wheels deploy logs

View deployment logs from servers.

Synopsis

wheels deploy:logs [options]

Description

The wheels deploy:logs command allows you to view Docker container logs from your deployed application and database containers. This is essential for troubleshooting issues, monitoring application behavior, and debugging production problems.

Options

servers=<string> - Specific servers to check (comma-separated list)
tail=<number> - Number of lines to show (default: 100)
--follow - Follow log output in real-time (default: false)
service=<string> - Service to show logs for: app or db (default: app)
since=<string> - Show logs since timestamp (e.g., "2023-01-01", "1h", "5m")

Examples

View recent application logs

wheels deploy:logs

Follow logs in real-time

wheels deploy:logs --follow

View last 50 lines from specific server

wheels deploy:logs tail=50 servers=web1.example.com

View database logs

wheels deploy:logs service=db

View logs from the last hour

wheels deploy:logs since=1h

Follow database logs from specific server

wheels deploy:logs service=db --follow servers=web2.example.com

View logs since specific date

wheels deploy:logs since=2024-01-15

How It Works

The command:

Connects to target servers via SSH
Executes docker logs on the specified container
Streams or displays the output based on options
Supports multiple servers with clear separation

Output Example

Single server logs

Wheels Deployment Logs
==================================================

[2024-01-15 14:30:00] INFO: Server started on port 3000
[2024-01-15 14:30:01] INFO: Database connection established
[2024-01-15 14:30:02] INFO: Wheels application initialized
[2024-01-15 14:35:00] INFO: Request processed: GET /
[2024-01-15 14:40:00] WARN: Slow query detected (1.2s)
[2024-01-15 14:45:00] ERROR: Failed to send email: SMTP connection refused

Multiple servers

Wheels Deployment Logs
==================================================

=== Server: web1.example.com ===

[2024-01-15 14:30:00] INFO: Server started on port 3000
[2024-01-15 14:35:00] INFO: Health check passed

=== Server: web2.example.com ===

[2024-01-15 14:30:05] INFO: Server started on port 3000
[2024-01-15 14:35:05] INFO: Health check passed

Use Cases

Real-time monitoring

# Monitor application logs
wheels deploy:logs --follow

# Monitor database logs
wheels deploy:logs service=db --follow

Troubleshooting errors

# View recent errors (combine with grep)
wheels deploy:logs tail=500 | grep ERROR

# Check specific time period
wheels deploy:logs since=30m | grep -i error

Database debugging

# View database startup logs
wheels deploy:logs service=db tail=200

# Monitor database queries
wheels deploy:logs service=db --follow | grep Query

Performance analysis

# Find slow queries
wheels deploy:logs service=db since=1h | grep "Slow query"

# Check request processing times
wheels deploy:logs since=1h | grep "Request processed"

Time Formats

The since parameter accepts various formats:

Relative: 5m, 2h, 1d, 1w
ISO 8601: 2024-01-15T14:30:00
Date only: 2024-01-15
Docker format: 2024-01-15T14:30:00.000000000Z

Service Selection

Application logs (default)

Shows logs from the main application container:

wheels deploy:logs

Database logs

Shows logs from the database container:

wheels deploy:logs service=db

Best Practices

Use tail wisely: Start with reasonable line counts to avoid overwhelming output
Follow sparingly: Use --follow only when actively monitoring
Filter at source: Use since to reduce data transfer
Combine with tools: Pipe to grep, awk, or other tools for analysis
Monitor both services: Check both app and database logs when troubleshooting

Troubleshooting

Container not found

Verify deployment is active with wheels deploy:status
Check service name matches (app or db)
Ensure container is running

No logs appearing

Container might be new with no logs yet
Check if logging is configured correctly
Verify Docker logging driver settings

SSH timeout

Logs might be very large
Use tail parameter to limit output
Use since to reduce time range

Permission denied

Ensure SSH user has Docker access
Check if user is in docker group
Verify sudo permissions if needed

Advanced Usage

Export logs to file

# Save logs for analysis
wheels deploy:logs tail=1000 > app-logs.txt

# Save database logs
wheels deploy:logs service=db since=1d > db-logs.txt

Continuous monitoring with timestamps

# Add timestamps if not present
wheels deploy:logs --follow | while read line; do
  echo "$(date '+%Y-%m-%d %H:%M:%S') $line"
done

Log analysis pipeline

# Count errors by type
wheels deploy:logs since=1h | grep ERROR | cut -d: -f3- | sort | uniq -c | sort -nr

Notes

Logs are retrieved directly from Docker containers
No log rotation or management is performed by this command
Large log files may take time to transfer
Follow mode requires stable SSH connection
Container must be running to view logs