perf(cache): single cache file for remote modules (#24983)

This changes the global cache to store the cache file for remote modules
in one file instead of two.

6 files changed, 71 insertions, 84 deletions

diff --git a/cli/cache/mod.rs b/cli/cache/mod.rs
index 772d2359d..cc183530d 100644
--- a/cli/cache/mod.rs
+++ b/cli/cache/mod.rs
@@ -62,12 +62,8 @@ pub const CACHE_PERM: u32 = 0o644;
 pub struct RealDenoCacheEnv;
 
 impl deno_cache_dir::DenoCacheEnv for RealDenoCacheEnv {
-  fn read_file_bytes(&self, path: &Path) -> std::io::Result<Option<Vec<u8>>> {
-    match std::fs::read(path) {
-      Ok(s) => Ok(Some(s)),
-      Err(err) if err.kind() == std::io::ErrorKind::NotFound => Ok(None),
-      Err(err) => Err(err),
-    }
+  fn read_file_bytes(&self, path: &Path) -> std::io::Result<Vec<u8>> {
+    std::fs::read(path)
   }
 
   fn atomic_write_file(
diff --git a/cli/factory.rs b/cli/factory.rs
index 25f6afa74..224984643 100644
--- a/cli/factory.rs
+++ b/cli/factory.rs
@@ -304,8 +304,11 @@ impl CliFactory {
       let global_cache = self.global_http_cache()?.clone();
       match self.cli_options()?.vendor_dir_path() {
         Some(local_path) => {
-          let local_cache =
-            LocalHttpCache::new(local_path.clone(), global_cache);
+          let local_cache = LocalHttpCache::new(
+            local_path.clone(),
+            global_cache,
+            deno_cache_dir::GlobalToLocalCopy::Allow,
+          );
           Ok(Arc::new(local_cache))
         }
         None => Ok(global_cache),
diff --git a/cli/file_fetcher.rs b/cli/file_fetcher.rs
index 19acf2e2b..ace4d3c7e 100644
--- a/cli/file_fetcher.rs
+++ b/cli/file_fetcher.rs
@@ -11,7 +11,6 @@ use crate::http_util::HttpClientProvider;
 use crate::util::progress_bar::ProgressBar;
 
 use deno_ast::MediaType;
-use deno_core::anyhow::bail;
 use deno_core::anyhow::Context;
 use deno_core::error::custom_error;
 use deno_core::error::generic_error;
@@ -52,6 +51,25 @@ pub enum FileOrRedirect {
   Redirect(ModuleSpecifier),
 }
 
+impl FileOrRedirect {
+  fn from_deno_cache_entry(
+    specifier: &ModuleSpecifier,
+    cache_entry: deno_cache_dir::CacheEntry,
+  ) -> Result<Self, AnyError> {
+    if let Some(redirect_to) = cache_entry.metadata.headers.get("location") {
+      let redirect =
+        deno_core::resolve_import(redirect_to, specifier.as_str())?;
+      Ok(FileOrRedirect::Redirect(redirect))
+    } else {
+      Ok(FileOrRedirect::File(File {
+        specifier: specifier.clone(),
+        maybe_headers: Some(cache_entry.metadata.headers),
+        source: Arc::from(cache_entry.content),
+      }))
+    }
+  }
+}
+
 /// A structure representing a source file.
 #[derive(Debug, Clone, Eq, PartialEq)]
 pub struct File {
@@ -238,45 +256,32 @@ impl FileFetcher {
     );
 
     let cache_key = self.http_cache.cache_item_key(specifier)?; // compute this once
-    let Some(headers) = self.http_cache.read_headers(&cache_key)? else {
-      return Ok(None);
-    };
-    if let Some(redirect_to) = headers.get("location") {
-      let redirect =
-        deno_core::resolve_import(redirect_to, specifier.as_str())?;
-      return Ok(Some(FileOrRedirect::Redirect(redirect)));
-    }
-    let result = self.http_cache.read_file_bytes(
+    let result = self.http_cache.get(
       &cache_key,
       maybe_checksum
         .as_ref()
         .map(|c| deno_cache_dir::Checksum::new(c.as_str())),
-      deno_cache_dir::GlobalToLocalCopy::Allow,
     );
-    let bytes = match result {
-      Ok(Some(bytes)) => bytes,
-      Ok(None) => return Ok(None),
+    match result {
+      Ok(Some(cache_data)) => Ok(Some(FileOrRedirect::from_deno_cache_entry(
+        specifier, cache_data,
+      )?)),
+      Ok(None) => Ok(None),
       Err(err) => match err {
-        deno_cache_dir::CacheReadFileError::Io(err) => return Err(err.into()),
+        deno_cache_dir::CacheReadFileError::Io(err) => Err(err.into()),
         deno_cache_dir::CacheReadFileError::ChecksumIntegrity(err) => {
           // convert to the equivalent deno_graph error so that it
           // enhances it if this is passed to deno_graph
-          return Err(
+          Err(
             deno_graph::source::ChecksumIntegrityError {
               actual: err.actual,
               expected: err.expected,
             }
             .into(),
-          );
+          )
         }
       },
-    };
-
-    Ok(Some(FileOrRedirect::File(File {
-      specifier: specifier.clone(),
-      maybe_headers: Some(headers),
-      source: Arc::from(bytes),
-    })))
+    }
   }
 
   /// Convert a data URL into a file, resulting in an error if the URL is
@@ -363,12 +368,30 @@ impl FileFetcher {
       );
     }
 
-    let maybe_etag = self
+    let maybe_etag_cache_entry = self
       .http_cache
       .cache_item_key(specifier)
       .ok()
-      .and_then(|key| self.http_cache.read_headers(&key).ok().flatten())
-      .and_then(|headers| headers.get("etag").cloned());
+      .and_then(|key| {
+        self
+          .http_cache
+          .get(
+            &key,
+            maybe_checksum
+              .as_ref()
+              .map(|c| deno_cache_dir::Checksum::new(c.as_str())),
+          )
+          .ok()
+          .flatten()
+      })
+      .and_then(|cache_entry| {
+        cache_entry
+          .metadata
+          .headers
+          .get("etag")
+          .cloned()
+          .map(|etag| (cache_entry, etag))
+      });
     let maybe_auth_token = self.auth_tokens.get(specifier);
 
     async fn handle_request_or_server_error(
@@ -390,7 +413,6 @@ impl FileFetcher {
       }
     }
 
-    let mut maybe_etag = maybe_etag;
     let mut retried = false; // retry intermittent failures
     let result = loop {
       let result = match self
@@ -399,31 +421,17 @@ impl FileFetcher {
         .fetch_no_follow(FetchOnceArgs {
           url: specifier.clone(),
           maybe_accept: maybe_accept.map(ToOwned::to_owned),
-          maybe_etag: maybe_etag.clone(),
+          maybe_etag: maybe_etag_cache_entry
+            .as_ref()
+            .map(|(_, etag)| etag.clone()),
           maybe_auth_token: maybe_auth_token.clone(),
           maybe_progress_guard: maybe_progress_guard.as_ref(),
         })
         .await?
       {
         FetchOnceResult::NotModified => {
-          let file_or_redirect =
-            self.fetch_cached_no_follow(specifier, maybe_checksum)?;
-          match file_or_redirect {
-            Some(file_or_redirect) => Ok(file_or_redirect),
-            None => {
-              // Someone may have deleted the body from the cache since
-              // it's currently stored in a separate file from the headers,
-              // so delete the etag and try again
-              if maybe_etag.is_some() {
-                debug!("Cache body not found. Trying again without etag.");
-                maybe_etag = None;
-                continue;
-              } else {
-                // should never happen
-                bail!("Your deno cache directory is in an unrecoverable state. Please delete it and try again.")
-              }
-            }
-          }
+          let (cache_entry, _) = maybe_etag_cache_entry.unwrap();
+          FileOrRedirect::from_deno_cache_entry(specifier, cache_entry)
         }
         FetchOnceResult::Redirect(redirect_url, headers) => {
           self.http_cache.set(specifier, headers, &[])?;
@@ -1480,13 +1488,10 @@ mod tests {
     let cache_key = file_fetcher.http_cache.cache_item_key(url).unwrap();
     let bytes = file_fetcher
       .http_cache
-      .read_file_bytes(
-        &cache_key,
-        None,
-        deno_cache_dir::GlobalToLocalCopy::Allow,
-      )
+      .get(&cache_key, None)
       .unwrap()
-      .unwrap();
+      .unwrap()
+      .content;
     String::from_utf8(bytes).unwrap()
   }
 
diff --git a/cli/lsp/cache.rs b/cli/lsp/cache.rs
index 5dae38c20..d3c05ca91 100644
--- a/cli/lsp/cache.rs
+++ b/cli/lsp/cache.rs
@@ -17,16 +17,6 @@ use std::path::Path;
 use std::sync::Arc;
 use std::time::SystemTime;
 
-/// In the LSP, we disallow the cache from automatically copying from
-/// the global cache to the local cache for technical reasons.
-///
-/// 1. We need to verify the checksums from the lockfile are correct when
-///    moving from the global to the local cache.
-/// 2. We need to verify the checksums for JSR https specifiers match what
-///    is found in the package's manifest.
-pub const LSP_DISALLOW_GLOBAL_TO_LOCAL_COPY: deno_cache_dir::GlobalToLocalCopy =
-  deno_cache_dir::GlobalToLocalCopy::Disallow;
-
 pub fn calculate_fs_version(
   cache: &LspCache,
   specifier: &ModuleSpecifier,
diff --git a/cli/lsp/documents.rs b/cli/lsp/documents.rs
index a8ddc8fd7..80c5a4dc5 100644
--- a/cli/lsp/documents.rs
+++ b/cli/lsp/documents.rs
@@ -2,7 +2,6 @@
 
 use super::cache::calculate_fs_version;
 use super::cache::LspCache;
-use super::cache::LSP_DISALLOW_GLOBAL_TO_LOCAL_COPY;
 use super::config::Config;
 use super::resolver::LspResolver;
 use super::testing::TestCollector;
@@ -872,22 +871,19 @@ impl FileSystemDocuments {
     } else {
       let http_cache = cache.for_specifier(file_referrer);
       let cache_key = http_cache.cache_item_key(specifier).ok()?;
-      let bytes = http_cache
-        .read_file_bytes(&cache_key, None, LSP_DISALLOW_GLOBAL_TO_LOCAL_COPY)
-        .ok()??;
-      let specifier_headers = http_cache.read_headers(&cache_key).ok()??;
+      let cached_file = http_cache.get(&cache_key, None).ok()??;
       let (_, maybe_charset) =
         deno_graph::source::resolve_media_type_and_charset_from_headers(
           specifier,
-          Some(&specifier_headers),
+          Some(&cached_file.metadata.headers),
         );
       let content = deno_graph::source::decode_owned_source(
         specifier,
-        bytes,
+        cached_file.content,
         maybe_charset,
       )
       .ok()?;
-      let maybe_headers = Some(specifier_headers);
+      let maybe_headers = Some(cached_file.metadata.headers);
       Document::new(
         specifier.clone(),
         content.into(),
diff --git a/cli/lsp/jsr.rs b/cli/lsp/jsr.rs
index 9ffcdf9e6..c0a82383d 100644
--- a/cli/lsp/jsr.rs
+++ b/cli/lsp/jsr.rs
@@ -258,12 +258,9 @@ fn read_cached_url(
   cache: &Arc<dyn HttpCache>,
 ) -> Option<Vec<u8>> {
   cache
-    .read_file_bytes(
-      &cache.cache_item_key(url).ok()?,
-      None,
-      deno_cache_dir::GlobalToLocalCopy::Disallow,
-    )
+    .get(&cache.cache_item_key(url).ok()?, None)
     .ok()?
+    .map(|f| f.content)
 }
 
 #[derive(Debug)]