WebChat for .net running on Medium trust server

[Waz]

Hi Narcis

Your app failed as well. Same fault as my app. However last night after battling a bit with example of Webchart I got the example working and therefore it is not the server that is at fault here. So the question is why does a new web chart fail when published to this website and the example works?

Please see fault attached. If you guys require some credentials to publish to this site please let me know so you can test. I have currently finished my app using MSChart however MSChart at the moment doesn't cater for the options that TeeChart has and I also would like to use gauges in my chart which currently I can't see how MSChart would do that. Only started using MSChart yesterday though. I also want to extend my license as it expires at end of this month and this is the only thing holding me back now.
Another thing that might cause issues, but I don't think this would be a problem is that I publish the site to my local IIS and copy the files to the website. The rest of the website works fine and so does MSChart, but not sure how the licensing would cope. I have tried once publishing directly to the website, but it takes over 2 hours then and it didn't work.

By the way thanks for the effort. I am going to be a little busy till thursday, but will continue testing during the evenings.

[Narcís]

Hi Waz,

The error message "required permissions cannot be aquired" seems to imply that the security level of the IIS application is not sufficient for the elements included in the application, in this case TeeChart. We published the test app here locally and then copied the folder to a remote server and added a new IIS Application to the folder location. The project worked successfully first. Point to note is that the default security for the share on that machine is 'full'. Editing those permissions down to 'high' or 'medium' would cause a failure with a similar error message to the one you quote.

To check that go to '.NET Trust Levels' of your IIS share and move the security up to 'Full'.

There are some notes on this issue here:
http://forums.asp.net/p/1051433/2383855.aspx
and a slightly alternative approach (not tried it) here:
http://social.msdn.microsoft.com/forums ... b3f2c4364e

[Waz]

Hi Narcis

The issue is that the server is not controlled by me. This is a medium trust server like the heading of the post is.I cannot adjust the trust levels as this is a international standard for servers. I already know how to change my local trust from FULL(Default) to medium and so forth, but the issue is that the ISP runs his server with medium trust and does not allow changes in the web.config file. This is to protect the other hundreds of users using this server. Full trust is the most dangerous level of security and thats why this server runs as a medium trust server. Please can we come to a solution for this TeeChart. MsChart can do it without hassle.

[Narcís]

Hi Waz,

We are looking at the issue to see what we can do, we'll report back to this thread.

As a footnote. If TeeChart.dll is added to the GAC in the server in question then a full trust level is automatically assigned. Is it possible for you to add TeeChart to the GAC in the server machine?

[Marc]

Hello Waz,

To summarise on the checks we've made.

- TeeChart is a strong named assembly and includes the assembly attribute 'AllowPartiallyTrustedCallers' (APTC). That complies with requirements for use in a medium trust ASP.NET environment _provided_ that the TeeChart.dll is in the GAC. We've tested and confirmed that for TeeChart. The same rule applies to any other strong named assembly that you might wish to reference from an ASP.NET application.

MSChart is in the GAC by default with Framework 4.0. Even for earlier than v4 installs, your ISP most likely has Microsoft System.Web.DataVisualization assemblies in the GAC (Framework 3.5) via a Microsoft update install. That can be confirmed by using gacutil to check from the VSNET command prompt (ie. gacutil /l System.Web.DataVisualization).

We recommend that TeeChart be installed in the GAC on the ISP server.

For further reference there's a conversation here that you might find of interest:
http://bytes.com/topic/asp-net/answers/ ... ed-callers

Regards,
Marc Meumann

[Waz]

Hi Marc and Narcis

Thanks for the reply. This is what I thought in the beginning when I was told it was a license issue. I already spoke to the ISP back then and they have told me they will not install this on their servers. I am going to try go to someone higher in the organisation to try get this done.

Just a small question though. Can I just give them the dll or will they have to install the full teechart.
If it's possible just to send me a small description(Step by step) of what they need to do so I can relay the message and we can get this sorted as quick as possible.

Thanks for the assistance.

[Marc]

Hello Waz,

Sorry, after further tests this still isn't conclusive yet. The initial tests in the design environment worked to the model described (trust level and GAC). The published one doesn't (yet). Please leave that with us a little longer so that we can supply you with all definitive steps. It may be that TeeChart contains some element that simply isn't going to comply with straightforward 'medium' rights on publish. We'd prefer to have that completely clear before you go back to your ISP.

Apologies once again for the delay.
Regards,
Marc

[Waz]

Hi Marc

Ok Thanks. I would prefer to not touch the ISP server. We are also considering running our own local Server instead of using the ISP however if it's possible to get TeeChart working on the ISP server without adjusting the server side then this would be better for me. I have come up with some major issues(Alot of wasted programming time) on the MSChart side as well that with TeeChart is simple to do so currently I'm going to stop developing with MSChart and hope you can come up with a solution for me.

Thanks for the assistance.
Again if you guys need to test on the ISP server I have no issues giving you a folder to test on the server with some credentials.

[Waz]

Hi guys

Any luck with this yet?

[Marc]

Hello Waz,

The status is this:

The early test we made didn't give the correct results because the test environment wasn't 'clean' enough to reproduce the ISP type environment. Further tests proved TeeChart reliance on a higher than medium trust level. We're working through exactly what TeeChart uses/does that requires anything more than medium trust and looking to see whether we can change that requirement.

TeeChart's WebChart uses Serialization classes to save the designtime state (Chart characteristics as modified by the Chart Editor) as a base64 string in the WebChart tag. That is then deserialized at runtime. Use of Microsoft's De/Serialization classes requires full trust, hence the problem. We're looking to see whether we can modify TeeChart to unhook reliance on Serialization.

This work is taking some time and results are not yet proven but hopefully I can give you more feedback very soon.

Regards,
Marc

[Waz]

Thanks Marc

[Waz]

Hi Guys

Hope all is well! We looking to purchase a new license for this app and for future apps however I need to know if this is going to be possible for future webservers. If you still working on the issue then it's not a problem as the project will only take early next year, but would just need to know that there will be a solution.

Keep well

[Marc]

Hello Waz,

Sorry not to have a definitive answer for you yet. We'll try and get this to you for Friday - to be able to say whether we consider it viable for us to make the WebChart medium trust compatible or not. The sticking point is how much internal functionality is affected by compatibility in relation to functionality that the product delivers.

Regards,
Marc

[Marc]

Hello Waz,

We think we've isolated all the factors involved and have successfully tested a version of WebChart in a medium trust environment without the requirement of TeeChart in the GAC. We're working on a few options to bypass some limitations and hopefully we can make a test version available to you within a few days.

Regards,
Marc