From 5f390fc065c546b7b6f411c6c32ffaa0b3687147 Mon Sep 17 00:00:00 2001
From: Seth Foster <seth@opentrons.com>
Date: Wed, 8 May 2024 09:35:53 -0400
Subject: [PATCH] fix(app-shell-odd): allow running offboard (#15105)

It's useful to be able to run the odd shell on your laptop for testing
flows, and this code baked in a bunch of directory structure
assumptions. These fixes hopefully tolerate the changes by falling back
to not scanning for file changes anymore, allowing you to once again run
make -C app dev-odd.
---
 app-shell-odd/src/usb.ts | 68 ++++++++++++++++++++++------------------
 1 file changed, 38 insertions(+), 30 deletions(-)

diff --git a/app-shell-odd/src/usb.ts b/app-shell-odd/src/usb.ts
index 69629eff161..ebfd8bb7f42 100644
--- a/app-shell-odd/src/usb.ts
+++ b/app-shell-odd/src/usb.ts
@@ -90,40 +90,48 @@ export function watchForMassStorage(dispatch: Dispatch): () => void {
         prevDirs = present.filter((entry): entry is string => entry !== null)
       })
 
-  const mediaWatcher = fs.watch(
-    FLEX_USB_MOUNT_DIR,
-    { persistent: true },
-    (event, fileName) => {
-      if (!!!fileName) {
-        rescan(dispatch)
-        return
-      }
-      if (!fileName.match(FLEX_USB_MOUNT_FILTER)) {
-        return
-      }
-      const fullPath = join(FLEX_USB_MOUNT_DIR, fileName)
-      fsPromises
-        .stat(fullPath)
-        .then(info => {
-          if (!info.isDirectory) {
+  const mediaWatcherCreator = (): fs.FSWatcher | null => {
+    try {
+      return fs.watch(
+        FLEX_USB_MOUNT_DIR,
+        { persistent: true },
+        (event, fileName) => {
+          if (!!!fileName) {
+            rescan(dispatch)
             return
           }
-          if (prevDirs.includes(fullPath)) {
+          if (!fileName.match(FLEX_USB_MOUNT_FILTER)) {
             return
           }
-          console.log(`New mass storage device ${fileName} detected`)
-          prevDirs.push(fullPath)
-          return handleNewlyPresent(fullPath)
-        })
-        .catch(() => {
-          if (prevDirs.includes(fullPath)) {
-            console.log(`Mass storage device at ${fileName} removed`)
-            prevDirs = prevDirs.filter(entry => entry !== fullPath)
-            dispatch(robotMassStorageDeviceRemoved(fullPath))
-          }
-        })
+          const fullPath = join(FLEX_USB_MOUNT_DIR, fileName)
+          fsPromises
+            .stat(fullPath)
+            .then(info => {
+              if (!info.isDirectory) {
+                return
+              }
+              if (prevDirs.includes(fullPath)) {
+                return
+              }
+              console.log(`New mass storage device ${fileName} detected`)
+              prevDirs.push(fullPath)
+              return handleNewlyPresent(fullPath)
+            })
+            .catch(() => {
+              if (prevDirs.includes(fullPath)) {
+                console.log(`Mass storage device at ${fileName} removed`)
+                prevDirs = prevDirs.filter(entry => entry !== fullPath)
+                dispatch(robotMassStorageDeviceRemoved(fullPath))
+              }
+            })
+        }
+      )
+    } catch {
+      return null
     }
-  )
+  }
+
+  const mediaWatcher = mediaWatcherCreator()
 
   const devWatcher = fs.watch(
     FLEX_USB_DEVICE_DIR,
@@ -150,7 +158,7 @@ export function watchForMassStorage(dispatch: Dispatch): () => void {
 
   rescan(dispatch)
   return () => {
-    mediaWatcher.close()
+    mediaWatcher != null && mediaWatcher.close()
     devWatcher.close()
   }
 }