Welcome to LogFlux! This comprehensive guide will walk you through setting up LogFlux in your application, from initial setup to advanced features. Whether you’re managing logs for a small project or a large-scale distributed system, this guide has you covered.

Quick Start

Step 1: Create Your Account

First, sign up for a free LogFlux account at dashboard.logflux.io/signup. No credit card required.

Step 2: Create an Application

Once logged in, create your first application:

  1. Navigate to the Dashboard
  2. Click “Create Application”
  3. Name your application (e.g., “production-api”)
  4. Select your preferred region (EU or US)
  5. Click “Create”

Step 3: Get Your API Key

After creating your application, you’ll receive an API key. Keep this secure – it’s your application’s authentication credential.

export LOGFLUX_API_KEY="lfx_prod_a1b2c3d4e5f6g7h8i9j0"

Installation

Node.js/JavaScript

npm install @logflux/sdk

const { Logflux } = require('@logflux/sdk');

const logger = new Logflux({
  apiKey: process.env.LOGFLUX_API_KEY,
  application: 'my-app',
  environment: 'production'
});

// Start logging
logger.info('Application started successfully');

Python

pip install logflux

from logflux import Logflux
import os

logger = Logflux(
    api_key=os.environ['LOGFLUX_API_KEY'],
    application='my-app',
    environment='production'
)

# Start logging
logger.info('Application started successfully')

Go

go get github.com/logflux-io/logflux-go

package main

import (
    "os"
    "github.com/logflux-io/logflux-go"
)

func main() {
    logger := logflux.New(logflux.Config{
        APIKey:      os.Getenv("LOGFLUX_API_KEY"),
        Application: "my-app",
        Environment: "production",
    })
    
    // Start logging
    logger.Info("Application started successfully")
}

Basic Logging

Log Levels

LogFlux supports standard log levels:

logger.debug('Detailed debug information');
logger.info('Informational messages');
logger.warn('Warning messages');
logger.error('Error messages');
logger.fatal('Fatal errors that cause application exit');

Structured Logging

Add context to your logs with structured data:

logger.info('User login', {
  userId: '12345',
  email: 'user@example.com',
  loginMethod: 'oauth',
  ipAddress: request.ip
});

logger.error('Payment processing failed', {
  orderId: 'ORD-789',
  amount: 99.99,
  currency: 'USD',
  error: error.message,
  stack: error.stack
});

Contextual Logging

Create logger instances with persistent context:

// Create a logger with request context
const requestLogger = logger.child({
  requestId: req.id,
  userId: req.user.id,
  sessionId: req.session.id
});

// All logs from this logger will include the context
requestLogger.info('Processing request');
requestLogger.debug('Fetching user data');
requestLogger.info('Request completed', { duration: 145 });

Advanced Features

Batch Logging

Optimize performance with batch logging:

const logger = new Logflux({
  apiKey: process.env.LOGFLUX_API_KEY,
  batchSize: 100,        // Send logs in batches of 100
  flushInterval: 5000    // Flush every 5 seconds
});

// Logs are automatically batched and sent efficiently
for (let i = 0; i < 1000; i++) {
  logger.info(`Processing item ${i}`);
}

Error Tracking

Automatically capture and format errors:

try {
  // Your application code
  processPayment(order);
} catch (error) {
  logger.error('Payment processing failed', {
    error: {
      message: error.message,
      stack: error.stack,
      code: error.code
    },
    order: order.toJSON()
  });
}

Performance Metrics

Track performance metrics alongside your logs:

const timer = logger.startTimer();

// Perform operation
await performDatabaseQuery();

timer.done({
  message: 'Database query completed',
  query: 'SELECT * FROM users',
  rows: result.length
});
// Automatically logs with duration

Custom Fields

Add custom fields that appear in all logs:

const logger = new Logflux({
  apiKey: process.env.LOGFLUX_API_KEY,
  defaultFields: {
    service: 'api-gateway',
    version: process.env.APP_VERSION,
    region: process.env.AWS_REGION
  }
});

Using the Inspector CLI

The LogFlux Inspector provides a powerful terminal interface for viewing logs:

Installation

# macOS
brew install logflux/tap/inspector

# Linux
curl -fsSL https://download.logflux.io/agent/install.sh | sudo bash

# Windows
scoop install logflux-inspector

Basic Usage

# Stream logs in real-time
logflux logs --app my-app --follow

# Search logs
logflux logs --app my-app --search "error"

# Filter by time range
logflux logs --app my-app --since 1h --until now

# Filter by log level
logflux logs --app my-app --level error,warn

# Export logs
logflux export --app my-app --format json > logs.json

Advanced Queries

# Complex search with multiple conditions
logflux query \
  --app my-app \
  --filter 'level:error AND service:payment' \
  --since 24h \
  --limit 100

# Aggregate logs
logflux stats \
  --app my-app \
  --group-by level \
  --interval 1h

Best Practices

1. Use Structured Logging

Instead of:

logger.info(`User ${userId} logged in from ${ipAddress}`);

Do this:

logger.info('User login', {
  userId: userId,
  ipAddress: ipAddress,
  timestamp: new Date().toISOString()
});

2. Include Request Context

Always include request identifiers for tracing:

app.use((req, res, next) => {
  req.logger = logger.child({
    requestId: req.id,
    method: req.method,
    path: req.path
  });
  next();
});

3. Log at the Right Level

  • DEBUG: Detailed information for debugging
  • INFO: General informational messages
  • WARN: Warning messages for potential issues
  • ERROR: Error messages for failures
  • FATAL: Critical errors causing application termination

4. Sanitize Sensitive Data

const sanitizedUser = {
  id: user.id,
  email: user.email.replace(/(.{2}).*(@.*)/, '$1***$2'),
  // Never log passwords, tokens, or credit card numbers
};

logger.info('User registered', { user: sanitizedUser });

5. Use Correlation IDs

Track requests across microservices:

const correlationId = req.headers['x-correlation-id'] || uuid();

const serviceLogger = logger.child({
  correlationId: correlationId,
  service: 'user-service'
});

// Pass correlation ID to downstream services
axios.get('https://api.internal/data', {
  headers: {
    'x-correlation-id': correlationId
  }
});

Monitoring and Alerting

Setting Up Alerts

Configure alerts in the LogFlux dashboard:

  1. Navigate to “Alerts” section
  2. Click “Create Alert”
  3. Define your conditions:
    level:error AND service:payment
threshold: 5 errors in 5 minutes
  4. Configure notification channels (Email, Slack, PagerDuty)

Dashboard Creation

Create custom dashboards for your logs:

  1. Go to “Dashboards”
  2. Click “Create Dashboard”
  3. Add widgets:
    • Log stream
    • Error rate graph
    • Response time histogram
    • Top errors table

Troubleshooting

Common Issues

Logs not appearing:

  • Check your API key is correct
  • Verify network connectivity
  • Ensure logs are being flushed (in batch mode)

Rate limiting:

  • Implement exponential backoff
  • Use batch logging
  • Contact support for limit increases

Missing fields:

  • Check field names (case-sensitive)
  • Verify data types
  • Ensure fields are not null/undefined

Next Steps

Now that you have LogFlux set up, explore these advanced features:

  1. Encryption: Enable field-level encryption for sensitive data
  2. Retention Policies: Configure automatic log archival
  3. Integrations: Connect with your existing tools (Grafana, DataDog, etc.)
  4. API Access: Build custom integrations with our REST API
  5. Compliance: Enable GDPR/HIPAA compliance features

Support

Need help? We’re here for you:

Welcome to LogFlux – happy logging!