func ExampleScanner() {
// A reader is needed as input.
input := strings.NewReader("000ahello\n" +
"000bworld!\n" +
"0000",
)
// Create the scanner...
s := pktline.NewScanner(input)
// and scan every pkt-line found in the input.
for s.Scan() {
payload := s.Bytes()
if len(payload) == 0 { // zero sized payloads correspond to flush-pkts.
fmt.Println("FLUSH-PKT DETECTED\n")
} else { // otherwise, you will be able to access the full payload.
fmt.Printf("PAYLOAD = %q\n", string(payload))
}
}
// this will catch any error when reading from the input, if any.
if s.Err() != nil {
fmt.Println(s.Err())
}
// Output:
// PAYLOAD = "hello\n"
// PAYLOAD = "world!\n"
// FLUSH-PKT DETECTED
}
func (s *SuiteScanner) TestEmptyReader(c *C) {
r := strings.NewReader("")
sc := pktline.NewScanner(r)
hasPayload := sc.Scan()
c.Assert(hasPayload, Equals, false)
c.Assert(sc.Err(), Equals, nil)
}
// Decode reads from the given reader and decodes a report-status message. It
// does not read more input than what is needed to fill the report status.
func (s *ReportStatus) Decode(r io.Reader) error {
scan := pktline.NewScanner(r)
if err := s.scanFirstLine(scan); err != nil {
return err
}
if err := s.decodeReportStatus(scan.Bytes()); err != nil {
return err
}
flushed := false
for scan.Scan() {
b := scan.Bytes()
if isFlush(b) {
flushed = true
break
}
if err := s.decodeCommandStatus(b); err != nil {
return err
}
}
if !flushed {
return fmt.Errorf("missing flush")
}
return scan.Err()
}
func (s *SuiteScanner) TestScanAndPayload(c *C) {
for _, test := range [...]string{
"a",
"a\n",
strings.Repeat("a", 100),
strings.Repeat("a", 100) + "\n",
strings.Repeat("\x00", 100),
strings.Repeat("\x00", 100) + "\n",
strings.Repeat("a", pktline.MaxPayloadSize),
strings.Repeat("a", pktline.MaxPayloadSize-1) + "\n",
} {
var buf bytes.Buffer
e := pktline.NewEncoder(&buf)
err := e.EncodeString(test)
c.Assert(err, IsNil,
Commentf("input len=%x, contents=%.10q\n", len(test), test))
sc := pktline.NewScanner(&buf)
c.Assert(sc.Scan(), Equals, true,
Commentf("test = %.20q...", test))
obtained := sc.Bytes()
c.Assert(obtained, DeepEquals, []byte(test),
Commentf("in = %.20q out = %.20q", test, string(obtained)))
}
}
func (s *SuiteScanner) TestPktLineTooShort(c *C) {
r := strings.NewReader("010cfoobar")
sc := pktline.NewScanner(r)
c.Assert(sc.Scan(), Equals, false)
c.Assert(sc.Err(), ErrorMatches, "unexpected EOF")
}
func (s *SuiteScanner) TestEOF(c *C) {
var buf bytes.Buffer
e := pktline.NewEncoder(&buf)
err := e.EncodeString("first", "second")
c.Assert(err, IsNil)
sc := pktline.NewScanner(&buf)
for sc.Scan() {
}
c.Assert(sc.Err(), IsNil)
}
// Decode reads the next update-request message form the reader and wr
func (req *ReferenceUpdateRequest) Decode(r io.Reader) error {
var rc io.ReadCloser
var ok bool
rc, ok = r.(io.ReadCloser)
if !ok {
rc = ioutil.NopCloser(r)
}
d := &updReqDecoder{r: rc, s: pktline.NewScanner(r)}
return d.Decode(req)
}
func (s *SuiteScanner) TestFlush(c *C) {
var buf bytes.Buffer
e := pktline.NewEncoder(&buf)
err := e.Flush()
c.Assert(err, IsNil)
sc := pktline.NewScanner(&buf)
c.Assert(sc.Scan(), Equals, true)
payload := sc.Bytes()
c.Assert(len(payload), Equals, 0)
}
// NewDemuxer returns a new Demuxer for the given t and read from r
func NewDemuxer(t Type, r io.Reader) *Demuxer {
max := MaxPackedSize64k
if t == Sideband {
max = MaxPackedSize
}
return &Demuxer{
t: t,
r: r,
max: max,
s: pktline.NewScanner(r),
}
}
func (s *SuiteScanner) TestInvalid(c *C) {
for _, test := range [...]string{
"0001", "0002", "0003", "0004",
"0001asdfsadf", "0004foo",
"fff1", "fff2",
"gorka",
"0", "003",
" 5a", "5 a", "5 \n",
"-001", "-000",
} {
r := strings.NewReader(test)
sc := pktline.NewScanner(r)
_ = sc.Scan()
c.Assert(sc.Err(), ErrorMatches, pktline.ErrInvalidPktLen.Error(),
Commentf("data = %q", test))
}
}
// A section are several non flush-pkt lines followed by a flush-pkt, which
// how the git protocol sends long messages.
func (s *SuiteScanner) TestReadSomeSections(c *C) {
nSections := 2
nLines := 4
data := sectionsExample(c, nSections, nLines)
sc := pktline.NewScanner(data)
sectionCounter := 0
lineCounter := 0
for sc.Scan() {
if len(sc.Bytes()) == 0 {
sectionCounter++
}
lineCounter++
}
c.Assert(sc.Err(), IsNil)
c.Assert(sectionCounter, Equals, nSections)
c.Assert(lineCounter, Equals, (1+nLines)*nSections)
}
func (s *SuiteScanner) TestSkip(c *C) {
for _, test := range [...]struct {
input []string
n int
expected []byte
}{
{
input: []string{
"first",
"second",
"third"},
n: 1,
expected: []byte("second"),
},
{
input: []string{
"first",
"second",
"third"},
n: 2,
expected: []byte("third"),
},
} {
var buf bytes.Buffer
e := pktline.NewEncoder(&buf)
err := e.EncodeString(test.input...)
c.Assert(err, IsNil)
sc := pktline.NewScanner(&buf)
for i := 0; i < test.n; i++ {
c.Assert(sc.Scan(), Equals, true,
Commentf("scan error = %s", sc.Err()))
}
c.Assert(sc.Scan(), Equals, true,
Commentf("scan error = %s", sc.Err()))
obtained := sc.Bytes()
c.Assert(obtained, DeepEquals, test.expected,
Commentf("\nin = %.20q\nout = %.20q\nexp = %.20q",
test.input, obtained, test.expected))
}
}
// Decode decodes the response into the struct, isMultiACK should be true, if
// the request was done with multi_ack or multi_ack_detailed capabilities
func (r *ServerResponse) Decode(reader io.Reader, isMultiACK bool) error {
if isMultiACK {
return errors.New("multi_ack and multi_ack_detailed are not supported")
}
s := pktline.NewScanner(reader)
for s.Scan() {
line := s.Bytes()
if err := r.decodeLine(line); err != nil {
return err
}
if !isMultiACK {
break
}
}
return s.Err()
}
func (r *ShallowUpdate) Decode(reader io.Reader) error {
s := pktline.NewScanner(reader)
for s.Scan() {
line := s.Bytes()
var err error
switch {
case bytes.HasPrefix(line, shallow):
err = r.decodeShallowLine(line)
case bytes.HasPrefix(line, unshallow):
err = r.decodeUnshallowLine(line)
case bytes.Compare(line, pktline.Flush) == 0:
return nil
}
if err != nil {
return err
}
}
return s.Err()
}
func newAdvRefsDecoder(r io.Reader) *advRefsDecoder {
return &advRefsDecoder{
s: pktline.NewScanner(r),
}
}
func newUlReqDecoder(r io.Reader) *ulReqDecoder {
return &ulReqDecoder{
s: pktline.NewScanner(r),
}
}
func (s *SuiteScanner) TestInternalReadError(c *C) {
sc := pktline.NewScanner(&mockReader{})
c.Assert(sc.Scan(), Equals, false)
c.Assert(sc.Err(), ErrorMatches, "foo")
}
