ParaViewWeb on Windows

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This readme described the process of setting up a Paraview Web Server instance on a Windows 10 workstation. Once the ParaView Web is setup, the Visualizer app may be embedded in some other application’s web page (as an internal frame).
Download the correct binariesThis guide has been created while using Paraview 5.2.0 installation binaries. There are a few choices available and among those, the binary for Windows MPI was used. The following details were specified while downloading the file from http://www.paraview.org/download/

Version of ParaView: v5.2 Type of Download: ParaView Binary Installers Operating System: Windows 64 bit File to Download: ParaView-5.2.0-Qt4-OpenGL2-MPI-Windows-64bit.exe

Before installing ParaView, the following libraries need to be present:

• Microsoft Message Passing Interface (MS MPI) Libraries - download the MS MPI libraries from the Microsoft Website
  

Run the downloaded executable file and follow the onscreen installation instructions to install the ParaView Desktop application. Once the application has been installed:

• Start the application, and
• Open a data file and check that the file is properly rendered by the application. Sample data files can be found bundled with the installer.
  

For the purpose of this document, the ParaView application is installed in C: drive in a directory named ParaView-5.2.0 (C:\ParaView-5.2.0). Henceforth, this directory will be referred to as <paraview-root>.
It is recommended that the paraview application is installed in a path which does not  have spaces. For example, installing the application in C:\Program Files\ParaView 5.2.0  is NOT recommended.
Install Apache Web ServerThe Apache web server acts as the front end to the ParaView Web application.
Download Apache Web Server for WindowsThe Apache web server is not natively supported on Windows. To get a Windows installer, a modified server can be downloaded from a number of third party vendors like:

• ApacheHaus
• Apache Lounge
  

Note: It is important to download the corresponding version of Visual C++ Runtime libraries
Once the Apache HTTPD is installed the server needs to be configured for:

• Virtual host
• Integration with ParaView Web
  

Configuring the Apache httpd ServerFor the purpose of this document, the Apache server is extracted to the C: drive in a directory named Apache24 (C:\Apache24). Henceforth, this directory will be referred to as <apache-root>.
Adding Virtual HostsOpen the <apache-root>\conf\extra\httpd-vhosts.conf file and add the following sections:
Grant all access rights in the  directory to the httpd server.

<Directory <paraview-root>>   Require all granted </Directory>

Create a default host config for traffic directed to http://localhost:

<VirtualHost *:80>   DocumentRoot <apache-root>/htdocs   ServerName localhost </VirtualHost>

Create a virutal host named “paraview” which will be used for directing all traffic to the ParaView Web:

<VirtualHost *:80>   ServerName   paraview   ServerAdmin  admin@paraview.com   DocumentRoot <paraview-root>/share/paraview-5.2/web/visualizer/www   ErrorLog <paraview-root>/error.log   CustomLog  <paraview-root>/log/apache2/access.log combined   <Directory "<paraview-root>">       Options Indexes FollowSymLinks       Order allow,deny       Allow from all       AllowOverride None       Require all granted   </Directory>   # Handle launcher forwarding   # port and endpoint should match launcher.config   ProxyPass /paraview http://localhost:9000/paraview   # Handle WebSocket forwarding   RewriteEngine On   # This is the path the mapping file Jetty creates   # path to proxy should match launcher.config   RewriteMap session-to-port txt:<apache-root>/proxy.txt   # This is the rewrite condition. Look for anything with a sessionId= in the   # query part of the URL and capture the value to use below.   RewriteCond %{QUERY_STRING} ^sessionId=(.*)&path=(.*)$ [NC]   # This does the rewrite using the mapping file and the sessionId   RewriteRule ^/proxy.*$  ws://${session-to-port:%1}/%2  [P] </VirtualHost>

Save the <apache-root>\conf\extra\httpd-vhosts.conf file and:

• create the folder(s): <paraview-root>\log\apache2
• create an empty file named proxy.txt in the <apache-root> directory
• open the <apache-root>\conf\httpd.conf file and enable (uncomment) the following modules:
  
  • vhost_alias
  • proxy
  • proxy_http
  • proxy_wstunnel
  • rewrite
    
• open the C:\Windows\System32\drivers\etc\hosts file and add an entry for paraview:
  

127.0.0.1            paraview <your-ip-address>    paraview

Creating the ParaView Web Launcher configurationOnce the virtual hosts have been setup, the ParaView Web launcher configuration needs to be created so the requests for ParaView Web are processed appropriately. To do this, create a file named launcher.config in the ParaView installation directory. (<paraview-root>\launcher.config). The content of the file is as follows:

{   "configuration": {     "host" : "localhost",     "port" : 9000,     "endpoint": "paraview",   "content": "<paraview-root>/share/paraview-5.2/web/visualizer/www",     "proxy_file" : "<apache-root>/proxy.txt",     "sessionURL" : "ws://paraview:80/proxy?sessionId=${id}&path=ws",     "timeout" : 30,     "log_dir" : "<paraview-root>/log/",     "fields" : []   },   "resources" : [ {   "host" : "localhost",   "port_range" : [9001, 9999]   } ],   "properties" : {     "python_exec" : "<paraview-root>/bin/pvpython.exe",     "visualizer": "<paraview-root>/share/paraview-5.2/web/visualizer/server/pvw-visualizer.py"   },   "apps": {     "visualizer": {         "cmd": [             "${python_exec}", "-dr", "${visualizer}", "--port", "${port}", "--authKey", "${secret}",  "--data", "${dataDir}", "--load-file", "${dataFile}"         ],         "ready_line" : "Starting factory"     }   } }

Modify the index.htmlAdd the following script to the <paraview-root>\share\paraview-5.2\web\visualizer\www\index.html file (replace the existing script):

<script>      function getFileToLoad() {     var directoryPath = window.name;     var filename = directoryPath.split('\\').slice(-1).join('\\');     var directory = directoryPath.substring(0, directoryPath.indexOf(filename));     return {       dataFile:filename,       dataDir:directory     };   };   Visualizer.connect({       application: 'visualizer',       dataFile: getFileToLoad().dataFile,       dataDir: getFileToLoad().dataDir   });   Visualizer.autoStopServer(10); </script>

In the above script, the following properties are being passed:

• dataFile - the name of the file to be rendered in the Visualizer
• dataDir - the location of the data directory under which the data file(s) are present
  

If the dataDir location is fixed then it can be hard coded in the script, and only the dataFile name needs to be passed. In such a case, the following script should be used:

// grab the parameter from the URL function getUrlParameter(name) {   name = name.replace(/[\[]/, '\\[').replace(/[\]]/, '\\]');   var regex = new RegExp('[\\?&]' + name + '=([^&#]*)');   var results = regex.exec(location.search);   return results === null ? '' : decodeURIComponent(results[1].replace(/\+/g, ' ')); }; Visualizer.connect({   application: 'visualizer',   dataFile: getUrlParameter('data'),   dataDir: 'C:\\SomeFolder\\Data\\Files' });

The URL to invoke this would be: http://paraview/?data=can.ex2
Starting up from the command lineOpen a command prompt to run each of the following:

• Start the apache httd server by running: <apache-root>\bin\httpd.exe
• Create a launcher script (launcher.bat) to start the ParaView Web Server with the following commands:
  

set PV_HOME=<paraview-root> %PV_HOME%\bin\pvpython.exe %PV_HOME%\bin\Lib\site-packages\vtk\web\launcher.py %PV_HOME%\launcher.config

Run launcher.bat file