Re: [protobuf] Re: Dynamically determine the type of a message
On Feb 11, 2010, at 15:44 , alexrichard...@gmail.com wrote: Are there known issues which arise from a union type with a large number of extensions? The problem that concerns me is that I need to have unique extension ids. This seems difficult when using Protocol Buffers as an RPC system, unless I'm thinking about this in the wrong way? I haven't actually thought about this very hard. Evan -- Evan Jones http://evanjones.ca/ -- You received this message because you are subscribed to the Google Groups "Protocol Buffers" group. To post to this group, send email to proto...@googlegroups.com. To unsubscribe from this group, send email to protobuf+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/protobuf?hl=en.
Re: Re: [protobuf] Re: Dynamically determine the type of a message
... I think union types are the best choice for a "small" number of possible messages. However, if you really need to support *any* type of message, you could consider adding a "header" message of a known type that includes the fully-qualified message name as returned by message->GetDescriptor()->full_name(), or some other unique "message type" indicator. Good luck, Evan -- Evan Jones Union types in combination with 'extensions' seems like the right solution for this problem in almost all cases, whether the number of message types is large or small. Using a separate header message adds lots of complications as you then need to write additional code to instantiate the 'payload' message type etc... I was using a header message a while back, and migrated to union types with great success. Granted, I do still have a fairly small number of message types, but I am not aware of any issues which would arise from scaling to a very large set of messages. Are there known issues which arise from a union type with a large number of extensions? Alex -- You received this message because you are subscribed to the Google Groups "Protocol Buffers" group. To post to this group, send email to proto...@googlegroups.com. To unsubscribe from this group, send email to protobuf+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/protobuf?hl=en.
Re: [protobuf] how to get RepeatedField object
No, there isn't a way to get the RepeatedField from the reflection interface. You can only do so via the generated interface. On Thu, Feb 11, 2010 at 5:57 AM, Romain Francois < romain.francois.r.enthusi...@gmail.com> wrote: > Hello, > > How can I get hold of a RepeatedField object to manage a repeated field in > C++. > > In RProtoBuf, we do a lot of : > > for( int i=0; i INTEGER(res)[i] = (int) ref->GetRepeatedInt32( *message, fieldDesc, i ) ; > } > > where essentially the INTEGER macro gives a pointer to the beginning of the > int array we are filling. > > I'd like to replace this using e.g std::copy > > RepeatedField field ; > std::copy( field.begin(), field.end(), INTEGER(res) ) ; > > but I can't find how to actually get hold of a RepeatedField object. > > Is it possible ? > > Romain > > -- > Romain Francois > Professional R Enthusiast > +33(0) 6 28 91 30 30 > http://romainfrancois.blog.free.fr > |- http://tr.im/NrTG : Rcpp 0.7.5 > |- http://tr.im/MPYc : RProtoBuf: protocol buffers for R > `- http://tr.im/KfKn : Rcpp 0.7.2 > > -- > You received this message because you are subscribed to the Google Groups > "Protocol Buffers" group. > To post to this group, send email to proto...@googlegroups.com. > To unsubscribe from this group, send email to > protobuf+unsubscr...@googlegroups.com > . > For more options, visit this group at > http://groups.google.com/group/protobuf?hl=en. > > -- You received this message because you are subscribed to the Google Groups "Protocol Buffers" group. To post to this group, send email to proto...@googlegroups.com. To unsubscribe from this group, send email to protobuf+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/protobuf?hl=en.
[protobuf] how to get RepeatedField object
Hello, How can I get hold of a RepeatedField object to manage a repeated field in C++. In RProtoBuf, we do a lot of : for( int i=0; iGetRepeatedInt32( *message, fieldDesc, i ) ; } where essentially the INTEGER macro gives a pointer to the beginning of the int array we are filling. I'd like to replace this using e.g std::copy RepeatedField field ; std::copy( field.begin(), field.end(), INTEGER(res) ) ; but I can't find how to actually get hold of a RepeatedField object. Is it possible ? Romain -- Romain Francois Professional R Enthusiast +33(0) 6 28 91 30 30 http://romainfrancois.blog.free.fr |- http://tr.im/NrTG : Rcpp 0.7.5 |- http://tr.im/MPYc : RProtoBuf: protocol buffers for R `- http://tr.im/KfKn : Rcpp 0.7.2 -- You received this message because you are subscribed to the Google Groups "Protocol Buffers" group. To post to this group, send email to proto...@googlegroups.com. To unsubscribe from this group, send email to protobuf+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/protobuf?hl=en.
Re: [protobuf] Re: Dynamically determine the type of a message
fokenrute wrote: Ok, so, I will likely opt for Enum Types. Thanks for answering. I think union types are the best choice for a "small" number of possible messages. However, if you really need to support *any* type of message, you could consider adding a "header" message of a known type that includes the fully-qualified message name as returned by message->GetDescriptor()->full_name(), or some other unique "message type" indicator. Good luck, Evan -- Evan Jones http://evanjones.ca/ -- You received this message because you are subscribed to the Google Groups "Protocol Buffers" group. To post to this group, send email to proto...@googlegroups.com. To unsubscribe from this group, send email to protobuf+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/protobuf?hl=en.
[protobuf] Re: Dynamically determine the type of a message
Every message has a descriptor object associated. Look in the c++ API reference (http://code.google.com/apis/protocolbuffers/docs/reference/ cpp/index.html) for it. Once you get the descriptor, you can get a string type by calling name(). On Feb 10, 5:02 pm, fokenrute wrote: > Hi, I'm developing a C++ application and I use Protocol Buffers for > network communications. > Somewhere in my app, I receive messages which can be of different > types and I'm searching for a mean to dynamically determine the type > of these messages (which are stored in a buffer). I read something > about the reflexion interface, but I don't konw how to use it to do > what i want. > Thanks in advance for your replies. -- You received this message because you are subscribed to the Google Groups "Protocol Buffers" group. To post to this group, send email to proto...@googlegroups.com. To unsubscribe from this group, send email to protobuf+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/protobuf?hl=en.
