Application settings

The process of releasing software often starts with deployment to a staging environment, and after quality is assured the software is promoted to production. To minimize the risk of introducing new bugs one would like to promote the same binary, but with changes to the configuration. This means that configuration cannot be defined at compile-time, it must be applied at run-time. This is where the story of application settings begin.

The initiative from Microsoft to introduce Microsoft.Extensions.Configuration meant that other libraries, like Serilog, had a solid foundation to build their own configuration upon. This sink, in combination with Serilog.Settings.Configuration, supports application configuration by using Microsoft.Extensions.Configuration.Json or any other provider. The limited type system in JSON however forces us to write some of the configuration parameters in a slightly different way. The following chapters will list all configurable parameters and highlights those that in JSON have a different format than those defined in code.

Grafana Loki sink

Parameter name	CLR type	JSON type	JSON remarks	JSON example
uri	string	string
labels	IEnumerable<LokiLabel>	array of objects
propertiesAsLabels	IEnumerable<string>	array of strings
credentials	LokiCredentials	object
restrictedToMinimumLevel	LogEventLevel	string	See Enum.Parse	"Verbose"
batchPostingLimit	int	integer
queueLimit	int	integer
period	TimeSpan	string	See TimeSpan.Parse	"00:00:02"
textFormatter	ITextFormatter	string	See Type.GetType	"MyNamespace.MyClass, MyAssembly"
httpClient	ILokiHttpClient	string	See Type.GetType	"MyNamespace.MyClass, MyAssembly"
reservedPropertyRenamingStrategy	IReservedPropertyRenamingStrategy	string	See Type.GetType	"MyNamespace.MyClass, MyAssembly"
useInternalTimestamp	bool	boolean

Parameters description

• uri - the root URI of Loki
• labels - the global log event labels, which will be user for enriching all requests
• propertiesAsLabels - the list of properties, which should be mapped to Loki labels. The rest will be passed as a part of payload and could be used, using Loki's | json parser
• credentials - credentials, which will be used for basic auth
• restrictedToMinimumLevel - the minimum level for events passed through the sink
• batchPostingLimit - the maximum number of events to post in a single batch. Default value is 1000
• queueLimit - the maximum number of events stored in the queue in memory, waiting to be posted over the network. Default value is infinitely
• period - the time to wait between checking for event batches. Default value is 2 seconds
• textFormatter - the formatter rendering individual log events into text, for example JSON formater
• httpClient - the customizable HttpClient
• reservedPropertyRenamingStrategy - the strategy, used for property renaming in cases of collisions
• useInternalTimestamp - should use internal sink timestamp instead of application one to use as log timestamp