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semantic-kernel/python/samples
Dmytro Struk 18d9a8e8b2 Python: .Net: Updated encoding logic in prompt templates (#12983)
### Motivation and Context

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Resolves: https://github.com/microsoft/semantic-kernel/issues/11821

Today, the encoding of template arguments is performed only if argument
type is `string`. In case of custom type, anonymous type or collection -
the encoding is not performed.

This PR contains changes to throw an exception in case if encoding is
enabled but complex type is used. In case of complex type, the encoding
should be performed manually according to business logic and automatic
encoding should be explicitly disabled.

This enforces stricter, but more secure template rendering rules.

**Note**: this is a breaking change for customers who use Handlebars or
Liquid template with complex type arguments. Code changes are required
when initializing template arguments:
```diff
var arguments = new KernelArguments()
{
    { "customer", new
        {
-             firstName = userInput.FirstName,
-             lastName = userInput.LastName,
+             firstName = HttpUtility.HtmlEncode(userInput.FirstName),
+             lastName = HttpUtility.HtmlEncode(userInput.LastName),
        }
    }
};

var templateFactory = new LiquidPromptTemplateFactory();
var promptTemplateConfig = new PromptTemplateConfig()
{
    TemplateFormat = "liquid"
+   InputVariables = new()
+   {
+       // We set AllowDangerouslySetContent to 'true' because each property of this argument is encoded manually. 
+       new() { Name = "customer", AllowDangerouslySetContent = true },
+   }
};

var promptTemplate = templateFactory.Create(promptTemplateConfig);
var renderedPrompt = await promptTemplate.RenderAsync(kernel, arguments); 
```

### Contribution Checklist

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raises no violations
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- [ ] I didn't break anyone 😄
2025-08-26 22:09:00 -07:00
..

Semantic Kernel Samples

Type Description
getting_started Take this step by step tutorial to get started with Semantic Kernel and get introduced to the key concepts.
getting_started_with_agents Take this step by step tutorial to get started with Semantic Kernel Agents and get introduced to the key concepts.
getting_started_with_processes Take this step by step tutorial to get started with Semantic Kernel Processes and get introduced to the key concepts.
concepts This section contains focused samples which illustrate all of the concepts included in Semantic Kernel.
demos Look here to find a sample which demonstrate how to use many of Semantic Kernel features.
learn_resources Code snippets that are related to online documentation sources like Microsoft Learn, DevBlogs and others