MDOJ judger

From high level, the judger is a grpc server that provide JudgeService, which is defined in /proto/judge.proto.

The interface should provide ability to

• Judge a submission(compile, run, compare output)
• Stream the output of a submission(compile, run, stream) Like leetcode, we should provide experience of watching the output of a submission in real time with setting up development environment.
• Get List of available languages
• Get system utilization

Design

Developing a GRPC server works in a similar way to developing a function, but remote and stateful.

To implement high level function, we need to implement the following functions:

• filesystem module: mount a filesystem in userspace
• sandbox module: run a program in a sandbox with resource/permission limitation applied
• language module: compile/run a program for a specific programing language

See dev.md in each module for more details.