feat: simplify HTTP client proxy pools and authenticated JSON calls

2026-09-26 15:28:19 +08:00
parent 068e85132f
commit 96e7d9629b
27 changed files with 1611 additions and 143 deletions
--- a/httpc/json.go
+++ b/httpc/json.go
@@ -0,0 +1,119 @@
+package httpc
+
+import (
+	"bytes"
+	"context"
+	"encoding/json"
+	"errors"
+	"io"
+	"net/http"
+	"time"
+)
+
+// JSON bounds response memory, closes the body, and decodes only 2xx responses.
+// Optional headers/limits belong to this call and never alter the client.
+// output=nil discards a bounded stream; it does not buffer or validate JSON.
+// Empty successful bodies leave output unchanged. StatusError contains no body.
+func (c *Client) JSON(ctx context.Context, method, url string, input, output any, options ...RequestOption) error {
+	if ctx == nil {
+		return errors.New("httpc: nil context")
+	}
+	if c.closed.Load() {
+		return ErrClosed
+	}
+	if err := ctx.Err(); err != nil {
+		return err
+	}
+	settings := requestOptions{maxResponseBytes: c.config.MaxResponseBytes}
+	if len(options) > 0 {
+		var err error
+		settings, err = jsonOptions(c.config.MaxResponseBytes, options)
+		if err != nil {
+			return err
+		}
+	}
+	var body io.Reader
+	if input != nil {
+		data, err := json.Marshal(input)
+		if err != nil {
+			return err
+		}
+		body = bytes.NewReader(data)
+	}
+	request, err := http.NewRequestWithContext(ctx, method, url, body)
+	if err != nil {
+		return err
+	}
+	if settings.headers != nil {
+		request.Header = settings.headers
+	}
+	if input != nil {
+		if _, exists := request.Header["Content-Type"]; !exists {
+			request.Header.Set("Content-Type", "application/json")
+		}
+	}
+	response, err := c.Do(request)
+	if err != nil {
+		return err
+	}
+	defer response.Body.Close()
+	if response.StatusCode < 200 || response.StatusCode >= 300 {
+		drainStatusBody(response, settings.maxResponseBytes)
+		return &StatusError{StatusCode: response.StatusCode}
+	}
+	if response.ContentLength > settings.maxResponseBytes {
+		return ErrResponseTooLarge
+	}
+	limited := io.LimitReader(response.Body, settings.maxResponseBytes+1)
+	if output == nil {
+		count, err := io.Copy(io.Discard, limited)
+		if err != nil {
+			return err
+		}
+		if count > settings.maxResponseBytes {
+			return ErrResponseTooLarge
+		}
+		return nil
+	}
+	data, err := io.ReadAll(limited)
+	if err != nil {
+		return err
+	}
+	if int64(len(data)) > settings.maxResponseBytes {
+		return ErrResponseTooLarge
+	}
+	if len(bytes.TrimSpace(data)) == 0 {
+		return nil
+	}
+	return json.Unmarshal(data, output)
+}
+
+// A known small status body may still be slow. Spend at most a short grace
+// period trying to retain the connection, then cancel the HTTP read. The status
+// remains authoritative and the deferred Close still owns body cleanup.
+func drainStatusBody(response *http.Response, limit int64) {
+	if response.ContentLength < 0 || response.ContentLength > min(limit, 32<<10) {
+		return
+	}
+	body, ok := response.Body.(*responseBody)
+	if !ok {
+		return
+	}
+	timer := time.AfterFunc(25*time.Millisecond, body.cancel)
+	defer timer.Stop()
+	drainSmallBody(response, limit)
+}
+
+// Keep the option builder out of the allocation path of existing plain calls.
+func jsonOptions(limit int64, options []RequestOption) (requestOptions, error) {
+	settings := requestOptions{maxResponseBytes: limit}
+	for _, option := range options {
+		if option == nil {
+			return requestOptions{}, errors.New("httpc: nil request option")
+		}
+		if err := option(&settings); err != nil {
+			return requestOptions{}, err
+		}
+	}
+	return settings, nil
+}