Python: Batch resize and pad files

When using AI models like Stable Diffusion, sometimes input images need to be of a specific size. In case of Stable Diffusion, multiples of 64 are required. Stable Diffusion (at least 1.5) works best with images of 512 pixels in width or height. If you for example take an image of 599 x 205 pixels and you resize it to 1496 x 512 (maintaining the aspect ratio), you end up with 1496, which is not a multiple of 64. In order to obtain a usable image, it needs to be padded to a size of 1536 x 512 to allow processing. In order to batch resize and pad images I created a Python script using OpenCV. Why create a script? Doing this for a large amount of images quickly becomes a chore and writing a script for this is fun. Why OpenCV? It is powerful, easy to use and popular.

Apache NiFi: Automating tasks using NiPyAPI

Apache NiFi has a powerful web-based interface which provides a seamless experience between design, control, feedback, and monitoring. Sometimes however, you want to automate tasks instead of doing them manually using the UI. This does not only allow you to perform the tasks a lot quicker but it also helps make them more reproducible. It allows you to incorporate tasks in for example a CI/CD system without requiring human intervention. A NiFi feature to help you automate tasks is its powerful API. In order to more easily use this API from Python, NiPyAPI is available. In this blog post I'll describe some things you can do with NiPyAPI, some challenges I encountered and how I fixed them. You can find my sample code here.

Python: A Google Translate service using Playwright

There are a lot of use-cases in which you might want to automate a web-browser. For example to automate tedious repetitive tasks or to perform automated tests of front-end applications. There are also several tools available to do this such as Selenium, Cypress and Puppeteer. Several blog posts and presentations by Lucas Jellema picked my interest in Playwright so I decided to give it a try. I'm not a great fan of JavaScript so I decided to go with Python for this one. I also did some tests with wrk, a simple yet powerful HTTP bench-marking tool, to get an indication about how Playwright would handle concurrency and was not disappointed.

HTTP benchmarking using wrk. Parsing output to CSV or JSON using Python

wrk is a modern HTTP benchmarking tool. Using a simple CLI interface you can put simple load on HTTP services and determine latency, response times and the number of successfully processed requests. It has a LuaJIT scripting interface which provides extensibility. A distinguishing feature of wrk compared to for example ab (Apache Bench) is that it requires far less CPU at higher concurrency (it uses threads very efficiently). It does have less CLI features when compared to ab. You need to do scripting to achieve specific functionality. Also you need to compile wrk for yourself since no binaries are provided, which might be a barrier to people who are not used to compiling code.

Parsing the wrk output is a challenge. It would be nice to have a feature to output the results in the same units as CSV or JSON file. More people asked this question and the answer was: do some LuaJIT scripting to achieve that. Since I'm no Lua expert and to be honest, I don't have any people in my vicinity that are, I decided to parse the output using Python (my favorite language for data processing and visualization) and provide you with the code so you don't have to repeat this exercise.

You can see example Python code of this here.   

Graceful shutdown of forked workers in Python and JavaScript running in Docker containers

You might encounter a situation where you want to fork a script during execution. For example if the amount of forks is dependent on user input or another specific situation. I encountered such a situation in which I wanted to put load on a service using multiple concurrent processes. In addition, when running in a docker container, only the process with PID=1 receives a SIGTERM signal. If it has terminated, the worker processes receive a SIGKILL signal and are not allowed a graceful shutdown. In order to do a graceful shutdown of the worker processes, the main process needs to manage them and only exit after the worker processes have terminated gracefully. Why do you want processes to be terminated gracefully? In my case because I store performance data in memory (disk is too slow) and only write the data to disk when the test has completed.

This seems relatively straightforward, but there are some challenges. Also I implemented this in JavaScript running on Node and in Python. Python and JavaScript handle forking differently.

Using Python to performancetest an Oracle DB

Performance testing is a topic with many opinions and complexities. You can not do it in a way which will make everyone happy. It is not straightforward to compare measures before and after a change. Environments are often not stable (without change in itself and its environment). When performing a test, the situation at the start or end of the test are also often not the same. For example the test might write data in a database.

There are various ways to look at performance. You can look at user experience, generate load similar to what application usage produces or you can do more basic things like query performance. What will you be looking at? Resource consumption and throughput are the usual suspects.

I'll look at a simple example in this blog post. I'll change database parameters and look at throughput of various actions which are regularly performed on databases. This takes away the complexity of distributed systems. I used a single Python script for this which can be downloaded here.

Summary of conclusions: Exposing database functionality using a DAD is not so much influenced by the tested settings. Setting FILESYSTEMIO_OPTIONS to SETALL improved the performance of almost all database actions. This has also been observed at different customers. Disabling Transparent HugePages and enabling the database to use HugePages seemed to have little effect. PL/SQL native compilation also did not cause a massive improvement. From the tested settings FILESYSTEMIO_OPTIONS is the easiest to apply. Query performance and actions involving a lot of data improved with all (and any of) these settings.

Automate calls to SOAP and REST webservices using simple Python scripts

Probably not many people will tell you running batches over webservices is a good idea. Sometimes though, it can be handy to have a script available to generate webservice calls based on a template message with variables and automate processing the response messages. In addition, if you have a large number of calls, executing the calls in parallel might save you a lot of time if your service platform can handle the concurrency.

WebLogic Server: Automate obtaining performance metrics from DMS

Oracle provides the Dynamic Monitoring Service (DMS) as part of WebLogic Server which is extremely useful if you want to obtain aggregated data of an environment in case of for example a performance test. The data which can be obtained from DMS is extensive. This varies from average duration of service calls to JVM garbage collects to datasource statistics. DMS can be queried with WLST.  See for example here. On example script based on this can be found here. You can also directly go to a web-interface such as: http://<host>:<port>/dms/Spy. The DMS Spy servlet is by default only enabled on development environments but can be deployed on production environments (see here).

Obtaining data from DMS in an automated fashion, even with the WLST support, can be a challenge. In this blog I provide a Python 2.7 script which allows you to get information from the DMS and dump it in a CSV file for further processing. The script first logs and uses the obtained session information to download information from a specific table in XML. This XML is converted to CSV. The code does not require an Oracle Home (it is not WLST based). The purpose here is to provide an easy to use starting point which can be expanded to suit specific use-cases. The script works against WebLogic 11g and 12c environments (has been tested against 11.1.1.7 and 12.2.1). Do mind that the example URL given in the script obtains performance data on webservice operations. This works great on composites but not on Service Bus or JAX-WS services. You can download a general script here (which requires minimal changes to use) and a (more specific) script with examples of how to preprocess data in the script here.

Sonatype Nexus 2.x: Using the REST API to clean-up your repository

Sonatype provides Nexus. An extensive artifact Repository Manager. It can hold large amounts of stored artifacts and still requests get processed quickly. Also it has an extensive easy to use API which is a definite asset. When a project has been running for a longer period (say years), the repository often gets filled with large numbers of artifacts. This can become especially troublesome if artifacts are quite large in size such as for example JSF EAR files. These artifacts might not even have been released (be part of a deployed release). Nexus provides the option to remove artifacts older than a specific date. This however might also remove artifacts which are dependencies of other artifacts (older releases) which you might want to keep. When those other artifacts are build, the build might break because the artifacts it refers to, have been removed. In order to allow more fine grained control over what to remove, I've created the following script. The script uses only the releases repository (snapshots are not taken into account. not sure what the script does there) Disclaimer: first test if this script does what you want in your situation. It is provided as is without any warranties.

Simple IoT security system using Raspberry Pi 2B + Razberry + Fibaro Motion Sensor (FGMS-001)

In this article I'll describe how I created a simple home-brew burglar detection system to send me a mail when someone enters my house (so I can call the police). First my choice for the components is explained. Next how these components combine to achieve the functionality wanted. Based on this article you should be able to avoid certain issues I encountered and have a nice suggestion for a simple relatively cheap burglar detection system.

My purpose was to create a simple security system based on a Raspberry Pi. A Raspberry Pi is a tiny computer which can run a Debian like Linux distribution called Rasbian. I wanted to avoid going to low-level into sensor configuration and programming. That's why I decided early on to use an extension board and not directly attach the sensors to the Raspberry Pi. I decided to go for the Razberry. I also looked at the GrovePi and Arduino. Both are still too low-level for my tastes though. The Razberry is an extension board for the Raspberry which provides a Z-Wave controller chip. Z-Wave is a wireless protocol popular in the area of home automation. This was an attractive option since if in the future I would want to use additional sensors or maybe even use a commercial home automation system, I could very well get compatibility out of the box. For the sensor, I decided on the Fibaro FGMS-001 Motion Sensor. This is a multi-sensor which allows detection of motion, temperature, luminiscence and vibrations. It can even detect tampering and earthquakes (which is relevant since I live in the Dutch city of Groningen).

Z-Wave.Me (the company providing the Razberry), provides software for the Razberry called Z-Way. There are several alternatives. One of the most popular seems to be Domoticz which is provided with OpenZWave. Domoticz allows quite extensive home automation but I was having difficulty getting the sensor to work with OpenZWave so I decided to go with Z-Way. Z-Way supported the sensor out of the box. With the Z-Way server however it was difficult to automate actions based on sensor values. How I solved this is also described in this article.

How to use WLST as a Jython 2.7 module

WebLogic Scripting Tool (WLST) in WebLogic Server 12.1.3 uses Jython version 2.2.1 (based on Python 2.2.1). This can be an important limitation when using WLST. Many modules are not available for 2.2.1 or are difficult to install. See here for an example. WLST however can be used as a module in Jython 2.7. This allows you to use all kinds of nice Jython 2.7 goodness while still having all the great WLST functionality available.

To just name some nice Jython 2.7 features:

• pip and easy_install can be used to easily add new modules
• useful new API’s are available such as xml.etree.ElementTree to allow XML processing, the multiprocessing module to use multiple threads and the argparse module to make parsing of script arguments easy.

In this article I’ll describe how you can use WLST as a Jython 2.7 module in order to allow you to combine the best of both worlds in your scripts.

Create a release of artifacts. Automate adding Maven dependencies

"Continuous Delivery (CD) is a software engineering approach in which teams keep producing valuable software in short cycles and ensure that the software can be reliably released at any time." (from here)

Software artefacts are developed using a build pipeline. This pipeline consists of several steps to provide quick feedback on software quality by means of code quality checks, automated tests, test coverage checks, etc. When the software is done (adhering to a Definition of Done (DoD)), it is released. This release as a whole is then tested and promoted until it reaches a production environment. In the meantime, work on a next release has already started. This process is shown in the below image. This is a minimal example (especially on the test part). In the below image, you can see there are 3 releases in progress. This is only in order to illustrate the process. You should of course try to limit the number of releases which are not in production to reduce the overhead of fixes on those releases.

Cleaning up unused namespaces in Oracle SOA 11g BPEL processes by using a Python script

Composites are often created and after creating, they are changed/expanded to implement functionality or bugfixes. When adding new partnerlinks and variables, removing them, importing new XSD, removing them, etc it often occurs that there are namespace definitions inside for example BPEL processes which are no longer relevant because they are not used anymore. This can adversely effect performance/memory usage and increases the chance of errors when XSD's are changed, removed or added (such as inconsistent duplicate namespace definitions).

I took this issue as a nice opportunity to learn myself a bit of Python. Python is a popular scripting language (http://www.tiobe.com/index.php/content/paperinfo/tpci/index.html) and used by several software vendors such as Oracle for Weblogic server; WLST (http://docs.oracle.com/cd/E14571_01/web.1111/e13813/quick_ref.htm) and ESRI (http://esripress.esri.com/display/index.cfm?fuseaction=display&websiteID=224&moduleID=0) for GIS related programming. There is an official Python tutorial available on http://docs.python.org/3.3/tutorial/ and I've also used http://www.vogella.com/articles/Python/article.html to learn some basics.

First impression of the Python language
- I like the usage of indentation compared to the use of brackets or end statements
- code completion is far from perfect with the PyDev plug-in for Eclipse when using Python 3.3 (I needed to Google a lot for API documentation)
- even without background in Python, you can quickly get something working after reading some tutorials (although I have some experiences with other scripting languages like PERL, PHP, JavaScript. I usually use PERL for my regular scripting needs).

Implementation

Purpose

I wanted to create a script which would cleanup unused namespaces in XML files. I started with a BPEL file as an example (the same example as used in; http://javaoraclesoa.blogspot.nl/2013/04/soa-suite-ps6-11117-service-loose.html. It can be downloaded here; https://dl.dropboxusercontent.com/u/6693935/blog/HelloWorldTokens.zip). The BPEL file had the following contents;

<?xml version = "1.0" encoding = "UTF-8" ?>
<!--
////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
  Oracle JDeveloper BPEL Designer
 
  Created: Thu Apr 11 12:23:10 CEST 2013
  Author:  Maarten
  Type: BPEL 2.0 Process
  Purpose: Synchronous BPEL Process
////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
-->
<process name="CallHelloWorld"
               targetNamespace="http://xmlns.oracle.com/HelloWorld/CallHelloWorld/CallHelloWorld"
               xmlns="http://docs.oasis-open.org/wsbpel/2.0/process/executable"
               xmlns:client="http://xmlns.oracle.com/HelloWorld/CallHelloWorld/CallHelloWorld"
               xmlns:ora="http://schemas.oracle.com/xpath/extension"
               xmlns:bpelx="http://schemas.oracle.com/bpel/extension"
         xmlns:bpel="http://docs.oasis-open.org/wsbpel/2.0/process/executable"
         xmlns:ns1="http://xmlns.oracle.com/HelloWorld/HelloWorld/HelloWorld">

    <import namespace="http://xmlns.oracle.com/HelloWorld/CallHelloWorld/CallHelloWorld" location="CallHelloWorld.wsdl" importType="http://schemas.xmlsoap.org/wsdl/"/>
    <!--
      ////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
        PARTNERLINKS                                                     
        List of services participating in this BPEL process              
      ////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
    -->
  <partnerLinks>
    <!--
      The 'client' role represents the requester of this service. It is
      used for callback. The location and correlation information associated
      with the client role are automatically set using WS-Addressing.
    -->
    <partnerLink name="callhelloworld_client" partnerLinkType="client:CallHelloWorld" myRole="CallHelloWorldProvider"/>
    <partnerLink name="HelloWorld" partnerLinkType="ns1:HelloWorld"
                 partnerRole="HelloWorldProvider"/>
  </partnerLinks>

  <!--
    ////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
      VARIABLES                                                       
      List of messages and XML documents used within this BPEL process
    ////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
  -->
  <variables>
    <!-- Reference to the message passed as input during initiation -->
    <variable name="inputVariable" messageType="client:CallHelloWorldRequestMessage"/>

    <!-- Reference to the message that will be returned to the requester-->
    <variable name="outputVariable" messageType="client:CallHelloWorldResponseMessage"/>
    <variable name="InvokeHelloWorld_process_InputVariable"
              messageType="ns1:HelloWorldRequestMessage"/>
    <variable name="InvokeHelloWorld_process_OutputVariable"
              messageType="ns1:HelloWorldResponseMessage"/>
  </variables>

  <!--
    ////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
     ORCHESTRATION LOGIC                                              
     Set of activities coordinating the flow of messages across the   
     services integrated within this business process                 
    ////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
  -->
  <sequence name="main">

    <!-- Receive input from requestor. (Note: This maps to operation defined in CallHelloWorld.wsdl) -->
    <receive name="receiveInput" partnerLink="callhelloworld_client" portType="client:CallHelloWorld" operation="process" variable="inputVariable" createInstance="yes"/>
    <assign name="Assign1">
      <copy>
        <from>$inputVariable.payload/client:input</from>
        <to>$InvokeHelloWorld_process_InputVariable.payload/ns1:input</to>
      </copy>
    </assign>
    <invoke name="InvokeHelloWorld"
            partnerLink="HelloWorld" portType="ns1:HelloWorld"
            operation="process"
            inputVariable="InvokeHelloWorld_process_InputVariable"
            outputVariable="InvokeHelloWorld_process_OutputVariable"
            bpelx:invokeAsDetail="no"/>
    <assign name="Assign2">
      <copy>
        <from>$InvokeHelloWorld_process_OutputVariable.payload/ns1:result</from>
        <to>$outputVariable.payload/client:result</to>
      </copy>
    </assign>
    <!-- Generate reply to synchronous request -->
    <reply name="replyOutput" partnerLink="callhelloworld_client" portType="client:CallHelloWorld" operation="process" variable="outputVariable"/>
  </sequence>
</process>

The ora namespace was not used in this process but it is specified in the process tag.

lxml

Based on the following I started with lxml; http://lxml.de/api/lxml.etree-module.html#cleanup_namespaces since it had a function to easily clean unused namespaces and on StackOverflow.com there were many posts on lxml. To install lxml for Windows, I had to first download and install it from http://www.lfd.uci.edu/~gohlke/pythonlibs/#lxml

cleanup_namespaces

My first try was the following;

import lxml.etree as et
filename_in='D:\\dev\\HelloWorld\\CallHelloWorld\\CallHelloWorld.bpel'
filename_out='D:\\dev\\HelloWorld\\CallHelloWorld\\CallHelloWorld.bpel.out'
tree = et.parse(filename_in)
et.cleanup_namespaces(tree)
tree.write(filename_out)

In the output I noticed that although my process definition had been cleaned up from

<process name="CallHelloWorld"
               targetNamespace="http://xmlns.oracle.com/HelloWorld/CallHelloWorld/CallHelloWorld"
               xmlns="http://docs.oasis-open.org/wsbpel/2.0/process/executable"
               xmlns:client="http://xmlns.oracle.com/HelloWorld/CallHelloWorld/CallHelloWorld"
               xmlns:ora="http://schemas.oracle.com/xpath/extension"
               xmlns:bpelx="http://schemas.oracle.com/bpel/extension"
         xmlns:bpel="http://docs.oasis-open.org/wsbpel/2.0/process/executable"
         xmlns:ns1="http://xmlns.oracle.com/HelloWorld/HelloWorld/HelloWorld">

To

<process xmlns="http://docs.oasis-open.org/wsbpel/2.0/process/executable" xmlns:bpelx="http://schemas.oracle.com/bpel/extension" name="CallHelloWorld" targetNamespace="http://xmlns.oracle.com/HelloWorld/CallHelloWorld/CallHelloWorld">

Several namespaces were removed which were in use such as the ns1 namespace which was used in a partnerlink definition as part of an attribute value;

<partnerLink name="HelloWorld" partnerLinkType="ns1:HelloWorld" partnerRole="HelloWorldProvider"/>

My conclusion was that using prebuild functions like the above would most likely not help solve this problem. I did not find a way to limit the functionality to specific namespaces.

Determining used namespaces

I tried a different approach; determine namespaces used in the root element and try to find them on different locations in the BPEL file. Then rewriting the root element.

import lxml.etree as et
import copy
filename_in='D:\\dev\\HelloWorld\\CallHelloWorld\\CallHelloWorld.bpel'
filename_out='D:\\dev\\HelloWorld\\CallHelloWorld\\CallHelloWorld.bpel.out'
tree = et.parse(filename_in)
root=tree.getroot()
nsmap=root.nsmap
nsmapnew= copy.deepcopy(nsmap)

#print (nsmap.values())
namespaces=set(nsmap.values())
print ("Namespaces found: "+str(len(nsmap)))
for nsitem in nsmap:
    found=0
    nscount=0;
    if nsitem != None:
        print ("Processing prefix: "+nsitem+" Namespace: "+nsmap.get(nsitem))
        #processing all elements
        walkAll = tree.getiterator()
        for elt in walkAll:
            #check element
            eltns=elt.xpath('namespace-uri(/*)')
            if eltns==nsmap.get(nsitem):
                found=1
                #print("Found namespace as element namespace")
                break
            if str(elt.text).find(nsitem+":") != -1:
                found=1
                #print("Found prefix as part of element text")
                break
            #check attributes
            for attribute in elt.attrib:
                if attribute.startswith("{"+nsmap.get(nsitem)+"}"):
                    found=1
                    #print ("Found namespace as attribute name namespace")
                    break
                if str(elt.attrib[attribute]).find(nsitem+":") != -1:
                    found=1
                    #print ("Found prefix as part of attribute value")
                    break
    else:
        #default namespace not removing
        found=1
    if found==0:
        print("Not found")
        del nsmapnew[nsitem]
print ("Namespaces remaining: "+str(len(nsmapnew)))

new_root = et.Element(root.tag, attrib=root.attrib,nsmap=nsmapnew)
new_root[:] = root[:]

#to add the top level comment
try:
    firstcomment=root.getprevious()
    new_root.addprevious(firstcomment)
except:
    None

tree = et.ElementTree(new_root)

tree.write(filename_out, xml_declaration=True, encoding='utf-8',pretty_print=True) 

This rewrote my XML like I wanted it to. Even if namespaces were used in XPATH expressions in the BPEL file, they were being recognized as being used. One drawback however was the namespace prefix which was added for all the subelements even though these elements were in the default namespace. I considered using a transformation to fix this. This would however remove the comments from the file so I decided not to. The script output was as followed;

Namespaces found: 6
Processing prefix: ns1 Namespace: http://xmlns.oracle.com/HelloWorld/HelloWorld/HelloWorld
Processing prefix: ora Namespace: http://schemas.oracle.com/xpath/extension
Not found
Processing prefix: client Namespace: http://xmlns.oracle.com/HelloWorld/CallHelloWorld/CallHelloWorld
Processing prefix: bpel Namespace: http://docs.oasis-open.org/wsbpel/2.0/process/executable
Processing prefix: bpelx Namespace: http://schemas.oracle.com/bpel/extension
Namespaces remaining: 5

The created output file was as followed;

<?xml version='1.0' encoding='UTF-8'?>
<!--
////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
  Oracle JDeveloper BPEL Designer
 
  Created: Thu Apr 11 12:23:10 CEST 2013
  Author:  Maarten
  Type: BPEL 2.0 Process
  Purpose: Synchronous BPEL Process
////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
-->
<bpel:process xmlns:ns1="http://xmlns.oracle.com/HelloWorld/HelloWorld/HelloWorld" xmlns:client="http://xmlns.oracle.com/HelloWorld/CallHelloWorld/CallHelloWorld" xmlns:bpel="http://docs.oasis-open.org/wsbpel/2.0/process/executable" xmlns:bpelx="http://schemas.oracle.com/bpel/extension" xmlns="http://docs.oasis-open.org/wsbpel/2.0/process/executable" name="CallHelloWorld" targetNamespace="http://xmlns.oracle.com/HelloWorld/CallHelloWorld/CallHelloWorld"><bpel:import namespace="http://xmlns.oracle.com/HelloWorld/CallHelloWorld/CallHelloWorld" location="CallHelloWorld.wsdl" importType="http://schemas.xmlsoap.org/wsdl/"/>
    <!--
      ////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
        PARTNERLINKS                                                     
        List of services participating in this BPEL process              
      ////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
    -->
  <bpel:partnerLinks>
    <!--
      The 'client' role represents the requester of this service. It is
      used for callback. The location and correlation information associated
      with the client role are automatically set using WS-Addressing.
    -->
    <bpel:partnerLink name="callhelloworld_client" partnerLinkType="client:CallHelloWorld" myRole="CallHelloWorldProvider"/>
    <bpel:partnerLink name="HelloWorld" partnerLinkType="ns1:HelloWorld" partnerRole="HelloWorldProvider"/>
  </bpel:partnerLinks>

  <!--
    ////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
      VARIABLES                                                       
      List of messages and XML documents used within this BPEL process
    ////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
  -->
  <bpel:variables>
    <!-- Reference to the message passed as input during initiation -->
    <bpel:variable name="inputVariable" messageType="client:CallHelloWorldRequestMessage"/>

    <!-- Reference to the message that will be returned to the requester-->
    <bpel:variable name="outputVariable" messageType="client:CallHelloWorldResponseMessage"/>
    <bpel:variable name="InvokeHelloWorld_process_InputVariable" messageType="ns1:HelloWorldRequestMessage"/>
    <bpel:variable name="InvokeHelloWorld_process_OutputVariable" messageType="ns1:HelloWorldResponseMessage"/>
  </bpel:variables>

  <!--
    ////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
     ORCHESTRATION LOGIC                                              
     Set of activities coordinating the flow of messages across the   
     services integrated within this business process                 
    ////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
  -->
  <bpel:sequence name="main">

    <!-- Receive input from requestor. (Note: This maps to operation defined in CallHelloWorld.wsdl) -->
    <bpel:receive name="receiveInput" partnerLink="callhelloworld_client" portType="client:CallHelloWorld" operation="process" variable="inputVariable" createInstance="yes"/>
    <bpel:assign name="Assign1">
      <bpel:copy>
        <bpel:from>$inputVariable.payload/client:input</bpel:from>
        <bpel:to>$InvokeHelloWorld_process_InputVariable.payload/ns1:input</bpel:to>
      </bpel:copy>
    </bpel:assign>
    <bpel:invoke name="InvokeHelloWorld" partnerLink="HelloWorld" portType="ns1:HelloWorld" operation="process" inputVariable="InvokeHelloWorld_process_InputVariable" outputVariable="InvokeHelloWorld_process_OutputVariable" bpelx:invokeAsDetail="no"/>
    <bpel:assign name="Assign2">
      <bpel:copy>
        <bpel:from>$InvokeHelloWorld_process_OutputVariable.payload/ns1:result</bpel:from>
        <bpel:to>$outputVariable.payload/client:result</bpel:to>
      </bpel:copy>
    </bpel:assign>
    <!-- Generate reply to synchronous request -->
    <bpel:reply name="replyOutput" partnerLink="callhelloworld_client" portType="client:CallHelloWorld" operation="process" variable="outputVariable"/>
  </bpel:sequence>
</bpel:process>

The ora namespace had been removed from the process attribute. The file had also become smaller. The ora namespace is however a default Oracle namespace and to make sure I didn't break anything, I tried to compile and deploy the altered process. This was successful. I also tested it with more complex processes. The resulting BPEL file was still fully functional.

Possible followups could be;

- expand the script and allow recursively processing of multiple files and filetypes
- determine used and unused namespaces for every element, not just the root element
- link the results of unused namespaces within a project to XSD's which could also be removed from a project if they are not used by any file in the project
- if for example problems start to occur with XPATH expressions after removing default Oracle namespaces; exclude specific namespaces from cleaning
- remove the namespace prefix for the default namespace