the state of CGI

[aart-jan]

I have built and run several websites including forms running on the internet toolkit G web server. Unfortunately this is a real antiquated http server with some major limitations and bugs. :headbang: Still, I know of a couple of projects I would really like to outfit with a web interface. I would love to run labview VI, dll or exe files in CGI of another web server (such as Apache or even IIS).

Does anyone know of any Perl script or something to make other web servers talk to Labview CGI code?

Or maybe someone has an awsome alternative?

Aart-Jan

[Grampa_of_Oliva_n_Eden]

QUOTE(aart-jan @ Sep 27 2007, 07:43 AM)

I have built and run several websites including forms running on the internet toolkit G web server. Unfortunately this is a real antiquated http server with some major limitations and bugs. :headbang: Still, I know of a couple of projects I would really like to outfit with a web interface. I would love to run labview VI, dll or exe files in CGI of another web server (such as Apache or even IIS).

Does anyone know of any Perl script or something to make other web servers talk to Labview CGI code?

Or maybe someone has an awsome alternative?

Aart-Jan

I am facing another Web-based app as well. I was concidering using LV as the back end and use standard stuff to handle the web-access. But Since I am weak in the web-support area, I would alos like to hear what poeple have to say to help aart-jan.

Ben

[Rolf Kalbermatter]

QUOTE(Ben @ Sep 27 2007, 07:53 AM)

I am facing another Web-based app as well. I was concidering using LV as the back end and use standard stuff to handle the web-access. But Since I am weak in the web-support area, I would alos like to hear what poeple have to say to help aart-jan.

Long ago I did look into this also in combination to interface to external script servers like Python for instance. One idea I came up is to use the LabVIEW TCP/IP VI server interface directly (instead of going through it's Active X interface which would limit the solution to Windows LabVIEW hosts only). I could access this interface through direct TCP/IP sockets in LabVIEW 6.1 but eventually run into some problems to access the Call by Reference interface (nothing that couldn't be overcome but the flattening of the typedescriptor and the different parameters is a real headache to get right and requires a lot of inside research into the LabVIEW datatype storage model (almost fully documented in an older App Note). I eventually stopped development on this because of several reasons.

- My Library was for ease of testing and debugging written in LabVIEW. Not very useful really considering that you can much more easily use VI Server directly and converting this interface to another language like C, Python, etc would still be quite an undertaking.

- NI obviously never documented that protocol for some reasons. One of them is that they change it between LabVIEW versions albeit not extremely. But the introduction of the 32bit safe typedescriptors in LabVIEW 8 certainly must have had a profound impact on that protocol although I never looked into that. Support of the entire (private) LabVIEW object hierarchy through this interface in LabVIEW 7 should probably also have made some impact here.

In general I concluded this interface to have great potential but its undocumented nature and version dependant changes make it basically unsuitable to rely upon for any serious project. And for just some fiddling around it is way to much work to develop and maintain such a solution in any language I could imagine.

But it would be quite feasable to create a LabVIEW DLL/shared lib that wraps the important VI Server methods and functions into exported functions and access that from any host that is capable to call into shared libraries. You would have one DLL/shared lib per platform you want to access LabVIEW from but since VI server is network TCP/IP based that would not have to be the machine that is running the actual LabVIEW target VI.

Rolf Kalbermatter

[siva]

Try the (Alpha Version) PERL-LabVIEW Communication Tool available here, http://jeffreytravis.com/lost/download/LVperl.zip

QUOTE(aart-jan @ Sep 27 2007, 05:13 PM)

I have built and run several websites including forms running on the internet toolkit G web server. Unfortunately this is a real antiquated http server with some major limitations and bugs. :headbang: Still, I know of a couple of projects I would really like to outfit with a web interface. I would love to run labview VI, dll or exe files in CGI of another web server (such as Apache or even IIS).

Does anyone know of any Perl script or something to make other web servers talk to Labview CGI code?

Or maybe someone has an awsome alternative?

Aart-Jan