Image API

Image API is a microservice that integrates and is reliant on https://github.com/moapis/authenticator for validating the tokens that it receives from the client and it is a specialized service that handles image processing and storage to S3 compatible storages directly from buffer without writing to disk. It interacts with a PostgreSQL database for storing relevant information. It can handle not only single/batch upload and image storage but also image resizing and overlaying one image over another and can also store mp4 videos.

• This is a RESTful API that is meant to run as a microservice in Docker along with Authenticator and Shop.
• Client requests are made to this API using Web gRPC protocol and require Envoy proxy to translate the request into native gRPC.

Accepted mime types: image/jpg, image/jpeg, image/png, image/gif, image/bmp, video/mp4

message ImageDimensions {
    uint32 width = 1;
    uint32 height = 2;
    uint32 alpha = 3;
}

message NewImageRequest {
    repeated bytes image = 1;
    ImageDimensions dimensions = 2; 
    string tkn = 3;
}

message NewImageResponse {
    repeated string link = 1;
    repeated NewImageResponseStruct Structure = 2;
}

message RemoveImageRequest {
    repeated string link = 1;
    string tkn = 2;
}

message RemoveImageResponse {
    string status = 1;
}

message NewImageResponseStruct {
    string originalLink = 1;
    string resizedLink = 2;
    uint32 originalID = 3;
    uint32 resizedID = 4;
}

// Valid positions for OverlayRequest are: "bottomright", "bottomleft", "topright", "center"
message OverlayRequest {
    bytes overlayImage = 1;
    bytes backgroundImage = 2;
    string position = 3;
    int32  resizeX = 4;
    int32  resizeY = 5;
    string tkn = 6;
}

message OverlayResponse {
    string link = 1;
}

service ImageService {
    rpc NewImageResize (NewImageRequest) returns (NewImageResponse);
    rpc NewImagePreserve (NewImageRequest) returns (NewImageResponse); 
    rpc NewImageResizeAndPreserve (NewImageRequest) returns (NewImageResponse);
    rpc NewImageResizeAtDimensions (NewImageRequest) returns (NewImageResponse);
    rpc RemoveImage(RemoveImageRequest) returns (RemoveImageResponse);
    rpc Overlay(OverlayRequest) returns (OverlayResponse);
}

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It uses https://github.com/minio/minio-go client library for interacting with S3.

It also uses https://github.com/anthonynsimon/bild for some of the image manipulation.

For more information regarding Google's gRPC protocol please visit: https://grpc.io/about/

Envoy docs: https://www.envoyproxy.io/docs/envoy/latest/intro/arch_overview/other_protocols/grpc

To regenerate the Go code from image_api.proto file please consult: https://grpc.io/docs/languages/go/basics/#generating-client-and-server-code

To generate web gRPC client Javascript code please refer to: https://grpc.io/blog/grpc-web-ga/

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Configuration

Below are the various environment variables that need to be propagated when deploying this service.

Postgresql database environment variables.

• IMAGEAPI_PQ_HOST
• IMAGEAPI_PQ_PORT
• IMAGEAPI_PQ_USER
• IMAGEAPI_PQ_PASS
• IMAGEAPI_PQ_DBNAME
• IMAGEAPI_PQ_SSLMODE

Image API grpc server configuration.

• IMAGEAPI_ADDR
• IMAGEAPI_PORT

Authenticator endpoint that it should exchange tokens with.

• AUTHENTICATOR_HOSTNAME

Exposed S3 storage client environment variables.

• S3_ENDPOINT
• S3_KEY
• S3_SECRET
• S3_TLS
• S3_DEFAULT_BUCKET

Below env vars default to minio if not set.

• S3_TEST_ENDPOINT
• S3_TEST_KEY
• S3_TEST_SECRET
• S3_TEST_TLS
• S3_TEST_BUCKET