Allow log path specification

Sources/App/Management/Configuration.swift

@@ -33,6 +33,22 @@ struct Configuration {
 
     /// The authentication tokens to access the metrics
     let monitoringTokens: Set<String>
+    
+    /// The path to the folder where the metric logs are stored
+    ///
+    /// If no path is provided, then a folder `logs` in the resources directory is created
+    /// If the path is relative, then it is assumed relative to the resources directory
+    let logPath: String?
+    
+    func logURL(possiblyRelativeTo resourcesDirectory: URL) -> URL {
+        guard let logPath else {
+            return resourcesDirectory.appendingPathComponent("logs")
+        }
+        guard !logPath.hasPrefix("/") else {
+            return .init(fileURLWithPath: logPath)
+        }
+        return resourcesDirectory.appendingPathComponent(logPath)
+    }
 }
 
 extension Configuration {

Sources/App/configure.swift

@@ -30,7 +30,11 @@ public func configure(_ app: Application) throws {
 private func configureAsync(_ app: Application) async throws {
     let storageFolder = URL(fileURLWithPath: app.directory.resourcesDirectory)
     
-    let logFolder = storageFolder.appendingPathComponent("logs")
+    let configPath = URL(fileURLWithPath: app.directory.resourcesDirectory)
+        .appendingPathComponent("config.json")
+    let configuration = try Configuration(loadFromUrl: configPath)
+
+    let logFolder = configuration.logURL(possiblyRelativeTo: storageFolder)
     let monitor = MetricObserver(
         logFileFolder: logFolder,
         logMetricId: "schafkopf.log")
@@ -43,20 +47,6 @@ private func configureAsync(_ app: Application) async throws {
     
     _ = try? await status.update(.initializing)
 
-    let configPath = URL(fileURLWithPath: app.directory.resourcesDirectory)
-        .appendingPathComponent("config.json")
-    let configuration: Configuration
-
-    do {
-        configuration = try Configuration(loadFromUrl: configPath)
-    } catch {
-        _ = try? await status.update(.initializationFailure)
-        await monitor.log("Failed to read configuration: \(error)")
-        // Note: If configuration can't be loaded, then the server will run on the wrong port
-        // and access to metrics is impossible, since no tokens are loaded
-        return
-    }
-
     app.http.server.configuration.port = configuration.serverPort
 
     // Set target environment