Update metrics logging

Package.swift

@@ -8,7 +8,7 @@ let package = Package(
     ],
     dependencies: [
         .package(url: "https://github.com/vapor/vapor", from: "4.0.0"),
-        .package(url: "https://github.com/christophhagen/Clairvoyant", from: "0.4.0"),
+        .package(url: "https://github.com/christophhagen/Clairvoyant", from: "0.5.0"),
     ],
     targets: [
         .target(name: "App",

Sources/App/CapServer.swift

@@ -41,7 +41,9 @@ final class CapServer {
     var classifierVersion: Int = 0 {
         didSet {
             writeClassifierVersion()
-            classifierMetric.update(classifierVersion)
+            Task {
+                try? await classifierMetric.update(classifierVersion)
+            }
         }
     }
 
@@ -62,8 +64,10 @@ final class CapServer {
     private var caps = [Int: Cap]() {
         didSet {
             scheduleSave()
-            capCountMetric.update(caps.count)
+            Task {
-            imageCountMetric.update(imageCount)
+                try? await capCountMetric.update(caps.count)
+                try? await imageCountMetric.update(imageCount)
+            }
         }
     }
 
@@ -79,7 +83,7 @@ final class CapServer {
         caps.reduce(0) { $0 + $1.value.count }
     }
 
-    init(in folder: URL) {
+    init(in folder: URL) async {
         self.imageFolder = folder.appendingPathComponent("images")
         self.thumbnailFolder = folder.appendingPathComponent("thumbnails")
         self.gridCountFile = folder.appendingPathComponent("count.js")
@@ -90,6 +94,19 @@ final class CapServer {
         self.changedImagesFile = folder.appendingPathComponent("changes.txt")
         self.changedImageEntryDateFormatter = DateFormatter()
         changedImageEntryDateFormatter.dateFormat = "yy-MM-dd-HH-mm-ss"
+
+        // Metric initializers only fail if observer is missing or ID is duplicate
+        self.capCountMetric = try! await .init("caps.count",
+                                    name: "Number of caps",
+                                    description: "The total number of caps in the database")
+
+        self.imageCountMetric = try! await .init("caps.images",
+                                      name: "Total images",
+                                      description: "The total number of images for all caps")
+
+        self.classifierMetric = try! await .init("caps.classifier",
+                                      name: "Classifier Version",
+                                      description: "The current version of the image classifier")
     }
 
     func loadData() throws {
@@ -460,15 +477,9 @@ final class CapServer {
 
     // MARK: Monitoring
 
-    private let capCountMetric = Metric<Int>("caps.count",
+    private let capCountMetric: Metric<Int>
-                                             name: "Number of caps",
-                                             description: "The total number of caps in the database")
 
-    private let imageCountMetric = Metric<Int>("caps.images",
+    private let imageCountMetric: Metric<Int>
-                                               name: "Total images",
-                                               description: "The total number of images for all caps")
 
-    private let classifierMetric = Metric<Int>("caps.classifier",
+    private let classifierMetric: Metric<Int>
-                                               name: "Classifier Version",
-                                               description: "The current version of the image classifier")
 }

Sources/App/configure.swift

@@ -2,7 +2,7 @@ import Vapor
 import Foundation
 import Clairvoyant
 
-public func configure(_ app: Application) throws {
+public func configure(_ app: Application) async throws {
 
     let resourceDirectory = URL(fileURLWithPath: app.directory.resourcesDirectory)
     let publicDirectory = app.directory.publicDirectory
@@ -10,7 +10,7 @@ public func configure(_ app: Application) throws {
     let config = Config(loadFrom: resourceDirectory)
     let authenticator = Authenticator(writers: config.writers)
 
-    let monitor =  MetricObserver(
+    let monitor = await MetricObserver(
         logFolder: config.logURL,
         accessManager: authenticator,
         logMetricId: "caps.log")
@@ -18,18 +18,18 @@ public func configure(_ app: Application) throws {
     // All new metrics are automatically registered with the standard observer
     MetricObserver.standard = monitor
 
-    let status = Metric<ServerStatus>("caps.status",
+    let status = try await Metric<ServerStatus>("caps.status",
                                       name: "Status",
                                       description: "The general status of the service")
-    status.update(.initializing)
+    try await status.update(.initializing)
-
-    let server = CapServer(in: URL(fileURLWithPath: publicDirectory))
-
-    monitor.registerRoutes(app)
 
     app.http.server.configuration.port = config.port
     app.routes.defaultMaxBodySize = .init(stringLiteral: config.maxBodySize)
 
+    let server = await CapServer(in: URL(fileURLWithPath: publicDirectory))
+
+    await monitor.registerRoutes(app)
+
     if config.serveFiles {
         let middleware = FileMiddleware(publicDirectory: publicDirectory)
         app.middleware.use(middleware)
@@ -41,13 +41,18 @@ public func configure(_ app: Application) throws {
     // Initialize the server data
     do {
         try server.loadData()
-        status.update(.nominal)
     } catch {
-        status.update(.initializationFailure)
+        try await status.update(.initializationFailure)
     }
+    try await status.update(.nominal)
 }
 
 func log(_ message: String) {
-    MetricObserver.standard?.log(message)
+    guard let observer = MetricObserver.standard else {
-    print(message)
+        print(message)
+        return
+    }
+    Task {
+        await observer.log(message)
+    }
 }

Sources/Run/main.swift

@@ -5,5 +5,11 @@ var env = Environment.production
 try LoggingSystem.bootstrap(from: &env)
 let app = Application(env)
 defer { app.shutdown() }
-try configure(app)
+
+private let semaphore = DispatchSemaphore(value: 1)
+Task {
+    try await configure(app)
+    semaphore.signal()
+}
+semaphore.wait()
 try app.run()