Docker Container Logs Collection Action

Automatically collect and manage logs from all running Docker containers in your GitHub Actions workflow.

Features

• Automatic Log Collection: Gather logs from all running Docker containers
• Flexible Output: Stream to stdout or save to files for artifact upload
• Selective Filtering: Target specific containers by image name
• Configurable Limits: Control log volume with line count limits
• Cross-Shell Support: Works with different shell environments
• Easy Integration: Simple YAML configuration for any workflow

Quick Start

Add this action to your workflow to automatically collect Docker logs on failure:

- name: Collect Docker logs on failure
  if: failure()
  uses: step-security/gh-docker-logs@v2

Configuration

Input Parameters

Parameter	Description	Default	Required
dest	Destination folder to write log files. If not provided, logs are written to stdout. Files are named by container (e.g., redis.log)	stdout	No
images	Comma-delimited list of image names to filter containers. Supports exact matches (mongo:3.4.22) or name-only matches (mongo)	all containers	No
tail	Maximum number of lines to collect from each container	all	No
shell	Shell to execute commands	/bin/sh	No

Output Behavior

• stdout mode: Logs are printed directly to the workflow output
• file mode: Individual log files are created for each container in the specified directory
• filtering: Only containers matching the specified images are processed
• naming: Log files use container names with .log extension

Usage Examples

Basic Usage - Collect All Logs on Failure

  - name: Collect Docker logs on failure
    if: failure()
    uses: step-security/gh-docker-logs@v2

Selective Log Collection

- name: Collect specific service logs
  uses: step-security/gh-docker-logs@v2
  with:
    images: 'redis,mongo,postgres'
    tail: '100'

Save Logs as Artifacts

- name: Collect Docker logs to files
  if: failure()
  uses: step-security/gh-docker-logs@v2
  with:
    dest: './docker-logs'

- name: Archive logs
  if: failure()
  run: tar -czf docker-logs.tar.gz ./docker-logs

- name: Upload logs as artifact
  if: failure()
  uses: actions/upload-artifact@v4
  with:
    name: docker-logs
    path: docker-logs.tar.gz
    retention-days: 7

Custom Shell Environment

- name: Collect logs with custom shell
  if: failure()
  uses: step-security/gh-docker-logs@v2
  with:
    shell: '/bin/bash'

Best Practices

• Use with if: failure() to avoid unnecessary log collection on successful runs
• Set appropriate tail limits for large applications to prevent overwhelming output
• Filter by specific images when you only need logs from certain services
• Upload logs as artifacts for persistent access to debugging information
• Consider log retention policies when using artifact uploads

Common Use Cases

• CI/CD Debugging: Capture logs when tests fail
• Integration Testing: Monitor service interactions
• Performance Analysis: Collect logs for performance troubleshooting
• Security Auditing: Preserve container output for security reviews

License

This project is licensed under the MIT License - see the LICENSE file for details.

Support

• Report Issues
• View Documentation
• Step Security