Java
http://code.google.com/p/protobuf-java-format/
maven
<dependency>
<groupId>com.googlecode.protobuf-java-format</groupId>
<artifactId>protobuf-java-format</artifactId>
<version>1.2</version>
</dependency>
从protobuf转json
Message someProto =SomeProto.getDefaultInstance();
String jsonFormat =JsonFormat.printToString(someProto);
从json转protobuf
Message.Builder builder =SomeProto.newBuilder();
String jsonFormat = _load json document from a source_;
JsonFormat.merge(jsonFormat, builder);
C++
https://github.com/shramov/json2pb
Python
https://github.com/NextTuesday/py-pb-converters
导入模块pbjson.py即可使用。
ps. 原始模块的pb2json函数会自动过滤protobuf中字段值为空的数据。根据需要可注释掉过滤代码。
pbjson .py:
| import simplejson | |
|
from google.protobuf.descriptor import FieldDescriptor as FD |
|
|
class ConvertException(Exception): |
|
| pass | |
|
def dict2pb(cls, adict, strict=False): |
|
| """ | |
| Takes a class representing the ProtoBuf Message and fills it with data from | |
| the dict. | |
| """ | |
|
obj = cls() |
|
|
for field in obj.DESCRIPTOR.fields: |
|
|
if not field.label == field.LABEL_REQUIRED: |
|
| continue | |
|
if not field.has_default_value: |
|
| continue | |
|
if not field.name in adict: |
|
| raise ConvertException('Field "%s" missing from descriptor dictionary.' | |
| % field.name) | |
|
field_names = set([field.name for field in obj.DESCRIPTOR.fields]) |
|
| if strict: | |
|
for key in adict.keys(): |
|
|
if key not in field_names: |
|
| raise ConvertException( | |
|
'Key "%s" can not be mapped to field in %s class.' |
|
|
% (key, type(obj))) |
|
|
for field in obj.DESCRIPTOR.fields: |
|
|
if not field.name in adict: |
|
| continue | |
| msg_type = field.message_type | |
|
if field.label == FD.LABEL_REPEATED: |
|
|
if field.type == FD.TYPE_MESSAGE: |
|
|
for sub_dict in adict[field.name]: |
|
|
item = getattr(obj, field.name).add() |
|
| item.CopyFrom(dict2pb(msg_type._concrete_class, sub_dict)) | |
| else: | |
| map(getattr(obj, field.name).append, adict[field.name]) | |
| else: | |
|
if field.type == FD.TYPE_MESSAGE: |
|
| value = dict2pb(msg_type._concrete_class, adict[field.name]) | |
| getattr(obj, field.name).CopyFrom(value) | |
| else: | |
| setattr(obj, field.name, adict[field.name]) | |
| return obj | |
|
def pb2dict(obj): |
|
| """ | |
| Takes a ProtoBuf Message obj and convertes it to a dict. | |
| """ | |
| adict = {} | |
|
if not obj.IsInitialized(): |
|
|
return None |
|
|
for field in obj.DESCRIPTOR.fields: |
|
|
if not getattr(obj, field.name): |
|
| continue | |
|
if not field.label == FD.LABEL_REPEATED: |
|
|
if not field.type == FD.TYPE_MESSAGE: |
|
|
adict[field.name] = getattr(obj, field.name) |
|
| else: | |
| value = pb2dict(getattr(obj, field.name)) | |
| if value: | |
| adict[field.name] = value | |
| else: | |
|
if field.type == FD.TYPE_MESSAGE: |
|
| adict[field.name] = \ | |
|
[pb2dict(v) for v in getattr(obj, field.name)] |
|
| else: | |
|
adict[field.name] = [v for v in getattr(obj, field.name)] |
|
| return adict | |
|
def json2pb(cls, json, strict=False): |
|
| """ | |
| Takes a class representing the Protobuf Message and fills it with data from | |
| the json string. | |
| """ | |
| return dict2pb(cls, simplejson.loads(json), strict) | |
|
def pb2json(obj): |
|
| """ | |
| Takes a ProtoBuf Message obj and convertes it to a json string. | |
| """ | |
|
return simplejson.dumps(pb2dict(obj), sort_keys=True, indent=4) |
json2pb
在功能测试或集成测试中，用json造输入数据，然后moc测试脚本将json转化为protobuf发送给被测试模块或服务，是非常常见的功能测试手段。
如果测试脚本用Python来写的话，一般的做法是用的Python调用json模块中函数解析json文件，然后新建protobuf对象，依次填写各字段，然后发送出去。
当然如果愿意造上面的*也没关系，如果想偷懒也是可行的，pbjson.py脚本就为你干这事提供了温床
，下面会介绍这个过程：
1、造json文件，内容如下：
#vi testjson2pb.json
{
"name":"scq",
"age":30,
"work_unit":"taobao",
"class_mate":[
{
"name":"jim",
"age":30
}
]
}
2、造protobuf文件，内容如下：
#vi testjson2pb.proto
//class mate
package json2pb;
message PersonInfo {
//my name
required string name = 1;
//my age
optional int32 age = 2;
//my work unit
optional string work_unit = 3;
message ClassMate {
//name
optional string name = 1;
//age
optional uint32 age = 2;
}
repeated ClassMate class_mate = 4;
}
3、生成protobuf对应python文件：
#protoc -I=. --python_out=. testjson2pb.proto
testjson2pb_pb2.py
4、编写测试例子，具体如下：
#vi testjson2pb.py
-------------------------------------------------------------------------------------------------
#!/usr/bin/env python
# coding=utf-8
import sys
import logging
import os
import time
import string
import pbjson
import simplejson
import testjson2pb_pb2
def main():
f = file("testjson2pb.json")
s = simplejson.load(f)
f.close
t = pbjson.dict2pb(testjson2pb_pb2.PersonInfo, s)
print t
if __name__ == "__main__":
main()
如果测试脚本用Python来写的话，一般的做法是用的Python调用json模块中函数解析json文件，然后新建protobuf对象，依次填写各字段，然后发送出去。
当然如果愿意造上面的*也没关系，如果想偷懒也是可行的，pbjson.py脚本就为你干这事提供了温床
1、造json文件，内容如下：
#vi testjson2pb.json
{
"name":"scq",
"age":30,
"work_unit":"taobao",
"class_mate":[
{
"name":"jim",
"age":30
}
]
}
2、造protobuf文件，内容如下：
#vi testjson2pb.proto
//class mate
package json2pb;
message PersonInfo {
//my name
required string name = 1;
//my age
optional int32 age = 2;
//my work unit
optional string work_unit = 3;
message ClassMate {
//name
optional string name = 1;
//age
optional uint32 age = 2;
}
repeated ClassMate class_mate = 4;
}
3、生成protobuf对应python文件：
#protoc -I=. --python_out=. testjson2pb.proto
testjson2pb_pb2.py
4、编写测试例子，具体如下：
#vi testjson2pb.py
-------------------------------------------------------------------------------------------------
#!/usr/bin/env python
# coding=utf-8
import sys
import logging
import os
import time
import string
import pbjson
import simplejson
import testjson2pb_pb2
def main():
f = file("testjson2pb.json")
s = simplejson.load(f)
f.close
t = pbjson.dict2pb(testjson2pb_pb2.PersonInfo, s)
print t
if __name__ == "__main__":
main()
5、执行脚本，结果如下：
#python testjson2pb.py
是不是很简单啊，自从有了这个脚本，再用不用担心人肉从json生成protobuf的问题了。
原文链接:http://blog.chinaunix.net/uid-27714502-id-4067350.html