The numbered tags are used to match fields when serializing and deserializing the data. Obviously, if you change the numbering scheme, and apply this change to both serializer and deserializer, there is no issue. Consider though, if you saved data with the first numbering scheme, and loaded it with the second one, it would try … Read more
Changing a field name will not affect the protobuf encoding or compatibility between applications that use proto definitions which differ only by field names. The binary protobuf encoding is based on tag numbers, so that is what you need to preserve. You can even change a field type to some extent (check the type table … Read more
https://developers.google.com/protocol-buffers/docs/proto3#scalar bytes: May contain any arbitrary sequence of bytes no longer than 232.
In proto3 the extend keyword has been replaced. From the docs: If you are already familiar with proto2 syntax, the Any type replaces extensions. syntax = “proto3”; import “google/protobuf/any.proto”; message Foo { google.protobuf.Any bar = 1; } But beware: Any is essentially a bytes blob. Most of the times it is better to use Oneof: … Read more
You should probably use string or bytes to represent a UUID. Use string if it is most convenient to keep the UUID in human-readable format (e.g. “de305d54-75b4-431b-adb2-eb6b9e546014”) or use bytes if you are storing the 128-bit value raw. (If you aren’t sure, you probably want string.) Wrapping the value in a message type called UUID … Read more
My understanding is that proto3 no longer allows you to detect field presence and no longer supports non-zero default values because this makes it easier to implement protobufs in terms of “plain old structs” in various languages, without the need to generate accessor methods. This is perceived as making Protobuf easier to use in those … Read more
sudo ldconfig or export LD_LIBRARY_PATH=/usr/local/lib should solve the problem.
Option 1 – Use stream: rpc GetItems (ItemsQuery) returns (stream Item) { } Option 2 – Set a response message which will use a repeated object: service MyService { rpc GetItem (ItemQuery) returns (ItemResponse) { } } message ItemQuery { int id = 1; } message ItemResponse { repeated Item items = 1; } message … Read more
You have to specify an input type. If you don’t want the method to take any parameters, define an empty message type, like: message WhoAreYouParams {} The reason this is required is so that if you later need to add an optional parameter, you can do so without breaking existing code.
There is Timestamp message type since protobuf 3.0, that’s how to create it in model: syntax = “proto3”; import “google/protobuf/timestamp.proto”; message MyMessage { google.protobuf.Timestamp my_field = 1; } timestamp.proto file contains examples of Timestamp using, including related to Linux and Windows programs. Example 1: Compute Timestamp from POSIX time(). Timestamp timestamp; timestamp.set_seconds(time(NULL)); timestamp.set_nanos(0); Example 2: … Read more