Optimizations of the validation process

[tsutomi]

This pull request focuses on eliminating duplicate message validation logic across all major connectors (Twilio SMS, Twilio WhatsApp, SendGrid Email) and centralizing validation in the base connector class. It also updates the MediaContent type to use a more appropriate content type and adjusts related tests. These changes improve performance, maintainability, and consistency in message validation, while cleaning up redundant code in connector implementations.

Validation Centralization and Connector Refactoring

• Removed duplicate message validation logic from SendMessageCoreAsync in TwilioSmsConnector, TwilioWhatsAppConnector, and SendGridEmailConnector, ensuring validation is only performed once in the base class (ChannelConnectorBase.SendMessageAsync). [1] [2] [3]
• Updated the validation flow in ChannelConnectorBase.ValidateMessageCoreAsync to delegate all validation to the schema, covering message ID, endpoints, content type, and properties.
• Removed the obsolete ValidateMessageProperties extension method from ChannelSchemaExtensions, further enforcing centralized validation.
• Added a detailed action plan in VALIDATION_DUPLICATION_FIX_ACTION_PLAN.md outlining the rationale, steps, testing, risks, and success criteria for the validation refactor.

Media Content Type Update

• Changed the ContentType of MediaContent from Binary to Media for better semantic accuracy.
• Updated all related unit tests to expect MessageContentType.Media instead of Binary for media content. [1] [2] [3] [4] [5] [6] [7]

Minor Enhancements

• Added a static factory method Endpoint.Create(IEndpoint? endpoint) to simplify endpoint conversions.

[Copilot]

Pull Request Overview

This pull request focuses on eliminating duplicate message validation logic across all major connectors (Twilio SMS, Twilio WhatsApp, SendGrid Email) and centralizing validation in the base connector class. It also updates the MediaContent type to use a more appropriate content type and adjusts related tests to use actual framework classes instead of test helpers.

• Removed duplicate validation calls from concrete connector implementations, relying on centralized validation in ChannelConnectorBase
• Changed MediaContent.ContentType from Binary to Media for better semantic accuracy
• Replaced custom test helper classes with actual framework classes (Message, Endpoint, TextContent, etc.) across all test files

Reviewed Changes

Copilot reviewed 27 out of 27 changed files in this pull request and generated 1 comment.

Show a summary per file

File	Description
TwilioWhatsAppConnector.cs	Removed duplicate validation logic from SendMessageCoreAsync method
TwilioSmsConnector.cs	Removed duplicate validation logic from SendMessageCoreAsync method
SendGridEmailConnector.cs	Removed duplicate validation logic from SendMessageCoreAsync method
MediaContent.cs	Changed ContentType from Binary to Media
Test files	Replaced test helper classes with actual framework classes and updated assertions
ChannelSchemaExtensions.cs	Removed obsolete ValidateMessageProperties method
ChannelConnectorBase.cs	Updated ValidateMessageCoreAsync to use centralized schema validation
Documentation files	Added comprehensive action plan and architecture documentation