protomap

Protomap is a map[string]any <-> protobuf binary encoder/decoder based on protoreflect.

Like json Unmarshal/Marshal to/from generic map, but for protobuf.

Why?

To operate protobuf-encoded messages without updating generated code each time when your service need to work with tons of updated/new .proto.

How?

Mapper creates new message from descriptor every Encode/Decode call, so, it should be concurrent-safe to encode/decode multiple messages at the same time using one Mapper.

Create Mapper

protofiles := []string{/* list of .proto files, which contains messages encode/decode to */}

/* https://pkg.go.dev/github.com/bufbuild/protocompile#Compiler that will be used to compile .proto files; may be nil */
compiler := protocompile.Compiler{
    Resolver: protocompile.WithStandardImports(&protocompile.SourceResolver{}),
}

mapper, err := protomap.NewMapper(compiler, protofiles...)
if err != nil {
    panic(err)
}

Decode your message from bytes slice to map

/* full name of the message to decode */
messageName := "protomap.test.WithTimeDuration" 
result, err := mapper.Decode(binaryData, messageName)
if err != nil {
    panic(err)
}

Encode your map to bytes slice

/* full name of the message to encode */
messageName := "protomap.test.WithTimeDuration"
binaryData, err := mapper.Encode(gomap, messageName)
if err != nil {
    panic(err)
}

Interceptors

Interceptors is a functions that allows you to encode/decode custom messages to Go types, for example, time.Time <-> google.protobuf.Timestamp.

You need to pass interceptor(s) to Encode/Decode mapper methods to apply it:

messageName := "protomap.test.WithTimeDuration"
binaryData, err := mapper.Encode(gomap, messageName, interceptors.DurationEncoder, interceptors.TimeEncoder)
if err != nil {
    panic(err)
}

A few ready functions you can find in interceptors dir.