extprot 0.1.1

extprot is a compact, extensible and efficient binary serialization format.<br /><br />This is a python implementation of the 'extprot' serialization scheme, the details of which are descripted in detail at:<br /><br /> http://eigenclass.org/R2/writings/extprot-extensible-protocols-intro<br /><br />Similar to Google's Protocol Buffers and Apache Thrift, extprot allows the definition of structured data "messages". Messages are essentially a set of typed key-value pairs that can be efficiently serialized to/from a compact binary format, and are defined in a language-neutral "protocol" file. Here's a simple example of an extprot message:<br /><br /> message person = {<br /> id: int;<br /> name: string;<br /> emails: [ string ]<br /> }<br /><br />Here the 'person' message contains three fields: 'id' is an integer, 'name' is a string, and 'emails' is a list of strings. Such protocol descriptions are compiled into a set of Python classes that can be manipulated using standard syntax and idioms. If the above protocol is recorded in the file "person.proto", here's a simple example of how it might be used:<br /><br /> >>> extprot.import_protocol("person.proto",globals())<br /> >>> p1 = person(1,"Guido")<br /> >>> print p1.emails # fields use a sensible default if possible<br /> []<br /> >>> p1.emails.append("guido@python.org")<br /> >>> p1.emails.append(7) # all fields are dynamically typechecked<br /> Traceback (mosts recent call last):<br /> ...<br /> ValueError: not a valid String: 7<br /> >>> print repr(p1.to_string())<br /> 'x01x1fx03x00x02x03x05Guidox05x13x01x03x10guido@python.org'<br /> >>> print person.from_string(p1.to_string()).name<br /> 'Guido'<br /> >>><br /><br />Extprot compares favourably to related serialization technologies:<br /><br />* powerful type system; strongly-typed tuples and lists, tagged disjoint unions, parametric polymorphism.<br />* self-delimitng data; all serialized messages indicate their length, allowing easy streaming and skipping of messages.<br />* self-describing data; the 'skeleton' of a message can be reconstructed without having the protocol definition.<br />* compact binary format; comparable to protocol-buffers/thrift, but with some overhead due to self-delimiting nature.<br /><br />These features combine to make extprot strongly extensible, often allowing messages to maintain backward *and* forward compatibility across protocol extensions that include: adding fields to a message, adding elements to a tuple, adding cases to a disjoint union, and promoting a primitive type into a tuple, list or union.<br /><br />md5=f224b07d2242a17a1f2f6afe830ba676

Requirements:	No special requirements
Platforms:	*nix, Linux
Keyword:	Adding,  Allowing,  Binary,  Compact,  Definition,  Disjoint,  Extprot,  Extprot 0 1 1,  Fields,  Format,  Gtgtgt,  Message,  Messages,  Print,  Protocol,  Serialization,  Serialized,  Simple,  String,  Union
Users rating:	0/10