protoc-gen-jsonshim

protoc-gen-jsonshim is a plugin for protoc which generates MarshalJSON() and UnmarshalJSON() functions for .pb.go types. The implementations simply redirect to MarshalJSONPB() and UnmarshalJSONPB() respectively. This allows the types to be used with native Go JSON serialization.

Usage

Add the executable to your system's PATH, for example:

$ go install istio.io/tools/cmd/protoc-gen-jsonshim

Add the jsonshim_out option to your protoc command line, for example:

$ protoc --jsonshim_out=:output/path ...

Quirks

The generator is built off protoc-gen-gogo, which adds some imports that are not used, along with copying over file comments from the source file. See below for an example of the genrated code.

Examples Of Generated Code

// Code generated by protoc-gen-gogo. DO NOT EDIT.
// source: networking/v1alpha3/gateway.proto

package v1alpha3 // import "istio.io/api/networking/v1alpha3"

import (
    bytes "bytes"
    fmt "fmt"
    github_com_gogo_protobuf_jsonpb "github.com/gogo/protobuf/jsonpb"
    proto "github.com/gogo/protobuf/proto"
    _ "google.golang.org/genproto/googleapis/api/annotations"
    math "math"
)

// Reference imports to suppress errors if they are not otherwise used.
var _ = proto.Marshal
var _ = fmt.Errorf
var _ = math.Inf

// MarshalJSON is a custom marshaler for Gateway
func (this *Gateway) MarshalJSON() ([]byte, error) {
    str, err := GatewayMarshaler.MarshalToString(this)
    return []byte(str), err
}

// UnmarshalJSON is a custom unmarshaler for Gateway
func (this *Gateway) UnmarshalJSON(b []byte) error {
    return GatewayUnmarshaler.Unmarshal(bytes.NewReader(b), this)
}

// MarshalJSON is a custom marshaler for Gateway_SelectorEntry
func (this *Gateway_SelectorEntry) MarshalJSON() ([]byte, error) {
    str, err := GatewayMarshaler.MarshalToString(this)
    return []byte(str), err
}

// UnmarshalJSON is a custom unmarshaler for Gateway_SelectorEntry
func (this *Gateway_SelectorEntry) UnmarshalJSON(b []byte) error {
    return GatewayUnmarshaler.Unmarshal(bytes.NewReader(b), this)
}

// MarshalJSON is a custom marshaler for Server
func (this *Server) MarshalJSON() ([]byte, error) {
    str, err := GatewayMarshaler.MarshalToString(this)
    return []byte(str), err
}

// UnmarshalJSON is a custom unmarshaler for Server
func (this *Server) UnmarshalJSON(b []byte) error {
    return GatewayUnmarshaler.Unmarshal(bytes.NewReader(b), this)
}

// MarshalJSON is a custom marshaler for Server_TLSOptions
func (this *Server_TLSOptions) MarshalJSON() ([]byte, error) {
    str, err := GatewayMarshaler.MarshalToString(this)
    return []byte(str), err
}

// UnmarshalJSON is a custom unmarshaler for Server_TLSOptions
func (this *Server_TLSOptions) UnmarshalJSON(b []byte) error {
    return GatewayUnmarshaler.Unmarshal(bytes.NewReader(b), this)
}

// MarshalJSON is a custom marshaler for Port
func (this *Port) MarshalJSON() ([]byte, error) {
    str, err := GatewayMarshaler.MarshalToString(this)
    return []byte(str), err
}

// UnmarshalJSON is a custom unmarshaler for Port
func (this *Port) UnmarshalJSON(b []byte) error {
    return GatewayUnmarshaler.Unmarshal(bytes.NewReader(b), this)
}

var (
    GatewayMarshaler   = &github_com_gogo_protobuf_jsonpb.Marshaler{}
    GatewayUnmarshaler = &github_com_gogo_protobuf_jsonpb.Unmarshaler{}
)