Store tokens on disk

Sources/App/TokenStorage.swift

@@ -0,0 +1,45 @@
+import Foundation
+import BinaryCodable
+
+struct TokenStorage {
+    
+    private(set) var tokens: Set<String>
+    
+    private let fileUrl: URL
+    
+    private let encoder = BinaryEncoder()
+    
+    init(in folder: URL) {
+        tokens = []
+        fileUrl = folder.appendingPathComponent("tokens")
+        
+        loadTokensFromDisk()
+    }
+    
+    private mutating func loadTokensFromDisk() {
+        guard FileManager.default.fileExists(atPath: fileUrl.path) else {
+            return
+        }
+        do {
+            let data = try Data(contentsOf: fileUrl)
+            tokens = try BinaryDecoder().decode(from: data)
+        } catch {
+            log(error: "Failed to read token file: \(error)")
+        }
+    }
+    
+    mutating func add(_ tokenUpload: TokenUpload) {
+        if let oldToken = tokenUpload.previousToken {
+            tokens.remove(oldToken.hex)
+        }
+        tokens.insert(tokenUpload.currentToken.hex)
+        do {
+            let data = try encoder.encode(tokens)
+            try data.write(to: fileUrl)
+        } catch {
+            log(error: "Failed to write token file: \(error)")
+        }
+    }
+    
+}
+

Sources/App/configure.swift

@@ -12,12 +12,16 @@ private let apnsEventGroup = MultiThreadedEventLoopGroup(numberOfThreads: System
 private let apnsRequestEncoder = JSONEncoder()
 private let apnsResponseDecoder = JSONDecoder()
 
+var tokenStorage: TokenStorage!
+
 // configures your application
 public func configure(_ app: Application) throws {
     
     let resourcesFolderUrl = URL(fileURLWithPath: app.directory.resourcesDirectory)
     let configUrl = resourcesFolderUrl.appendingPathComponent("config.json")
     
+    tokenStorage = .init(in: resourcesFolderUrl)
+    
     let config: ServerConfiguration
     do {
         let data = try Data(contentsOf: configUrl)
@@ -107,6 +111,10 @@ private func configureGPIO(_ config: ServerConfiguration) {
 }
 
 private func sendPush() {
+    guard !tokenStorage.tokens.isEmpty else {
+        log(info: "No tokens registered to send push")
+        return
+    }
     Task(priority: .userInitiated) {
         let client = APNSClient(
             configuration: apnsConfiguration,
@@ -115,7 +123,7 @@ private func sendPush() {
             requestEncoder: apnsRequestEncoder)
         log(info: "Client created")
         do {
-            for token in knownTokens {
+            for token in tokenStorage.tokens {
                 log(info: "Sending push to \(token.prefix(6))...")
                 try await client.sendAlertNotification(
                     apnsNotification,

Sources/App/routes.swift

@@ -6,8 +6,6 @@ private let requestDecoder = BinaryDecoder()
 
 var serverStatus: ServerStatus = .starting
 
-var knownTokens = Set<String>()
-
 func routes(_ app: Application) throws {
     
     app.post("token") { req async throws -> HTTPResponseStatus in
@@ -15,10 +13,7 @@ func routes(_ app: Application) throws {
             return .badRequest
         }
         let tokenUpload: TokenUpload = try requestDecoder.decode(from: data)
-        if let oldToken = tokenUpload.previousToken {
+        tokenStorage.add(tokenUpload)
-            knownTokens.remove(oldToken.hex)
-        }
-        knownTokens.insert(tokenUpload.currentToken.hex)
         return .ok
     }