Jim, If you only need to read the contents of the flow file and not modify them, then you don't have to use session.write() to send the original content out, you can just use session.read(FlowFile, InputStreamCallback) instead.
I'm not sure why that write fails sometimes and not others, I suspect it is something either in the particular input or perhaps a bug in Jython. Regards, Matt On Tue, Jan 23, 2018 at 11:23 AM, James McMahon <[email protected]> wrote: > Good afternoon. I have a python script that attempts to execute a stream > callback. I use re to extract content out of the incoming stream represented > as a string. After extracting the content I need, I save these as attributes > and attempt to write back my original content to the output stream. It works > almost all the time, but occasionally the ExecuteScript processor hangs with > the error message: > TypeErro: write(): 1st arg can't be coerced to byte[], int in script at line > number 184 > > I use an ExecuteScript with python as the ScriptEngine. > Line 184 in my script folds the call to the callback into a session.write, > like so: > flowFile = session.write(flowFile, PyStreamCallback()) > > In my callback method I catch the contents of my stream in a string, like > so: > trailer = IOUtils.toString(inputStream,StandardCharsets.UTF_8) > I use re expressions to pattern match for nuggets I later save as > attributes. > > I use this to output back to my stream: > outputStream.write(bytearray(trailer.encode('utf-8'))) > This almost always works, but fails on rare occasions because, well, I don't > think I'm smart enough to know how to bullet-proof the output stream write. > > Can anyone show me how to modify this outputStream.write to overcome this > impediment? Bottom line: I simply want to send the inputStream back to the > outputStream at this point (I have saved all i parsed out to a python > dictionary accessible to me later in my script). If there's a better form of > the outputStream write I am using that directly references the input stream, > that may eliminate my impediment. > > I am running on an older version of Apache NiFi, 0.7.x. > > Thanks very much for any assistance, > Jim
