feat(diagnostics): list and retrieve retained log files

crates/devolutions-log/src/lib.rs

@@ -21,6 +21,14 @@ pub trait StaticLogConfig {
     const LOG_FILE_PREFIX: &'static str;
 }
 
+/// Metadata for a retained log file in the configured log directory.
+pub struct LogFile {
+    pub path: std::path::PathBuf,
+    pub name: String,
+    pub size: u64,
+    pub modified: SystemTime,
+}
+
 pub struct LoggerGuard {
     _file_guard: WorkerGuard,
     _stdio_guard: WorkerGuard,
@@ -91,38 +99,90 @@ pub fn init<C: StaticLogConfig>(
     })
 }
 
-/// Find latest log file (by age)
+/// Finds the newest retained regular log file by modification time.
 ///
-/// Given path is used to filter out by file name prefix.
+/// Uses the same file filter and order as [`list_log_files`].
 #[instrument]
 pub async fn find_latest_log_file<C: StaticLogConfig>(prefix: &Utf8Path) -> anyhow::Result<std::path::PathBuf> {
-    let cfg = LogPathCfg::<C>::from_path(prefix)?;
+    list_log_files::<C>(prefix)
+        .await?
+        .into_iter()
+        .next()
+        .map(|file| file.path)
+        .context("no file found")
+}
+
+/// Lists the regular log files retained under the configured log path.
+pub async fn list_log_files<C: StaticLogConfig>(path: &Utf8Path) -> anyhow::Result<Vec<LogFile>> {
+    let cfg = LogPathCfg::<C>::from_path(path)?;
+    let mut read_dir = fs::read_dir(cfg.folder).await.context("couldn't read log directory")?;
+    let mut files = Vec::new();
 
-    let mut read_dir = fs::read_dir(cfg.folder).await.context("couldn't read directory")?;
+    while let Some(entry) = read_dir.next_entry().await.context("couldn't read log entry")? {
+        let Some(name) = entry.file_name().to_str().map(str::to_owned) else {
+            continue;
+        };
 
-    let mut most_recent_time = SystemTime::UNIX_EPOCH;
-    let mut most_recent = None;
+        if !name.starts_with(cfg.prefix) || !name.ends_with(".log") {
+            continue;
+        }
 
-    while let Ok(Some(entry)) = read_dir.next_entry().await {
-        match entry.file_name().to_str() {
-            Some(file_name) if file_name.starts_with(cfg.prefix) && file_name.contains("log") => {
-                debug!(file_name, "Found a log file");
-                match entry.metadata().await.and_then(|metadata| metadata.modified()) {
-                    Ok(modified) if modified > most_recent_time => {
-                        most_recent_time = modified;
-                        most_recent = Some(entry.path());
-                    }
-                    Ok(_) => {}
-                    Err(error) => {
-                        warn!(%error, file_name, "Couldn't retrieve metadata for file");
-                    }
-                }
+        let file_type = match entry.file_type().await {
+            Ok(file_type) => file_type,
+            Err(error) => {
+                warn!(%error, name, "Couldn't read log file type");
+                continue;
             }
-            _ => continue,
+        };
+        if !file_type.is_file() {
+            continue;
         }
+
+        let metadata = match entry.metadata().await {
+            Ok(metadata) => metadata,
+            Err(error) => {
+                warn!(%error, name, "Couldn't read log metadata");
+                continue;
+            }
+        };
+        let modified = match metadata.modified() {
+            Ok(modified) => modified,
+            Err(error) => {
+                warn!(%error, name, "Couldn't read log modification time");
+                continue;
+            }
+        };
+        files.push(LogFile {
+            path: entry.path(),
+            name,
+            size: metadata.len(),
+            modified,
+        });
+    }
+
+    files.sort_by(|left, right| {
+        right
+            .modified
+            .cmp(&left.modified)
+            .then_with(|| compare_log_file_names(&right.name, &left.name))
+    });
+    Ok(files)
+}
+
+fn compare_log_file_names(left: &str, right: &str) -> std::cmp::Ordering {
+    let rotations = left
+        .strip_suffix(".log")
+        .and_then(|name| name.rsplit_once('.'))
+        .zip(right.strip_suffix(".log").and_then(|name| name.rsplit_once('.')));
+
+    if let Some(((left_base, left_rotation), (right_base, right_rotation))) = rotations
+        && left_base == right_base
+        && let (Ok(left_rotation), Ok(right_rotation)) = (left_rotation.parse::<u64>(), right_rotation.parse::<u64>())
+    {
+        return left_rotation.cmp(&right_rotation).then_with(|| left.cmp(right));
     }
 
-    most_recent.context("no file found")
+    left.cmp(right)
 }
 
 /// File deletion task (by age)

devolutions-gateway/openapi/gateway-api.yaml

@@ -107,6 +107,63 @@ paths:
       security:
       - scope_token:
         - gateway.diagnostics.read
+  /jet/diagnostics/logs/files:
+    get:
+      tags:
+      - Diagnostics
+      summary: Lists the log files retained by this Gateway.
+      operationId: ListLogFiles
+      responses:
+        '200':
+          description: Retained log files
+          content:
+            application/json:
+              schema:
+                type: array
+                items:
+                  $ref: '#/components/schemas/LogFileInfo'
+        '401':
+          description: Invalid or missing authorization token
+        '403':
+          description: Insufficient permissions
+        '500':
+          description: Failed to list log files
+      security:
+      - scope_token:
+        - gateway.diagnostics.read
+  /jet/diagnostics/logs/files/{name}:
+    get:
+      tags:
+      - Diagnostics
+      summary: Retrieves one retained log file by its listed name.
+      operationId: GetLogFile
+      parameters:
+      - name: name
+        in: path
+        description: Name returned by ListLogFiles
+        required: true
+        schema:
+          type: string
+      responses:
+        '200':
+          description: Log file contents
+          content:
+            text/plain:
+              schema:
+                type: string
+        '400':
+          description: Invalid log file name
+        '401':
+          description: Invalid or missing authorization token
+        '403':
+          description: Insufficient permissions
+        '404':
+          description: Log file not found
+        '500':
+          description: Failed to read log file
+      security:
+      - scope_token:
+        - gateway.diagnostics.read
   /jet/health:
     get:
       tags:
@@ -2223,6 +2280,22 @@ components:
         internal_url:
           type: string
           description: URL to use on local network
+    LogFileInfo:
+      type: object
+      required:
+      - name
+      - size
+      - modifiedUnixMillis
+      properties:
+        modifiedUnixMillis:
+          type: integer
+          format: int64
+        name:
+          type: string
+        size:
+          type: integer
+          format: int64
+          minimum: 0
     MonitorDefinition:
       type: object
       required: