Message Logging

Message logging is configured in the appsettings.json file of the Server project. Lagoon extends ASP.NET Core logging with a simplified console and a file logger.

Configuration example

{
  "Logging": {
    "LogLevel": {
      "Default": "Error"
    }
  },
  "Lagoon": {
    "DefaultLoggers": {
      "Enabled": false
    },
    "LightConsoleLogger": {
      "Enabled": true,
      "ShowQueries": false
    },
    "FileLogger": {
      "Enabled": true,
      "LogFilename": "MonApp.txt",
      "FolderPath": "C:\\Temp\\(Traces)",
      "MaxFileSize": "5M",
      "DayToKeep": 2,
      "ShowUser": true
    }
  }
}

`DefaultLoggers`

Option	Type	Default	Description
`Enabled`	`bool`	`false`	Indicates whether the pre-registered logging handlers in the environment are kept, such as `Console` or `EventLog`.

When Lagoon:DefaultLoggers:Enabled is not true, Lagoon calls ClearProviders() then adds its loggers according to the configuration.

`LightConsoleLogger`

Option	Type	Default	Description
`Enabled`	`bool`	`true` in development, `false` in production	Enables simplified logging to the console.
`ShowQueries`	`bool`	`true`	Indicates whether EF Core queries are logged to the console.

Notes

The simplified console displays application-specific messages, warnings, and errors. It is not activated when DefaultLoggers is enabled.

`FileLogger`

Option	Type	Default	Description
`AutoFlushLevel`	`LogLevel`	`None`	Minimum level at which each message is directly visible in the file. `None` means `Debug` in `DEBUG` build, otherwise `Error`.
`DayToKeep`	`int`	`2`	Number of days to keep trace files.
`Enabled`	`bool`	`true`	Enables logging to a file.
`FolderPath`	`string`	System temporary path	Folder containing log files.
`Format`	`LgFileLoggerFormat`	`IndentedJsonLines`	Format of the log file.
`LogFilename`	`string`	Solution name	Root name of the file in `FolderPath`.
`MaxFileSize`	`string`	`5M`	Maximum file size with unit `K`, `M`, or `G`.
`MaxFileSizeInByte`	`long`	`5242880`	Maximum file size in bytes.
`ShowUser`	`bool`	`false`	Logs the identifier of the connected user when available.
`ShowIpSource`	`bool`	`false`	Logs the source IP address when available.

File formats

Value	Description
`IndentedJsonLines`	Sequence of indented JSON objects, more readable for humans.
`JsonLines`	JSON Lines format: each line is a valid JSON value terminated by `\n`.

Viewing logs from the application

The /lg/trace route allows displaying application traces for users authorized by the Policies.LogReader policy, whose value is log.read.

Configuration example​

DefaultLoggers​

LightConsoleLogger​

FileLogger​

File formats​

Viewing logs from the application​