From 77210c154add1f29604478bb3805cce979e67555 Mon Sep 17 00:00:00 2001
From: Yuki Hattori <yukihattori1116@gmail.com>
Date: Mon, 20 Jan 2025 00:18:17 +0900
Subject: [PATCH 1/2] Update `Server#convertMarkdown` to return  processed type

---
 src/server.ts | 24 ++++++++++++------------
 1 file changed, 12 insertions(+), 12 deletions(-)

diff --git a/src/server.ts b/src/server.ts
index b2249ec7..73d04f95 100644
--- a/src/server.ts
+++ b/src/server.ts
@@ -88,9 +88,7 @@ export class Server extends (EventEmitter as new () => TypedEmitter<Server.Event
     filename: string,
     query: querystring.ParsedUrlQuery = {}
   ) {
-    this.converter.options.output = false
-    this.converter.options.pages = false
-    this.converter.options.type = ((): ConvertType => {
+    const type = ((): ConvertType => {
       const queryKeys = Object.keys(query)
 
       if (queryKeys.includes('pdf')) return ConvertType.pdf
@@ -104,10 +102,14 @@ export class Server extends (EventEmitter as new () => TypedEmitter<Server.Event
       return ConvertType.html
     })()
 
-    const ret = await this.converter.convertFile(new File(filename))
-    this.emit('converted', ret)
+    this.converter.options.output = false
+    this.converter.options.pages = false
+    this.converter.options.type = type
+
+    const result = await this.converter.convertFile(new File(filename))
+    this.emit('converted', result)
 
-    return ret
+    return { result, type }
   }
 
   private async loadScript() {
@@ -127,20 +129,18 @@ export class Server extends (EventEmitter as new () => TypedEmitter<Server.Event
     if (!pathname) return
 
     const qs = querystring.parse(query || '')
-    const response = async (fn) => {
+    const response = async (fn: string) => {
       try {
-        const ret = await this.convertMarkdown(fn, qs)
+        const { result, type } = await this.convertMarkdown(fn, qs)
 
-        if (!ret.newFile)
+        if (!result.newFile)
           throw new Error('Converter must return a converted file to serve.')
 
-        const { type } = this.converter.options
-
         // Download pptx document as an attachment
         if (type === ConvertType.pptx)
           res.attachment(`${path.basename(fn, path.extname(fn))}.pptx`)
 
-        res.type(mimeTypes[type]).end(ret.newFile.buffer)
+        res.type(mimeTypes[type]).end(result.newFile.buffer)
       } catch (e: unknown) {
         let errorString = 'Internal server error'
 

From 037ee4d19efedec62bf0448734d0282e1b3d3fb5 Mon Sep 17 00:00:00 2001
From: Yuki Hattori <yukihattori1116@gmail.com>
Date: Mon, 20 Jan 2025 00:48:01 +0900
Subject: [PATCH 2/2] [ci skip] CHANGELOG.md

---
 CHANGELOG.md | 1 +
 1 file changed, 1 insertion(+)

diff --git a/CHANGELOG.md b/CHANGELOG.md
index fa9b6267..a1cb0984 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -6,6 +6,7 @@
 
 - Improve LibreOffice handling in experimental `--pptx-editable` option ([#632](https://github.com/marp-team/marp-cli/pull/632))
   - Detect LibreOffice automatically that was installed in Windows by Scoop ([#631](https://github.com/marp-team/marp-cli/issues/631), [#632](https://github.com/marp-team/marp-cli/pull/632))
+- Fix returning wrong file extension in concurrent requests on server mode ([#633](https://github.com/marp-team/marp-cli/issues/633), [#634](https://github.com/marp-team/marp-cli/pull/634))
 
 ## v4.1.0 - 2025-01-15