protoc-gen-json

May 13, 2015 ยท View on GitHub

cmd/protoc-gen-json contains a protoc compiler plugin for generating JSON dumps of protoc plugin generation requests, i.e. the literal request to the protoc-gen-json command from protoc.

As it is literally the JSON form of plugin.CodeGeneratorRequest, it can be unmarshaled into the same exact structure which is useful for writing tests without invoking protoc directly (and attemping to detect plugin failure through the compiler proxy).

Installation

First install Go and Protobuf itself, then install the plugin using go get:

go get -u sourcegraph.com/sourcegraph/prototools/cmd/protoc-gen-json

Usage

Simply invoke protoc with the --json_out command-line parameter:

protoc --json_out="<OUT_DIR>" input.proto
protoc --json_out="<OPTIONS>:<OUT_DIR>" input.proto

Where <OPTIONS> is a comma-seperated list of key=value,key2=value2 options (which are listed in detail below). For example:

protoc --json_out="dump/" a.proto b.proto

Would produce a JSON dump file (out.json) for both a.proto and b.proto inside the dump/ directory.

Options

OptionDefaultDescription
outout.jsonOutput file name (not directory).
indent (two spaces)Indention string to use for each nested JSON element.

Issues

If you run into trouble or have questions, please open an issue.