easel - A remote image processing server

Aims & Background

In our datacenter, there are two kinds of machines. Machines with GPU, and those without GPU.

This library lets machines w/o GPU utilize remote GPU power via grpc protocol.

Croquis

• Server must be installed to machines with GPU.
  It accepts GLSL shaders, uniform variables (including textures), and vertexes, then render an image and send it back to clients.
• Client CLI is a CLI version of client implementation.
• Client Daemon is a daemon version of client implementation. It monitors a SQL table and process images according to table entries. This daemon could be useful for PHP front-ends.

Implementation

/easel-server the entrypoint of "server" executable.
/easel-client-cli: the entrypoint of "client-cli" executable.
/easel-client-daemon: the entrypoint of "client-daemon" executable.

/image-filters: GLSL shaders. Currently, there is only a lanczos10 filter.
/easel-server/impl:
/proto: grpc definitions.
/util: utility functions.

/test-images: image materials for testing.

Known Issues

• lanczos10 filter cannot handles alpha channel correctly.

How to run

Common Prerequirements

• golang: Use latest version.

Server

Prerequirements

# GLFW
sudo apt install libglfw3-dev
#
go get -u "github.com/go-gl/gl/v4.1-core/gl"
go get -u "github.com/go-gl/glfw/v3.2/glfw"
go get -u "github.com/Sirupsen/logrus"
go get -u "github.com/golang/protobuf/protoc-gen-go"
go get -u "google.golang.org/grpc"
go get -u "github.com/chai2010/webp"
go get -u "github.com/go-sql-driver/mysql"

Build

go get -u -d "github.com/ledyba/easel/easel-server"
go generate "github.com/ledyba/easel/easel-server"
go install "github.com/ledyba/easel/easel-server"

or, to cross-compile,

mkdir -p $GOPATH/src/githuc.com/ledyba/
cd $GOPATH/src/githuc.com/ledyba/
git clone "git@github.com:ledyba/easel.git"
cd easel
go generate "github.com/ledyba/easel/easel-server"
GOOS=linux GOARCH=amd64 go build -o easel-server "github.com/ledyba/easel/easel-server"

Create Certificates

# create self-signed ca
openssl req -new -x509 -days 3650 -newkey rsa:2048 -nodes -keyout ca.key -out ca.crt
# create client key
openssl req -new -newkey rsa:2048 -nodes -keyout client.key -out client.csr
# sign
openssl x509 -req -days 365 -in client.csr -CA ca.crt -CAkey ca.key -set_serial 01 -out client.crt

Command line flags

% ./bin/easel-server -h
Usage of ./easel-server:
  -cert string
    	cert file
  -cert_key string
    	private key file
  -help
    	Print help and exit
  -listen string
    	listen addr (default ":3000")

./easel-server \
    -cert=server.crt \
    -cert_key=server.key
    -listen "192.168.0.10:3000"

Client Daemon

Build

go get -u -d "github.com/ledyba/easel/easel-client-daemon"
go generate "github.com/ledyba/easel/easel-client-daemon"
go install "github.com/ledyba/easel/easel-client-daemon"

or, to cross-compile,

mkdir -p $GOPATH/src/githuc.com/ledyba/
cd $GOPATH/src/githuc.com/ledyba/
git clone "git@github.com:ledyba/easel.git"
cd easel
go generate "github.com/ledyba/easel/easel-client-daemon"
GOOS=linux GOARCH=amd64 go build -o easel-client-daemon "github.com/ledyba/easel/easel-client-daemon"

Command line flags

% ./easel-client-daemon -h
Usage of ./easel-client-daemon:
 -cert string
     cert file
 -cert_key string
     private key file
 -db string
     db address (default "user:password@tcp(host:port)/dbname")
 -filter string
     applied filter name. (default "lanczos")
 -filter_lobes int
     lobes parameter (default 10)
 -help
     Print help and exit
 -server string
     server to connect (default "localhost:3000")
 -workers int
     workers to run (default 10)

Example:

easel-client-daemon \
    -cert=client.crt \
    -cert_key=cert.key \
    -db="test:hoge@tcp(localhost:3306)/easel" \
    -server="192.168.0.10:3000"

Client CLI

Build

go get -u -d "github.com/ledyba/easel/easel-client-cli"
go generate "github.com/ledyba/easel/easel-client-cli"
go install "github.com/ledyba/easel/easel-client-cli"

or, to cross-compile,

mkdir -p $GOPATH/src/githuc.com/ledyba/
cd $GOPATH/src/githuc.com/ledyba/
git clone "git@github.com:ledyba/easel.git"
cd easel
go generate "github.com/ledyba/easel/easel-client-cli"
GOOS=linux GOARCH=amd64 go build -o easel-client-cli "github.com/ledyba/easel/easel-client-cli"

Command line flags

% ./easel-client-cli -h
Usage of ./easel-client-cli:
  -cert string
    	cert file
  -cert_key string
    	private key file
  -filter string
    	applied filter name. (default "lanczos")
  -filter_lobes int
    	lobes parameter (default 10)
  -help
    	Print help and exit
  -quality float
    	quality (default 95)
  -scale float
    	scale (default 2)
  -server string
    	server to connect (default "localhost:3000")

Example:

./easel-client-cli \
    -cert=client.crt \
    -cert_key=cert.key \
    test-images/momiji.png