Merge proxy and options midelwares

internal/proxy/helpers.go

@@ -3,6 +3,9 @@ package proxy
 import (
 	"net/http"
 	"strings"
+
+	"github.com/evg4b/uncors/internal/responseprinter"
+	"github.com/pterm/pterm"
 )
 
 type modificationsMap = map[string]func(string) (string, error)
@@ -30,3 +33,23 @@ func copyHeaders(source, dest http.Header, modifications modificationsMap) error
 
 	return nil
 }
+
+func makeOptionsResponse(printer pterm.PrefixPrinter, writer http.ResponseWriter, req *http.Request) error {
+	header := writer.Header()
+	for key, values := range req.Header {
+		lowerKey := strings.ToLower(key)
+		if strings.Contains(lowerKey, "access-control-request") {
+			for _, value := range values {
+				transformedKey := strings.Replace(lowerKey, "request", "allow", 1)
+				header.Add(transformedKey, value)
+			}
+		}
+	}
+
+	printer.Printfln(responseprinter.PrintResponse(&http.Response{
+		StatusCode: http.StatusOK,
+		Request:    req,
+	}))
+
+	return nil
+}

internal/proxy/proxy.go

@@ -4,6 +4,7 @@ import (
 	"fmt"
 	"io"
 	"net/http"
+	"strings"
 
 	"github.com/evg4b/uncors/internal/processor"
 	"github.com/evg4b/uncors/internal/responseprinter"
@@ -37,6 +38,10 @@ func (pm *ProxyMiddleware) Wrap(_ processor.HandlerFunc) processor.HandlerFunc {
 	}
 
 	return func(resp http.ResponseWriter, req *http.Request) error {
+		if strings.EqualFold(req.Method, http.MethodOptions) {
+			return makeOptionsResponse(proxyWriter, resp, req)
+		}
+
 		targetR, sourceR, err := pm.replacerFactory.Make(req.URL)
 		if err != nil {
 			return fmt.Errorf("failed to transform general url: %w", err)

internal/proxy/proxy_test.go

@@ -12,6 +12,7 @@ import (
 	"github.com/evg4b/uncors/internal/proxy"
 	"github.com/evg4b/uncors/internal/urlreplacer"
 	"github.com/evg4b/uncors/pkg/urlx"
+	"github.com/evg4b/uncors/testing/mocks"
 	"github.com/evg4b/uncors/testing/testutils"
 	"github.com/stretchr/testify/assert"
 )
@@ -178,3 +179,71 @@ func TestProxyMiddlewareWrap(t *testing.T) {
 		)
 	})
 }
+
+func TestOptionsMiddlewareWrap(t *testing.T) {
+	middleware := proxy.NewProxyMiddleware()
+
+	t.Run("should handle OPTIONS request", func(t *testing.T) {
+		tracker := mocks.NewMiddlewaresTracker(t)
+		proc := processor.NewRequestProcessor(
+			processor.WithMiddleware(middleware),
+			processor.WithMiddleware(tracker.MakeFinalMiddleware("final")),
+		)
+
+		req, err := http.NewRequestWithContext(context.TODO(), http.MethodOptions, "/", nil)
+		testutils.CheckNoError(t, err)
+
+		proc.ServeHTTP(httptest.NewRecorder(), req)
+
+		assert.Equal(t, []string{}, tracker.CallsOrder)
+	})
+
+	t.Run("should correctly create response", func(t *testing.T) {
+		testMethods := []struct {
+			name     string
+			headers  http.Header
+			expected http.Header
+		}{
+			{
+				name:     "should do not change empty headers",
+				headers:  http.Header(map[string][]string{}),
+				expected: http.Header(map[string][]string{}),
+			},
+			{
+				name: "should do not skip not access-control-request-* headers",
+				headers: http.Header{
+					"Host":          {"www.host.com"},
+					"Content-Type":  {"application/json"},
+					"Authorization": {"Bearer Token"},
+				},
+				expected: http.Header{},
+			},
+			{
+				name: "should allow all access-control-request-* headers",
+				headers: http.Header{
+					"Access-Control-Request-Headers": {"X-PINGOTHER, Content-Type"},
+					"Access-Control-Request-Method":  {http.MethodPost, http.MethodDelete},
+				},
+				expected: http.Header{
+					"Access-Control-Allow-Headers": {"X-PINGOTHER, Content-Type"},
+					"Access-Control-Allow-Method":  {http.MethodPost, http.MethodDelete},
+				},
+			},
+		}
+		for _, testCase := range testMethods {
+			t.Run(testCase.name, func(t *testing.T) {
+				proc := processor.NewRequestProcessor(processor.WithMiddleware(middleware))
+				req, err := http.NewRequestWithContext(context.TODO(), http.MethodOptions, "/", nil)
+				testutils.CheckNoError(t, err)
+
+				req.Header = testCase.headers
+
+				recorder := httptest.NewRecorder()
+				proc.ServeHTTP(recorder, req)
+
+				assert.Equal(t, http.StatusOK, recorder.Code)
+				assert.Equal(t, testCase.expected, recorder.Header())
+			})
+		}
+	})
+}

main.go

@@ -10,7 +10,6 @@ import (
 	"strings"
 
 	"github.com/evg4b/uncors/internal/infrastructure"
-	"github.com/evg4b/uncors/internal/options"
 	"github.com/evg4b/uncors/internal/processor"
 	"github.com/evg4b/uncors/internal/proxy"
 	"github.com/evg4b/uncors/internal/urlreplacer"
@@ -67,14 +66,12 @@ func main() {
 		pterm.Fatal.Println(err)
 	}
 
-	optionsMiddleware := options.NewOptionsMiddleware()
 	proxyMiddleware := proxy.NewProxyMiddleware(
 		proxy.WithURLReplacerFactory(factory),
 		proxy.WithHTTPClient(httpClient),
 	)
 
 	requestProcessor := processor.NewRequestProcessor(
-		processor.WithMiddleware(optionsMiddleware),
 		processor.WithMiddleware(proxyMiddleware),
 	)