Write log header later to ensure game identifiers are present

[peppy]

The flow in GameHost ensures that the game/version identifiers are set before Logger.Storage is set. Unfortunately, until now any call to the static Logger.Log would immediately materialise the headers into their final string form. A stray log call before GameHost.Run could result in less-than-optimal headers.

This can be seen in osu!'s runtime log from an early log call.

Before:

2024-01-17 15:34:40 [verbose]: ----------------------------------------------------------
2024-01-17 15:34:40 [verbose]: runtime Log for dean (LogLevel: Debug)
2024-01-17 15:34:40 [verbose]: Running game unknown on .NET 6.0.25
2024-01-17 15:34:40 [verbose]: Environment: macOS (Unix 14.3.0), 8 cores
2024-01-17 15:34:40 [verbose]: ----------------------------------------------------------
2024-01-17 15:34:40 [verbose]: Starting legacy IPC provider...

After:

----------------------------------------------------------
runtime Log for dean (LogLevel: Debug)
Running osu-development 0.0.0.0 on .NET 6.0.25
Environment: macOS (Unix 14.3.0), 8 cores 
----------------------------------------------------------
2024-01-17 15:27:24 [verbose]: Starting legacy IPC provider...

Note that timestamps are not prefixed to the header now, but I think this is probably for the best.

[bdach]

Note that timestamps are not prefixed to the header now, but I think this is probably for the best.

Is there any particular reason for that? Not that I necessarily care very much, but it just reads like a non-sequitur compared to the rest of the OP. I don't see why that measure would need to be taken.

[peppy]

I don't see why that measure would need to be taken.

I can add it back, but if you check the code it should be apparently why they aren't there (different code path now).

It would look something like this:

diff --git a/osu.Framework/Logging/Logger.cs b/osu.Framework/Logging/Logger.cs
index 32731b801..63dddb504 100644
--- a/osu.Framework/Logging/Logger.cs
+++ b/osu.Framework/Logging/Logger.cs
@@ -315,7 +315,7 @@ private void add(string message = @"", LogLevel level = LogLevel.Verbose, Except
             IEnumerable<string> lines = logOutput
                                         .Replace(@"\r\n", @"\n")
                                         .Split('\n')
-                                        .Select(s => $@"{DateTime.UtcNow.ToString("yyyy-MM-dd HH:mm:ss", CultureInfo.InvariantCulture)} [{level.ToString().ToLowerInvariant()}]: {s.Trim()}");
+                                        .Select(l => addTimestamp(l, level));
 
             if (outputToListeners)
             {
@@ -394,11 +394,16 @@ private void writePendingLines()
                 {
                     if (!headerAdded)
                     {
-                        writer.WriteLine("----------------------------------------------------------");
-                        writer.WriteLine($"{Name} Log for {UserIdentifier} (LogLevel: {Level})");
-                        writer.WriteLine($"Running {GameIdentifier} {VersionIdentifier} on .NET {Environment.Version}");
-                        writer.WriteLine($"Environment: {RuntimeInfo.OS} ({Environment.OSVersion}), {Environment.ProcessorCount} cores ");
-                        writer.WriteLine("----------------------------------------------------------");
+                        lines = new[]
+                                {
+                                    "----------------------------------------------------------",
+                                    $"{Name} Log for {UserIdentifier} (LogLevel: {Level})",
+                                    $"Running {GameIdentifier} {VersionIdentifier} on .NET {Environment.Version}",
+                                    $"Environment: {RuntimeInfo.OS} ({Environment.OSVersion}), {Environment.ProcessorCount} cores ",
+                                    "----------------------------------------------------------"
+                                }
+                                .Select(l => addTimestamp(l, Level))
+                                .Concat(lines).ToArray();
 
                         headerAdded = true;
                     }
@@ -412,6 +417,11 @@ private void writePendingLines()
             }
         }
 
+        private string addTimestamp(string s, LogLevel level)
+        {
+            return $@"{DateTime.UtcNow.ToString("yyyy-MM-dd HH:mm:ss", CultureInfo.InvariantCulture)} [{level.ToString().ToLowerInvariant()}]: {s.Trim()}";
+        }
+
         /// <summary>
         /// Whether the output of this logger should be sent to listeners of <see cref="Debug"/> and <see cref="Console"/>.
         /// Defaults to true.

[bdach]

seems fine