Use interface to define http client instead using *http.Client

[mtavano]

I think resend package could define an interface for http client so it will be easier handle rate limit.

example:

package resend

type HTTPClient interface {
	Do(*http.Request) (*http.Response, error)
}

// Client handles communication with Resend API.
type Client struct {
	// HTTP client

	// proposal:
	client HTTPClient 

	// current:
	// client *http.Client

	// Api Key
	ApiKey string

	// .....
}


func NewCustomClient(httpClient HTTPClient, apiKey string) *Client {
    ...
 }

This makes it easier for each developer to handle rate limiting using the strategy that best fits their needs, while exposing only the required client method: .Do(req) (*res, error)

This way, I can plug in my own rate limiter via an interface instead of relying on a concrete pointer implementation.

example:

package impl

import (
    "net/http"

    "github.com/resend/resend-go"
    ratelimit "github.com/mtavano/devkito/clients/http"
)

func NewMailer(apiKey string, maxReq, windowSeconds int) *resend.Client {
    httpClient := ratelimit.NewClient(http.Options{
        MaxRequest: 2,
        WindowInSeconds: 1,
    }, http.DefaultClient)

    return resend.NewCustomClient(httpClient, apiKet)
}

I would like to help submitting the PR but havent seen any contribution guide.

That said, I’ll probably implement this in a fork anyway, since I don’t see an elegant way to achieve this without wrapping the entire package.

[drish]

i like this @mtavano