10.2 GP service creates file - how to write it so I can actually retrieve it

FrankMcLean

Hi,

I am tearing out my hair (which I can ill afford to do) over being able to retrieve a file I create via a GP service.  Very simplified:-

1. Let's say I have a Python script which takes no input parameters.
2. It creates a file called 'HelloWorld.txt', which is empty.

That's it.  This runs fine on the desktop and I can retrieve HelloWorld.txt.  Yippee.

When I publish this, successfully, and run it, successfully, I cannot for the life of me get the file.  I've tried a lot of stuff:

1. Writing to 'nowhere', i.e. just HelloWorld.txt = written in job scratch area, result url goes to a scratch folder which gives an HTTP 400, Invalid URL.
2. Writing to 'scratch' via arcpy.env.scratchFolder = same as above
3. Writing to the 'current workspace' via arcpy.env.workspace = empty on server, same as above
4. Etc

What it _appears_ I need to do is to somehow write to the 'Output Directory' specified for the service, which has a nice accompanying 'Virtual Directory'.  Am I right?  How on earth do I get this location?  Would doing that even cause the url to be mapped to that location?  Why is this so hard?  🙂  You just publish a GP result, right?  Hooray!

Sorry.  You can probably tell this has my mind in knots.

Please, if someone could provide the Python snippet that will do this, I would be most grateful.  I might even make a T Shirt out of it, grow a beard and travel the world evangelizing about it, because this should be EASY, front and center whenever someone outputs a file as a script result and wants to publish it.  I'm asking for a Python snippet, rather than a URL to help docs, because "I've been everywhere, man!" and really doubt those will shed any light.  DO NOT let this put you off attempting to help, however. 🙂  I'll be truly grateful for any crumbs.

I just wanted it to work like the print task works.  You get a nice URL that you download from and go on with your life.  This seemed like it must be a five minute job.  Tops.

Thanks for listening!

Frank

KevinHibma

I think you're falling into the mindset a lot of people do when trying to return a file.
My first bit of advice is to not over think it (yeah, easier said then done, I know).

If you have a tool in Desktop that works...ie, a python script tool that outputs a file, you have a parameter that either is output required or a derived output - either way, its of type FILE.
You run this tool in Desktop, open the results window, expand that successful result and there will be the output file you can double click. If you're output a txt file, double clicking it should open it in notepad (or whatever you PC opens .txt files with).

Now moving to Server, dont over think it assuming you need to return a URL or worry about virtual directories. The GP/Server framework handles all of this. The only thing that changes in terms of GP Server and file output is the client consuming the service. If your client happens to be ArcMap, run the tool from your server connection. Expand the result in the Results window and double click the result. Exact same experience...ArcMap as a client handled getting the file down from the Server and helped you open it.
If your client is the Services Directory (REST Endpoint), a successful result will return a link you can click to download the file.
If your client is a web app, you do need to write some code to handle getting the result and saving it (well telling the browser to popup a box and save it).

Apologies if I'm off base and you understand this bit - if your question is "how do I write the python code to output a file", well it should be handled as well. In short, your code could be this simple (assuming input parameter of string and derived output parameter of file)

import arcpy import os  getInputTxt = arcpy.GetParameterAsText(0)  txtFile = os.path.join(arcpy.env.scratchFolder, "myTxt.txt") f = open(txtFile, 'w') f.writelines(getInputTxt) f.close  arcpy.SetParameterAsText(1, txtFile)