Add basic .env support. (#258)

* Add .env support.

* Handle promise rejection.

* Use process.env.DOTENV

* Use dotenv

* Use dotenv module

* Move env loading to a util, copy to workers, add tests

packages/core/parcel/package.json

@@ -19,6 +19,7 @@
     "commander": "^2.11.0",
     "cross-spawn": "^5.1.0",
     "cssnano": "^3.10.0",
+    "dotenv": "^4.0.0",
     "get-port": "^3.2.0",
     "glob": "^7.1.2",
     "htmlnano": "^0.1.6",

packages/core/parcel/src/Bundler.js

@@ -14,6 +14,7 @@ const PackagerRegistry = require('./packagers');
 const localRequire = require('./utils/localRequire');
 const config = require('./utils/config');
 const emoji = require('./utils/emoji');
+const loadEnv = require('./utils/env');
 
 /**
  * The Bundler is the main entry point. It resolves and loads assets,
@@ -176,8 +177,10 @@ class Bundler extends EventEmitter {
     }
 
     await this.loadPlugins();
+    await loadEnv(this.mainFile);
 
     this.options.extensions = Object.assign({}, this.parser.extensions);
+    this.options.env = process.env;
     this.farm = WorkerFarm.getShared(this.options);
 
     if (this.options.watch) {

packages/core/parcel/src/utils/env.js

@@ -0,0 +1,26 @@
+const config = require('./config');
+const dotenv = require('dotenv');
+
+async function loadEnv(filepath) {
+  const NODE_ENV = process.env.NODE_ENV || 'development';
+  const dotenvFiles = [
+    `.env.${NODE_ENV}.local`,
+    `.env.${NODE_ENV}`,
+    // Don't include `.env.local` for `test` environment
+    // since normally you expect tests to produce the same
+    // results for everyone
+    NODE_ENV !== 'test' && '.env.local',
+    '.env'
+  ].filter(Boolean);
+
+  await Promise.all(
+    dotenvFiles.map(async dotenvFile => {
+      const envPath = await config.resolve(filepath, [dotenvFile]);
+      if (envPath) {
+        dotenv.config({path: envPath});
+      }
+    })
+  );
+}
+
+module.exports = loadEnv;

packages/core/parcel/src/worker.js

@@ -5,6 +5,7 @@ let parser;
 
 exports.init = function(options, callback) {
   parser = new Parser(options || {});
+  Object.assign(process.env, options.env || {});
   callback();
 };
 

packages/core/parcel/test/integration/env-file/.env

@@ -0,0 +1,2 @@
+FOO=bar
+BAR=test

packages/core/parcel/test/integration/env-file/index.js

@@ -0,0 +1 @@
+module.exports = process.env.FOO + process.env.BAR;

packages/core/parcel/test/javascript.js

@@ -222,6 +222,13 @@ describe('javascript', function() {
     assert.equal(output(), 'test:test');
   });
 
+  it('should insert environment variables from a file', async function() {
+    let b = await bundle(__dirname + '/integration/env-file/index.js');
+
+    let output = run(b);
+    assert.equal(output, 'bartest');
+  });
+
   it('should support adding implicit dependencies', async function() {
     let b = await bundle(__dirname + '/integration/json/index.js', {
       delegate: {

yarn.lock

@@ -1621,6 +1621,10 @@ domutils@^1.5.1:
     dom-serializer "0"
     domelementtype "1"
 
+dotenv@^4.0.0:
+  version "4.0.0"
+  resolved "https://registry.yarnpkg.com/dotenv/-/dotenv-4.0.0.tgz#864ef1379aced55ce6f95debecdce179f7a0cd1d"
+
 ecc-jsbn@~0.1.1:
   version "0.1.1"
   resolved "https://registry.yarnpkg.com/ecc-jsbn/-/ecc-jsbn-0.1.1.tgz#0fc73a9ed5f0d53c38193398523ef7e543777505"