TestWebsocketNetConn_LargeWrites tests that we can write large amounts of data thru the netconn in a single write. Without specifically setting the read limit, the websocket library limits the amount of data that can be read in a single message to 32kiB. Even after raising the limit, curiously, it
(t *testing.T)
| 19 | // the amount of data that can be read in a single message to 32kiB. Even after raising the limit, |
| 20 | // curiously, it still only reads 32kiB per Read(), but allows the large write to go thru. |
| 21 | func TestWebsocketNetConn_LargeWrites(t *testing.T) { |
| 22 | t.Parallel() |
| 23 | ctx := testutil.Context(t, testutil.WaitShort) |
| 24 | n := 4 * 1024 * 1024 // 4 MiB |
| 25 | svr := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) { |
| 26 | sws, err := websocket.Accept(w, r, nil) |
| 27 | if !assert.NoError(t, err) { |
| 28 | return |
| 29 | } |
| 30 | _, nc := codersdk.WebsocketNetConn(r.Context(), sws, websocket.MessageBinary) |
| 31 | defer nc.Close() |
| 32 | |
| 33 | // Although the writes are all in one go, the reads get broken up by |
| 34 | // the library. |
| 35 | j := 0 |
| 36 | b := make([]byte, n) |
| 37 | for j < n { |
| 38 | k, err := nc.Read(b[j:]) |
| 39 | if !assert.NoError(t, err) { |
| 40 | return |
| 41 | } |
| 42 | j += k |
| 43 | t.Logf("server read %d bytes, total %d", k, j) |
| 44 | } |
| 45 | assert.Equal(t, n, j) |
| 46 | j, err = nc.Write(b) |
| 47 | assert.Equal(t, n, j) |
| 48 | if !assert.NoError(t, err) { |
| 49 | return |
| 50 | } |
| 51 | })) |
| 52 | |
| 53 | // use of random data is worst case scenario for compression |
| 54 | cb := make([]byte, n) |
| 55 | rk, err := rand.Read(cb) |
| 56 | require.NoError(t, err) |
| 57 | require.Equal(t, n, rk) |
| 58 | |
| 59 | // nolint: bodyclose |
| 60 | cws, _, err := websocket.Dial(ctx, svr.URL, nil) |
| 61 | require.NoError(t, err) |
| 62 | _, cnc := codersdk.WebsocketNetConn(ctx, cws, websocket.MessageBinary) |
| 63 | ck, err := cnc.Write(cb) |
| 64 | require.NoError(t, err) |
| 65 | require.Equal(t, n, ck) |
| 66 | |
| 67 | cb2 := make([]byte, n) |
| 68 | j := 0 |
| 69 | for j < n { |
| 70 | k, err := cnc.Read(cb2[j:]) |
| 71 | if !assert.NoError(t, err) { |
| 72 | return |
| 73 | } |
| 74 | j += k |
| 75 | t.Logf("client read %d bytes, total %d", k, j) |
| 76 | } |
| 77 | require.NoError(t, err) |
| 78 | require.Equal(t, n, j) |