Skip empty files when uploading individual files

node-src/lib/uploadFiles.ts

@@ -5,6 +5,7 @@ import { createReadStream } from 'fs';
 import pLimit from 'p-limit';
 import progress from 'progress-stream';
 import { Context, FileDesc, TargetInfo } from '../types';
+import skippingEmptyFiles from '../ui/messages/warnings/skippingEmptyFiles';
 
 export async function uploadFiles(
   ctx: Context,
@@ -15,8 +16,14 @@ export async function uploadFiles(
   const limitConcurrency = pLimit(10);
   let totalProgress = 0;
 
+  const nonEmptyTargets = targets.filter(({ contentLength }) => contentLength > 0);
+  if (nonEmptyTargets.length !== targets.length) {
+    const emptyFiles = targets.filter(({ contentLength }) => contentLength === 0);
+    ctx.log.warn(skippingEmptyFiles({ emptyFiles }));
+  }
+
   await Promise.all(
-    targets.map(({ contentLength, filePath, formAction, formFields, localPath }) => {
+    nonEmptyTargets.map(({ contentLength, filePath, formAction, formFields, localPath }) => {
       let fileProgress = 0; // The bytes uploaded for this this particular file
 
       ctx.log.debug(`Uploading ${filePath} (${filesize(contentLength)})`);

node-src/ui/messages/warnings/skippingEmptyFiles.stories.ts

@@ -0,0 +1,14 @@
+import skippingEmptyFiles from './skippingEmptyFiles';
+
+export default {
+  title: 'CLI/Messages/Warnings',
+};
+
+export const SkippingEmptyFiles = () =>
+  skippingEmptyFiles({
+    emptyFiles: Array.from({ length: 3 }, (_, i) => ({
+      contentLength: 0,
+      localPath: `file${i}.js`,
+      targetPath: `file${i}.js`,
+    })),
+  });

node-src/ui/messages/warnings/skippingEmptyFiles.ts

@@ -0,0 +1,17 @@
+import chalk from 'chalk';
+import pluralize from 'pluralize';
+import { dedent } from 'ts-dedent';
+
+import { warning } from '../../components/icons';
+import { FileDesc } from '../../../types';
+
+export default ({ emptyFiles }: { emptyFiles: FileDesc[] }) => {
+  const listing = chalk`\n{dim →} ${emptyFiles.map((f) => f.targetPath).join(chalk`\n{dim →} `)}`;
+  return dedent(chalk`
+    ${warning} {bold Not uploading empty files}
+    Found ${pluralize('empty files', emptyFiles.length, true)} in your built Storybook:${listing}
+    Uploading empty files is not supported except when using a zip file.
+    You can ignore this warning if your Storybook doesn't need these files.
+    Otherwise, configure Chromatic with the {bold zip} option.
+  `);
+};