Interaction with other Vostok libraries

The main value of Vostok.Logging – integration with other Vostok's libraries.

Logging + Context

Logging.Context lets you say, " Let's automatically add properties from context to this log." If you use ContextualLogPrefix, you can do so:

var log = new ConsoleLog().WithContextualPrefix();

using (new ContextualLogPrefix("op-1"))
{
    log.Info("Message 1!");
    
    using (new ContextualLogPrefix("op-2"))
    {
        log.Info("Message 2!");
    }               
    
    log.Info("Message 3!");
}
ConsoleLog.Flush();

Result:

2018-12-11 16:06:37,970 INFO  [op-1] Message 1!
2018-12-11 16:06:38,047 INFO  [op-1] [op-2] Message 2!
2018-12-11 16:06:38,047 INFO  [op-1] Message 3!

Logging + Hercules

Logging.Hercules – library is for a log which output events to Hercules.

LogEvent instances are mapped into Hercules events by this rules:

• Timestamp (mandatory) corresponds to:

  • Hercules event build-timestamp - a UtcDateTime of Timestamp.

  • UtcOffset tag - a long tag with offset from UTC expressed in 100-ns ticks.

• MessageTemplate ---> MessageTemplate tag of string type.

• RenderedMessage ---> MessageTemplate rendered to log string with templates replaced to corresponding values from Properties.

• Properties dictionary corresponds to a container with the same name. This container contains a tag for each pair. Keys are translated as-is, and the values are handled according to following conventions:

  • If the value is a primitive scalar or a vector of primitive scalars natively supported by Hercules (such as int, long, guid, string, etc), it's mapped as-is.

  • Otherwise the value gets converted to string: either stringified directly (if it properly overrides ToString()) or serialized to JSON. No further container-like structure is allowed, all values end up being 'flat'.

• Exception object corresponds to a container with the same name and following tags:

  • Exception runtime type (e.g. System.NullReferenceException) ---> Type tag of type string.

  • Exception message ---> Message tag of type string.

  • Nested exceptions (e.g. InnerException and InnerExceptions for AggregateException) ---> InnerExceptions tag of type Vector which contains other exceptions in the same format.

  • Stacktrace of exception ---> StackTrace tag of type Vector of StackFrame. StackFrame is Container of the following tags which describe a point of code which executed when exception occured:

    • Function - a name of function (method).

    • Type - a type when Function is declared.

    • File - file name.

    • Line - line number.

    • Column - column number.

Logging + Tracing

... – library is for adding TraceId to logs.