Pical

Pical is an on-the-fly image manipulation application. It uses sharp for image manipulation application.

Getting Started

docker run -d -p 8080:8080 pical/pical

Generating URL

Unsigned URL

<domain>/p/<path>@<format>?<query>

Signed URL

<domain>/s/<signature>/<path>@<format>?<query>

• signature: Add PICAL_KEY to the start of /<path>@<format>?<query> and calculate the HMAC digest using SHA256, and encode the first 32 bytes result with URL-safe Base64. @pical/signature can be used to generate the signature.
• path: Path of the image. It is the relative path from the base directory if it is using local storage. It is the relative path from the root directory if it is using S3 storage.
• format: Format of the output image. E.g. png, jpg, webp. original is supported without transformation.
• query: Query string for pass parameter to sharp. E.g. format[progressive]=true&resize[width]=300&greyscale=true. It is parsed by qs and it is passed by <method>[<parameter>] (except format is for toFormat). Please refer to sharp documentation.

Configuration

Pical can be configure by environment variable.

Local Storage

Default storage for Pical.

• PICAL_LOCAL_BASE_DIR: (Optional) /data by default.

S3 Storage

To enable S3 storage, PICAL_S3_END_POINT, PICAL_S3_BUCKET, PICAL_S3_ACCESS_KEY, and PICAL_S3_SECRET_KEY must be set.

• PICAL_S3_END_POINT: S3 Endpoint
• PICAL_S3_BUCKET: S3 Bucket
• PICAL_S3_ACCESS_KEY: S3 Access Key
• PICAL_S3_SECRET_KEY: S3 Secret Key
• PICAL_S3_USE_SSL: (Optional) Enable SSL connection to S3 endpoint. true by default.
• PICAL_S3_PORT: (Optional) Port of the S3 Endpoint
• PICAL_S3_REGION: (Optional)
• PICAL_S3_SESSION_TOKEN: (Optional)
• PICAL_S3_PART_SIZE: (Optional)

Other

• PICAL_KEY: Key for generating signature.
• PICAL_SALT: Salt for generating signature.
• NODE_ENV: (Optional) production by default.
• PICAL_UNSAFE_PLAIN: (Optional) Allow unsigned url if it is set to true. false if NODE_ENV is set to production by default.
• PICAL_PORT: (Optional) 8080 by default.
• PICAL_CACHE: (Optional) max-age header. 604800 by default.