32.2 Recording from the application

db.CustomLogs is the store's ICustomLogs. There are four ways to record, each one entry per call:

// property-value pairs, timestamped now
db.CustomLogs.Record("requests",
    ("path", ctx.Request.Path.Value), ("status", 200), ("duration", sw.Elapsed.TotalMilliseconds));

// an object: its public properties are matched to the columns, ignoring case
db.CustomLogs.RecordObject("requests",
    new { Path = "/products", Status = 200, Duration = 12.5, Position = new GeoCoordinate(59.9139, 10.7522) });

// a dictionary, with a time of its own
db.CustomLogs.Record("requests", new Dictionary<string, object?> { ["path"] = "/cart" }, timestampUtc: startedUtc);

// an entry, when the timestamp and the values are built elsewhere
db.CustomLogs.Record("requests", new LogEntry { Timestamp = startedUtc, Values = { ["status"] = 404 } });

Recording is cheap. A log that does not exist or is switched off costs a dictionary lookup, and Record returns false when no log has the key. Entries are buffered and written to disk every 30 seconds, or sooner when a megabyte is waiting. Record(key, entry, flushToDisk: true) writes one entry at once, and db.CustomLogs.FlushToDiskNow() writes everything waiting.

Values are converted to their column's type when you record them:

Column type	What converts into it
Text	Anything. Numbers and dates are written the same on every server (`1.5`, ISO 8601 in UTC), bytes as base64
Whole number	Integer types (a `long` is clamped to the `int` range), enums, `bool` as 1/0, rounded `double` and `decimal`, numeric text
Decimal number	Any number, `bool`, `TimeSpan` as milliseconds, numeric text; not `NaN` or infinity
Date and time	`DateTime` (stored in UTC; an unspecified kind counts as UTC), `DateTimeOffset`, `DateOnly`, ISO text
Duration	`TimeSpan`, `TimeOnly`, a number of milliseconds, text such as `00:01:30`
Bytes	`byte[]`, `Memory<byte>`, `ArraySegment<byte>`, text as UTF-8
Position	`GeoCoordinate`, text such as `59.91, 10.75`, a `(latitude, longitude)` tuple or a two-element array (§32.8)

A value that is null, or does not convert, is left out of the entry rather than recorded as a zero the statistics would count. Values under keys the log does not declare are kept as they are, so a column added later can read them. Timestamps are stored in UTC.