panamap-proto

Panamap-proto adds protobuf support to panamap object mapper.

Installation

Use the package manager pip to install panamap-proto.

pip install panamap

Usage

Initialize mapper

To enabe protobuf support you must pass ProtoMappingDescriptor in list to custom_descriptors parameter to Mapper constructor:

from panamap import Mapper
from panamap_proto import ProtoMappingDescriptor

mapper = Mapper(custom_descriptors=[ProtoMappingDescriptor])

After that you can set up mapping for protobuf generated classes.

Map classes

To map message Simple:

// messages.proto
syntax = "proto3";

message Simple {
    string value = 1;
}

You should use folowing configuration:

from panamap import Mapper
from panamap_proto import ProtoMappingDescriptor

from messages_pb2 import Simple

mapper = Mapper(custom_descriptors=[ProtoMappingDescriptor])

mapper.mapping(Simple, SimpleData).map_matching().register()

s = mapper.map(SimpleData("abc"), Simple)

print(s.value)
# 'abc'

Map enums

There is many ways to map python enums to protobuf generated enums, but the easiest way is to use values_map utility method:

// messages.proto
enum Lang {
    PYTHON = 0;
    CPP = 1;
    JAVA = 2;
}

from enum import Enum

from panamap import Mapper, values_map
from panamap_proto import ProtoMappingDescriptor

from messages_pb2 import Lang

class PyLang(Enum):
    PYTHON = 1
    CPP = 2
    JAVA = 3

mapper = Mapper(custom_descriptors=[ProtoMappingDescriptor])

pairs = [
    (PyLang.PYTHON, Lang.Value("PYTHON")),
    (PyLang.JAVA, Lang.Value("JAVA")),
    (PyLang.CPP, Lang.Value("CPP")),
]

mapper.mapping(PyLang, Lang) \
    .l_to_r_converter(values_map({py: proto for py, proto in pairs})) \
    .r_to_l_converter(values_map({proto: py for py, proto in pairs})) \
    .register()

Contributing

Contributing described in separate document.