fix: various nits with process lifetime and streaming

package.json

@@ -20,7 +20,6 @@
     "packages/*"
   ],
   "devDependencies": {
-    "@npmcli/arborist": "^7.3.1",
-    "chalk": "^4.1.2"
+    "@npmcli/arborist": "^7.3.1"
   }
 }

packages/build/build/default.eslint.config.js

@@ -66,6 +66,7 @@ module.exports = async (flecks) => ({
     'import/prefer-default-export': 'off',
     'jsx-a11y/control-has-associated-label': ['error', {assert: 'either'}],
     'jsx-a11y/label-has-associated-control': ['error', {assert: 'either'}],
+    'max-classes-per-file': ['error', {ignoreExpressions: true}],
     'no-param-reassign': ['error', {props: false}],
     'no-plusplus': 'off',
     'no-shadow': 'off',

packages/build/build/hooks/@flecks/build.commands.js

@@ -20,6 +20,7 @@ const {
 } = require('@babel/types');
 const addPathsToYml = require('@flecks/core/build/add-paths-to-yml');
 const D = require('@flecks/core/build/debug');
+const {prefixLines} = require('@flecks/core/build/stream');
 const {
   add,
   binaryPath,
@@ -28,6 +29,7 @@ const {
   spawnWith,
   writeFile,
 } = require('@flecks/core/src/server');
+const chalk = require('chalk');
 const chokidar = require('chokidar');
 const {glob} = require('glob');
 const {paperwork} = require('precinct');
@@ -224,24 +226,43 @@ exports.hook = (program, flecks) => {
           '--mode', (production && !hot) ? 'production' : 'development',
         ];
         const options = {
-          // @todo This kills the pnpm. Let's use a real IPC channel.
-          useFork: true,
+          stdio: ['pipe', 'pipe', 'pipe', 'ipc'],
           ...rest,
           env: {
+            DEBUG_COLORS: process.stdout.isTTY,
             FLECKS_BUILD_IS_PRODUCTION: production,
+            FORCE_COLOR: process.stdout.isTTY,
             ...(target ? {FLECKS_CORE_BUILD_LIST: target} : {}),
             ...(hot ? {FLECKS_ENV__flecks_server__hot: 'true'} : {}),
             ...rest.env,
           },
         };
+        const spawnWithPrefixedLines = (cmd, options) => {
+          const child = spawnWith(cmd, options);
+          if (
+            'pipe' === options.stdio
+            || (Array.isArray(options.stdio) && options.stdio[0] === 'pipe')
+          ) {
+            prefixLines(child.stdout, chalk.green('[📦] '))
+              .pipe(process.stdout);
+          }
+          if (
+            'pipe' === options.stdio
+            || (Array.isArray(options.stdio) && options.stdio[1] === 'pipe')
+          ) {
+            prefixLines(child.stderr, chalk.green('[📦] '))
+              .pipe(process.stderr);
+          }
+          return child;
+        };
         if (!watch) {
-          return spawnWith(cmd, options);
+          return spawnWithPrefixedLines(cmd, options);
         }
         try {
           await access(join(FLECKS_CORE_ROOT, 'build/flecks.yml'));
         }
         catch (error) {
-          return spawnWith(cmd, options);
+          return spawnWithPrefixedLines(cmd, options);
         }
         await rootsDependencies(flecks.roots, flecks.resolver);
         const watched = Object.keys(dependencies);
@@ -259,7 +280,7 @@ exports.hook = (program, flecks) => {
         });
         let webpack;
         const spawnWebpack = () => {
-          webpack = spawnWith(cmd, options);
+          webpack = spawnWithPrefixedLines(cmd, options);
           webpack.on('message', (message) => {
             switch (message.type) {
               case 'kill':

packages/build/package.json

@@ -37,6 +37,7 @@
     "babel-merge": "^3.0.0",
     "chai": "4.2.0",
     "chai-as-promised": "7.1.1",
+    "chalk": "^4.1.2",
     "chokidar": "^3.5.3",
     "commander": "11.1.0",
     "copy-webpack-plugin": "^11.0.0",

packages/core/build/debug.js

@@ -21,7 +21,7 @@ module.exports = (name) => {
       D.formatters.o = undefined;
       D.formatters.O = undefined;
     }
-    const type = 'web' === process.env.FLECKS_CORE_BUILD_TARGET ? 'debug' : 'error';
+    const type = 'undefined' !== typeof window ? 'log' : 'error';
     // eslint-disable-next-line no-console
     D.log = console[type].bind(console);
   }

packages/core/build/stream.js

@@ -1,8 +1,12 @@
 // eslint-disable-next-line max-classes-per-file, import/no-extraneous-dependencies
 const {Buffer} = require('buffer');
+const {EOL} = require('os');
+const {Transform, Writable} = require('stream');
+
 const {dump: dumpYml, load: loadYml} = require('js-yaml');
 const JsonParse = require('jsonparse');
-const {Transform, Writable} = require('stream');
+
+const linebreak = /\r?\n/;
 
 exports.JsonStream = class JsonStream extends Transform {
 
@@ -46,17 +50,43 @@ exports.JsonStream.PrettyPrint = class extends exports.JsonStream {
 
 };
 
-exports.pipesink = (stream) => {
+exports.LineStream = class LineStream extends Transform {
+
+  constructor(encoding = 'utf8') {
+    super();
+    this.encoding = encoding;
+    this.buffer = '';
+  }
+
+  // eslint-disable-next-line no-underscore-dangle
+  _transform(chunk, encoding, done) {
+    const string = chunk.toString(this.encoding);
+    if (!string.match(linebreak)) {
+      this.buffer += string;
+      done();
+      return;
+    }
+    const parts = (this.buffer + string).split(linebreak);
+    this.buffer = parts.pop();
+    for (let i = 0; i < parts.length; ++i) {
+      this.push(parts[i]);
+    }
+    done();
+  }
+
+};
+
+exports.pipesink = (stream, {concat = Buffer.concat} = {}) => {
   class Sink extends Writable {
 
     constructor() {
       super();
-      this.buffers = [];
+      this.chunks = [];
     }
 
     // eslint-disable-next-line no-underscore-dangle
     _write(chunk, encoding, done) {
-      this.buffers.push(chunk);
+      this.chunks.push(chunk);
       done();
     }
 
@@ -66,11 +96,27 @@ exports.pipesink = (stream) => {
     stream.pipe(sink);
     stream.on('error', reject);
     stream.on('end', () => {
-      resolve(Buffer.concat(sink.buffers));
+      resolve(concat(sink.chunks));
     });
   });
 };
 
+exports.prefixLines = (stream, prefix) => (
+  stream
+    .pipe(new exports.LineStream())
+    .pipe(new class Stdio extends Transform {
+
+      // eslint-disable-next-line no-underscore-dangle, class-methods-use-this
+      _transform(chunk, encoding, done) {
+        this.push(prefix);
+        this.push(chunk);
+        this.push(EOL);
+        done();
+      }
+
+    }())
+);
+
 exports.YamlStream = class YamlStream extends Transform {
 
   constructor(decorator, options = {dump: {}, load: {}}) {

packages/core/src/hooks/@flecks/web.config.js

@@ -1,3 +1,4 @@
 exports.hook = async (req, flecks) => ({
   id: flecks.get('@flecks/core.id'),
+  hi: 'foo',
 });

packages/core/src/server/process.js

@@ -1,4 +1,4 @@
-const {exec, fork, spawn} = require('child_process');
+const {exec, spawn} = require('child_process');
 const {
   access,
   constants: {X_OK},
@@ -60,15 +60,14 @@ exports.run = (cmd, {suppressError = true} = {}) => (
 const children = [];
 
 exports.spawnWith = (cmd, opts = {}) => {
-  const {useFork, ...rest} = opts;
-  debug("%sing: '%s'", useFork ? 'fork' : 'spawn', cmd.join(' '));
-  debugSilly('with options: %O', rest);
-  const child = (useFork ? fork : spawn)(cmd[0], cmd.slice(1), {
+  debug("spawning: '%s'", cmd.join(' '));
+  debugSilly('with options: %O', opts);
+  const child = spawn(cmd[0], cmd.slice(1), {
     stdio: 'inherit',
-    ...rest,
+    ...opts,
     env: {
       ...process.env,
-      ...rest.env,
+      ...opts.env,
     },
   });
   children.push(child);

packages/fleck/build/commands.js

@@ -13,7 +13,6 @@ const debug = D('@flecks/build.commands');
 
 const {
   FLECKS_CORE_ROOT = process.cwd(),
-  TERM,
 } = process.env;
 
 module.exports = (program, flecks) => {
@@ -49,7 +48,7 @@ module.exports = (program, flecks) => {
       const filename = await flecks.resolveBuildConfig('test.webpack.config.js', '@flecks/build');
       const config = {test: await require(filename)(env, argv, flecks)};
       await flecks.configureBuilds(config, env, argv);
-      if (!config.test.entry) {
+      if (0 === Object.entries(config.test.entry).length) {
         return undefined;
       }
       // Remove the previous test(s).
@@ -59,8 +58,8 @@ module.exports = (program, flecks) => {
         'test',
         {
           env: {
-            DEBUG_COLORS: 'dumb' !== TERM,
-            FORCE_COLOR: 'dumb' !== TERM,
+            DEBUG_COLORS: process.stdout.isTTY,
+            FORCE_COLOR: process.stdout.isTTY,
           },
           production,
           stdio: watch ? 'inherit' : 'pipe',

packages/server/build/start.js

@@ -1,6 +1,9 @@
 const cluster = require('cluster');
 const {join} = require('path');
 
+const {prefixLines} = require('@flecks/core/build/stream');
+const chalk = require('chalk');
+
 class StartServerPlugin {
 
   pluginName = 'StartServerPlugin';
@@ -27,21 +30,27 @@ class StartServerPlugin {
   apply(compiler) {
     const {options: {exec, signal}, pluginName} = this;
     const logger = compiler.getInfrastructureLogger(pluginName);
+    let lastStartHadErrors = false;
     compiler.hooks.afterEmit.tapPromise(pluginName, async (compilation) => {
+      if (compilation.errors.length > 0) {
+        lastStartHadErrors = true;
+        return;
+      }
       if (this.worker && this.worker.isConnected()) {
-        if (signal) {
+        if (signal && !lastStartHadErrors) {
           process.kill(
             this.worker.process.pid,
             true === signal ? 'SIGUSR2' : signal,
           );
-          return undefined;
+          return;
         }
         const promise = new Promise((resolve) => {
           this.worker.on('disconnect', resolve);
         });
         this.worker.disconnect();
         await promise;
       }
+      lastStartHadErrors = false;
       let entryPoint;
       if (!exec) {
         entryPoint = compilation.getPath(Object.keys(compilation.assets)[0]);
@@ -55,7 +64,7 @@ class StartServerPlugin {
       else {
         entryPoint = exec(compilation);
       }
-      return this.startServer(join(compiler.options.output.path, entryPoint));
+      await this.startServer(join(compiler.options.output.path, entryPoint));
     });
     compiler.hooks.shouldEmit.tap(pluginName, (compilation) => {
       const entryPoints = Object.keys(compilation.assets);
@@ -92,9 +101,16 @@ class StartServerPlugin {
       exec,
       execArgv,
       args,
+      stdio: ['pipe', 'pipe', 'pipe', 'ipc'],
       ...(inspectPort && {inspectPort}),
     });
-    this.worker = cluster.fork(env);
+    this.worker = cluster.fork({
+      ...env,
+    });
+    ['stdout', 'stderr'].forEach((stream) => {
+      prefixLines(this.worker.process[stream], chalk.blue('[SRV] '))
+        .pipe(process[stream]);
+    });
     this.worker.on('exit', (code) => {
       if (killOnExit && !this.worker.exitedAfterDisconnect) {
         process.send({type: 'kill', payload: code});

packages/server/package.json

@@ -23,7 +23,8 @@
     "server.js"
   ],
   "dependencies": {
-    "@flecks/core": "^4.2.3"
+    "@flecks/core": "^4.2.3",
+    "chalk": "^4.1.2"
   },
   "devDependencies": {
     "@flecks/build": "^4.1.3",

packages/server/test/helpers/start-server.js

@@ -15,7 +15,6 @@ import {createApplication} from './create-application';
 
 const {
   FLECKS_CORE_ROOT = process.cwd(),
-  TERM,
 } = process.env;
 
 class SocketWrapper {
@@ -135,12 +134,10 @@ export async function startServer({
     stdio: 'pipe',
     ...opts,
     env: {
-      DEBUG_COLORS: 'dumb' !== TERM,
       FLECKS_ENV__flecks_server__stats: '{"preset": "none"}',
       FLECKS_ENV__flecks_server__start: true,
       FLECKS_CORE_ROOT: path,
       FLECKS_SERVER_TEST_SOCKET: socketPath,
-      FORCE_COLOR: 'dumb' !== TERM,
       NODE_ENV: 'test',
       NODE_PATH: join(FLECKS_CORE_ROOT, '..', '..', 'node_modules'),
       ...opts.env,

packages/web/build/hooks/@flecks/core.config.js

@@ -15,6 +15,10 @@ exports.hook = () => ({
    * (webpack-dev-server) Port to bind. Defaults to random port.
    */
   devPort: 0,
+  /**
+   * (webpack-dev-server) Set up a proxy to the dev server. Defaults to `false` in production.
+   */
+  devProxyWds: undefined,
   /**
    * (webpack-dev-server) Webpack stats output.
    */

packages/web/package.json

@@ -38,6 +38,7 @@
     "before-build-webpack": "^0.2.13",
     "browserify-zlib": "^0.2.0",
     "buffer": "^6.0.3",
+    "chalk": "^4.1.2",
     "clean-webpack-plugin": "4.0.0",
     "compression": "^1.7.4",
     "css-loader": "^6.8.1",