zksync-forwarder

Install

Install Node (requires version 14 or higher, run node --version). We suggest you to install nvm.

npm install express
npm install json-rpc-2.0
npm install node-fetch
npm install ethers
npm install zksync
npm install async-mutex
npm install json-bigint

Default JSON parser cannot handle big integers, what is required in our case. We need to replace default parser with JSONbig and we have to replace it manually in the libraries. Run

sed -i "1s/^/var JSONbig = require('json-bigint'); \n/" node_modules/express/lib/response.js
sed -i 's/JSON\./JSONbig./g' node_modules/express/lib/response.js
sed -i "1s/^/var JSONbig = require('json-bigint'); \n/" node_modules/body-parser/lib/types/json.js
sed -i 's/JSON\./JSONbig./g' node_modules/body-parser/lib/types/json.js

Configure

Default settings connect to rinkeby. To override them use environment variables.

• FWD_PRIVATE_KEY - the private key of the forwarder's account
• FWD_ADDRESS - Ethereum address of the forwarder's account
• FWD_JSRPC_ENDPOINT - the endpoint of zksync jsonrpc service
• FWD_GLM_SYMBOL - GNT in rinkeby, GLM in mainnet
• FWD_SUBSIDIZED_FEE_RATE - how much of a fee a client pays, in percent (100 means no subsidies)
• FWD_ZKSYNC_ADDRESS - the address or name of zksync operator, rinkeby or mainnet for instance (needed to instantiate a provider)
• FWD_SERVER_PORT - the port of forwarder

Run

node forwarder.js