hermez-node

Go implementation of the Hermez node.

Developing

Go version

The hermez-node has been tested with go version 1.14

Unit testing

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

POSTGRES_PASS=yourpasswordhere sudo docker run --rm --name hermez-db-test -p 5432:5432 -e POSTGRES_DB=hermez -e POSTGRES_USER=hermez -e POSTGRES_PASSWORD="$POSTGRES_PASS" -d postgres

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

POSTGRES_PASS=yourpasswordhere go test -p 1 ./...

NOTE: -p 1 forces execution of package test in serial. Otherwise they may be executed in paralel and the test may find unexpected entries in the SQL databse 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. This will be removed once the API can be properly initialized, with data from the synchronizer and so on. To use this, run:

FAKE_SERVER=yes POSTGRES_PASS=yourpasswordhere go test -timeout 0  ./api -p 1 -count 1 -v`

Lint

All Pull Requests need to pass the configured linter.

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

golangci-lint run --timeout=5m -E whitespace -E gosec -E gci -E misspell -E gomnd -E gofmt -E goimports -E golint --exclude-use-default=false --max-same-issues 0

Usage

Node

See cli/node/README.md

Proof Server

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

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)

/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 unecessary reads an 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