From 38ff9faff639385c10ccb6412470e1355c73327c Mon Sep 17 00:00:00 2001
From: David Sherret <dsherret@users.noreply.github.com>
Date: Fri, 31 May 2024 23:25:08 -0400
Subject: [PATCH] fix: retry writing lockfile on failure (#24052)

Ran into this running the deno_graph ecosystem tests where many
processes writing to the same path at the same time would cause an
error.
---
 cli/args/lockfile.rs |  4 ++--
 cli/util/fs.rs       | 29 +++++++++++++++++++++++++++--
 2 files changed, 29 insertions(+), 4 deletions(-)

diff --git a/cli/args/lockfile.rs b/cli/args/lockfile.rs
index 30e91eb92a..7e59853b0f 100644
--- a/cli/args/lockfile.rs
+++ b/cli/args/lockfile.rs
@@ -8,7 +8,7 @@ use deno_runtime::deno_node::PackageJson;
 
 use crate::args::ConfigFile;
 use crate::cache;
-use crate::util::fs::atomic_write_file;
+use crate::util::fs::atomic_write_file_with_retries;
 use crate::Flags;
 
 use super::DenoSubcommand;
@@ -84,7 +84,7 @@ pub fn write_lockfile_if_has_changes(
   };
   // do an atomic write to reduce the chance of multiple deno
   // processes corrupting the file
-  atomic_write_file(&lockfile.filename, bytes, cache::CACHE_PERM)
+  atomic_write_file_with_retries(&lockfile.filename, bytes, cache::CACHE_PERM)
     .context("Failed writing lockfile.")?;
   lockfile.has_content_changed = false;
   Ok(())
diff --git a/cli/util/fs.rs b/cli/util/fs.rs
index 9bdb1d014e..5adb777b03 100644
--- a/cli/util/fs.rs
+++ b/cli/util/fs.rs
@@ -32,6 +32,28 @@ use crate::util::progress_bar::ProgressBar;
 use crate::util::progress_bar::ProgressBarStyle;
 use crate::util::progress_bar::ProgressMessagePrompt;
 
+pub fn atomic_write_file_with_retries<T: AsRef<[u8]>>(
+  file_path: &Path,
+  data: T,
+  mode: u32,
+) -> std::io::Result<()> {
+  let mut count = 0;
+  loop {
+    match atomic_write_file(file_path, data.as_ref(), mode) {
+      Ok(()) => return Ok(()),
+      Err(err) => {
+        if count >= 5 {
+          // too many retries, return the error
+          return Err(err);
+        }
+        count += 1;
+        let sleep_ms = std::cmp::min(50, 10 * count);
+        std::thread::sleep(std::time::Duration::from_millis(sleep_ms));
+      }
+    }
+  }
+}
+
 /// Writes the file to the file system at a temporary path, then
 /// renames it to the destination in a single sys call in order
 /// to never leave the file system in a corrupted state.
@@ -50,8 +72,11 @@ pub fn atomic_write_file<T: AsRef<[u8]>>(
     mode: u32,
   ) -> std::io::Result<()> {
     write_file(temp_file_path, data, mode)?;
-    std::fs::rename(temp_file_path, file_path)?;
-    Ok(())
+    std::fs::rename(temp_file_path, file_path).map_err(|err| {
+      // clean up the created temp file on error
+      let _ = std::fs::remove_file(temp_file_path);
+      err
+    })
   }
 
   fn inner(file_path: &Path, data: &[u8], mode: u32) -> std::io::Result<()> {