feat: add after build hooks (#218)

* Adding cli option after-build-hook.

* Specifying initial vs rebuild hooks.

scripts/index.js

@@ -8,6 +8,7 @@ const fs = require('fs-extra');
 const path = require('path');
 const ora = require('ora');
 const assert = require('assert');
+const exec = require('child_process').exec;
 
 const {
   flags: {
@@ -18,6 +19,8 @@ const {
     disableChunks,
     outputFilename,
     chunkFilename,
+    afterInitialBuildHook,
+    afterRebuildHook,
   },
 } = require('../utils/cliHandler');
 const { getReactScriptsVersion, isEjected } = require('../utils');
@@ -91,12 +94,11 @@ if (disableChunks) {
 
 // update media path destination
 if (major >= 4) {
-  const oneOfIndex = 1
+  const oneOfIndex = 1;
   config.module.rules[oneOfIndex].oneOf[0].options.name = `media/[name].[hash:8].[ext]`;
   config.module.rules[oneOfIndex].oneOf[1].options.name = `media/[name].[hash:8].[ext]`;
   config.module.rules[oneOfIndex].oneOf[8].options.name = `media/[name].[hash:8].[ext]`;
-}
-else if (major >= 2) {
+} else if (major >= 2) {
   // 2.0.0 => 2
   // 2.0.1 => 3
   // 2.0.2 => 3
@@ -150,6 +152,9 @@ fs.emptyDir(paths.appBuild)
         }
 
         spinner.succeed();
+
+        runHook('after rebuild hook', spinner, afterRebuildHook);
+
         inProgress = false;
 
         if (verbose) {
@@ -167,7 +172,8 @@ fs.emptyDir(paths.appBuild)
       });
     });
   })
-  .then(() => copyPublicFolder());
+  .then(() => copyPublicFolder())
+  .then(() => runHook('after initial build hook', spinner, afterInitialBuildHook));
 
 function copyPublicFolder() {
   return fs.copy(paths.appPublic, resolvedBuildPath, {
@@ -176,6 +182,24 @@ function copyPublicFolder() {
   });
 }
 
+function runHook(label, spinner, hook) {
+  if (!hook || typeof hook !== 'string') {
+    return;
+  }
+
+  spinner.start(label);
+
+  exec(hook, (error, stdout, stderr) => {
+    if (error) {
+      spinner.fail(`${label}: exec error: ${error}`);
+    } else if (stderr) {
+      spinner.warn(`${label}: ${stderr}`);
+    } else {
+      spinner.succeed(`${label}: ${stdout}`);
+    }
+  });
+}
+
 function handleBuildPath(userBuildPath) {
   if (path.isAbsolute(userBuildPath)) {
     return userBuildPath;

utils/cliHandler.js

@@ -18,6 +18,10 @@ module.exports = meow(
 
       -p, --public-path Public URL.
 
+      --after-rebuild-hook Run a command after each build/rebuild (e.g. 'node ./afterbuild.js')
+
+      --after-initial-build-hook Run a command after each the initial build only (e.g. 'node ./afterbuild.js')
+
       --react-scripts-version Version of the react-scripts package used in your project i.e 2.0.3. If not given it will be implied from your package.json and if it cannot be implied the major version 2 will be the default.
 
       -v, --verbose
@@ -54,6 +58,12 @@ module.exports = meow(
         type: 'boolean',
         alias: 'v',
       },
+      'after-initial-build-hook': {
+        type: 'string',
+      },
+      'after-rebuild-hook': {
+        type: 'string',
+      }
     },
   }
 );