Using PFX files with MSAL for Certificate AuthType

[rodrigobr-msft]

This pull request updates the certificate-based authentication flow to use a single PFX certificate file instead of separate PEM and key files. This simplifies configuration and removes unnecessary dependencies. The changes also update the configuration class, its initialization, and related tests to reflect this new approach.

Certificate Authentication Refactor:

• Replaced usage of separate PEM and key files with a single PFX certificate file (CERT_PFX_FILE) in the AgentAuthConfiguration class and its initialization. All references to CERT_PEM_FILE and CERT_KEY_FILE have been removed and replaced with CERT_PFX_FILE. [1] [2] [3]
• Updated the MSAL authentication logic to use the PFX certificate file path (private_key_pfx_path) instead of loading and parsing PEM and key files, and removed the calculation of the certificate thumbprint.

Dependency Cleanup:

• Removed the cryptography library from the package dependencies and imports, as it is no longer needed for certificate parsing. [1] [2]

Test Updates:

• Updated tests to use the new cert_pfx_file parameter and to check for CERT_PFX_FILE instead of the old PEM/key fields. [1] [2] [3]

[Copilot]

Pull request overview

Refactors certificate-based authentication to use a single PFX file with MSAL, removing PEM/key handling and dropping the cryptography dependency.

Changes:

• Replace CERT_PEM_FILE/CERT_KEY_FILE configuration with CERT_PFX_FILE
• Update MSAL credential construction to use private_key_pfx_path
• Update unit tests and dependency list to match the new certificate flow

Reviewed changes

Copilot reviewed 4 out of 4 changed files in this pull request and generated 5 comments.

File	Description
tests/hosting_core/test_auth_configuration.py	Updates test inputs/assertions to validate CERT_PFX_FILE instead of PEM/key fields
libraries/microsoft-agents-hosting-core/microsoft_agents/hosting/core/authorization/agent_auth_configuration.py	Refactors configuration API and internal fields to support PFX-only certificate configuration
libraries/microsoft-agents-authentication-msal/setup.py	Removes cryptography dependency now that PEM parsing is gone
libraries/microsoft-agents-authentication-msal/microsoft_agents/authentication/msal/msal_auth.py	Switches MSAL client credential setup to reference a PFX file path

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[Copilot]

Pull request overview

Copilot reviewed 4 out of 4 changed files in this pull request and generated 3 comments.

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