embark/lib/modules/solidity/solcP.js

const fs = require('fs-extra');
const path = require('path');
const constants = require('../../constants');
const Utils = require('../../utils/utils');
const ProcessWrapper = require('../../process/processWrapper');
const PluginManager = require('live-plugin-manager-git-fix').PluginManager;
const NpmTimer = require('../../versions/npmTimer');


class SolcProcess extends ProcessWrapper {

  constructor(options){
    super();
    this._logger = options.logger;
    this._npm = options.npm;
  }

  findImports(filename) {
    if (filename.startsWith('http') || filename.startsWith('git')) {
      const fileObj = Utils.getExternalContractUrl(filename);
      filename = fileObj.filePath;
    }
    if (fs.existsSync(filename)) {
      return {contents: fs.readFileSync(filename).toString()};
    }
    if (fs.existsSync(path.join('./node_modules/', filename))) {
      return {contents: fs.readFileSync(path.join('./node_modules/', filename)).toString()};
    }
    if (fs.existsSync(path.join(constants.httpContractsDirectory, filename))) {
      return {contents: fs.readFileSync(path.join(constants.httpContractsDirectory, filename)).toString()};
    }
    return {error: 'File not found'};
  }

  installAndLoadCompiler(solcVersion, packagePath){
    let self = this;
    return new Promise((resolve) => {
      let manager = new PluginManager({pluginsPath: packagePath});
      let timer;
      if (!fs.existsSync(packagePath)) {
        timer = new NpmTimer({logger: self._logger, packageName: 'solc', version: solcVersion, showSpinner: true});
      }

      if(timer) timer.start();
      manager.install('solc', solcVersion).then(() => {
        self.solc = manager.require('solc');
        if(timer) timer.end();
        resolve();
      });
      
    });
  }

  compile(jsonObj, cb) {
    // TODO: only available in 0.4.11; need to make versions warn about this
    try {
      let output = this.solc.compileStandardWrapper(JSON.stringify(jsonObj), this.findImports);
      cb(null, output);
    } catch (err) {
      cb(err.message);
    }
  }


}

let solcProcess;
process.on('message', (msg) => {
  if (msg.action === "init") {
    solcProcess = new SolcProcess(msg.options);
    return process.send({result: "initiated"});
  }

  else if (msg.action === 'loadCompiler') {
    solcProcess.solc = require('solc');
    return process.send({result: "loadedCompiler"});
  }

  else if (msg.action == 'installAndLoadCompiler') {
    solcProcess.installAndLoadCompiler(msg.solcVersion, msg.packagePath).then(() => {
      return process.send({result: "loadedCompiler"});
    });
  }

  else if (msg.action === 'compile') {
    solcProcess.compile(msg.jsonObj, (err, output) => {
      process.send({result: "compilation-" + msg.id, err: err, output: output});
    });
  }
});