CRE-1319

Author: mchain0

pkg/http/http.go

@@ -10,6 +10,18 @@ import (
 	"github.com/smartcontractkit/chainlink-common/pkg/logger"
 )
 
+type noOpResponseWriter struct{}
+
+func (w *noOpResponseWriter) Header() http.Header {
+	return http.Header{}
+}
+
+func (w *noOpResponseWriter) Write(b []byte) (int, error) {
+	return len(b), nil
+}
+
+func (w *noOpResponseWriter) WriteHeader(statusCode int) {}
+
 type clientConfig interface {
 	URL() url.URL // DatabaseURL
 }
@@ -72,7 +84,10 @@ func (h *Request) SendRequestReader() (responseBody io.ReadCloser, statusCode in
 	elapsed := time.Since(start)
 	logger.Sugared(h.Logger).Tracew(fmt.Sprintf("http adapter got %v in %s", statusCode, elapsed), "statusCode", statusCode, "timeElapsedSeconds", elapsed)
 
-	source := http.MaxBytesReader(nil, r.Body, h.Config.SizeLimit)
+	var source io.ReadCloser = r.Body
+	if h.Config.SizeLimit > 0 {
+		source = http.MaxBytesReader(&noOpResponseWriter{}, r.Body, h.Config.SizeLimit)
+	}
 
 	return source, statusCode, r.Header, nil
 }

pkg/http/http_test.go

@@ -55,3 +55,31 @@ func (t *mockTransport) RoundTrip(req *netHttp.Request) (*netHttp.Response, erro
 	response.Body = io.NopCloser(strings.NewReader(responseBody))
 	return response, nil
 }
+
+func TestSendRequestReader_WithSizeLimit(t *testing.T) {
+	t.Parallel()
+
+	client := NewUnrestrictedClient()
+	client.Transport = newMockTransport()
+
+	netReq, err := netHttp.NewRequestWithContext(t.Context(), "GET", "http://localhost", bytes.NewReader([]byte{}))
+	assert.NoError(t, err)
+
+	req := &Request{
+		Client:  client,
+		Request: netReq,
+		Config:  RequestConfig{SizeLimit: 100},
+		Logger:  logger.Nop(),
+	}
+
+	reader, statusCode, headers, err := req.SendRequestReader()
+	assert.NoError(t, err)
+	assert.Equal(t, 200, statusCode)
+	assert.Equal(t, "application/json", headers.Get("Content-Type"))
+
+	// Verify reader works
+	body, err := io.ReadAll(reader)
+	assert.NoError(t, err)
+	assert.Equal(t, `{"foo":123}`, string(body))
+	assert.NoError(t, reader.Close())
+}