Adding the httpu package

Signed-off-by: Dušan Mitrović <[email protected]>

Author: dusnm

constants/sizemultiples.go

@@ -0,0 +1,8 @@
+package constants
+
+const (
+	KiB = 1 << 10
+	MiB = 1 << 20
+	GiB = 1 << 30
+	TiB = 1 << 40
+)

httpu/httpu.go

@@ -0,0 +1,66 @@
+package httpu
+
+import (
+	"bytes"
+	"errors"
+	"io"
+	"net/http"
+	"strings"
+
+	"github.com/nano-interactive/go-utils/v2/constants"
+)
+
+var (
+	ErrNoRequestURL = errors.New("request url is empty")
+)
+
+func CurlFromRequest(request *http.Request) (string, error) {
+	if request.URL == nil {
+		return "", ErrNoRequestURL
+	}
+
+	var b strings.Builder
+	if request.Body == nil {
+		b.Grow(1 * constants.KiB)
+	} else {
+		// It's better to overestimate
+		// the amount of required memory
+		// than to not allocate enough.
+		b.Grow(1 * constants.MiB)
+	}
+
+	b.WriteString("curl -s -v -X ")
+	b.WriteString(request.Method)
+	b.WriteRune(' ')
+
+	for headerName, headerValues := range request.Header {
+		for _, headerValue := range headerValues {
+			b.WriteString("-H '")
+			b.WriteString(headerName)
+			b.WriteString(": ")
+			b.WriteString(headerValue)
+			b.WriteString("' ")
+		}
+	}
+
+	if request.Body != nil {
+		var buff bytes.Buffer
+		_, err := buff.ReadFrom(request.Body)
+		if err != nil {
+			return "", err
+		}
+
+		b.WriteString("-d '")
+		b.WriteString(buff.String())
+		b.WriteString("' ")
+
+		// reset the body after reading
+		request.Body = io.NopCloser(bytes.NewBuffer(buff.Bytes()))
+	}
+
+	b.WriteString("--compressed '")
+	b.WriteString(request.URL.String())
+	b.WriteString("'")
+
+	return b.String(), nil
+}

httpu/httpu_test.go

@@ -0,0 +1,83 @@
+package httpu_test
+
+import (
+	"bytes"
+	"io"
+	"net/http"
+	"net/url"
+	"testing"
+
+	"github.com/nano-interactive/go-utils/v2/httpu"
+	"github.com/stretchr/testify/assert"
+)
+
+func TestCurlFromRequest(t *testing.T) {
+	tests := []struct {
+		name     string
+		request  *http.Request
+		expected string
+		err      error
+	}{
+		{
+			name: "Valid GET request",
+			request: &http.Request{
+				Method: http.MethodGet,
+				URL:    &url.URL{Scheme: "http", Host: "example.com", Path: "/"},
+				Header: http.Header{
+					"User-Agent": []string{"test-agent"},
+				},
+			},
+			expected: "curl -s -v -X GET -H 'User-Agent: test-agent' --compressed 'http://example.com/'",
+			err:      nil,
+		},
+		{
+			name: "Valid POST request with body",
+			request: &http.Request{
+				Method: http.MethodPost,
+				URL:    &url.URL{Scheme: "http", Host: "example.com", Path: "/submit"},
+				Header: http.Header{
+					"Content-Type": []string{"application/json"},
+				},
+				Body: io.NopCloser(bytes.NewBufferString(`{"key":"value"}`)),
+			},
+			expected: "curl -s -v -X POST -H 'Content-Type: application/json' -d '{\"key\":\"value\"}' --compressed 'http://example.com/submit'",
+			err:      nil,
+		},
+		{
+			name: "Request with no URL",
+			request: &http.Request{
+				Method: http.MethodGet,
+				URL:    nil,
+			},
+			expected: "",
+			err:      httpu.ErrNoRequestURL,
+		},
+		{
+			name: "Request with multiple headers",
+			request: &http.Request{
+				Method: http.MethodGet,
+				URL:    &url.URL{Scheme: "http", Host: "example.com", Path: "/"},
+				Header: http.Header{
+					"User-Agent": []string{"test-agent"},
+					"Accept":     []string{"application/json", "text/html"},
+				},
+			},
+			expected: "curl -s -v -X GET -H 'User-Agent: test-agent' -H 'Accept: application/json' -H 'Accept: text/html' --compressed 'http://example.com/'",
+			err:      nil,
+		},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			result, err := httpu.CurlFromRequest(tt.request)
+
+			if tt.err != nil {
+				assert.Error(t, err)
+				assert.Equal(t, tt.err.Error(), err.Error())
+			} else {
+				assert.NoError(t, err)
+				assert.Equal(t, tt.expected, result)
+			}
+		})
+	}
+}