More esbuild fixes (#5618)

esbuild.dev.mjs

@@ -3,7 +3,7 @@ import * as esbuild from 'esbuild';
 // Fetch 'RELATIVE_URL_ROOT' ENV variable value while removing any trailing slashes.
 const relativeUrlRoot = (process.env.RELATIVE_URL_ROOT || '').replace(/\/*$/, '');
 
-await esbuild.build({
+esbuild.context({
   entryPoints: ['app/javascript/main.jsx'],
   bundle: true,
   sourcemap: true,
@@ -12,16 +12,22 @@ await esbuild.build({
     '.png': 'dataurl',
     '.svg': 'text',
   },
-  watch: {
-    onRebuild: (error, result) => {
-      if (error) console.error('watch build failed:', error);
-      else console.log('watch build succeeded:', result);
-    },
-  },
   define: {
     'process.env.RELATIVE_URL_ROOT': `"${relativeUrlRoot}"`,
     'process.env.OMNIAUTH_PATH': `"${relativeUrlRoot}/auth/openid_connect"`, // currently, only OIDC is implemented
   },
-});
-
-console.log('watch build started');
+}).then(context => {
+  if (process.argv.includes("--watch")) {
+    // Enable watch mode
+    context.watch()
+  } else {
+    // Build once and exit if not in watch mode
+    context.rebuild().then(result => {
+      context.dispose()
+    })
+  }
+  console.log('build succeeded');
+}).catch((e) => {
+  console.error('build failed:', e);
+  process.exit(1)
+})

package.json

@@ -41,7 +41,7 @@
   "scripts": {
     "build": "node esbuild.mjs",
     "build:css": "sass ./app/assets/stylesheets/application.bootstrap.scss ./app/assets/builds/application.css --no-source-map --load-path=node_modules --style compressed",
-    "build:development": "node esbuild.dev.mjs",
+    "build:development": "node esbuild.dev.mjs --watch",
     "build:development:css": "sass ./app/assets/stylesheets/application.bootstrap.scss ./app/assets/builds/application.css --no-source-map --load-path=node_modules"
   },
   "devDependencies": {