Rendering to Memory

07-13-2007, 4:35 PM
Hello, I want to render a report to memory (in my case as PDF), such that I may open it up with a separate PDF library, modify it and stream it out from there, all without ever having to write something to disk. In looking at the DataDynamics.Reports.Rendering.IO, I only see a single provider (FileStreamProvider). Please tell me there is, or soon will be, some way to stream an export to something other than a file... this is a critical issue to us. Thanks for any info!

Re: Rendering to Memory

07-13-2007, 6:01 PM
Currently, we only provide the FileStreamProvider out of the box for use in your own code; however, the FileStreamProvider inherits from an abstract class called StreamProvider.  This abstract class is the type that the Render method is looking for. So you can implement your own StreamProvider that uses a MemoryStream in its implementation.

I've attached a solution that contains a sample implementation that you can use.  I have also entered suggestion CR 25229 and attached your e-mail address to it, this CR is to have us provide another StreamProvider based on the MemoryStream.

HTH,

James

Re: Rendering to Memory

07-14-2007, 10:04 AM
Hi James,

Ok, I used the sample you attached and was able to call Render, using that new Stream provider. However, when the Render method is complete, the CanRead property of the Stream is "false", meaning I guess I can't read from it, so it's basically useless. Perhaps this is just a limitation of my coding skills, but how can I get to the data that's been written to the memory stream after the Render method is called?

Re: Rendering to Memory

07-14-2007, 1:13 PM

Once the report is rendered you can make a few method calls to get the data back from the memory stream.

MemoryStreamInfo memoryStreamInfo = streamProvider.GetPrimaryStream() as MemoryStreamInfo;
if( memoryStreamInfo != null ) 
{
    MemoryStream memoryStream = memoryStreamInfo.Open() as MemoryStream;
 
    byte [] data = memoryStream.ToArray();
    // data now contains all of the data that was written to the stream
    // you can then use this as-is, or base another memory stream off it
    // MemoryStream renderedStream = new MemoryStream( data );
}

HTH,

James

Re: Rendering to Memory

06-27-2008, 4:11 PM
I'm using this technique to render a report that has a master report defined. The master report is in the same directory as the report I'm rendering and the master report isn't rendering. (IE, its just rendering the report that uses the master but without the master report)

Do I need to do something special to make it work? I tried using MergeWithMaster() even though it says for internal use only but that doesn't seem to do it either.

Note: Rendering to PDF using a memory stream DOES include the master with no problems but rending to HTML does not.

Re: Rendering to Memory

06-27-2008, 5:02 PM
You must ensure that the MasterReport property has the correct path to the MasterReport. Calling Render on a ReportRuntime should automatically merge master and content reports.

See the attached sample for an example.


If you have any more questions, feel free to ask.

Thanks,
Jon

Re: Rendering to Memory

06-27-2008, 5:19 PM
Thank you for the example you provided.
FileInfo masterReportFile = new FileInfo(@"C:\ClientTrack.NET\Customer\Data Systems\Reports\ClientTrack.rdlx-master");
if (!masterReportFile.Exists)
{
throw new Exception("Noob!");
}
ddlRD.Report.MasterReport = masterReportFile.FullName;

Exception is not thrown and as before, it renders fine as PDF but when rendered as HTML using this memorystream technique referanced in this thread the master report is not applied to the HTML version.

Re: Rendering to Memory

06-27-2008, 5:31 PM
Rendering to HTML using the default FileStreamProvider does the same thing, no master applied. PDF still fine using both memorystream and filestream.

Re: Rendering to Memory

06-27-2008, 5:38 PM
Similar, possibly related, issue. My master report has embedded images but the report I'm playing with that uses the master does not.

DataDynamics.Reports.ReportDefinition ddlRD = new DataDynamics.Reports.ReportDefinition(new FileInfo(ReportPath));
DataDynamics.Reports.ReportRuntime ddrRT = new DataDynamics.Reports.ReportRuntime(ddlRD);

FileInfo masterReportFile = new FileInfo(@"C:\ClientTrack.NET\Customer\Data Systems\Reports\ClientTrack.rdlx-master");
if (!masterReportFile.Exists)
{//Paranoidly proving the file exists on the hardcoded path that I know is correct.
throw new Exception("Noob!");
}
//Before assignment, MasterReport="ClientTrack.rldx-master"; Said master is in same folder as the report.
ddlRD.Report.MasterReport = masterReportFile.FullName;

ddlRD.Report.EmbeddedImages.Count==0

IE, the EmbeddedImages collection isn't seeing the images that are embedded in my master report, thus I can't swap them out even in PDF which I can render with the master.

Re: Rendering to Memory

06-30-2008, 12:57 PM
I have entered Case 111310 in regards to the issue with the HTML Rendering Extension not outputting page headers and page footers when it renderings in Galley Mode (its default rendering mode).

For your issue with the Master report's EmbeddedImages, they are not supposed to be editable from the content report, this is by design. I think the best option in this case would be to create a theme file for each of your customers and embed the images there.


If you have any more questions, feel free to ask.

Thanks,
Jon

Re: Rendering to Memory

06-30-2008, 1:22 PM
A couple of questions on that one. A good number of our customers just run with the canned reports we ship with (and our low volume customers we don't even give the option of authoring reports but they still want their own logo). As a result generating a custom theme by hand of each of our customers is not an idea I like really at all. At the moment, deploying a new customer is pushbutton + uploading their custom logo which we apply all kinds of places. Adding "Create Custom Theme for reports that embeds customer logo" would be another task our implementation support team would probably hate me for.

Is the master supplied content completely non-editable via the report object model?

There are two things in the master I want to dynamically change for the report runtime:
1) Swapping logos (changing the image in the panel in the master). If I can't change the embedded images, is it at least possible to address the picture element and change its source?
2) Dynamically adding some TextBoxes containing parameters.

Is the only way to do this is to not use master reports at all? This being the case, I'll need to change my approach to not use master reports and assess if we can/should use DD. Then again there are no master reports at all in AR (we dynamically add all the header stuff at runtime with code) so it should be swallowable. I just need to do a bit more work.

Re: Rendering to Memory

06-30-2008, 4:37 PM
Well, what you could do is dynamically generate a Theme file when the user uploads the image. This could then be stored on the server somewhere and then be tied to the customer's profile somehow. Once the generated theme is tied to the customer, a custom implementation of the ResourceLocator could be used to provide the correct theme file to the master report.

Currently it is not possible to change the ReportDefinition's ResourceLocator in the latest public build, therefore, I will send you an email with a link to an interim build with this functionality as well as a sample project which demonstrates a basic implementation of a custom resource locator.


If you have any more questions, feel free to ask.

Thanks,
Jon

Re: Rendering to Memory

06-30-2008, 4:50 PM
Hang on, dont go to the effort yet, trying a different strategy at the moment, i'll let you know if it works.