dulwich.protocol module

Generic functions for talking the git smart server protocol.

class dulwich.protocol.BufferedPktLineWriter(write, bufsize=65515)

Bases: object

Writer that wraps its data in pkt-lines and has an independent buffer.

Consecutive calls to write() wrap the data in a pkt-line and then buffers it until enough lines have been written such that their total length (including length prefix) reach the buffer size.

Initialize the BufferedPktLineWriter.

Parameters

  • write – A write callback for the underlying writer.

  • bufsize – The internal buffer size, including length prefixes.

flush()

Flush all data from the buffer.

write(data)

Write data, wrapping it in a pkt-line.

class dulwich.protocol.PktLineParser(handle_pkt)

Bases: object

Packet line parser that hands completed packets off to a callback.

get_tail()

Read back any unused data.

parse(data)

Parse a fragment of data and call back for any completed packets.

class dulwich.protocol.Protocol(read, write, close=None, report_activity=None)

Bases: object

Class for interacting with a remote git process over the wire.

Parts of the git wire protocol use ‘pkt-lines’ to communicate. A pkt-line consists of the length of the line as a 4-byte hex string, followed by the payload data. The length includes the 4-byte header. The special line ‘0000’ indicates the end of a section of input and is called a ‘flush-pkt’.

For details on the pkt-line format, see the cgit distribution:

Documentation/technical/protocol-common.txt

close()
eof()

Test whether the protocol stream has reached EOF.

Note that this refers to the actual stream EOF and not just a flush-pkt.

Returns: True if the stream is at EOF, False otherwise.

read_cmd()

Read a command and some arguments from the git client

Only used for the TCP git protocol (git://).

Returns: A tuple of (command, [list of arguments]).

read_pkt_line()

Reads a pkt-line from the remote git process.

This method may read from the readahead buffer; see unread_pkt_line.

Returns: The next string from the stream, without the length prefix, or

None for a flush-pkt (‘0000’).

read_pkt_seq()

Read a sequence of pkt-lines from the remote git process.

Returns: Yields each line of data up to but not including the next

flush-pkt.

send_cmd(cmd, *args)

Send a command and some arguments to a git server.

Only used for the TCP git protocol (git://).

Parameters

  • cmd – The remote service to access.

  • args – List of arguments to send to remove service.

unread_pkt_line(data)

Unread a single line of data into the readahead buffer.

This method can be used to unread a single pkt-line into a fixed readahead buffer.

Parameters

data – The data to unread, without the length prefix.

Raises

ValueError – If more than one pkt-line is unread.

write_pkt_line(line)

Sends a pkt-line to the remote git process.

Parameters

line – A string containing the data to send, without the length prefix.

write_sideband(channel, blob)

Write multiplexed data to the sideband.

Parameters

  • channel – An int specifying the channel to write to.

  • blob – A blob of data (as a string) to send on this channel.

class dulwich.protocol.ReceivableProtocol(recv, write, close=None, report_activity=None, rbufsize=8192)

Bases: Protocol

Variant of Protocol that allows reading up to a size without blocking.

This class has a recv() method that behaves like socket.recv() in addition to a read() method.

If you want to read n bytes from the wire and block until exactly n bytes (or EOF) are read, use read(n). If you want to read at most n bytes from the wire but don’t care if you get less, use recv(n). Note that recv(n) will still block until at least one byte is read.

read(size)
recv(size)
dulwich.protocol.ack_type(capabilities)

Extract the ack type from a capabilities list.

dulwich.protocol.agent_string()
dulwich.protocol.capability_agent()
dulwich.protocol.capability_symref(from_ref, to_ref)
dulwich.protocol.extract_capabilities(text)

Extract a capabilities list from a string, if present.

Parameters

text – String to extract from

Returns: Tuple with text with capabilities removed and list of capabilities

dulwich.protocol.extract_capability_names(capabilities)
dulwich.protocol.extract_want_line_capabilities(text)

Extract a capabilities list from a want line, if present.

Note that want lines have capabilities separated from the rest of the line by a space instead of a null byte. Thus want lines have the form:

want obj-id cap1 cap2 …

Parameters

text – Want line to extract from

Returns: Tuple with text with capabilities removed and list of capabilities

dulwich.protocol.format_ack_line(sha, ack_type=b'')
dulwich.protocol.format_capability_line(capabilities)
dulwich.protocol.format_cmd_pkt(cmd, *args)
dulwich.protocol.format_ref_line(ref, sha, capabilities=None)
dulwich.protocol.format_shallow_line(sha)
dulwich.protocol.format_unshallow_line(sha)
dulwich.protocol.parse_capability(capability)
dulwich.protocol.parse_cmd_pkt(line)
dulwich.protocol.pkt_line(data)

Wrap data in a pkt-line.

Parameters

data – The data to wrap, as a str or None.

Returns: The data prefixed with its length in pkt-line format; if data was

None, returns the flush-pkt (‘0000’).

dulwich.protocol.symref_capabilities(symrefs)