Alerts: fetching and parsing.

dcd92a0e · Demid Merzlyakov · 3d8b7b8f · dcd92a0e · dcd92a0e · dcd92a0e
Commit dcd92a0e authored Apr 21, 2021 by Demid Merzlyakov
11 changed files
--- a/1Weather.xcodeproj/project.pbxproj
+++ b/1Weather.xcodeproj/project.pbxproj
@@ -13,6 +13,7 @@
 		87C1720D25FF870600DA3464 /* GeoNamesPlace.swift in Sources */ = {isa = PBXBuildFile; fileRef = 87C1720C25FF870600DA3464 /* GeoNamesPlace.swift */; };
 		87C1721025FF874B00DA3464 /* PartialLocation.swift in Sources */ = {isa = PBXBuildFile; fileRef = 87C1720F25FF874B00DA3464 /* PartialLocation.swift */; };
 		87C1724925FF94F400DA3464 /* ConfigManager.swift in Sources */ = {isa = PBXBuildFile; fileRef = 87C1724825FF94F400DA3464 /* ConfigManager.swift */; };
+		87D81582262EFC9B0015A6D1 /* Notifications.swift in Sources */ = {isa = PBXBuildFile; fileRef = 87D81581262EFC9A0015A6D1 /* Notifications.swift */; };
 		CD1237C3255D5C5900C98139 /* AppDelegate.swift in Sources */ = {isa = PBXBuildFile; fileRef = CD1237C2255D5C5900C98139 /* AppDelegate.swift */; };
 		CD1237CC255D5C5C00C98139 /* Assets.xcassets in Resources */ = {isa = PBXBuildFile; fileRef = CD1237CB255D5C5C00C98139 /* Assets.xcassets */; };
 		CD1237F1255D83C500C98139 /* UIColor+Hex.swift in Sources */ = {isa = PBXBuildFile; fileRef = CD1237F0255D83C500C98139 /* UIColor+Hex.swift */; };
@@ -117,6 +118,8 @@
 		CDF4808F261727E00076E9F5 /* CLAuthorizationStatus+Localized.swift in Sources */ = {isa = PBXBuildFile; fileRef = CDF4808E261727E00076E9F5 /* CLAuthorizationStatus+Localized.swift */; };
 		CDF48092261729680076E9F5 /* UIApplication+Settings.swift in Sources */ = {isa = PBXBuildFile; fileRef = CDF48091261729680076E9F5 /* UIApplication+Settings.swift */; };
 		CDF9BF8E26133D050037847D /* LocationSearchCoordinator.swift in Sources */ = {isa = PBXBuildFile; fileRef = CDF9BF8D26133D050037847D /* LocationSearchCoordinator.swift */; };
+		CE04561F26282325003D252B /* NWSCurrentEventsReponse.swift in Sources */ = {isa = PBXBuildFile; fileRef = CE04561E26282325003D252B /* NWSCurrentEventsReponse.swift */; };
+		CE0456242629C04C003D252B /* NWSAlertsManager.swift in Sources */ = {isa = PBXBuildFile; fileRef = CE0456232629C04C003D252B /* NWSAlertsManager.swift */; };
 		CE13B72826245CE2007CBD4D /* AirQuality.swift in Sources */ = {isa = PBXBuildFile; fileRef = CE13B72726245CE2007CBD4D /* AirQuality.swift */; };
 		CE13B72B26245D0D007CBD4D /* HealthStatus.swift in Sources */ = {isa = PBXBuildFile; fileRef = CE13B72A26245D0D007CBD4D /* HealthStatus.swift */; };
 		CE13B72E26245D42007CBD4D /* Pollutant.swift in Sources */ = {isa = PBXBuildFile; fileRef = CE13B72D26245D42007CBD4D /* Pollutant.swift */; };
@@ -151,6 +154,9 @@
 		CE13B88F26248A77007CBD4D /* GoogleService-Info-Staging.plist in Resources */ = {isa = PBXBuildFile; fileRef = CE13B88D26248A77007CBD4D /* GoogleService-Info-Staging.plist */; };
 		CE13B97B2626FB11007CBD4D /* PSMLocationSDK.xcframework in Frameworks */ = {isa = PBXBuildFile; fileRef = CE13B7DC262478E7007CBD4D /* PSMLocationSDK.xcframework */; };
 		CE13B97C2626FB11007CBD4D /* PSMLocationSDK.xcframework in Embed Frameworks */ = {isa = PBXBuildFile; fileRef = CE13B7DC262478E7007CBD4D /* PSMLocationSDK.xcframework */; settings = {ATTRIBUTES = (CodeSignOnCopy, RemoveHeadersOnCopy, ); }; };
+		CE13B98226272A1F007CBD4D /* AppNotification.swift in Sources */ = {isa = PBXBuildFile; fileRef = CE13B98126272A1F007CBD4D /* AppNotification.swift */; };
+		CE13B98526272E18007CBD4D /* WeatherAlert.swift in Sources */ = {isa = PBXBuildFile; fileRef = CE13B98426272E18007CBD4D /* WeatherAlert.swift */; };
+		CE13B98726273236007CBD4D /* NWSAlert.swift in Sources */ = {isa = PBXBuildFile; fileRef = CE13B98626273236007CBD4D /* NWSAlert.swift */; };
 		CE28474F26159857006C8DC5 /* HealthSource.swift in Sources */ = {isa = PBXBuildFile; fileRef = CE28474E26159857006C8DC5 /* HealthSource.swift */; };
 		CE28475226159A32006C8DC5 /* BlendHealthModels.swift in Sources */ = {isa = PBXBuildFile; fileRef = CE28475126159A32006C8DC5 /* BlendHealthModels.swift */; };
 		CE28475D2615A5B3006C8DC5 /* Health.swift in Sources */ = {isa = PBXBuildFile; fileRef = CE28475C2615A5B3006C8DC5 /* Health.swift */; };
@@ -237,6 +243,7 @@
 		87C1720C25FF870600DA3464 /* GeoNamesPlace.swift */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.swift; path = GeoNamesPlace.swift; sourceTree = "<group>"; };
 		87C1720F25FF874B00DA3464 /* PartialLocation.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = PartialLocation.swift; sourceTree = "<group>"; };
 		87C1724825FF94F400DA3464 /* ConfigManager.swift */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.swift; path = ConfigManager.swift; sourceTree = "<group>"; };
+		87D81581262EFC9A0015A6D1 /* Notifications.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = Notifications.swift; sourceTree = "<group>"; };
 		C8C576F6184B547435CFF0F3 /* Pods-1Weather.debug.xcconfig */ = {isa = PBXFileReference; includeInIndex = 1; lastKnownFileType = text.xcconfig; name = "Pods-1Weather.debug.xcconfig"; path = "Target Support Files/Pods-1Weather/Pods-1Weather.debug.xcconfig"; sourceTree = "<group>"; };
 		CD1237BF255D5C5900C98139 /* 1Weather.app */ = {isa = PBXFileReference; explicitFileType = wrapper.application; includeInIndex = 0; path = 1Weather.app; sourceTree = BUILT_PRODUCTS_DIR; };
 		CD1237C2255D5C5900C98139 /* AppDelegate.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = AppDelegate.swift; sourceTree = "<group>"; };
@@ -345,6 +352,8 @@
 		CDF4808E261727E00076E9F5 /* CLAuthorizationStatus+Localized.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = "CLAuthorizationStatus+Localized.swift"; sourceTree = "<group>"; };
 		CDF48091261729680076E9F5 /* UIApplication+Settings.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = "UIApplication+Settings.swift"; sourceTree = "<group>"; };
 		CDF9BF8D26133D050037847D /* LocationSearchCoordinator.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = LocationSearchCoordinator.swift; sourceTree = "<group>"; };
+		CE04561E26282325003D252B /* NWSCurrentEventsReponse.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = NWSCurrentEventsReponse.swift; sourceTree = "<group>"; };
+		CE0456232629C04C003D252B /* NWSAlertsManager.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = NWSAlertsManager.swift; sourceTree = "<group>"; };
 		CE13B72726245CE2007CBD4D /* AirQuality.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = AirQuality.swift; sourceTree = "<group>"; };
 		CE13B72A26245D0D007CBD4D /* HealthStatus.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = HealthStatus.swift; sourceTree = "<group>"; };
 		CE13B72D26245D42007CBD4D /* Pollutant.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = Pollutant.swift; sourceTree = "<group>"; };
@@ -379,6 +388,9 @@
 		CE13B809262480B3007CBD4D /* Scheduler.swift */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.swift; path = Scheduler.swift; sourceTree = "<group>"; };
 		CE13B88C26248A77007CBD4D /* GoogleService-Info-Production.plist */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = text.plist.xml; path = "GoogleService-Info-Production.plist"; sourceTree = "<group>"; };
 		CE13B88D26248A77007CBD4D /* GoogleService-Info-Staging.plist */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = text.plist.xml; path = "GoogleService-Info-Staging.plist"; sourceTree = "<group>"; };
+		CE13B98126272A1F007CBD4D /* AppNotification.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = AppNotification.swift; sourceTree = "<group>"; };
+		CE13B98426272E18007CBD4D /* WeatherAlert.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = WeatherAlert.swift; sourceTree = "<group>"; };
+		CE13B98626273236007CBD4D /* NWSAlert.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = NWSAlert.swift; sourceTree = "<group>"; };
 		CE28474E26159857006C8DC5 /* HealthSource.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = HealthSource.swift; sourceTree = "<group>"; };
 		CE28475126159A32006C8DC5 /* BlendHealthModels.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = BlendHealthModels.swift; sourceTree = "<group>"; };
 		CE28475C2615A5B3006C8DC5 /* Health.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = Health.swift; sourceTree = "<group>"; };
@@ -985,6 +997,34 @@
 			path = Firebase;
 			sourceTree = "<group>";
 		};
+		CE13B97D262725F0007CBD4D /* Notifications */ = {
+			isa = PBXGroup;
+			children = (
+				CE13B98026272A13007CBD4D /* Model */,
+				CE0456232629C04C003D252B /* NWSAlertsManager.swift */,
+			);
+			path = Notifications;
+			sourceTree = "<group>";
+		};
+		CE13B98026272A13007CBD4D /* Model */ = {
+			isa = PBXGroup;
+			children = (
+				CE13B98626273236007CBD4D /* NWSAlert.swift */,
+				CE04561E26282325003D252B /* NWSCurrentEventsReponse.swift */,
+			);
+			path = Model;
+			sourceTree = "<group>";
+		};
+		CE13B98326272A59007CBD4D /* Notifications */ = {
+			isa = PBXGroup;
+			children = (
+				CE13B98126272A1F007CBD4D /* AppNotification.swift */,
+				CE13B98426272E18007CBD4D /* WeatherAlert.swift */,
+				87D81581262EFC9A0015A6D1 /* Notifications.swift */,
+			);
+			path = Notifications;
+			sourceTree = "<group>";
+		};
 		CE28474C261597EB006C8DC5 /* Health */ = {
 			isa = PBXGroup;
 			children = (
@@ -1114,10 +1154,11 @@
 		CEAFF09925DFC78200DF4EBF /* Network */ = {
 			isa = PBXGroup;
 			children = (
-				CE28474C261597EB006C8DC5 /* Health */,
 				87C1724825FF94F400DA3464 /* ConfigManager.swift */,
 				87C171F325FF7A4000DA3464 /* PopularCitiesManager.swift */,
 				87C171F125FF7A3300DA3464 /* Weather */,
+				CE28474C261597EB006C8DC5 /* Health */,
+				CE13B97D262725F0007CBD4D /* Notifications */,
 			);
 			path = Network;
 			sourceTree = "<group>";
@@ -1141,6 +1182,7 @@
 				CEAFF08225DFC67F00DF4EBF /* Location.swift */,
 				CE28475726159B78006C8DC5 /* Weather */,
 				CE28475926159B85006C8DC5 /* Health */,
+				CE13B98326272A59007CBD4D /* Notifications */,
 			);
 			path = ModelObjects;
 			sourceTree = "<group>";
@@ -1531,6 +1573,7 @@
 				CD86246925E672A20097F3FB /* PrecipButton.swift in Sources */,
 				CD3F6E6C25FA5A90002DB99B /* PeriodButtonProtocol.swift in Sources */,
 				CEDE4E8225EEFD56007457E9 /* WdtWeatherCode.swift in Sources */,
+				CE04561F26282325003D252B /* NWSCurrentEventsReponse.swift in Sources */,
 				CD1DDD30260218AE00AC62B2 /* DaysControlView.swift in Sources */,
 				CE9D181625ECB8370028D9D7 /* MulticastDelegate.swift in Sources */,
 				CE578FE725FB415F00E8B85D /* LocationsViewModel.swift in Sources */,
@@ -1550,6 +1593,7 @@
 				CD593BD32608BC3F00C93428 /* ForecastDayCell.swift in Sources */,
 				CD4742D0261200500061AC95 /* TodayAlertCell.swift in Sources */,
 				CD15DB4225DA806C00024727 /* TodayForecastTimePeriodCell.swift in Sources */,
+				CE0456242629C04C003D252B /* NWSAlertsManager.swift in Sources */,
 				CE8962AB26175DF500CA274A /* CorePollutant.swift in Sources */,
 				CEC5276025E92DDA00DA58A5 /* WdtHourlySummary.swift in Sources */,
 				CDE18DCA25D165F100C80ED9 /* UITabBarController+Append.swift in Sources */,
@@ -1576,6 +1620,7 @@
 				CE9F01B8261B2DB6009BA500 /* _CoreAppData.swift in Sources */,
 				CDE18DCD25D1666700C80ED9 /* ForecastCoordinator.swift in Sources */,
 				CDC6126625E9085600188DA7 /* GraphLine.swift in Sources */,
+				CE13B98726273236007CBD4D /* NWSAlert.swift in Sources */,
 				CE13B819262480B3007CBD4D /* A9Cache.swift in Sources */,
 				CE578FE625FB415F00E8B85D /* LocationViewController.swift in Sources */,
 				CD86246525E66E8A0097F3FB /* PrecipitationCell.swift in Sources */,
@@ -1605,12 +1650,15 @@
 				CD32CE12260C77B400235081 /* MenuBuyButton.swift in Sources */,
 				CD86246C25E6826A0097F3FB /* InnerShadowLayer.swift in Sources */,
 				CE578FE525FB415F00E8B85D /* CityCell.swift in Sources */,
+				87D81582262EFC9B0015A6D1 /* Notifications.swift in Sources */,
 				CEAFF0A325E0FF0800DF4EBF /* LocationManager.swift in Sources */,
 				CE13B7E226247BF9007CBD4D /* UserDefaultsValue.swift in Sources */,
 				CEAD00A12577B2D5003596AD /* StuffThatIsPresentInTheMainProject.swift in Sources */,
+				CE13B98226272A1F007CBD4D /* AppNotification.swift in Sources */,
 				CEDE4E8925EEFFEF007457E9 /* WdtDayNight.swift in Sources */,
 				CE13B820262480B3007CBD4D /* AdLogger.swift in Sources */,
 				CDF48092261729680076E9F5 /* UIApplication+Settings.swift in Sources */,
+				CE13B98526272E18007CBD4D /* WeatherAlert.swift in Sources */,
 			);
 			runOnlyForDeploymentPostprocessing = 0;
 		};

--- a/1Weather/Model/LocationManager.swift
+++ b/1Weather/Model/LocationManager.swift
@@ -21,6 +21,7 @@ public class LocationManager {
    private let weatherUpdateSource: WeatherSource
    private let healthSource: HealthSource
+    private let nwsAlertsManager: NWSAlertsManager
    private let storage: Storage
    private var defaultLocation = Location(deviceLocation: false,
                                           coordinates: .init(latitude: 37.3230, longitude: -122.0322), // Cupertino
@@ -149,13 +150,14 @@ public class LocationManager {
        }
    }
-    public static let shared = LocationManager(weatherUpdateSource: WdtWeatherSource(), healthSource: BlendHealthSource(), storage: CoreDataStorage())
+    public static let shared = LocationManager(weatherUpdateSource: WdtWeatherSource(), healthSource: BlendHealthSource(), nwsAlertsManager: NWSAlertsManager(), storage: CoreDataStorage())
    public let maxLocationsCount = 12
-    public init(weatherUpdateSource: WeatherSource, healthSource: HealthSource, storage: Storage) {
+    public init(weatherUpdateSource: WeatherSource, healthSource: HealthSource, nwsAlertsManager: NWSAlertsManager, storage: Storage) {
        self.weatherUpdateSource = weatherUpdateSource
        self.healthSource = healthSource
        self.deviceLocationMonitor = DeviceLocationMonitor()
+        self.nwsAlertsManager = nwsAlertsManager
        self.storage = storage
        self.deviceLocationMonitor.delegate = self
@@ -181,6 +183,7 @@ public class LocationManager {
            log.info("Update all: update default location if needed.")
            updateWeather(for: defaultLocation, updateType: .full)
            updateHealth(for: defaultLocation)
+            updateNotifications(for: defaultLocation)
            return
        }
        log.info("Update all \(locations.count) locations if needed...")
@@ -192,6 +195,7 @@ public class LocationManager {
                updateWeather(for: location, updateType: .preferIncremental)
            }
            updateHealth(for: location)
+            updateNotifications(for: location)
        }
    }
@@ -229,6 +233,41 @@ public class LocationManager {
        }
    }
+    public func updateNotifications(for location: Location) {
+        if let lastTimeUpdated = location.notifications?.updatedAt {
+            guard Date().timeIntervalSince(lastTimeUpdated) >= nwsAlertsManager.updateInterval else {
+                log.info("Update notifications (\(location)): fresh enough (last updated at \(lastTimeUpdated), skip update")
+                return
+            }
+        }
+        log.info("Update notifications for \(location)")
+        nwsAlertsManager.fetchActiveAlerts(for: location) { [weak self] (alerts, error) in
+            guard let self = self else { return }
+            guard let alerts = alerts else {
+                if let error = error {
+                    self.log.error("Update notifications (\(location)) error: \(error)")
+                }
+                else {
+                    self.log.error("Update notifications (\(location)) error: unknown error")
+                }
+                return
+            }
+            let updatedNotifications = Notifications(updatedAt: Date(), nwsAlers: alerts)
+            self.log.info("Update notifications (\(location)): success.")
+            DispatchQueue.main.async {
+                if let indexToUpdate = self.locations.firstIndex(where: { $0 == location }) {
+                    self.locations[indexToUpdate].notifications = updatedNotifications
+                }
+                else if self.defaultLocation == location {
+                    self.defaultLocation.notifications = updatedNotifications
+                }
+                else {
+                    self.log.warning("Update notifications: Failed to find location after update. Maybe it was deleted while the update was performed. Maybe something went wrong. Location: \(location)")
+                }
+            }
+        }
+    }
    public func updateWeather(for location: Location?, updateType: WeatherUpdateType) {
        guard let location = location else {
            log.warning("Update weather: empty location.")

--- a/1Weather/Model/ModelObjects/Location.swift
+++ b/1Weather/Model/ModelObjects/Location.swift
@@ -15,6 +15,7 @@ public struct Location {
    public var lastWeatherUpdateDate: Date?
    public var coordinates: CLLocationCoordinate2D?
    public var imageName: String? = "ny_bridge" //we'll possibly need to switch to URL
+    public var notifications: Notifications?
    public var countryCode: String? {
        didSet {

--- a/1Weather/Model/ModelObjects/Notifications/AppNotification.swift
+++ b/1Weather/Model/ModelObjects/Notifications/AppNotification.swift
+//
+//  Notification.swift
+//  1Weather
+//
+//  Created by Demid Merzlyakov on 14.04.2021.
+//
+import Foundation
+protocol AppNotification {
+    var date: Date { get }
+    var title: String { get }
+    var text: String? { get }
+    var location: Location? { get }
+    var expires: Date? { get }
+    var expired: Bool { get }
+}
+extension AppNotification {
+    var expired: Bool {
+        guard let expires = expires else {
+            return false
+        }
+        return Date() < expires
+    }
+}
--- a/1Weather/Model/ModelObjects/Notifications/Notifications.swift
+++ b/1Weather/Model/ModelObjects/Notifications/Notifications.swift
+//
+//  Notifications.swift
+//  1Weather
+//
+//  Created by Demid Merzlyakov on 20.04.2021.
+//
+import Foundation
+public struct Notifications {
+    public let updatedAt: Date
+    public let nwsAlers: [NWSAlert]
+}
--- a/1Weather/Model/ModelObjects/Notifications/WeatherAlert.swift
+++ b/1Weather/Model/ModelObjects/Notifications/WeatherAlert.swift
+//
+//  NWSAlert.swift
+//  1Weather
+//
+//  Created by Demid Merzlyakov on 14.04.2021.
+//
+import Foundation
+struct WeatherAlert: AppNotification {
+    var date: Date
+    var title: String
+    var text: String?
+    var location: Location?
+    var expires: Date?
+    var whatText: String?
+    var whereText: String?
+    var whenText: String?
+    var impactText: String?
+    var instructionsText: String?
+    var targetAreaText: String?
+}
--- a/1Weather/Network/Health/BlendHealthSource.swift
+++ b/1Weather/Network/Health/BlendHealthSource.swift
@@ -29,9 +29,9 @@ public class BlendHealthSource: HealthSource {
    private static let blendAPIKeyHeaderName = "blend-api-key"
    private static let blendAPIKey = "0imfnc8mVLWwsAawjYr4Rx-Af50DDqtlx"
    #if DEBUG
-    public var healthUpdateInterval: TimeInterval = TimeInterval(2 * 60) // 2 minutes
+    public let healthUpdateInterval = TimeInterval(2 * 60) // 2 minutes
    #else
-    public var healthUpdateInterval: TimeInterval = TimeInterval(15 * 60) // 15 minutes
+    public let healthUpdateInterval = TimeInterval(15 * 60) // 15 minutes
    #endif
    /// This queue is needed to synchronize access to locationsBeingUpdated. Also, to make logging more clear.
    private let internalQueue: OperationQueue = {

--- a/1Weather/Network/Notifications/Model/NWSAlert.swift
+++ b/1Weather/Network/Notifications/Model/NWSAlert.swift
+//
+//  NWSAlert.swift
+//  1Weather
+//
+//  Created by Demid Merzlyakov on 14.04.2021.
+//
+import Foundation
+public enum NWSSeverityLevel: String, Codable {
+    case warning = "1"
+    case watch = "2"
+    case advisory = "3"
+}
+public struct NWSAlert: Codable, Equatable, Hashable {
+    public let weatherID: String
+    public let messageID: String
+    public let messageURL: String
+    public let severityLevel: NWSSeverityLevel
+    public let description: String
+    public let expires: Date //expiresUTC="2012-09-25 01:00:00"
+    /// This is the contents of the messageURL. Fetched separately.
+    public var weatherMessage: String? = nil
+    /// This property is set by NWSAlertManager after decoding the response.
+    public var city: String = ""
+    // Used to encode/decode a JSON object to send/recieve data with the server
+    private enum CodingKeys: String, CodingKey {
+        case weatherID
+        case messageID
+        case severityLevel
+        case description
+        case expires = "expiresUTC"
+        case messageURL
+    }
+    public var expired: Bool {
+        return Date() < expires
+    }
+    // MARK: Equatable implementation
+    public static func == (lhs: Self, rhs: Self) -> Bool {
+        return lhs.weatherID == rhs.weatherID &&
+        lhs.messageID == rhs.messageID &&
+        lhs.messageURL == rhs.messageURL &&
+        lhs.severityLevel == rhs.severityLevel &&
+        lhs.description == rhs.description &&
+        lhs.expires == rhs.expires
+        // do not compare weatherMessage & city
+    }
+    public func hash(into hasher: inout Hasher) {
+        hasher.combine(weatherID)
+        hasher.combine(messageID)
+        hasher.combine(messageURL)
+        hasher.combine(severityLevel)
+        hasher.combine(description)
+        hasher.combine(expires)
+    }
+}
--- a/1Weather/Network/Notifications/Model/NWSCurrentEventsReponse.swift
+++ b/1Weather/Network/Notifications/Model/NWSCurrentEventsReponse.swift
+//
+//  NWSCurrentEventsReponse.swift
+//  1Weather
+//
+//  Created by Demid Merzlyakov on 15.04.2021.
+//
+import Foundation
+struct NWSCurrentEventsReponse: Codable {
+    struct Wrapper: Codable {
+        let events: [NWSAlert]?
+    }
+    let status: String
+    let events: NWSCurrentEventsReponse.Wrapper?
+}
--- a/1Weather/Network/Notifications/NWSAlertsManager.swift
+++ b/1Weather/Network/Notifications/NWSAlertsManager.swift
+//
+//  NWSAlertsManager.swift
+//  1Weather
+//
+//  Created by Demid Merzlyakov on 16.04.2021.
+//
+import Foundation
+public enum NWSError: Error {
+    case insufficientLocationInfo
+    case alreadyBeingUpdated
+    case badUrl
+    case networkError(Error?)
+    case badServerResponse(Error?)
+}
+public class NWSAlertsManager {
+    public typealias Completion = ([NWSAlert]?, NWSError?) -> ()
+    #if DEBUG
+    public let updateInterval = TimeInterval(2 * 60) // 2 minutes
+    #else
+    public let updateInterval = TimeInterval(15 * 60) // 15 minutes
+    #endif
+    #if DEBUG
+    public var useStaging = true
+    #else
+    public var useStaging = false
+    #endif
+    private let baseUrlProduction = "https://nwsalert.onelouder.com"
+    private let baseUrlStaging = "https://sta-nwsalert.onelouder.com"
+    private let log = Logger(componentName: "NWSAlertsManager")
+    private var locationsBeingUpdated = Set<Location>()
+    private var baseUrl: String {
+        useStaging ? baseUrlStaging : baseUrlProduction
+    }
+    /// This queue is needed to synchronize access to locationsBeingUpdated and the alerts list. Also, to make logging more clear.
+    private let internalQueue: OperationQueue = {
+        let queue = OperationQueue()
+        queue.name = "WdtWeatherSource Queue"
+        queue.maxConcurrentOperationCount = 1
+        return queue
+    }()
+    private lazy var currentEventsDateFormatter: DateFormatter = {
+        let dateFormatter = DateFormatter()
+        dateFormatter.dateFormat = "yyyy-MM-dd HH:mm:ss"
+        dateFormatter.timeZone = TimeZone(secondsFromGMT: 0)
+        return dateFormatter
+    }()
+    public var alerts = [NWSAlert]()
+    public func fetchActiveAlerts(for location: Location, completion: @escaping NWSAlertsManager.Completion) {
+        internalQueue.addOperation { [weak self] in
+            let extendedCompletion: NWSAlertsManager.Completion = { [weak self] (updatedLocation, error) in
+                self?.internalQueue.addOperation {
+                    completion(updatedLocation, error)
+                    self?.locationsBeingUpdated.remove(location)
+                }
+            }
+            self?.fetchActiveAlertsInternal(for: location, completion: extendedCompletion)
+        }
+    }
+    private func fetchActiveAlertsInternal(for location: Location, completion: @escaping NWSAlertsManager.Completion) {
+        guard !locationsBeingUpdated.contains(location) else {
+            completion(nil, .alreadyBeingUpdated)
+            return
+        }
+        locationsBeingUpdated.insert(location)
+        log.info("Start update for \(location)")
+        var params: [String: String] = [
+            "format": "json"
+        ]
+        if let fips_code = location.fipsCode {
+            params["weather_id"] = fips_code
+        }
+        else if let coordinates = location.coordinates{
+            params["geo"] = String(format: "%.5f,%.5f", coordinates.latitude, coordinates.longitude)
+        }
+        else {
+            completion(nil, .insufficientLocationInfo)
+            return
+        }
+        params["echoCity"] = location.cityName
+        guard var urlComponents = URLComponents(string: self.baseUrl.appending("/current_events")) else {
+            log.error("Couldn't create URLComponents from \(self.baseUrl)")
+            completion(nil, .badUrl)
+            fatalError("Should never happen. Couldn't create URL components from \(self.baseUrl). This URL has to always be correct.") // Should never happen, but a lot of stuff that should never happen happens from time to time, so let's at least handle it gracefully in prod.
+            return
+        }
+        urlComponents.queryItems = params.map { URLQueryItem(name: $0, value: $1) }
+        guard let url = urlComponents.url else {
+            log.error("Couldn't create URL with params: \(params)")
+            completion(nil, .badUrl)
+            return
+        }
+        let urlSession = URLSession.shared
+        let dataTask = urlSession.dataTask(with: url) { [weak self] (data, response, error) in
+            guard let self = self else { return }
+            guard let data = data else {
+                completion(nil, .networkError(error))
+                return
+            }
+            let decoder = JSONDecoder()
+            decoder.dateDecodingStrategy = .formatted(self.currentEventsDateFormatter)
+            do {
+                let response = try decoder.decode(NWSCurrentEventsReponse.self, from: data)
+                guard let events = response.events?.events else {
+                    completion(nil, .badServerResponse(nil))
+                    return
+                }
+                let eventsWithLocation: [NWSAlert] = events.map { (alert) -> NWSAlert in
+                    var updated: NWSAlert = alert
+                    updated.city = location.cityName ?? ""
+                    return updated
+                }
+                self.merge(alerts: eventsWithLocation)
+                completion(eventsWithLocation, nil)
+            }
+            catch {
+                completion(nil, .badServerResponse(error))
+            }
+        }
+        dataTask.resume()
+    }
+    func merge(alerts newAlerts: [NWSAlert]) {
+        //TODO: optimize
+        var resultingSet = Set<NWSAlert>()
+        for alert in self.alerts {
+            if !alert.expired {
+                resultingSet.insert(alert)
+            }
+        }
+        for alert in newAlerts {
+            if !alert.expired {
+                resultingSet.insert(alert)
+            }
+        }
+        // TODO: maybe we need a more sophisticated logic for sorting: take severity into account, for instance.
+        let resultingAlerts = resultingSet.sorted(by: { $1.expires > $0.expires })
+        // sync, because we don't want another merge to strat before assignment to self.alerts completes.
+        // A deadlock shouldn't happen unless main thread waits on internalQueue, which it doesn't.
+        DispatchQueue.main.sync {
+            self.alerts = resultingAlerts
+        }
+    }
+}
--- a/1Weather/Network/Weather/WdtWeatherSource.swift
+++ b/1Weather/Network/Weather/WdtWeatherSource.swift
@@ -68,7 +68,10 @@ public class WdtWeatherSource: WeatherSource {
        }
        guard var urlComponents = URLComponents(string: urlToUse) else {
+            log.error("Couldn't create URLComponents from \(urlToUse)")
            assertionFailure("Should never happen. The URL should be correct.")
+            // Should never happen, but a lot of stuff that should never happen happens from time to time, so let's at least handle it gracefully in prod.
+            completion(nil, WdtWeatherSourceError.badUrl)
            return
        }
@@ -93,6 +96,7 @@ public class WdtWeatherSource: WeatherSource {
        urlComponents.queryItems = queryParameters.map { URLQueryItem(name: $0, value: $1) }
        guard let url = urlComponents.url else {
+            log.error("Couldn't create URL with params: \(queryParameters)")
            completion(nil, WdtWeatherSourceError.badUrl)
            return
        }