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Overview

The v2 API provides simple global logging functions for backward compatibility. These functions offer a quick way to log messages without creating a logger instance.
The v2 API is legacy and maintained for backward compatibility. For new code, consider using the v3 Logger API which provides structured logging, multiple formatters, and better performance.

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Functions

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InfoLog

Logs an informational message. 
func InfoLog(message string)
Parameters:
  • message - The informational message to log
Behavior:
  • Displays message in yellow color to terminal
  • Saves to log file if SAVE_LOG_FILE=1
  • Sends to Slack if NOTIFICATION_INFO_LOG=1
Example: 
go_logs.InfoLog("Server started on port 8080")
Environment Variables:
  • SAVE_LOG_FILE - Enable file logging (0 or 1)
  • NOTIFICATION_INFO_LOG - Enable Slack notifications (0 or 1)
Source Reference: logs.go:54-74

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ErrorLog

Logs an error message. 
func ErrorLog(message string)
Parameters:
  • message - The error message to log
Behavior:
  • Displays message in red color to terminal
  • Saves to log file if SAVE_LOG_FILE=1
  • Sends to Slack if NOTIFICATION_ERROR_LOG=1
Example: 
go_logs.ErrorLog("Failed to connect to database")
Environment Variables:
  • SAVE_LOG_FILE - Enable file logging (0 or 1)
  • NOTIFICATION_ERROR_LOG - Enable Slack notifications (0 or 1)
Source Reference: logs.go:32-52

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WarningLog

Logs a warning message. 
func WarningLog(message string)
Parameters:
  • message - The warning message to log
Behavior:
  • Displays message in yellow color to terminal
  • Saves to log file if SAVE_LOG_FILE=1
  • Sends to Slack if NOTIFICATION_WARNING_LOG=1
Example: 
go_logs.WarningLog("Database connection pool nearly exhausted")
Environment Variables:
  • SAVE_LOG_FILE - Enable file logging (0 or 1)
  • NOTIFICATION_WARNING_LOG - Enable Slack notifications (0 or 1)
Source Reference: api.go:267-291
This function was previously missing from the API, even though the notificationLogWarning configuration variable was loaded. It has been added to provide complete logging level support.

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SuccessLog

Logs a success message. 
func SuccessLog(message string)
Parameters:
  • message - The success message to log
Behavior:
  • Displays message in green color to terminal
  • Saves to log file if SAVE_LOG_FILE=1
  • Sends to Slack if NOTIFICATION_SUCCESS_LOG=1
Example: 
go_logs.SuccessLog("Operation completed successfully")
Environment Variables:
  • SAVE_LOG_FILE - Enable file logging (0 or 1)
  • NOTIFICATION_SUCCESS_LOG - Enable Slack notifications (0 or 1)
Source Reference: logs.go:76-96

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FatalLog

Logs a fatal message and terminates the program. 
func FatalLog(message string)
Parameters:
  • message - The fatal message to log
Behavior:
  • Displays message in red color with bomb emoji (💣) to terminal
  • Saves to log file if SAVE_LOG_FILE=1
  • Sends to Slack if NOTIFICATION_FATAL_LOG=1
  • Terminates the program by calling log.Fatal()
Example: 
go_logs.FatalLog("Database connection failed")
// Program exits here
Environment Variables:
  • SAVE_LOG_FILE - Enable file logging (0 or 1)
  • NOTIFICATION_FATAL_LOG - Enable Slack notifications (0 or 1)
This function calls log.Fatal() which terminates the program with os.Exit(1). Use only for unrecoverable errors.
Source Reference: logs.go:8-30

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Usage Examples

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Basic Logging

package main

import "github.com/drossan/go_logs"

func main() {
    go_logs.InfoLog("Application starting")
    
    if err := connectDB(); err != nil {
        go_logs.ErrorLog("Failed to connect to database")
        return
    }
    
    go_logs.SuccessLog("Database connected")
}

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Error Handling

func processFile(path string) error {
    data, err := os.ReadFile(path)
    if err != nil {
        go_logs.ErrorLog(fmt.Sprintf("Failed to read file: %v", err))
        return err
    }
    
    go_logs.InfoLog("File processed successfully")
    return nil
}

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Fatal Errors

func initApp() {
    config, err := loadConfig()
    if err != nil {
        go_logs.FatalLog("Cannot start without configuration")
        // Program exits here
    }
    // This line only executes if config loaded successfully
}

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Color Output

The v2 API uses the fatih/color package to provide colored terminal output:
FunctionColorEmoji
InfoLogYellow-
ErrorLogRed-
WarningLogYellow-
SuccessLogGreen-
FatalLogRed💣

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File Logging

When SAVE_LOG_FILE=1, all log messages are written to a file: 
export SAVE_LOG_FILE=1
export LOG_FILE_NAME=app.log
export LOG_FILE_PATH=/var/log

go_logs.InfoLog("This will be written to /var/log/app.log")

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Slack Notifications

Enable Slack notifications for specific log levels: 
export SLACK_TOKEN=xoxb-your-token
export SLACK_CHANNEL_ID=C123456
export NOTIFICATION_ERROR_LOG=1
export NOTIFICATION_FATAL_LOG=1

go_logs.ErrorLog("This error will be sent to Slack")

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Migration to V3

The v2 API is simple but lacks structured logging. Consider migrating to v3: V2 (Legacy): 
go_logs.InfoLog("User login: user-123")
V3 (Recommended): 
logger.Info("User login", go_logs.String("user_id", "user-123"))
See the Migration Guide for details.

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