Azure B2C custom policy – a powerful tool for identity and access management. But, have you ever struggled with trimming claims in your Azure B2C custom policy? If yes, you’re not alone! Trimming claims is an essential step in customizing your Azure B2C experience, and today, we’re going to break it down for you in simple, easy-to-follow steps.
What are Claims in Azure B2C?
Before we dive into trimming claims, let’s quickly cover what claims are in Azure B2C. In Azure B2C, claims are pieces of information about a user that are passed between the identity provider (IdP) and the application. These claims can include things like a user’s name, email address, and birthdate. Claims are used to identify a user and provide additional information about them to the application.
Why Trim Claims?
So, why do we need to trim claims in Azure B2C? Well, there are a few reasons:
- Security: Trimming claims helps to reduce the risk of exposing sensitive information about your users.
- Performance: Trimming claims can improve the performance of your Azure B2C custom policy by reducing the amount of data being passed around.
- Customization: Trimming claims allows you to customize the information that is passed to your application, giving you more control over the user experience.
Trimming Claims in Azure B2C Custom Policy
Now that we’ve covered the why, let’s get to the how! Trimming claims in Azure B2C custom policy involves using the `ClaimsTransformation` element to manipulate the claims that are passed to the application. Here’s an example of how to trim a claim:
<ClaimsTransformation>
<TransformationName>TrimClaim</TransformationName>
<InputClaims>
<InputClaim ClaimTypeReferenceId="givenName" TransformationClaimType="inputClaim"/>
</InputClaims>
<OutputClaims>
<OutputClaim ClaimTypeReferenceId="trimmedGivenName" TransformationClaimType="outputClaim"/>
</OutputClaims>
<Parameters>
<Parameter Id="maxLength">10</Parameter>
</Parameters>
</ClaimsTransformation>
In this example, we’re using the `ClaimsTransformation` element to trim the `givenName` claim to a maximum length of 10 characters. The `InputClaims` element specifies the input claim that we want to manipulate, and the `OutputClaims` element specifies the output claim that we want to produce. The `Parameters` element specifies the maximum length that we want to trim the claim to.
Using the `ClaimsTransformation` Element
The `ClaimsTransformation` element is the heart of trimming claims in Azure B2C custom policy. Here’s a breakdown of the elements that make up the `ClaimsTransformation` element:
| Element | Description |
|---|---|
| TransformationName | The name of the claims transformation. |
| InputClaims | The input claims that are used in the transformation. |
| OutputClaims | The output claims that are produced by the transformation. |
| Parameters | The parameters that are used in the transformation. |
Trimming Claims with Azure B2C Custom Policy: A Step-by-Step Guide
Now that we’ve covered the basics of trimming claims in Azure B2C custom policy, let’s walk through a step-by-step guide on how to trim a claim:
-
Step 1: Identify the Claim to Trim
Identify the claim that you want to trim. In this example, we’ll use the `givenName` claim.
-
Step 2: Create a ClaimsTransformation Element
Create a `ClaimsTransformation` element in your Azure B2C custom policy file.
-
Step 3: Specify the InputClaim
Specify the input claim that you want to manipulate using the `InputClaims` element.
-
Step 4: Specify the OutputClaim
Specify the output claim that you want to produce using the `OutputClaims` element.
-
Step 5: Specify the Parameters
Specify the parameters that you want to use in the transformation using the `Parameters` element.
-
Step 6: Add the ClaimsTransformation Element to Your Policy
Add the `ClaimsTransformation` element to your Azure B2C custom policy file.
-
Step 7: Test Your Policy
Test your Azure B2C custom policy to ensure that the claim is being trimmed correctly.
BONUS: Trimming Multiple Claims at Once
Sometimes, you may need to trim multiple claims at once. Azure B2C custom policy makes this easy by allowing you to specify multiple `InputClaims` elements within a single `ClaimsTransformation` element. Here’s an example:
<ClaimsTransformation>
<TransformationName>TrimClaims</TransformationName>
<InputClaims>
<InputClaim ClaimTypeReferenceId="givenName" TransformationClaimType="inputClaim"/>
<InputClaim ClaimTypeReferenceId="surName" TransformationClaimType="inputClaim"/>
</InputClaims>
<OutputClaims>
<OutputClaim ClaimTypeReferenceId="trimmedGivenName" TransformationClaimType="outputClaim"/>
<OutputClaim ClaimTypeReferenceId="trimmedSurName" TransformationClaimType="outputClaim"/>
</OutputClaims>
<Parameters>
<Parameter Id="maxLength">10</Parameter>
</Parameters>
</ClaimsTransformation>
In this example, we’re trimming both the `givenName` and `surName` claims to a maximum length of 10 characters.
Conclusion
Trimming claims in Azure B2C custom policy is a powerful way to customize the user experience and improve security and performance. By following the steps outlined in this guide, you should be able to trim claims with ease. Remember to test your policy thoroughly to ensure that the claims are being trimmed correctly.
Happy coding!
Here are 5 Questions and Answers about “How can I trim Claim in Azure B2C Custom Policy”:
Frequently Asked Question
Get ready to master the art of trimming claims in Azure B2C Custom Policy! 🎉
What is claim trimming and why is it necessary in Azure B2C Custom Policy?
Claim trimming is the process of reducing the number of claims sent in the token response, which helps to improve performance, reduce token size, and enhance security. It’s necessary in Azure B2C Custom Policy because it allows you to control the claims that are included in the token, ensuring that only the necessary information is shared with the client application.
How can I trim claims using Azure B2C Custom Policy?
You can trim claims by using the `OutputClaim` element in your Azure B2C Custom Policy. This element allows you to specify the claims that should be included in the token response. You can also use the `AlwaysIncludeClaim` attribute to include claims that are not otherwise included by default.
What are the different types of claims that can be trimmed in Azure B2C Custom Policy?
There are several types of claims that can be trimmed in Azure B2C Custom Policy, including Identity Claims (e.g., email, name), Strong Authentication Claims (e.g., MFA), and Application Claims (e.g., custom attributes).
Can I trim claims dynamically based on user input or other conditions in Azure B2C Custom Policy?
Yes, you can trim claims dynamically based on user input or other conditions using Azure B2C Custom Policy’s advanced features, such as conditional statements, input claims, and output claims. This allows you to create a more customized and flexible claim trimming experience.
What are some best practices to keep in mind when trimming claims in Azure B2C Custom Policy?
Some best practices to keep in mind when trimming claims in Azure B2C Custom Policy include minimizing the number of claims sent in the token response, avoiding sensitive information, and testing your policy thoroughly to ensure that the expected claims are included.
