Hallucinate a limited http client

go.mod

@@ -1,3 +1,5 @@
 module git.site.quack-lab.dev/dave/cyutils
 
 go 1.23.6
+
+require golang.org/x/time v0.12.0

go.sum

@@ -0,0 +1,2 @@
+golang.org/x/time v0.12.0 h1:ScB/8o8olJvc+CQPWrK3fPZNfh7qgwCrY0zJmoEQLSE=
+golang.org/x/time v0.12.0/go.mod h1:CDIdPxbZBQxdj6cxyCIdrNogrJKMJ7pr37NYpMcMDSg=

main.go

@@ -1,7 +1,11 @@
 package cyutils
 
 import (
+	"net/http"
 	"sync"
+	"time"
+
+	"golang.org/x/time/rate"
 )
 
 func WithWorkers[T any](workers int, arr []T, fn func(worker int, item T)) {
@@ -40,3 +44,39 @@ func Batched[T any](arr []T, batchSize int, fn func(batch []T)) {
 		fn(batch)
 	}
 }
+
+type RateLimitedTransport struct {
+	base    http.RoundTripper // Underlying transport
+	limiter *rate.Limiter     // Rate limiter
+}
+
+// RoundTrip enforces rate limiting before executing the request
+func (t *RateLimitedTransport) RoundTrip(req *http.Request) (*http.Response, error) {
+	ctx := req.Context()
+	if err := t.limiter.Wait(ctx); err != nil {
+		return nil, err // Handle context cancellation/timeout
+	}
+	return t.base.RoundTrip(req)
+}
+func LimitedHttp(rps float64, burst int, timeout time.Duration) *http.Client {
+	baseTransport := &http.Transport{
+		MaxIdleConns:        100,
+		MaxIdleConnsPerHost: 10,
+		IdleConnTimeout:     10 * time.Second,
+	}
+
+	// Initialize rate limiter
+	limiter := rate.NewLimiter(rate.Limit(rps), burst)
+
+	// Wrap transport with rate limiting
+	transport := &RateLimitedTransport{
+		base:    baseTransport,
+		limiter: limiter,
+	}
+
+	// Return configured client
+	return &http.Client{
+		Transport: transport,
+		Timeout:   timeout,
+	}
+}