Add rate limiting support

[ejsmith]

No description provided.

[CLAassistant]

All committers have signed the CLA.

[niemyjski]

Overall looks good. I'm wondering how I would use a middleware to update existing rate limit config based on header values for both rate limit remaining and reate limit reset time

[ejsmith]

Overall looks good. I'm wondering how I would use a middleware to update existing rate limit config based on header values for both rate limit remaining and reate limit reset time

I don't really see it as something we should be updating dynamically. You can do that by just going to the provider.rateLimiter.config but this is just really meant more to keep us from DoS ourselves due to bad reactive code.

[niemyjski]

Our api returns the rare limit in real time, would be nice to use that. Also some routes are not rate limited.

[ejsmith]

Yeah, that would be kind of nice to respond to that. Although, wasn't it just for posting events?

[Copilot]

Pull Request Overview

This PR adds support for rate limiting by introducing a new RateLimiter class and middleware, integrating it across the provider and helper APIs, and updating documentation and tests accordingly.

• Added RateLimiter class and createRateLimitMiddleware in src/RateLimiter.ts
• Integrated rate limiting into FetchClientProvider and DefaultHelpers
• Expanded tests, exports in mod.ts, documentation in readme.md, and updated build/config files

Reviewed Changes

Copilot reviewed 10 out of 11 changed files in this pull request and generated 1 comment.

Show a summary per file

File	Description
src/RateLimiter.ts	New rate limiter implementation and middleware
src/RateLimiter.test.ts	Unit tests for limiting logic and middleware behavior
src/FetchClientProvider.ts	Added enableRateLimit method and provider integration
src/FetchClient.test.ts	Updated Zod import and schema type for zod/mini
src/DefaultHelpers.ts	Exposed global enableRateLimit helper
scripts/build.ts	Removed importMap from build configuration
readme.md	Documented rate limiting in README
mod.ts	Exported RateLimitConfig and RateLimiter
deno.json	Bumped dependency versions
.github/copilot-instructions.md	Added Copilot instructions

Comments suppressed due to low confidence (4)

src/RateLimiter.ts:159

• The getTimeUntilNextRequest method isn't covered by existing tests; add unit tests to verify that it returns correct millisecond durations and integrates with the Retry-After header.

  public getTimeUntilNextRequest(): number {

src/FetchClientProvider.ts:201

• [nitpick] Consider returning this from enableRateLimit to allow method chaining (e.g., provider.enableRateLimit(...).useMiddleware(...)).

  public enableRateLimit(config: RateLimitConfig) {

readme.md:10

• [nitpick] The table entry uses lowercase 'Rate limiting' while the section header is 'Rate Limiting'; consider matching the capitalization for consistency.

* [Rate limiting](#rate-limiting)

[Copilot]

The clone method currently throws a generic error; consider implementing a proper clone or removing this unimplemented stub to avoid runtime failures if clone() is used.

Suggested change

	throw new Error("Not implemented");
	return {
	...context.response,
	headers: new Headers(context.response.headers),
	problem: context.response.problem
	? { ...context.response.problem }
	: null,
	json: () => Promise.resolve({ ...context.response.problem }),
	text: () => Promise.resolve(JSON.stringify(context.response.problem)),
	arrayBuffer: () => Promise.resolve(new ArrayBuffer(0)),
	bytes: () => Promise.resolve(new Uint8Array()),
	blob: () => Promise.resolve(new Blob()),
	formData: () => Promise.resolve(new FormData()),
	clone: context.response.clone, // Reference the same clone method
	};

[niemyjski]

Yeah, that would be kind of nice to respond to that. Although, wasn't it just for posting events?

We rate limit every endpoint but a few: https://github.com/exceptionless/Exceptionless/blob/main/src/Exceptionless.Web/Utility/Handlers/ThrottlingMiddleware.cs#L107

[ejsmith]

Closing this one in favor of #3

[niemyjski]

should we delete this branch or are you looking at it?