
>> > Manish,
>> >
>> >
>> >
>> > Some of the queries in those processors could bring back lots of data,
>> and
>> > putting them into an attribute could cause memory issues. Another
>> concern is
>> > when the result is binary data, such as ExecuteSQL returning an Avro
>> file.
>> > And since the return of these is a collection of records, these
>> processors
>> > are often followed by a Split processor to perform operations on
>> individual
>> > records.
>> >
>> >
>> >
>> > Having said that, if the return value is text and you'd like to
>> transfer it
>> > to an attribute, you can use ExtractText to put the content into an
>> > attribute. For small content (which is the appropriate use case), this
>> > should be pretty fast, and keeps the logic in a single processor
>> instead of
>> > duplicated (either logically or physically) across processors.
>> >
>> >
>> >
>> > By the way I'm very interested in an RDBMS lookup processor, but not
>> sure
>> > I'd have time in the short run to write it up. If someone takes a crack
>> at
>> > it, I recommend properties to pre-cache the table with a refresh
>> interval.
>> > This way if the lookup table doesn't change much and is not too big, it
>> > could be read into the processor's memory for super-fast lookups.
>> > Alternatively, a property could be a cache size, which would build a
>> subset
>> > of the table in memory as values are looked up. This is probably more
>> robust
>> > as it is bounded and if the size is set high enough for a small table,
>> it
>> > would be read in its entirety. Still would want the cache refresh
>> property
>> > though.
>> >
>> >
>> >
>> > Cheers,
>> >
>> > Matt
>> >
>> >
>> > On Sep 2, 2016, at 6:19 PM, Manish Gupta 8 <mgupt...@sapient.com>
>> wrote:
>> >
>> > Thanks for the reply Joe. Just a thought – do you think it would be a
>> good
>> > idea for every Get processor (GetMongo, GetHBase etc.) to have 2
>> additional
>> > properties like:
>> >
>> > 1.      Result in Content or Result in Attribute
>> >
>> > 2.      Result Attribute Name (only applicable when “Result in
>> Attribute” is
>> > selected).
>> >
>> > But then all such processors should be able to accept incoming flowfile
>> > (which they don’t as of now – being a “Get”).
>> >
>> >
>> >
>> > May be ExecuteSQL and FetchDistributeMapCache can be enhanced that way
>> i.e.
>> > have an option to specify the destination – content or attribute?
>> >
>> >
>> >
>> > Regards,
>> >
>> > Manish
>> >
>> >
>> >
>> > From: Joe Witt [mailto:joe.w...@gmail.com]
>> > Sent: Friday, September 02, 2016 5:58 PM
>> > To: users@nifi.apache.org
>> > Subject: Re: Processor to enrich attribute from external service
>> >
>> >
>> >
>> > You would need to make a custom process for now.  I think we should
>> have a
>> > nice controller service to generalize jdbc lookups which supports
>> caching.
>> > And then a processor which leverages it.
>> >
>> > This comes up fairly often and is pretty straightforward from a design
>> POV.
>> > Anyone want to take a stab at this?
>> >
>> >
>> >
>> > On Sep 2, 2016 4:47 PM, "Manish Gupta 8" <mgupt...@sapient.com> wrote:
>> >
>> > Hello Everyone,
>> >
>> >
>> >
>> > Is there a processor that we can use for updating/adding an attribute
>> of an
>> > incoming flow file from some external service (say MongoDB or Couchbase
>> or
>> > any RDBMS)? The processor will use the attribute of incoming flow file,
>> > query the external service, and simply modify/add an additional
>> attribute of
>> > flow-file (without touching the flow file content).
>> >
>> >
>> >
>> > If we have to achieve this kind of “lookup” operation (but only to
>> update
>> > attribute and not the content), what are the options in NiFi?
>> >
>> > Should we create a custom processor (may be by taking GetMongo
>> processor and
>> > modifying its code to update an attribute with query result)?
>> >
>> >
>> >
>> > Thanks,
>> >
>> > Manish
>> >
>> >
>>
>

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