Monolog CLI viewer

A simple tool to format monolog output into more readable form

Installation

1. Download latest binary for your OS from releases
2. Place the executable in your system PATH and ensure it has runing priviliges

Usage

Add mcv or mcv.exe into the pipeline that outputs the monolog logs. Some examples:

• cat monolog.log | grep 'user deleted' | mcv - for searching a specific entry
• tail -f monolog.log | mcv - for live preview of a file
• docker logs php-nginx -f | mcv.exe - for a live preview of docker logs

Parameters

The following parameters are supported

Param	Description	Default
-t	Name of the template to use	normal
-i	Template body to be used instead of predefined ones. See Templates for more.

As well as the following flags

Flag	Description
-T	List all templates available to use
-c	Disable colors in the output
-f	Show ==> file.name <== lines from tail command
-n	Don't add empty lines between entries
-p	Show only parsed lines. Doesn't affect -f
-test	Run the config against a predefined data-set

Templates

The application uses GoLang textTemplates with all fields from incoming monolog JSON available at root level, and traversable by dot-notation, and starting with a . (dot). Example: {{.message}}, and {{.channel}}. See Additional Fields for more.

Whenever a field in the tamplete will contain some sub-values (i.e. {{._context}}) it will display a map (map[id:123]). The full path of {{._context.id}} will just display the value 123.

When the requested path will not be present at all, it will display <no value>

Additional Fields

Additional fields are added to the values from monolog to be available in the template. They are:

• _colors - colors and text formatting options. This value contains the following sub-values:
  • red, green, yellow, blue, purple, cyan, white for colors
  • bold, underline, strike, italic for formatting
  • reset - for resetting the text output back to normal
• _color - one of the available colors based on monolog log level
  • DEBUG - white
  • INFO - cyan
  • NOTICE - green
  • WARNING - yellow
  • ERROR - purple
  • CRITICAL - red
  • ALERT - red
  • EMERGENCY - red
• _colorR - alias for _colors.reset
• _level - string representation of the int values in monolog level
• _dateTime - a Y-m-d H:i:s formatted value passed in timestamp or datetime fields of the monolog JSON
• _context and _extra - string representations of the JSON object passed in context and extra monolog fields
• _contextPretty and _extraPretty pretty-formatted versions of the fields

Behind the scenes

MCV parses each line of the incoming data and tries to display it using a provided template.

As of now the JSON and Line formatters are supported with their default config and default message structure.

When the received line is not a proper monolog entry in any accepted form, it is displayed as is, in raw value. Unless the -p flag has been provided.

As the program is designed to be used in pipeline it also recognizes the file name line from tail. It is ignored by default.