Storage Provider Reference

Slink supports multiple storage providers for storing images. By default, the application uses the local file system to store images. However, you can configure the application to use a different storage provider by setting the STORAGE_PROVIDER environment variable.

Note

The following storage providers are supported: local, smb and s3.

Local Storage Provider

The local storage provider stores images on the local filesystem. This is the default provider and requires no additional configuration beyond specifying the storage directory.

Caution

To persist locally saved images when using Docker, you need to mount the /app/slink/images directory to the host filesystem.

Configuration:

• STORAGE_PROVIDER=local
• Images are stored in /app/slink/images
• Cache files are stored in /app/slink/cache

SMB (Samba) Storage Provider

The SMB storage provider allows you to store images on a network share using the SMB/CIFS protocol. This is useful for centralized storage in enterprise environments.

Required Configuration:

• STORAGE_PROVIDER=smb
• SMB_HOST - The hostname or IP address of your SMB server
• SMB_SHARE - The name of the SMB share to use
• SMB_USERNAME - Username for authentication
• SMB_PASSWORD - Password for authentication

Optional Configuration:

• SMB_WORKGROUP - The SMB workgroup (defaults to ‘workgroup’)

Example Docker Compose configuration:

environment:
  STORAGE_PROVIDER: smb
  SMB_HOST: 192.168.1.100
  SMB_SHARE: slink-storage
  SMB_USERNAME: slink-user
  SMB_PASSWORD: your-secure-password
  SMB_WORKGROUP: workgroup

Note

The SMB provider automatically creates the required directory structure (slink/images and slink/cache) on the remote share.

Amazon S3 Storage Provider

The Amazon S3 storage provider stores images in an AWS S3 bucket. This is ideal for cloud deployments and provides scalable object storage.

Required Configuration:

• STORAGE_PROVIDER=s3
• AMAZON_S3_REGION - AWS region where your bucket is located (e.g., us-east-1)
• AMAZON_S3_BUCKET - Name of your S3 bucket
• AMAZON_S3_ACCESS_KEY_ID - AWS access key ID
• AMAZON_S3_SECRET_ACCESS_KEY - AWS secret access key

Example Docker Compose configuration:

environment:
  STORAGE_PROVIDER: s3
  AMAZON_S3_REGION: us-east-1
  AMAZON_S3_BUCKET: my-slink-bucket
  AMAZON_S3_ACCESS_KEY_ID: EXAMPLEKEYID
  AMAZON_S3_SECRET_ACCESS_KEY: exampleSecretKey

Tip

For security best practices, consider using IAM roles instead of access keys when running on AWS infrastructure, or use AWS Secrets Manager for credential management.

Note

The S3 provider stores images directly in the bucket root with the following structure:

• Original images: {filename}
• Cached/transformed images: cache/{transformed-filename}

Storage Provider Architecture

Slink uses a proxy pattern to abstract storage operations. The StorageProxy class automatically routes operations to the configured storage provider based on the STORAGE_PROVIDER environment variable.

Supported Operations:

• Upload files with automatic directory creation
• Read and write file content
• Delete files
• Check file existence
• Image transformation and caching

Directory Structure: All storage providers maintain a consistent directory structure:

• slink/images/ - Original uploaded images
• slink/cache/ - Transformed/cached images