hermez-node

Go implementation of the Hermez node.

Developing

Go version

The hermez-node has been tested with go version 1.14

Build

Build the binary and check the current version:

$ make build
$ bin/node version

Run

First you must edit the default/template config file into cli/node/cfg.buidler.toml, there are more information about the config file into cli/node/README.md

After setting the config, you can build and run the Hermez Node as a synchronizer:

$ make run

Or build and run as a coordinator, and also passing the config file from other location:

$ MODE=sync CONFIG=cli/node/cfg.buidler.toml make run

To check the useful make commands:

$ make help

Unit testing

Running the unit tests requires a connection to a PostgreSQL database. You can run PostgreSQL with docker easily this way (where yourpasswordhere should be your password):

$ POSTGRES_PASS="yourpasswordhere" make run-database-container

Afterward, run the tests with the password as env var:

$ POSTGRES_PASS="yourpasswordhere" make test

NOTE: -p 1 forces execution of package test in serial. Otherwise, they may be executed in parallel, and the test may find unexpected entries in the SQL database because it's shared among all tests.

There is an extra temporary option that allows you to run the API server using the Go tests. It will be removed once the API can be properly initialized with data from the synchronizer. To use this, run:

$ POSTGRES_PASS="yourpasswordhere" make test-api-server

Lint

All Pull Requests need to pass the configured linter.

To run the linter locally, first, install golangci-lint.
Afterward, you can check the lints with this command:

$ make gocilint

Usage

Node

See cli/node/README.md

Proof Server

The node in mode coordinator requires a proof server (a server capable of calculating proofs from the zkInputs). There is a mock proof server CLI at test/proofserver/cli for testing purposes.

Usage of test/proofserver/cli:

USAGE:
    go run ./test/proofserver/cli OPTIONS

OPTIONS:
  -a string
        listen address (default "localhost:3000")
  -d duration
        proving time duration (default 2s)

Also, the Makefile commands can be used to run and stop the proof server in the background:

$ make run-proof-mock
$ make stop-proof-mock

/tmp as tmpfs

For every processed batch, the node builds a temporary exit tree in a key-value DB stored in /tmp. It is highly recommended that /tmp is mounted as a RAM file system in production to avoid unnecessary reads a writes to disk. This can be done by mounting /tmp as tmpfs; for example, by having this line in /etc/fstab:

tmpfs			/tmp		tmpfs		defaults,noatime,mode=1777	0 0