question Re: NiFi: FetchFile processor appends new line at end in Archives of Support Questions (Read Only)

NiFi: FetchFile processor appends new line at end

ashsskum — Sun, 18 Dec 2016 17:36:50 GMT

When you retrieve the content of a file through above processor, in the flowfile we can see a new line character appended at the end. Is this an expected behavior? Any reason for this behavior and how it can be avoided?

Re: NiFi: FetchFile processor appends new line at end

gkeys — Mon, 19 Dec 2016 01:36:59 GMT

FetchFile does not append a new line character if it is not present in the original file.

When I run ListFiles -> FetchFile -> PutFile and view in text editor, the file content is identical among the following files (including new line characters viewable via the text editor):

original file on disk
file contents downloaded from FetchFile (Provenance/Contents)
file contents downloaded from PutFile (Provenance/Contents)
file put to disk

If you are not getting this behavior, please provide details.

Re: NiFi: FetchFile processor appends new line at end

ashsskum — Sun, 18 Aug 2019 12:01:25 GMT

Sample file:

NiFi flow:

After Fetchfile (flowfile content):

Re: NiFi: FetchFile processor appends new line at end

dpinkston — Sun, 18 Aug 2019 12:01:06 GMT

@Kumar

The NiFi provenance UI adds a newline to your content. If you go look at the raw file being fetched or moved through the FetchFile processor you will notice that there actually isn't a new line appended. If I use the same input you do, my provenance UI will show a new line (line 2) after the text "Line1", identical to your screenshot.

However if i look at where the "move" content of the fetchFile Processor is placed, i see that there isn't a newline. Also if i do a putFile i notice there isn't a newline either. Below are some screenshots to show:

Raw file:

Provenance shows a new line (line 2):

The output of Putfile:

The output of having MoveFile in the fetchFile processor:

The overall flow used to test:

Re: NiFi: FetchFile processor appends new line at end

gkeys — Mon, 19 Dec 2016 20:12:25 GMT

@Kumar, as tests by me and @Devin Pinkston show, it is the actual file content that you need to look at (not the UI). Thus ... no fears of the processor adding a new line.