// Require and configure EthPM relative to a package location on disk.
// `host` and `registry` must conform to Javascript Host and Registry interface.
// A "host" is a service that holds the files, like IPFS. A "registry" is a
// service that records package versions that have been published and their
// associated lockfile on the host.
var EthPM = require("ethpm");
var config = EthPM.configure(package_directory, host, registry);

// Install a single package into the current package, denoted by name and version.
// Returns a promise.
EthPM.installDependency(config, package_name, version_range);

// Install all dependencies of the current package.
// Returns a promise.
EthPM.installPackage(config);

// Publish the current package.
// Returns a promise.
// `contract_metadata` is information about published contracts you'd like include
// in this package. See lockfile spec for more information.
EthPM.publishPackage(config, contract_metadata);