Lithium/pipeline.go

package main

import (
	"encoding/json"
	"errors"
	"fmt"
	"io/fs"
	"log"
	"os"
	"path/filepath"
)

// Pipelines

const (
	Image PipelineType = iota
	Video
)

type PipelineType int

type IPipeline interface {
	GetName() string
	GetType() PipelineType
	GetSteps() []Step
}

type Pipeline struct {
	Name           string       `json:"name"`
	Type           PipelineType `json:"type"`
	RemoveMetadata bool         `json:"remove_metadata"`
	Steps          []Step       `json:"steps"`
}

func (p Pipeline) GetName() string {
	return p.Name
}

func (p Pipeline) GetType() PipelineType {
	return p.Type
}

func (p Pipeline) GetSteps() []Step {
	return p.Steps
}

type ImagePipeline struct {
	Pipeline
}

type VideoPipeline struct {
	Pipeline
}

// Steps

type StepType int

const (
	TypeResizeImageStep StepType = iota
	TypeCompressImageStep
)

type Step struct {
	Name string
	Type StepType
}

func (s Step) Translate() (IExecutableStep, error) {
	var step IExecutableStep
	switch s.GetType() {
	case TypeResizeImageStep:
		step = ResizeImageStep{s}
	case TypeCompressImageStep:
		step = CompressImageStep{s}
	}

	if step == nil {
		return nil, errors.New("invalid type")
	}

	return step, nil
}

func (s Step) GetType() StepType {
	return s.Type
}

func (s Step) GetName() string {
	return s.Name
}

type IExecutableStep interface {
	Execute()
}

// Resize image

type ResizeImageStep struct {
	Step
}

func (s ResizeImageStep) Execute() {
	// TODO
}

// Compress image

type CompressImageStep struct {
	Step
}

func (s CompressImageStep) Execute() {
	// TODO
}

// Deserialization

func DeserializePipelines(pipelines [][]byte) []IPipeline {
	var values []IPipeline

	for _, pipeline := range pipelines {
		var deserializedObject Pipeline
		err := json.Unmarshal(pipeline, &deserializedObject)
		if err != nil {
			log.Fatalf("Could not deserialize pipelines config: %s", err)
		}
		values = append(values, deserializedObject)
	}

	return values
}

func LoadPipelines() []IPipeline {
	var files [][]byte

	path, _ := os.Getwd()

	err := filepath.Walk(path+"/pipelines", func(path string, info fs.FileInfo, err error) error {
		if err == nil && info.IsDir() == false {
			fmt.Println(path)
			data, _ := os.ReadFile(path)
			files = append(files, data)
		}

		return nil
	})

	if err != nil {
		panic(err)
	}

	return DeserializePipelines(files)
}