public LogMessageProperties(LogMessageTemplate template, object[] values)
{
_template = template;
_values = values;
Count = values.Length;
}
/// <summary>
/// Logs a message and/or exception with the specified <see cref="LogLevel"/>, <see cref="LogEventId"/>
/// and properties.
/// </summary>
/// <param name="logger">The <see cref="ILogger"/>.</param>
/// <param name="level">The <see cref="LogLevel"/>.</param>
/// <param name="id">The unique identifier of the log event.</param>
/// <param name="exception">The <see cref="Exception"/> that occured, may be <c>null</c>.</param>
/// <param name="format">The format of the log message.</param>
/// <param name="args">The format arguments used to format the message.</param>
public static void Log(
this ILogger logger,
LogLevel level,
LogEventId id,
Exception exception,
string format,
params object[] args)
{
Ensure.Arg.NotNull(logger, nameof(logger));
if (logger.IsEnabled(level))
{
LogMessageTemplate template = LogMessageTemplateCache.Get(format);
if (template.VariableNames.Count != args?.Length)
{
throw new ArgumentException(
"Number of arguments does not match the number of format variables.",
nameof(args));
}
IReadOnlyList <LogProperty> properties = args?.Length == 0
? LogMessageProperties.Empty
: new LogMessageProperties(template, args);
Log(logger, level, id, exception, template, properties);
}
}
/// <summary>
/// Defines a delegate which writes log event without any properties.
/// </summary>
/// <param name="level">The <see cref="LogLevel"/>.</param>
/// <param name="id">The <see cref="LogEventId"/> which uniquely identifies the event.</param>
/// <param name="format">The log message format.</param>
/// <returns>The delegate which must be invoked to write the log event.</returns>
/// <exception cref="ArgumentNullException">Argument <paramref name="format"/> is <c>null</c>.</exception>
public static LoggerEventDelegate Define(LogLevel level, LogEventId id, string format)
{
LogMessageTemplate template = CreateTemplate(format, 0);
return((logger, exception, properties) =>
{
if (logger.IsEnabled(level))
{
logger.Log(level, id, exception, template, properties);
}
});
}
// ReSharper disable once ParameterOnlyUsedForPreconditionCheck.Local
private static LogMessageTemplate CreateTemplate(string format, int expectedParameterCount)
{
Ensure.Arg.NotNull(format, nameof(format));
var template = new LogMessageTemplate(format);
if (template.VariableNames.Count < expectedParameterCount)
{
throw new ArgumentException("Number of format variables is less than the number of arguments.",
nameof(format));
}
return(template);
}
/// <summary>
/// Initializes a new instance of the <see cref="LogEvent"/> struct.
/// </summary>
/// <param name="timestamp">The timestamp of the event.</param>
/// <param name="level">The log level of the event</param>
/// <param name="id">The unique identifier of the event</param>
/// <param name="messageTemplate">The <see cref="LogMessageTemplate"/> used to render the event.</param>
/// <param name="properties">The properties that are logged.</param>
/// <param name="exception">The <see cref="System.Exception"/> that will be logged.</param>
public LogEvent(
DateTimeOffset timestamp,
LogLevel level,
LogEventId id,
LogMessageTemplate messageTemplate,
IReadOnlyList <LogProperty> properties = null,
Exception exception = null
)
{
Timestamp = timestamp;
Level = level;
Id = id;
MessageTemplate = messageTemplate ?? LogMessageTemplate.Empty;
Properties = properties ?? LogMessageProperties.Empty;
Exception = exception;
}
/// <summary>
/// Defines a delegate which writes log event with two properties.
/// </summary>
/// <param name="level">The <see cref="LogLevel"/>.</param>
/// <param name="id">The <see cref="LogEventId"/> which uniquely identifies the event.</param>
/// <param name="format">The log message format.</param>
/// <returns>The delegate which must be invoked to write the log event.</returns>
/// <exception cref="ArgumentNullException">Argument <paramref name="format"/> is <c>null</c>.</exception>
/// <exception cref="ArgumentException">Number of format variables is less than the number of arguments.</exception>
public static LoggerEventDelegate <T0, T1> Define <T0, T1>(LogLevel level, LogEventId id, string format)
{
LogMessageTemplate template = CreateTemplate(format, 2);
return((logger, arg0, arg1, exception, properties) =>
{
if (logger.IsEnabled(level))
{
logger.Log(
level,
id,
exception,
template,
new LogMessageProperties <T0, T1>(template, arg0, arg1, properties));
}
});
}
internal static void Log(
this ILogger logger,
LogLevel level,
LogEventId id,
Exception exception,
LogMessageTemplate messageTemplate,
IReadOnlyList <LogProperty> properties)
{
logger.Log(
new LogEvent(
GetTimestamp(),
level,
id,
messageTemplate,
properties,
exception));
}
public void Ignores_VariableNames_In_DoubleCurlyBraces()
{
var template = new LogMessageTemplate("abc {value1} defg {{value2}}");
Assert.Equal(new[] { "value1" }, template.VariableNames);
}
public void Parses_VariablesNames_From_CurlyBraces()
{
var template = new LogMessageTemplate("abc {value1} defg {value2}");
Assert.Equal(new[] { "value1", "value2" }, template.VariableNames);
}
