Support environment based log config in the demo app (#1062)

Author: laevandus

DemoAppSwiftUI/AppDelegate.swift

@@ -61,6 +61,14 @@ class AppDelegate: NSObject, UIApplicationDelegate {
         }
         #endif
 
+        LogConfig.level = StreamRuntimeCheck.logLevel ?? .warning
+        LogConfig.formatters = [
+            PrefixLogFormatter(prefixes: [.info: "ℹ️", .debug: "🛠", .warning: "⚠️", .error: "🚨"])
+        ]
+        if let subsystems = StreamRuntimeCheck.subsystems {
+            LogConfig.subsystems = subsystems
+        }
+        
         let utils = Utils(
             channelListConfig: ChannelListConfig(
                 messageRelativeDateFormatEnabled: true,
@@ -142,3 +150,17 @@ class AppDelegate: NSObject, UIApplicationDelegate {
 extension UIColor {
     static let streamBlue = UIColor(red: 0, green: 108.0 / 255.0, blue: 255.0 / 255.0, alpha: 1)
 }
+
+extension StreamRuntimeCheck {
+    static var logLevel: LogLevel? {
+        guard let value = ProcessInfo.processInfo.environment["STREAM_LOG_LEVEL"] else { return nil }
+        guard let intValue = Int(value) else { return nil }
+        return LogLevel(rawValue: intValue)
+    }
+    
+    static var subsystems: LogSubsystem? {
+        guard let value = ProcessInfo.processInfo.environment["STREAM_LOG_SUBSYSTEM"] else { return nil }
+        guard let intValue = Int(value) else { return nil }
+        return LogSubsystem(rawValue: intValue)
+    }
+}

DemoAppSwiftUI/LoginViewModel.swift

@@ -25,7 +25,6 @@ class LoginViewModel: ObservableObject {
     private func connectUser(withCredentials credentials: UserCredentials) {
         loading = true
         let token = try! Token(rawValue: credentials.token)
-        LogConfig.level = .warning
 
         chatClient.connectUser(
             userInfo: .init(
@@ -53,7 +52,6 @@ class LoginViewModel: ObservableObject {
 
     private func connectGuestUser(withCredentials credentials: UserCredentials) {
         loading = true
-        LogConfig.level = .warning
 
         chatClient.connectGuestUser(
             userInfo: .init(id: credentials.id, name: credentials.name)