dgoffredo / dogpack

check MessagePack against a protobuf schema

DogPack

It's a Protocol Buffer schema based validator for MessagePack. For dogs.

Dependencies

dependencies/ contains git submodules that are the runtime dependencies of this tool. Run the following command to make sure they're cloned:

$ git submodule update --init --recursive

dependencies/protojson depends on the Protocol Buffer compiler, protoc. This you install as a system-level command line tool, e.g.

sudo apt install protobuf-compiler

The requirement is that protoc be available in the PATH.

protojson also depends on Python 3.

dependencies/massagepack depends on the NPM module "msgpack-lite". Once you've installed npm, you can install msgpack-lite via:

npm install msgpack-lite

Usage

This project is a Node.js library used to implement two command line tools:

• ./validate-msgpack [--message <type>] <proto> ...

  • Parses a specified Protocol Buffer schema files (.proto files), and then reads MessagePack formatted data from standard input.
  • If the input matches the schema, then the tool exits with status zero without producing any output.
  • If the input does not match the schema, then the tool prints a diagnostic to standard error and exits with a nonzero status.
  • Optionally specify the name of a Protocol Buffer message <type> against which the input will be validated. If <type> is not specified, then the topologically "highest" message type will be used, i.e. the message type having the largest number of message type descendants.

• ./validate-dogpack [--message <type>] <proto> ...

  • Behaves like validate-msgpack, except that the input MessagePack is expected to be in the "compact" format, where strings are replaced by integer offsets into a string table, and messages are represented as keyless arrays instead of as maps. The shape of such messages, as expressed in tisch, will be:
    • [[String, String, ...etc], [field_1_schema, field_2_schema, Any, ...etc]]
    • where the array of strings is the string table, and the array of schemas are the schemas for the fields of the message (in this example, the message has two fields).