Uptime Checker Actor

Introduction

This repo acts as a FVM registry for node uptime checking. At a basic level, many use cases require a way of knowing which nodes are active/live in a p2p network. The purpose is to have a set of, what we call, checkers constantly ping those nodes to see which ones are still active and which ones are down.

At the same time, the checkers will crosscheck each other to ensure checkers are also online. If any checker is found to be done, voting would be carried out among checkers. If a quorum of the voters has reported a checker to be down, then that checker will be removed from the registry

This project contains two parts:

• FVM actor (this repo)
• Go Checker

This FVM actor is the registry running in a FVM. It provides the CRUD functions for nodes and checkers registration lifecycle. The Go Checker is the checker implementation in golang that ping the nodes/checkers, provide node uptime informations, see more details in the repo linked above.

Build

To compile:

cargo build

You should be able to see the uptime_checker.compact.wasm compiled generated.

Set up a local fvm according to this tutorial.

Deploy the actor:

./lotus chain install-actor uptime_checker.compact.wasm

Once the transaction is processed, obtain the message cid.

Create the actor with

./lotus chain create-actor ${MESSAGE_CID} ewogICAgImlkcyI6IFtdLAogICAgImNyZWF0b3JzIjogW10sCiAgICAiYWRkcmVzc2VzIjogW10KfQ==

In the above command, ewogICAgImlkcyI6IFtdLAogICAgImNyZWF0b3JzIjogW10sCiAgICAiYWRkcmVzc2VzIjogW10KfQ is the base64 encoded json string. You can replace with other configurations.

Once you obtain the address, you can interact with the actor. Use the following template to operate:

./lotus chain invoke <METHOD_NUMBER> <PAYLOAD>

Refer to UptimeCheckerActor trait in src/traits.rs for more reference.