Render GIF

RDR_CMP/rader.go

@@ -7,7 +7,6 @@ import (
 	"net/http"
 	"net/url"
 	"strings"
-	"time"
 )
 
 type Response struct {
@@ -30,13 +29,7 @@ type Response struct {
 	} `json:"response"`
 }
 
-func Time() string {
-	currentTime := time.Now()
-	return currentTime.Format("20060102")
-}
-
-// time : YYYYMMDD | 20241226
-func GetImages(apikey, time string) ([]string, error) {
+func GetImagesURL(apikey, time string) ([]string, error) {
 	URL := "http://apis.data.go.kr/1360000/RadarImgInfoService/getCmpImg"
 	params := url.Values{}
 	params.Add("serviceKey", apikey)

krapo.go

@@ -1,3 +1,12 @@
 package krapo
 
-import _ "github.com/fluffy-melli/krapo/RDR_CMP"
+import (
+	"time"
+
+	_ "github.com/fluffy-melli/krapo/RDR_CMP" // https://www.data.go.kr/tcs/dss/selectApiDataDetailView.do?publicDataPk=15056924
+)
+
+func Time() string {
+	currentTime := time.Now()
+	return currentTime.Format("20060102")
+}

render/fetch.go

@@ -0,0 +1,38 @@
+package render
+
+import (
+	"fmt"
+	"image"
+	_ "image/gif"
+	_ "image/jpeg"
+	_ "image/png"
+	"net/http"
+	"strings"
+	"sync"
+)
+
+var FileCache = make(map[string]image.Image)
+var mu sync.RWMutex
+
+func LoadImageFromURL(ImageURL string) (image.Image, error) {
+	ImageURL = strings.TrimSpace(ImageURL)
+	mu.RLock()
+	img, exists := FileCache[ImageURL]
+	mu.RUnlock()
+	if exists {
+		return img, nil
+	}
+	resp, err := http.Get(ImageURL)
+	if err != nil {
+		return nil, fmt.Errorf("failed to fetch image from URL %s: %v", ImageURL, err)
+	}
+	defer resp.Body.Close()
+	img, _, err = image.Decode(resp.Body)
+	if err != nil {
+		return nil, fmt.Errorf("failed to decode image from URL %s: %v", ImageURL, err)
+	}
+	mu.Lock()
+	FileCache[ImageURL] = img
+	mu.Unlock()
+	return img, nil
+}

render/file.go

@@ -0,0 +1,23 @@
+package render
+
+import (
+	"bytes"
+	"fmt"
+	"os"
+)
+
+func Write(filename string, buf *bytes.Buffer) error {
+	if buf == nil {
+		return fmt.Errorf("buffer cannot be nil")
+	}
+	file, err := os.Create(filename)
+	if err != nil {
+		return fmt.Errorf("failed to create file: %v", err)
+	}
+	defer file.Close()
+	_, err = file.Write(buf.Bytes())
+	if err != nil {
+		return fmt.Errorf("failed to write data to file: %v", err)
+	}
+	return nil
+}

render/gifs.go

@@ -0,0 +1,54 @@
+package render
+
+import (
+	"bytes"
+	"image"
+	"image/color"
+	"image/gif"
+)
+
+func GIF(urls []string, delay int) (*bytes.Buffer, error) {
+	var images []*image.Paletted
+	var delays []int
+	for _, url := range urls {
+		img, err := LoadImageFromURL(url)
+		if err != nil {
+			return nil, err
+		}
+		palette := Palette(img)
+		palettedImage := image.NewPaletted(img.Bounds(), palette)
+		for y := 0; y < palettedImage.Bounds().Dy(); y++ {
+			for x := 0; x < palettedImage.Bounds().Dx(); x++ {
+				palettedImage.Set(x, y, img.At(x, y))
+			}
+		}
+		images = append(images, palettedImage)
+		delays = append(delays, delay)
+	}
+	var buf bytes.Buffer
+	err := gif.EncodeAll(&buf, &gif.GIF{
+		Image: images,
+		Delay: delays,
+	})
+	if err != nil {
+		return nil, err
+	}
+	return &buf, nil
+}
+
+func Palette(frame image.Image) color.Palette {
+	colorSet := make(map[color.Color]struct{})
+	for y := 0; y < frame.Bounds().Dy(); y++ {
+		for x := 0; x < frame.Bounds().Dx(); x++ {
+			colorSet[frame.At(x, y)] = struct{}{}
+		}
+	}
+	var colors []color.Color
+	for c := range colorSet {
+		colors = append(colors, c)
+	}
+	if len(colors) > 256 {
+		colors = colors[:256]
+	}
+	return colors
+}

test/module_test.go

@@ -0,0 +1,25 @@
+package main
+
+import (
+	"log"
+	"testing"
+
+	"github.com/fluffy-melli/krapo"
+	"github.com/fluffy-melli/krapo/RDR_CMP"
+	"github.com/fluffy-melli/krapo/render"
+)
+
+func Test(t *testing.T) {
+	urls, err := RDR_CMP.GetImagesURL("", krapo.Time())
+	if err != nil {
+		log.Fatalln(err)
+	}
+	gif, err := render.GIF(urls, 5)
+	if err != nil {
+		log.Fatalln(err)
+	}
+	err = render.Write("./test.gif", gif)
+	if err != nil {
+		log.Fatalln(err)
+	}
+}