You are viewing an old version of this page. View the current version.

Compare with Current View Page History

« Previous Version 73 Next »

The PyWPS software was originally developed to use under Linux (Debian). However, it is also possible to use the software in a Windows environment for example for testing purposes. To do so, Apache server has to be installed on the system. For Linux installation see this manual.

Step 0

Make sure Python is pre-installed on your machine, we recommend PythonXY (version 2.7, not 3.x).

After install, start a NEW command line prompt and go to the root and check if :

  • Python version is 2.7,Result should be like:

    Show Python version
    C:\>python --version
    Python 2.7.6
  • Python package magic is installed and of version 0.4.6 else see  Known Installation Issues

    Python-Magic package versionnr
    C:\>pip show python-magic
    ---
    Name: python-magic
    Version: 0.4.6
    PyPi Version: 0.4.6
    Location: c:\python27\lib\site-packages
    home_page: http://github.com/ahupp/python-magic
    Summary: File type identification using libmagic
    Requires:
    Required by(0):
  • Python package lxml is installed and of version 3.3.5 else download http://www.microsoft.com/en-us/download/details.aspx?id=44266, install this c++ compiler and install lxml with this command : 
    pip install lxml 
    Python lxml package
    C:\>pip show lxml
    ---
    Name: lxml
    Version: 3.3.5
    PyPi Version: 3.4.0
    Location: c:\python27\lib\site-packages
    home_page: http://lxml.de/
    Summary: Powerful and Pythonic XML processing library combining libxml2/libxslt
    with the ElementTree API.
    Requires:
    Extra Require [source]: cython(-)
    Extra Require [cssselect]: cssselect
    Extra Require [html5]: html5lib
    Extra Require [htmlsoup]: beautifulsoup4
    Required by(5): html5lib[optional], pandas[html], astropy[optional], astropy[doc
    ], beautifulsoup4[optional]

Step 1

Download PyWPS (version 3.2.1, not 3.2.2)

Step 2

Unpack the contents of PyWPS folder and save the entire folder as c:\pywps. Such that you have c:\pywps\wps.py. Check if it works command line in python by navigating to c:\pywps and execute this command:

Test if pywps works on your system
C:\>cd pywps

C:\pywps>wps.py
PyWPS NoApplicableCode: Locator: None; Value: No query string found. Content-Type: application/xml

<?xml version="1.0" encoding="utf-8"?>
<ExceptionReport version="1.0.0" xmlns="http://www.opengis.net/ows/1.1" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://www.opengis.net ows/1.1 http://schemas.opengis.net/ows/1.1.0/owsExceptionReport.xsd">
        <Exception exceptionCode="NoApplicableCode">
                <ExceptionText>'No query string found.'</ExceptionText>
        </Exception>
</ExceptionReport>

Step 3

  1. Create a folder called c:\pywps\pywps_processes
  2. Add the file default.cfg (from c:\pywps\pywps) into it. If you like you can insert your own information in the file. 
    However, do not forget to :
    1. Set the correct path for tempPath(c:/pywps/temp) under [server] section.
    2. Set outputPath (c:/[webserver]/htdocs/wps/wpsoutput) under [server] section.
    3. Set processesPath to c:/pywps/pywps_processes
    4. Set the logFile to somewhere (c:/pywps/log)

The path slashes should conform to python conventions, which happen to be the same as the linux slash convention, and not the windows convention. Note that python paths should never end with a slash!.

Step 4

Navigate to the Apache folder.

If the Apache web server is not installed in your machine yet, download the newest stable release of Apache (https://httpd.apache.org/download.cgi).

After installation, in the Apache folder c:\Program Files (x86)\Apache Software Foundation\Apache2.2 you find a sub folder called cgi-bin.

Create an empty file called pywps.cgi in this folder and insert the following code in it, after checking the python path (and correcting it: for example if you have Python2.7 installed, the first line should be #!c:\python27\python.exe):

pywps.cgi
#!C:\python27\python.exe
import sys
sys.path.insert(0, r"C:/pywps")
import os
os.environ['PYWPS_CFG']='C:/pywps/pywps_processes/default.cfg'
os.environ['MPLCONFIGDIR']='C:/Python27/Lib/site-packages/matplotlib/mpl-data'
# Note that WPS runs as apache user and not as you, so many more user variables might be needed.
# Restart Apache after adding one.
import wps

Step 5

Install the PyWPS Python package:

  • On the command line in the pywps folder c:\pywps> type python c:\pywps\setup.py install
  • Or open the Windows command line tool (start > run), drag and drop setup.py from your c:\pywps folder, type install after the location of the setup file and click ok. The PyWPS Python package will now be installed.)

Check if it is installed correctly into python like this :

Show installed python PyWPS version
C:\>pip show pywps
---
Name: pywps
Version: 3.2.1
PyPi Version: trunk
Location: c:\python27\lib\site-packages\pywps-3.2.1-py2.7.egg
home_page: http://pywps.wald.intevation.org
Summary: PyWPS: Implementation of OGC's Web Processing Service in Python
Requires:
Required by(0):

 

Step 6

Test your WPS by starting Apache server and navigate to http://localhost/cgi-bin/pywps.cgi  The result should be something similar to this, meaning that the pywps process runs correctly inside the apache web server.

<ExceptionReport xmlns="http://www.opengis.net/ows/1.1" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" version="1.0.0" xsi:schemaLocation="http://www.opengis.net/ows/1.1 http://schemas.opengis.net/ows/1.1.0/owsExceptionReport.xsd">
	<Exception exceptionCode="NoApplicableCode">
		<ExceptionText>'No query string found.'</ExceptionText>
	</Exception>
</ExceptionReport>

Step 7

Now pywps runs, test for correct WPS behaviour in browser using the syntax in WPS Primer. In c:\pywps\tests\processes some example processes are included, copy its entire contents to the c:\pywps\pywps_processes folder (that you configured as processesPath=c:/pywps/pywps_processes in c:\pywps\pywps_processes\default.cfg) and find out whether you can get them to run. First test the GetCapabilities request:

<wps:Capabilities service="WPS" version="1.0.0" xml:lang="en-CA" xsi:schemaLocation="http:/opengis.net/wps/1.0.0 http://schemas.opengis.net/wps/1.0.0/wpsGetCapabilities_response.xsd" updateSequence="1">
...
</wps:Capabilities>

and then executing any of the available processes
e.g. http://localhost/cgi-bin/pywps.cgi?service=wps&request=Execute&Identifier=dummyprocess&DataInputs=\[input1=42\]&version=1.0.0.

Step 8

Now add your own Python processes as WPS by copying your processes to the c:\pywps\pywps_processes folder too. Use the WPS syntax (Setting up a WPS process using PyWPS) for your python functions as in the copied examples. Change 3 things when adding a new WPS process based on these examples:

  1. add new file XYZ.py to c:/pywps/pywps_processes
  2. change identifier inside XYZ.py
  3. add "XYZ.py" to c:/pywps/pywps_processes/_init_.py

Known installation issues

  • If the GetCapabilities request gives you this error

    in your html browser, please check your apache error.log in c:\Program Files (x86)\Apache Software Foundation\Apache2.2\logs.

    • In some cases it might contain this error message ImportError: No module named magic\r. In this case please manually install the python-magic package from https://github.com/ahupp/python-magic. For your convenience we included a windows distributable win32 Python2.7 version until the official binary is available at github. Restart apache afterwards (type services in your windows start menu or click small apache icon in icon tray). If you still get errors (failed to find libmagic in the aforementioned Apache error.log) install cygwin http://cygwin.com/install.html which contains the magic dll. Set the path where the cygmagic-1.dll resides c:\Program Files (x86)\Cygwin\bin in the windows $PATH environment variable so magic.py can find it (bear in mind that this should be the System Variables Path setting).

      • If you don't want to have cygwin on your machine just copy the following dynamic link library (dll) files from the cygwin installation to the python root directory (where python.exe resides) and uninstall / remove cygwin:
        1. cygmagic-1.dll
        2. cyggcc_s-1.dll
        3. cygwin1.dll
        4. cygz.dll
      • Pay attention to the CPU Type installation, if you have installed a 64 bits python use 64 bits libs!!
    • In some cases it might contain this error message : ImportError: No module named Template\r\r ; You probably have installed PyWPS version 3.2.2. Please remove this version and download and install version 3.2.1.

  • The following error AttributeError: 'exceptions.ImportError' object has no attribute 'replace'\r is caused by the fact that step 7 is not fully followed. So put some processes in your processes folder and try the GetCapabilities again.
  • If you run this in a Virtual windows machine (e.g. via VMWare), regular disk mappings might not work in WPS because WPS runs as another users (apache), please try references like //vmware-host/Shared%20Folders/D/ instead of simply D.
  • Errors like these for import statements in a WPS process, e.g. import matplotlib causes

    PyWPS [2014-03-19 14:58:23,112] WARNING: Could not import processes from 'pywps_processes': ImportError('No module named pwd',) 

    have to do with the fact that WPS runs under apache user, so add any required user environmental
    variables to c:\Program Files (x86)\Apache Software Foundation\Apache2.2\cgi-bin\pywps.cgi:

    pywps.cgi
    os.environ['MPLCONFIGDIR']='C:/Python27/Lib/site-packages/matplotlib/mpl-data'
    
  • If the GetCapabilities request gives you this error

 

Notes:

 

  • Official documentation on PyWPS (v3.2.0) can be found here
  • To install basemap you can follow the instructions here

Acknowlegdements The first version of this documentation was made by MSc student Joost Boerboom for his thesis, financed by Deltares under the Next Generation Hydro Software program executed for Rijkswaterstaat. Subsequently, this documentation was improved by Deltares in projects EMODnet chemistry and ECOSTRESS.

  • No labels