Package and Dapp Descriptor Format

Abstract

Successful languages have package management tools which greatly simplify code sharing, which contributes to network effect.
The Ethereum ecosystem is somewhat unique in that everyone shares a global runtime environment, so addresses are both "code-like" and "object-like".

Motivation

We want to ensure we can support the whole spectrum of Solidity packages, especially those that allow working with existing systems:

• Simple static libraries which make no reference to any objects on any chain (ie Math)
• Packages which describe singleton dapps (they ship address references and type info, but don't intend for people to re-use the solidity code, like actual Solidity libraries (string)).
• Packages which describe singleton dapps, with extra support code for interacting with the system (eg something that interacts with a registry)
• Packages which describe dapp "types" which you can deploy, like when an app is too large to build via a factory or requires a complex deployscript (eg a Token system that separates datastore/controller/frontend).

The result is a descriptor file called a dappfile which is similar to npm's package.json but with special attention to handling addresses with special meaning.
dappfiles can be modified in a structured way with "deploy scripts", which is out of scope for this ERC but is described here: https://github.com/nexusdev/dapple/blob/master/doc/deployscript.md

Specification

The dappfile schema is defined here: https://github.com/nexusdev/dapple/blob/master/specs/dappfile.schema.json

Implementation

Sample implementation here: https://github.com/nexusdev/dapple

Example dappfile

name: mydapp
version: 0.1.0
layout:
  sol_sources: contracts
  build: build
environments:
  default: morden
  morden:
     my_dapp_registry:
       address: 0x0...
       type: MyRegistry
  ethereum:
     my_dapp_registry:
         addresss: 0x1...
         type: MyRegistry

Things to discuss

I propose we start by polling to see if there are any unusual use cases which do not fit into the "set of solidity files, plus named sets of sets of named addresses" model.