keel/net/http/middleware/gzip_test.go

package middleware_test

import (
	"bytes"
	"compress/gzip"
	"io"
	"net/http"
	"strings"
	"testing"

	stdhttp "github.com/foomo/gostandards/http"
	"github.com/foomo/keel/keeltest"
	"github.com/foomo/keel/net/http/middleware"
	"github.com/stretchr/testify/assert"
	"github.com/stretchr/testify/require"
)

const (
	gzipPayload1023 = "Lorem ipsum dolor sit amet, consetetur sadipscing elitr, sed diam nonumy eirmod tempor invidunt ut labore et dolore magna aliquyam erat, sed diam voluptua. At vero eos et accusam et justo duo dolores et ea rebum. Stet clita kasd gubergren, no sea takimata sanctus est Lorem ipsum dolor sit amet. Lorem ipsum dolor sit amet, consetetur sadipscing elitr, sed diam nonumy eirmod tempor invidunt ut labore et dolore magna aliquyam erat, sed diam voluptua. At vero eos et accusam et justo duo dolores et ea rebum. Stet clita kasd gubergren, no sea takimata sanctus est Lorem ipsum dolor sit amet. Lorem ipsum dolor sit amet, consetetur sadipscing elitr, sed diam nonumy eirmod tempor invidunt ut labore et dolore magna aliquyam erat, sed diam voluptua. At vero eos et accusam et justo duo dolores et ea rebum. Stet clita kasd gubergren, no sea takimata sanctus est Lorem ipsum dolor sit amet. \n\nDuis autem vel eum iriure dolor in hendrerit in vulputate velit esse molestie consequat, vel illum dolore eu feugiat nulla facilisisd"
	gzipPayload1024 = "Lorem ipsum dolor sit amet, consetetur sadipscing elitr, sed diam nonumy eirmod tempor invidunt ut labore et dolore magna aliquyam erat, sed diam voluptua. At vero eos et accusam et justo duo dolores et ea rebum. Stet clita kasd gubergren, no sea takimata sanctus est Lorem ipsum dolor sit amet. Lorem ipsum dolor sit amet, consetetur sadipscing elitr, sed diam nonumy eirmod tempor invidunt ut labore et dolore magna aliquyam erat, sed diam voluptua. At vero eos et accusam et justo duo dolores et ea rebum. Stet clita kasd gubergren, no sea takimata sanctus est Lorem ipsum dolor sit amet. Lorem ipsum dolor sit amet, consetetur sadipscing elitr, sed diam nonumy eirmod tempor invidunt ut labore et dolore magna aliquyam erat, sed diam voluptua. At vero eos et accusam et justo duo dolores et ea rebum. Stet clita kasd gubergren, no sea takimata sanctus est Lorem ipsum dolor sit amet. \n\nDuis autem vel eum iriure dolor in hendrerit in vulputate velit esse molestie consequat, vel illum dolore eu feugiat nulla facilisisda"
)

func TestGzip(t *testing.T) {
	svr := keeltest.NewServer()

	// get logger
	l := svr.Logger()

	var payload string

	svr.AddService(
		keeltest.NewServiceHTTP(l, "demo",
			http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
				// validate request headers
				assert.Empty(t, r.Header.Get(stdhttp.HeaderContentEncoding.String()))
				assert.Equal(t, stdhttp.EncodingGzip.String(), r.Header.Get(stdhttp.HeaderAcceptEncoding.String()))

				// validate request body
				body, err := io.ReadAll(r.Body)
				assert.NoError(t, err)
				assert.Equal(t, payload, string(body))

				// response
				_, _ = w.Write(body)
			}),
			middleware.GZip(),
		),
	)

	svr.Start()

	url := svr.GetService("demo").URL() + "/"

	// send payload < 1024
	t.Run("<1024", func(t *testing.T) {
		payload = gzipPayload1023
		body, err := gzipString(payload)
		require.NoError(t, err)

		// send gzip request
		req, err := http.NewRequestWithContext(svr.Context(), http.MethodPost, url, bytes.NewReader(body))
		require.NoError(t, err)
		req.Header.Set(stdhttp.HeaderAcceptEncoding.String(), stdhttp.EncodingGzip.String())
		req.Header.Set(stdhttp.HeaderContentEncoding.String(), stdhttp.EncodingGzip.String())

		resp, err := http.DefaultClient.Do(req)
		require.NoError(t, err)
		defer resp.Body.Close()

		// validate response header
		assert.Equal(t, http.StatusOK, resp.StatusCode)
		// validate response body
		respBody, err := io.ReadAll(resp.Body)
		require.NoError(t, err)
		assert.Equal(t, payload, string(respBody))
	})

	// send payload > 1024
	t.Run(">=1024", func(t *testing.T) {
		payload = gzipPayload1024
		body, err := gzipString(payload)
		require.NoError(t, err)

		// send gzip request
		req, err := http.NewRequestWithContext(svr.Context(), http.MethodPost, url, bytes.NewReader(body))
		require.NoError(t, err)
		req.Header.Set(stdhttp.HeaderAcceptEncoding.String(), stdhttp.EncodingGzip.String())
		req.Header.Set(stdhttp.HeaderContentEncoding.String(), stdhttp.EncodingGzip.String())

		resp, err := http.DefaultClient.Do(req)
		require.NoError(t, err)
		defer resp.Body.Close()

		// validate response header
		assert.Equal(t, http.StatusOK, resp.StatusCode)
		assert.Equal(t, stdhttp.EncodingGzip.String(), resp.Header.Get(stdhttp.HeaderContentEncoding.String()))
		// validate response body
		respBody, err := io.ReadAll(resp.Body)
		require.NoError(t, err)
		respBodyDecompressed, err := gunzipString(respBody)
		require.NoError(t, err)
		assert.Equal(t, payload, string(respBodyDecompressed))
	})
}

func TestGZipBadRequest(t *testing.T) {
	svr := keeltest.NewServer()

	// get logger
	l := svr.Logger()

	svr.AddService(
		keeltest.NewServiceHTTP(l, "demo",
			http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {}),
			middleware.GZip(),
		),
	)

	svr.Start()

	url := svr.GetService("demo").URL() + "/"

	req, err := http.NewRequestWithContext(svr.Context(), http.MethodPost, url, strings.NewReader("hello"))
	require.NoError(t, err)

	req.Header.Set(stdhttp.HeaderContentEncoding.String(), stdhttp.EncodingGzip.String())
	resp, err := http.DefaultClient.Do(req)
	require.NoError(t, err)
	assert.Equal(t, http.StatusBadRequest, resp.StatusCode)
	defer resp.Body.Close()
}

func gzipString(body string) ([]byte, error) {
	var buf bytes.Buffer
	gz := gzip.NewWriter(&buf)

	_, err := gz.Write([]byte(body))
	if err != nil {
		return nil, err
	}

	if err := gz.Close(); err != nil {
		return nil, err
	}

	return buf.Bytes(), nil
}

func gunzipString(body []byte) ([]byte, error) {
	gr, err := gzip.NewReader(bytes.NewReader(body))
	if err != nil {
		return nil, err
	}
	defer gr.Close()

	var buf bytes.Buffer
	_, err = io.Copy(&buf, gr) //nolint:gosec
	if err != nil {
		return nil, err
	}

	return buf.Bytes(), nil
}