Building Blockchain Projects

Writing migrations

At the beginning of a migration file, we tell truffle which contracts we'd like to interact with via the artifacts.require() method. This method is similar to Node's require, but in our case, it specifically returns a contract abstraction that we can use within the rest of our deployment script.

All migrations must export a function via the module.exports syntax. The function exported by each migration should accept a deployer object as its first parameter. This object assists in deployment both by providing a clear API to deploy smart contracts as well as performing some of the deployment's more mundane duties, such as saving deployed artifacts in the artifacts files for later use, linking libraries, and so on. The deployer ...