I’m not familiar with Google Protocol Buffers, but my interpretation of the documentation is: use uint32 if the value cannot be negative use sint32 if the value is pretty much as likely to be negative as not (for some fuzzy definition of “as likely to be”) use int32 if the value could be negative, but … Read more
Yes, the best approach is to make the first value in the enum something like UNKNOWN = 0. Then old programs reading a protobuf with an enum value they don’t recognize will see it as UNKNOWN and hopefully they can handle that reasonably, eg by skipping that element. If you want to do this you’ll … Read more
10MB is pushing it but you’ll probably be OK. Protobuf has a hard limit of 2GB, because many implementations use 32-bit signed arithmetic. For security reasons, many implementations (especially the Google-provided ones) impose a size limit of 64MB by default, although you can increase this limit manually if you need to. The implementation will not … Read more
I had the same need, and got the same error. I do not believe this is possible. Here is the relevant BNF definitions from the language specification. https://developers.google.com/protocol-buffers/docs/reference/proto3-spec messageType = [ “.” ] { ident “.” } messageName mapField = “map” “<” keyType “,” type “>” mapName “=” fieldNumber [ “[“fieldOptions “]” ] “;” type … Read more
For pure proto generations you can do the following protoc –go_out=paths=source_relative:./gen -I. authenticator.proto or to generate for grpc the following can be used protoc –go_out=plugins=grpc:./gen –go_opt=paths=source_relative authenticator.proto If that fails you likely have a newer version of protoc and need to use the following command instead. protoc –go-grpc_out=./gen –go-grpc_opt=paths=source_relative authenticator.proto This is just Google making … Read more
Turns out there is a way to find out if a default value is actually missing or not (thanks to some friends at google for this answer): message Record { uint32 fileno = 1; uint64 pos = 2; uint64 bmsPos = 3; oneof scanMode_present { uint32 scanMode = 4; } uint32 version = 5; // … Read more
The command line you are showing does not enable the grpc plugin. You need to specify an _out argument for the grpc plugin, which enables the plugin and specifies where it should output files. Since the plugin is likely not in your PATH, you also need to tell protoc how to find the plugin with … Read more
EDIT: The freeze_graph.py script, which is part of the TensorFlow repository, now serves as a tool that generates a protocol buffer representing a “frozen” trained model, from an existing TensorFlow GraphDef and a saved checkpoint. It uses the same steps as described below, but it much easier to use. Currently the process isn’t very well … Read more
Google designed protobuf to be pretty forgiving with versioning: unexpected data is either stored as “extensions” (making it round-trip safe), or silently dropped, depending on the implementation new fields are generally added as “optional”, meaning that old data can be loaded successfully however: do not renumber fields – that would break existing data you should … Read more
There’s a few reasons, mostly to do with where these are used – see struct.proto. StringValue can be null, string often can’t be in a language interfacing with protobufs. e.g. in Go strings are always set; the “zero value” for a string is “”, the empty string, so it’s impossible to distinguish between “this value … Read more