Compress report content with gzip before publishing

CHANGELOG.md

@@ -8,6 +8,8 @@ and this project adheres to [Semantic Versioning](http://semver.org/).
 Please see [CONTRIBUTING.md](./CONTRIBUTING.md) on how to contribute to Cucumber.
 
 ## [Unreleased]
+### Changed
+- Compress report content with gzip before publishing ([#2687](https://github.com/cucumber/cucumber-js/pull/2687))
 
 ## [12.3.0] - 2025-12-01
 ### Added

features/step_definitions/report_server_steps.ts

@@ -1,5 +1,6 @@
 import { URL } from 'node:url'
 import assert from 'node:assert'
+import { gunzipSync } from 'node:zlib'
 import { expect } from 'chai'
 import { Given, Then, DataTable } from '../..'
 import { World } from '../support/world'
@@ -30,7 +31,7 @@ Then(
       .map((row) => row[0])
 
     const receivedBodies = await this.reportServer.stop()
-    const ndjson = receivedBodies.toString('utf-8').trim()
+    const ndjson = gunzipSync(receivedBodies).toString('utf-8').trim()
     if (ndjson === '') assert.fail('Server received nothing')
 
     const receivedMessageTypes = ndjson

src/publish/publish_plugin.ts

@@ -1,9 +1,11 @@
 import { Writable } from 'node:stream'
+import { pipeline } from 'node:stream/promises'
 import { stripVTControlCharacters } from 'node:util'
 import { mkdtemp, stat } from 'node:fs/promises'
 import path from 'node:path'
 import { tmpdir } from 'node:os'
 import { createReadStream, createWriteStream } from 'node:fs'
+import { createGzip } from 'node:zlib'
 import { supportsColor } from 'supports-color'
 import hasAnsi from 'has-ansi'
 import { InternalPlugin } from '../plugin'
@@ -44,22 +46,32 @@ export const publishPlugin: InternalPlugin<IPublishConfig | false> = {
 
     const uploadUrl = touchResponse.headers.get('Location')
     const tempDir = await mkdtemp(path.join(tmpdir(), `cucumber-js-publish-`))
-    const tempFilePath = path.join(tempDir, 'envelopes.ndjson')
-    const tempFileStream = createWriteStream(tempFilePath, {
-      encoding: 'utf-8',
-    })
-    on('message', (value) => tempFileStream.write(JSON.stringify(value) + '\n'))
+    const tempFilePath = path.join(tempDir, 'envelopes.jsonl.gz')
+    const writeStream = createGzip()
+    const finishedWriting = pipeline(
+      writeStream,
+      createWriteStream(tempFilePath)
+    )
+    on('message', (value) => writeStream.write(JSON.stringify(value) + '\n'))
 
     return () => {
       return new Promise<void>((resolve) => {
-        tempFileStream.end(async () => {
+        writeStream.end(async () => {
+          await finishedWriting
           const stats = await stat(tempFilePath)
+          const contentLength = stats.size.toString()
+          logger.debug(
+            'Uploading envelopes to Cucumber Reports with content length:',
+            contentLength
+          )
           const uploadResponse = await fetch(uploadUrl, {
             method: 'PUT',
             headers: {
-              'Content-Length': stats.size.toString(),
+              'Content-Type': 'application/jsonl',
+              'Content-Encoding': 'gzip',
+              'Content-Length': contentLength,
             },
-            body: createReadStream(tempFilePath, { encoding: 'utf-8' }),
+            body: createReadStream(tempFilePath),
             duplex: 'half',
           })
           if (uploadResponse.ok) {
@@ -72,7 +84,7 @@ export const publishPlugin: InternalPlugin<IPublishConfig | false> = {
                 new URL(uploadUrl).origin
               } with status ${uploadResponse.status}`
             )
-            logger.debug(uploadResponse)
+            logger.debug(await uploadResponse.text())
           }
           resolve()
         })