[protobuf] Map support in proto2
Hey, The language guide claims that proto2 supports maps: https://developers.google.com/protocol-buffers/docs/proto#maps However, the compiler version 2.6.1 does not seem to like this construct. Also according to the release notes, maps seem to have been introduced only in version 3. Is the documentation inconsistent, or am I missing something? Best, Martin -- You received this message because you are subscribed to the Google Groups Protocol Buffers group. To unsubscribe from this group and stop receiving emails from it, send an email to protobuf+unsubscr...@googlegroups.com. To post to this group, send email to protobuf@googlegroups.com. Visit this group at http://groups.google.com/group/protobuf. For more options, visit https://groups.google.com/d/optout.
[protobuf] Re: Protobuf Buffers v3.0.0-alpha-1
Does this version support object type in C# ?
ex:
[ProtoMember(1)]
public object A {get;set;}
thank.
Vào 11:51:01 UTC+7 Thứ Năm, ngày 11 tháng 12 năm 2014, Feng Xiao đã viết:
Hi all,
I just published protobuf v3.0.0-alpha-1 on our github site:
https://github.com/google/protobuf/releases/tag/v3.0.0-alpha-1
This is the first alpha release of protobuf v3.0.0. In protobuf v3.0.0, we
will add a new protobuf language version (aka proto3) and support a wider
range of programming languages (to name a few: ruby, php, node.js,
objective-c). This alpha version contains C++ and Java implementation with
partial proto3 support (see below for details). In future releases we will
add support for more programming languages and implement the full proto3
feature set. Besides proto3, this alpha version also includes two other new
features: map fields and arena allocation. They are implemented for both
proto3 and the old protobuf language version (aka proto2).
We are currently working on the documentation of these new features and
when it's ready it will be updated to our protobuf developer guide
https://developers.google.com/protocol-buffers/docs/overview. For the
time being if you have any questions regarding proto3 or other new
features, please post your question in the discussion group.
CHANGS
===
Version 3.0.0-alpha-1 (C++/Java):
General
* Introduced Protocol Buffers language version 3 (aka proto3).
When protobuf was initially opensourced it implemented Protocol Buffers
language version 2 (aka proto2), which is why the version number
started from v2.0.0. From v3.0.0, a new language version (proto3) is
introduced while the old version (proto2) will continue to be
supported.
The main intent of introducing proto3 is to clean up protobuf before
pushing the language as the foundation of Google's new API platform.
In proto3, the language is simplified, both for ease of use and to
make it available in a wider range of programming languages. At the
same time a few features are added to better support common idioms
found in APIs.
The following are the main new features in language version 3:
1. Removal of field presence logic for primitive value fields,
removal
of required fields, and removal of default values. This makes
proto3
significantly easier to implement with open struct
representations,
as in languages like Android Java, Objective C, or Go.
2. Removal of unknown fields.
3. Removal of extensions, which are instead replaced by a new
standard
type called Any.
4. Fix semantics for unknown enum values.
5. Addition of maps.
6. Addition of a small set of standard types for representation of
time,
dynamic data, etc.
7. A well-defined encoding in JSON as an alternative to binary proto
encoding.
This release (v3.0.0-alpha-1) includes partial proto3 support for C++
and
Java. Items 6 (well-known types) and 7 (JSON format) in the above
feature
list are not implemented.
A new notion syntax is introduced to specify whether a .proto file
uses proto2 or proto3:
// foo.proto
syntax = proto3;
message Bar {...}
If omitted, the protocol compiler will generate a warning and proto2
will
be used as the default. This warning will be turned into an error in a
future release.
We recommend that new Protocol Buffers users use proto3. However, we
do not
generally recommend that existing users migrate from proto2 from
proto3 due
to API incompatibility, and we will continue to support proto2 for a
long
time.
* Added support for map fields (implemented in C++/Java for both proto2
and
proto3).
Map fields can be declared using the following syntax:
message Foo {
mapstring, string values = 1;
}
Data of a map field will be stored in memory as an unordered map and it
can be accessed through generated accessors.
C++
* Added arena allocation support (for both proto2 and proto3).
Profiling shows memory allocation and deallocation constitutes a
significant
fraction of CPU-time spent in protobuf code and arena allocation is a
technique introduced to reduce this cost. With arena allocation, new
objects will be allocated from a large piece of preallocated memory and
deallocation of these objects is almost free. Early adoption shows 20%
to
50% improvement in some Google binaries.
To enable arena support, add the following option to your .proto file:
option cc_enable_arenas = true;
Protocol compiler will generate additional code to make the generated
message classes work with arenas. This does not change the existing API
of protobuf messages and does not affect wire format. Your existing
code
should continue to
[protobuf] Re: map issue in protoc 2.6.1 on Windows
I agree, the documentation is completely misleading. I just spent an hour
updating to version 2.6.1, assuming maps didn't work because I had version
2.6.0.
I suppose I should have checked here first. It would be nice if the docs
where up to date.
On Monday, July 6, 2015 at 1:39:37 PM UTC-5, adam@btinternet.com wrote:
According to the Language Guide an associative map can be used in data
definition https://developers.google.com/protocol-buffers/docs/proto#maps
When I try using it on Windows 7 I am getting a compiler error on the left
angle bracket in required mapuint32, bytes properties = 1;
entity.proto file content:
message EntityBuffer {
required mapuint32, bytes properties = 1;
}
Command:
protoc --java_out=. entity.proto
Error
entity.proto:2:13: Expected field name.
protoc --version returns
libprotoc 2.6.1
I am a bit puzzled.
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[protobuf] Dealing with unsupported APIs in dependency chain
Hi everyone, I am trying to add to my dependency list a proto that does not support go api. Everything above my library in the dependency chain supports go api and everything below the dependency I am trying to include does not. My understanding is that I have two options: 1. Change everything below me to support go api. 2. Make a replica of what I need from the dependency I am trying to add. Both of these seem sub optimal to me. Is there a any other option I could look into. Thanks! -- You received this message because you are subscribed to the Google Groups Protocol Buffers group. To unsubscribe from this group and stop receiving emails from it, send an email to protobuf+unsubscr...@googlegroups.com. To post to this group, send email to protobuf@googlegroups.com. Visit this group at http://groups.google.com/group/protobuf. For more options, visit https://groups.google.com/d/optout.
[protobuf] Issue with Python Protobuf library + Anaconda + cpp_implementation optimization
I've been unable to get the Python protobuf library on Mac OS X working with Anaconda with Protobuf's cpp_implementation (which uses a C++ backend for Python's protobuf library to speed things up). Have others been able to successfully get this to work? I've opened an issue to track this: https://github.com/google/protobuf/issues/647 Best, Brad Neuberg -- You received this message because you are subscribed to the Google Groups Protocol Buffers group. To unsubscribe from this group and stop receiving emails from it, send an email to protobuf+unsubscr...@googlegroups.com. To post to this group, send email to protobuf@googlegroups.com. Visit this group at http://groups.google.com/group/protobuf. For more options, visit https://groups.google.com/d/optout.
[protobuf] [ANN] protobuf implementation in cython, designed with performance and simplicity in mind.
https://github.com/yihuang/cprotobuf cprotobuf is a protobuf implementation in cython, which has good performance and simple api, it generates readable code. -- You received this message because you are subscribed to the Google Groups Protocol Buffers group. To unsubscribe from this group and stop receiving emails from it, send an email to protobuf+unsubscr...@googlegroups.com. To post to this group, send email to protobuf@googlegroups.com. Visit this group at http://groups.google.com/group/protobuf. For more options, visit https://groups.google.com/d/optout.
Re: [protobuf] Map support in proto2
On Wed, Jul 29, 2015 at 1:50 AM, goo...@m3fintech.com wrote: Hey, The language guide claims that proto2 supports maps: https://developers.google.com/protocol-buffers/docs/proto#maps However, the compiler version 2.6.1 does not seem to like this construct. Also according to the release notes, maps seem to have been introduced only in version 3. Is the documentation inconsistent, or am I missing something? I think we can improve the document by explicitly pointing out that map fields are only supported from version 3.0.0. I know it's quite confusing but proto2 syntax does not correspond to version 2.x.x. Proto2 is also supported in version 3.0.0. If you want the latest features/bug-fixes of proto2 syntax, you should use version 3.0.0 rather than 2.6.1. Best, Martin -- You received this message because you are subscribed to the Google Groups Protocol Buffers group. To unsubscribe from this group and stop receiving emails from it, send an email to protobuf+unsubscr...@googlegroups.com. To post to this group, send email to protobuf@googlegroups.com. Visit this group at http://groups.google.com/group/protobuf. For more options, visit https://groups.google.com/d/optout. -- You received this message because you are subscribed to the Google Groups Protocol Buffers group. To unsubscribe from this group and stop receiving emails from it, send an email to protobuf+unsubscr...@googlegroups.com. To post to this group, send email to protobuf@googlegroups.com. Visit this group at http://groups.google.com/group/protobuf. For more options, visit https://groups.google.com/d/optout.
