Golang ProtoBuf Faker Compiler

A protoc plugin that generates New<MessageName>GomeetFaker() *<MessageName> functions.

Paint me a code picture

Let's take the following proto3 snippet:

syntax = "proto3";

package gomeetfaker.examples;

option go_package = "pb";

import "github.com/gomeet/go-proto-gomeetfaker/gomeetfaker.proto";

message Book {
  string uuid   = 1 [(gomeetfaker.field).uuid.version = "V4"];
  string author = 2 [(gomeetfaker.field).name.name = true];
  string title  = 3 [(gomeetfaker.field).lorem.string = true];
  string isbn10 = 4 [(gomeetfaker.field).code.isbn10 = true];
  string isbn13 = 5 [(gomeetfaker.field).code.isbn13 = true];
}

The generated code is understandable. Take a look:

func NewBookGomeetFaker() *Book {
	this := &Book{}
	this.Uuid = uuid.New().String()
	this.Author = faker.Name().Name()
	this.Title = faker.Lorem().String()
	this.Isbn10 = faker.Code().Isbn10()
	this.Isbn13 = faker.Code().Isbn13()
	return this
}

For an exhaustive list of faker rules see examples/full/pb/pb.proto

Installing and using

The protoc compiler expects to find plugins named proto-gen-XYZ on the execution $PATH. So first:

export PATH=${PATH}:${GOPATH}/bin

Then, do the usual

go get github.com/gomeet/go-proto-gomeetfaker/protoc-gen-gomeetfaker

Your protoc builds probably look very simple like:

protoc  \
	--proto_path=. \
	--go_out=. \
	*.proto

That's fine, until you encounter .proto includes. Because go-proto-gomeetfaker uses annotations inside the .proto files themselves, it's .proto definition (and the Google descriptor.proto itself) need to on the protoc include path. Hence the above becomes:

protoc  \
	--proto_path=${GOPATH}/src \
	--proto_path=${GOPATH}/src/github.com/google/protobuf/src \
	--proto_path=. \
	--go_out=. \
	--gomeetfaker_out=. \
	*.proto

Or with gogo protobufs:

protoc  \
	--proto_path=${GOPATH}/src \
	--proto_path=${GOPATH}/src/github.com/gogo/protobuf/protobuf \
	--proto_path=. \
	--gogo_out=. \
	--gomeetfaker_out=gogoimport=true:. \
	*.proto

Basically the magical incantation (apart from includes) is the --gomeetfaker_out. That triggers the protoc-gen-gomeetfaker plugin to generate mymessage.gomeetfaker.pb.go. That's it :)

Make directives

• make - Installing all development tools and making specific platform binary (in _build directory). It's equivalent to make build.
• make build - Installing all development tools and making specific platform binary (in _build directory).
• make clean - Removing all generated files (all tools, all compiled files, generated from proto). It's equivalent to make tools-clean package-clean proto-clean.
• make proto - Generating files from proto (gomeetfaker.proto only).
• make proto-examples - Generating files from proto (gomeetfaker.proto only).
• make proto-clean - Clean up generated files from the proto file.
• make tools - Installing all development tools.
• make tools-sync - Re-Syncronizes development tools.
• make tools-sync-retool - Re-Syncronizes development tools (retool only).
• make tools-sync-protoc - Re-Syncronizes development tools (protoc only).
• make tools-upgrade - Upgrading all development tools.
• make tools-clean - Uninstall all development tools.
• make dep - Executes the dep ensure command.

License

go-proto-gomeetfaker is released under the Apache 2.0 license. See the LICENSE file for details.

TODO

• proto2 support
• tests
• more examples
• remove github.com/dmgk/faker depency. (Now it's github.com/gomeet/faker)