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cachingazureazure-web-roles

Graph rendering issue on Azure when multiple instance

I have developed chart rendering functionality in my web application and set following setting to store chart image in temp folder as per below

<add key="ChartImageHandler" value="deleteAfterServicing=false;Storage=file;Timeout=20;URL=~/TempCharts/"/>

It will work nice when we testing it in one instance only but when we will make more then one instance of web role then some chart rendering in some not, i think this is problem of multiple stack of server (multiple instance).

What is the solution to this for multiple instances?

Solution

  • did you develop the carting by your own, or you are using the ASP.NET chart controls? If you have your own, then you have a chance for success. In the options I see Storage=file. What are other options?

    Developing for Windows Azure your approach should be to use a BlobStorage. That way you can change your chart control to store the temporary image files into a Blob. More over, if you have full control over the user control you could make it write to the blob, and render the path to the image in the blob itself. You can point your own domain (name it images.mysite.com) the Azure Blob storage, then make the user control render directly that URL to the client (i.e. http://images.mysite.com/tempcharts/[guid].png).

    EDIT

    When the clarification about using ASP.NET Chart control is made, here are two solutions to successfully run ASP.NET Chart control in Windows Azure:

    1. Change config following this blog post.
    2. Implement your own HttpHandler for the chart.