Good morning, Steve. Indeed, that second paragraph is *exactly* how I did
get this to work. I unpack to disk and then read in the twelve results
using a GetFile. So far it is working well. It just feels a little wrong to
me to do this, as I have introduced an extra write to and read from disk,
which is going to be slower than doing it all in memory within the JVM.
While that may not seem like anything significant for a single 7z file, as
we work across thousands and thousands it can be significant.
I am about to try what you suggested above: dropping the ${filename}
entirely from the STDIN / STDOUT configuration. I realize it is not likely
going to give me the twelve output flowfiles I'm seeking in the "output
stream" path from ExecuteStreamCommand. I just want to see if it works
without throwing that error.
Welcome any other thoughts or comments you may have. Thanks again for your
comments so far.
Jim
On Thu, Sep 29, 2022 at 5:23 AM <stephen.hindma...@bt.com> wrote:
> James,
>
>
>
> I have been thinking more about your problem and this may be the wrong
> approach. If you successfully unpack your files into the flow file content,
> you will still have one output flow file containing the unpacked contents
> of all of your files. If you need 12 separate files in their own flowfiles
> then you will need to find some way of splitting them up. Is there a byte
> sequence you can use in a SplitContent process, or a specific file length
> you can use in SplitText?
>
>
>
> Otherwise you may be better off using ExecuteStreamCommand to unpack the
> files on disk. Run it verbosely and use the output of that step to create a
> list of the locations where your recently unpacked files are. Or create a
> temporary directory to unpack in and fetch all the files in there, cleaning
> up aftwerwards. Then you can load the files with FetchFile. FetchFile can
> be instructed to delete the file it has just read so can also clean up
> after itself.
>
>
>
> *Steve Hindmarch*
>
>
>
> *From:* stephen.hindmarch.bt.com via users <users@nifi.apache.org>
> *Sent:* 29 September 2022 09:19
> *To:* jsmcmah...@gmail.com; users@nifi.apache.org
> *Subject:* RE: Can ExecuteStreamCommand do this?
>
>
>
> James,
>
>
>
> Using ${filename} and -si together seems wrong to me. What happens when
> you try that on the command line?
>
>
>
> *Steve Hindmarch*
>
>
>
> *From:* James McMahon <jsmcmah...@gmail.com>
> *Sent:* 28 September 2022 13:49
> *To:* users@nifi.apache.org; Hindmarch,SJ,Stephen,VIR R <
> stephen.hindma...@bt.com>
> *Subject:* Re: Can ExecuteStreamCommand do this?
>
>
>
> Thank you Steve. I 've employed a ListFile/FetchFile to load the 7z files
> into the flow . When I have my ESC configured like this following, I get my
> unpacked files results to the #{unpacked.destination} directory on disk:
>
> Command Arguments
> x;${filename};-spf;-o#{unpacked.destination};-aou
>
> Command Path /bin/7a
>
> Ignore STDIN true
>
> Working Directory #{unpacked.destination}
>
> Argument Delimiter ;
>
> Output Destination Attribute No value set
>
> I get twelve files in my output destination folder.
>
>
>
> When I try this one, get an error and no output:
>
> Command Arguments x;${filename};-si;-so;-spf;-aou
>
> Command Path /bin/7a
>
> Ignore STDIN false
>
> Working Directory #{unpacked.destination}
>
> Argument Delimiter ;
>
> Output Destination Attribute No value set
>
>
>
> This yields this error...
>
> Executable command /bin/7za ended in an error: ERROR: Can not open the
> file as archive
>
> E_NOTIMPL
>
> ...and it yields only one flowfile result in Output Stream, and that is a
> brief text/plain report of the results of the 7za extraction like this:
>
>
>
> This indicates it did indeed find my 7z file and it did indeed identify
> the 12 files in it, yet still I get no output to my outgoing flow path:
>
> Extracting archive: /parent/subparent/testArchive.7z
>
> - -
>
> Path = /parentdir/subdir/testArchive.7z
>
> Type = 7z
>
> Physical Size = 7204
>
> Headers Size = 298
>
> Method = LZMA2:96k
>
> Solid = +
>
> Blocks = 1
>
>
>
> Everything is Ok
>
>
>
> Folders: 1
>
> Files: 12
>
> Size: 90238
>
> Compressed: 7204
>
>
>
> ${filename} in both cases is a fully qualified name to the file, like
> this: /dir/subdir/myTestFile.7z.
>
>
>
> I can't seem to get the ESC output stream to be the extracted files.
> Anything jump out at you?
>
>
>
> On Wed, Sep 28, 2022 at 8:06 AM stephen.hindmarch.bt.com
> <https://eur02.safelinks.protection.outlook.com/?url=http%3A%2F%2Fstephen.hindmarch.bt.com%2F&data=05%7C01%7Cstephen.hindmarch%40bt.com%7C54f1ea8bb7ef4ddff5d008daa1f37d7c%7Ca7f356889c004d5eba4129f146377ab0%7C0%7C0%7C638000364398005114%7CUnknown%7CTWFpbGZsb3d8eyJWIjoiMC4wLjAwMDAiLCJQIjoiV2luMzIiLCJBTiI6Ik1haWwiLCJXVCI6Mn0%3D%7C3000%7C%7C%7C&sdata=PKfbxWRL8NpVcjn96XkRclrXszldqA94HF1WphfQ%2BBA%3D&reserved=0>
> via users <users@nifi.apache.org> wrote:
>
> Hi James,
>
>
>
> I am not in a position to test this right now, but you have to think of
> the flowfile content as STDIN and STDOUT. So with 7zip you need to use the
> “-si” and “-so” flags to ensure there are no files involved. Then if you
> can load the content of a file into a flowfile, eg with GetFile, then you
> should be able to unpack it with ExecuteStreamCommand. Set “Ignore STDIN” =
> “false”.
>
>
>
> I have written up my own use case on github. This involves having a Redis
> script as the input, and results of the script as the output.
>
>
>
> my-nifi-cluster/experiment-redis_direct.md at main ·
> hindmasj/my-nifi-cluster · GitHub
> <https://eur02.safelinks.protection.outlook.com/?url=https%3A%2F%2Fgithub.com%2Fhindmasj%2Fmy-nifi-cluster%2Fblob%2Fmain%2Fdocs%2Fexperiment-redis_direct.md&data=05%7C01%7Cstephen.hindmarch%40bt.com%7C54f1ea8bb7ef4ddff5d008daa1f37d7c%7Ca7f356889c004d5eba4129f146377ab0%7C0%7C0%7C638000364398005114%7CUnknown%7CTWFpbGZsb3d8eyJWIjoiMC4wLjAwMDAiLCJQIjoiV2luMzIiLCJBTiI6Ik1haWwiLCJXVCI6Mn0%3D%7C3000%7C%7C%7C&sdata=vHRMqJBJsrW3p7MzSXaGcGZHGmTiIzGmdgqqsTjh30E%3D&reserved=0>
>
>
>
> The first part of the post shows how to do it with the input commands on
> the command line, so a bit like you running “7za ${filename} -so”. The
> second part has the script inside the flowfile and is treated as STDIN, a
> bit like you doing “unzip -si -so”.
>
>
>
> See if that helps. Fundamentally, if you do “7za -si -so < myfile.7z” on
> the command line and see the output on the console, ExecuteStreamCommand
> will behave the same.
>
>
>
> *Steve Hindmarch*
>
> *From:* James McMahon <jsmcmah...@gmail.com>
> *Sent:* 28 September 2022 12:02
> *To:* users@nifi.apache.org
> *Subject:* Can ExecuteStreamCommand do this?
>
>
>
> I continue to struggle with ExecuteStreamCommand, and am hoping one of you
> from our user community can help me with the following:
>
> 1. Can ExecuteStreamCommand be used as I am trying to use it?
>
> 2. Can you direct me to an example where ExecuteStreamCommand is
> configured to do something similar to my use case?
>
>
>
> My use case:
>
> The incoming flowfiles in my flow path are 7z zips. Based on what I've
> researched so far, NiFi's native processors don't handle unpacking of 7z
> files.
>
>
>
> I want to read the 7z files as STDIN to ExecuteStreamCommand.
>
> I'd like the processor to call out to a 7za app, which will unpack the 7z.
>
> One incoming flowfile will yield multiple output files. Let's say twelve
> in this case.
>
> My goal is to output those twelve as new flowfiles out of
> ExecuteStreamCommand, to its output stream path.
>
>
>
> I can't yet get this to work. Best I've been able to do is configure
> ExecuteStreamCommand to unpack ${filename} to a temporary output directory
> on disk. Then I have another path in my flow polling that directory every
> few minutes looking for new data. Am hoping to eliminate that intermediate
> write/read to/from disk by keeping this all within the flow and JVM memory.
>
>
>
> Thanks very much in advance for any assistance.
>
>
