Integration Testing Spec

[bigs]

Opening a new issue to start a discussion around integration testing for go-libp2p.

In order to test more complex behaviors of libp2p, it's clear we'll want some sort of test harness in place. In my view, there are two tiers of this that could use doing:

• Micro: Mocked out interfaces all throughout libp2p such that we can create intra-process virtual topologies. In such a scheme, we'd want to describe connectivity in some sort of DSL (e.g. host A can connect to host B, not host C) and then initiate tests in which a test runner spawns the relevant hosts and attempts to complete some scenario (e.g. host A communicates with host C via relay after X round trips). Useful for debugging protocols, etc.
• Macro: Cluster simulation infrastructure. Should be able to simulate very large clusters and record various telemetry. As much a benchmarking tool as a debugging tool! Useful for spotting performance regressions as well as emulating various attacks, etc.

I've got to run for now, but wanted to get this discussion started! I think both the micro and macro options are useful, so it's really just a matter of determining when we want to spec/implement.

@whyrusleeping @jbenet @mgoelzer

[Stebalien]

FYI, this is a good place to start for micro tests: https://github.com/libp2p/go-libp2p/tree/master/p2p/net/mock (although we should still have some form of DSL).

[bigs]

@Stebalien Awesome, thanks. I did eventually wade my way into that folder. Maybe even just a configuration interpreter that creates networks based on that interface.

[Stebalien]

Really, we could define those configurations using go datastructures instead of parsing a separate file. One can, e.g., write:

net := Make(TestNet{
  Nodes: []TestNode{
    {
      Name: "PeerA",
      ...
    },
  },
  Links: []Link{
    {
      From: "PeerA",
      To: "PeerB",
      DefaultUp: true,
      Latency: ...,
      ...
    }
  },
})

net.Link("PeerA").Down()

...

[bigs]

Yep! That sounds perfect

[bigs]

New home at protocol/research-grants#4