refactor(cache): redesign cache system with structured keys and improved performance

- Add repo_path parameter to cached_response and cached_vec_response functions
- Implement structured cache key format with namespace, repo_path, and request proto
- Replace global cache with Moka in-memory cache using weight-based eviction
- Set 256MB memory cap with 10-minute TTL and 2-minute TTI policy
- Add metrics collection for cache operations and evictions
- Implement efficient repo-scoped invalidation using key structure
- Add detailed documentation comments explaining cache architecture
- Remove outdated dependencies and update dependency versions
- Add error handling for encoding failures in cache operations
- Optimize Vec responses with length-delimited encoding and pre-allocation

repository/search_files.rs

@@ -2,23 +2,29 @@ use crate::bare::GitBare;
 use crate::error::GitResult;
 use crate::pb::*;
 
+const MAX_SEARCH_RESULTS: u32 = 1000;
+
 impl GitBare {
     /// Search file contents with a regex pattern.
     pub fn search_files_by_content(
         &self,
         request: SearchFilesByContentRequest,
     ) -> GitResult<SearchFilesByContentResponse> {
-        crate::sanitize::validate_revision(&request.revision)?;
-
         let revision = if request.revision.is_empty() {
             "HEAD"
         } else {
             &request.revision
         };
+        crate::sanitize::validate_revision(revision)?;
+        if request.query.is_empty() {
+            return Err(crate::error::GitError::InvalidArgument(
+                "search query cannot be empty".into(),
+            ));
+        }
         let max_results = if request.max_results == 0 {
             100
         } else {
-            request.max_results
+            request.max_results.min(MAX_SEARCH_RESULTS)
         };
 
         let mut args = vec![
@@ -51,6 +57,12 @@ impl GitBare {
             })?;
 
         // git grep returns exit code 1 when no matches found — that's not an error
+        if !output.status.success() && output.status.code() != Some(1) {
+            return Err(crate::error::GitError::CommandFailed {
+                status_code: output.status.code(),
+                stderr: String::from_utf8_lossy(&output.stderr).trim().to_string(),
+            });
+        }
         let stdout = String::from_utf8_lossy(&output.stdout);
         let mut results = Vec::new();
 
@@ -59,13 +71,16 @@ impl GitBare {
             if let Some((path_and_rest, matched)) = line.rsplit_once(':') {
                 let prefix_parts: Vec<&str> = path_and_rest.rsplitn(3, ':').collect();
                 if prefix_parts.len() >= 3
-                    && let Ok(line_num) = prefix_parts[0].parse::<u32>()
+                    && let Ok(line_num) = prefix_parts[1].parse::<u32>()
                 {
                     results.push(SearchResult {
                         path: prefix_parts[2].to_string(),
                         line: line_num,
                         matched_text: matched.to_string(),
                     });
+                    if results.len() >= max_results as usize {
+                        break;
+                    }
                 }
             }
         }
@@ -88,7 +103,7 @@ impl GitBare {
         let max_results = if request.max_results == 0 {
             100
         } else {
-            request.max_results
+            request.max_results.min(MAX_SEARCH_RESULTS)
         };
 
         let mut args = vec![
@@ -113,6 +128,12 @@ impl GitBare {
                 status_code: None,
                 stderr: e.to_string(),
             })?;
+        if !output.status.success() {
+            return Err(crate::error::GitError::CommandFailed {
+                status_code: output.status.code(),
+                stderr: String::from_utf8_lossy(&output.stderr).trim().to_string(),
+            });
+        }
 
         let stdout = String::from_utf8_lossy(&output.stdout);
         let mut results = Vec::new();