nats-protobuf
nats-protobuf is a protoc plugin that generates client, server, and json over
http implementations of the services defined in the .proto file
The library is functional, but given how new it is, expect breaking changes.
Installation
go get github.com/savaki/nats-protobuf/...
Usage
The simplest usage is to use nats-protobuf along side your protoc go:generate line.
//go:generate protoc --go_out=. service.proto
//go:generate protoc --nats_out=. service.proto
Example
For example, given this protoc file, service.proto:
syntax = "proto3";
package simple;
message In {
string input = 1;
}
message Out {
string output = 1;
}
service RPC {
rpc InOut (In) returns (Out);
}The following is a complete example that illustrates a round trip using client and server transports generated by the nats-rpc plugin.
package main
import (
"context"
"fmt"
"github.com/nats-io/nats"
)
//go:generate protoc --go_out=. service.proto
//go:generate protoc --nats_out=. service.proto
type Service struct {
}
func (s Service) InOut(ctx context.Context, in *In) (*Out, error) {
return &Out{Output: "Hello " + in.Input}, nil
}
func main() {
ctx := context.Background()
nc, _ := nats.Connect(nats.DefaultURL)
// Server
cancel, _ := SubscribeRPC(ctx, nc, "subject", "id", Service{})
defer cancel()
// Client
client := NewRPC(nc, "subject")
out, _ := client.InOut(ctx, &In{Input: "Joe"})
fmt.Println(out.Output)
}Additional examples can be found in the examples directory.
Middleware
Both Listen and New* accept an optional list of middleware
filters to apply. The filters need to implement:
func(fn func(ctx context.Context, subject string, m *Message) error) func(ctx context.Context, subject string, m *Message) errorFor example, if we want to print out the elapsed execution time, we could write a timer as follows:
func Timer(fn nats_protobuf.HandlerFunc) nats_protobuf.HandlerFunc {
return func(ctx context.Context, subject string, msg *nats_protobuf.Message) error {
started := time.Now()
defer func() {
fmt.Println("elapsed:", time.Now().Sub(started))
}()
return fn(ctx, msg)
}
}For a more detailed example of middleware in use see the middleware package in the examples directory.
React
Typescript
Django
Laravel
Facebook
Microsoft
Google
Alibaba
D3
Tencent