feat: Add support for extension headers on client side

[guglielmo-san]

Description

This PR implements the support for extensions on client side

Fixes #170 🦕

Release-As: 0.3.6

[gemini-code-assist]

Summary of Changes

Hello @guglielmo-san, I'm Gemini Code Assist¹! I'm currently reviewing this pull request and will post my feedback shortly. In the meantime, here's a summary to help you and other reviewers quickly get up to speed!

This pull request significantly enhances the client-side capabilities by introducing a robust interception framework and explicit support for extension headers. The new interceptor pattern allows for greater control and customization of client-server interactions, while the extension header support enables more flexible communication protocols. These changes improve the extensibility and adaptability of the client library.

Highlights

• Client-side Interceptors: Introduced a new interception mechanism allowing custom logic to be executed before and after client method calls. This enables modification of requests, responses, and options, as well as early returns.
• Extension Headers Support: Added explicit support for extension headers on the client side, allowing clients to specify a list of extension URIs that will be included in HTTP requests.
• Refactored RequestOptions: The RequestOptions interface has been moved and enhanced to include extensions and a context map, providing more flexibility for request customization.
• Comprehensive Interceptor Testing: New tests have been added to validate the interceptor functionality, covering various scenarios including request/response modification, early exits, and interception of streaming calls.

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[gemini-code-assist]

Code Review

This pull request introduces a powerful interceptor mechanism for client-side calls, which is a great addition for extensibility. The implementation is well-structured, with clear separation of concerns in the new interceptors.ts file and good test coverage for the new functionality. I've found a few areas for improvement: one is a minor API design suggestion to make RequestOptions.context optional, another is a bug fix for the non-streaming fallback in sendMessageStream where after interceptors were not being called, and finally a suggestion to refactor some duplicated code in the streaming methods to improve maintainability. Overall, this is a solid contribution.

[guglielmo-san]

/gemini review

[gemini-code-assist]

Code Review

This pull request adds support for extension headers on the client side. The changes include updating the RequestOptions interface, adding helper functions to generate and parse extension headers, and integrating this logic into the JsonRpcTransport. A new test file is also added to verify the functionality. The implementation is solid, but I have identified a potential bug in the header parsing logic and a minor improvement for type safety in the tests. Overall, great work on implementing this feature.

[guglielmo-san]

/gemini review

[gemini-code-assist]

Code Review

This pull request introduces support for client-side extension headers. It adds a serviceParameters option to requests, which is then used by the JSON-RPC transport to include custom headers. The response headers are also parsed for activated extensions. The changes are well-tested. I've found one potential issue regarding the order of properties when constructing request headers, which could lead to important headers being unintentionally overridden. My review includes a suggestion to fix this.