Add GitHub Actions build workflow and update Docker images

Push poorly written test can down the road another ten years

See merge request rrise/top-wallpaper!2

.gitea/workflows/build.yml

@@ -0,0 +1,43 @@
+on:
+  workflow_dispatch:
+    inputs:
+      tag:
+        description: 'Tag to build and push'
+        required: false
+        default: 'latest'
+  push:
+    tags:
+      - "v*"
+
+name: 🏗️✨ Build Workflow
+
+jobs:
+  Build:
+    name: 🖥️ 🔨 Build
+    runs-on: ubuntu-latest
+    steps:
+      - name: 📖 🔍 Checkout Repository Code
+        uses: actions/checkout@v4
+        with:
+          fetch-depth: 1
+          submodules: 'true'
+
+      - name: 🔑 🔐 Login to Docker Hub
+        uses: docker/login-action@v3
+        with:
+          username: ${{ secrets.DOCKER_USERNAME }}
+          password: ${{ secrets.DOCKER_PASSWORD }}
+
+      - name: 🏗️ 🔧 Set up Docker Buildx
+        uses: docker/setup-buildx-action@v3
+
+      - name: 🐳 🔨 Build Container
+        uses: docker/build-push-action@v6
+        with:
+          push: true
+          sbom: true
+          provenance: true
+          platforms: linux/arm64,linux/amd64
+          context: .
+          dockerfile: Dockerfile
+          tags: siteworxpro/top-wallpaper:${{ gitea.ref_name }}

.gitlab-ci.yml

@@ -0,0 +1,18 @@
+stages:
+  - Testing
+  - build
+
+include:
+  - component: $CI_SERVER_FQDN/shared/blueprints/golang-tests@v1.2.0
+    rules:
+      - if: '$CI_COMMIT_BRANCH'
+  - component: $CI_SERVER_FQDN/shared/blueprints/docker-build@v1.2.0
+    rules:
+      - if: '$CI_COMMIT_TAG'
+    inputs:
+      platform: "linux/amd64"
+      dockerHubUser: ${DOCKER_HUB_USER}
+      dockerHubPat: ${DOCKER_HUB_PAT}
+      stage: build
+      repo: siteworxpro/top-wallpaper
+      tag: "${CI_COMMIT_TAG}"

Dockerfile

@@ -1,4 +1,4 @@
-FROM siteworxpro/golang:1.24.0 AS build
+FROM siteworxpro/golang:1.24.3 AS build
 
 WORKDIR /app
 

LICENSE

@@ -0,0 +1,21 @@
+MIT License
+
+Copyright (c) 2025 Siteworx Professionals, LLC
+
+Permission is hereby granted, free of charge, to any person obtaining a copy
+of this software and associated documentation files (the "Software"), to deal
+in the Software without restriction, including without limitation the rights
+to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+copies of the Software, and to permit persons to whom the Software is
+furnished to do so, subject to the following conditions:
+
+The above copyright notice and this permission notice shall be included in all
+copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+SOFTWARE.

docker-compose.yml

@@ -0,0 +1,50 @@
+volumes:
+  redis_data:
+
+services:
+  traefik:
+    image: traefik:latest
+    container_name: traefik
+    ports:
+      - "80:80"
+      - "443:443"
+    volumes:
+      - "/var/run/docker.sock:/var/run/docker.sock"
+    restart: always
+    command:
+      - "--providers.docker=true"
+      - "--providers.docker.exposedByDefault=false"
+      - "--entrypoints.web.address=:80"
+      - "--entrypoints.web-secure.address=:443"
+      - "--accesslog=true"
+      - "--entrypoints.web.http.redirections.entryPoint.to=web-secure"
+      - "--entrypoints.web.http.redirections.entryPoint.scheme=https"
+      - "--entrypoints.web.http.redirections.entrypoint.permanent=true"
+
+  redis:
+    image: redis:latest
+    container_name: redis
+    restart: always
+    healthcheck:
+      test: ["CMD", "redis-cli", "ping"]
+      interval: 30s
+      timeout: 10s
+      retries: 3
+    volumes:
+      - redis_data:/data
+
+  api:
+    labels:
+      - "traefik.enable=true"
+      - "traefik.http.routers.api.entrypoints=web-secure"
+      - "traefik.http.routers.api.rule=Host(`localhost`) || Host(`127.0.0.1`)"
+      - "traefik.http.routers.api.tls=true"
+      - "traefik.http.services.api.loadbalancer.server.port=8080"
+    image: siteworxpro/top-wallpaper:v1.3.1
+    container_name: top-wallpaper
+    environment:
+      REDIS_URL: "redis"
+      CORS_ORIGINS: "https://localhost"
+    depends_on:
+      redis:
+        condition: service_healthy

go.mod

@@ -1,16 +1,17 @@
 module github.com/siteworxpro/top-wallpaper
 
-go 1.24.0
+go 1.24.3
 
 require (
 	github.com/labstack/echo/v4 v4.13.3
+	github.com/labstack/gommon v0.4.2
+	github.com/nfnt/resize v0.0.0-20180221191011-83c6a9932646
 	github.com/redis/go-redis/v9 v9.7.0
 )
 
 require (
 	github.com/cespare/xxhash/v2 v2.2.0 // indirect
 	github.com/dgryski/go-rendezvous v0.0.0-20200823014737-9f7001d12a5f // indirect
-	github.com/labstack/gommon v0.4.2 // indirect
 	github.com/mattn/go-colorable v0.1.13 // indirect
 	github.com/mattn/go-isatty v0.0.20 // indirect
 	github.com/valyala/bytebufferpool v1.0.0 // indirect

go.sum

@@ -17,6 +17,8 @@ github.com/mattn/go-colorable v0.1.13/go.mod h1:7S9/ev0klgBDR4GtXTXX8a3vIGJpMovk
 github.com/mattn/go-isatty v0.0.16/go.mod h1:kYGgaQfpe5nmfYZH+SKPsOc2e4SrIfOl2e/yFXSvRLM=
 github.com/mattn/go-isatty v0.0.20 h1:xfD0iDuEKnDkl03q4limB+vH+GxLEtL/jb4xVJSWWEY=
 github.com/mattn/go-isatty v0.0.20/go.mod h1:W+V8PltTTMOvKvAeJH7IuucS94S2C6jfK/D7dTCTo3Y=
+github.com/nfnt/resize v0.0.0-20180221191011-83c6a9932646 h1:zYyBkD/k9seD2A7fsi6Oo2LfFZAehjjQMERAvZLEDnQ=
+github.com/nfnt/resize v0.0.0-20180221191011-83c6a9932646/go.mod h1:jpp1/29i3P1S/RLdc7JQKbRpFeM1dOBd8T9ki5s+AY8=
 github.com/pmezard/go-difflib v1.0.0 h1:4DBwDE0NGyQoBHbLQYPwSUPoCMWR5BEzIk/f1lZbAQM=
 github.com/pmezard/go-difflib v1.0.0/go.mod h1:iKH77koFhYxTK1pcRnkKkqfTogsbg7gZNVY4sRDYZ/4=
 github.com/redis/go-redis/v9 v9.7.0 h1:HhLSs+B6O021gwzl+locl0zEDnyNkxMtf/Z3NNBMa9E=

http/handler.go

@@ -0,0 +1,25 @@
+package http
+
+import (
+	"github.com/labstack/echo/v4"
+	"github.com/siteworxpro/top-wallpaper/redis"
+	"net/http"
+)
+
+func Get(c echo.Context) error {
+
+	rc, err := redis.NewRedis()
+	if err != nil {
+		return c.String(http.StatusInternalServerError, "Internal Server Error: "+err.Error())
+	}
+
+	val, err := rc.Get(redis.CacheKey)
+
+	if err != nil || val == "" {
+		return c.NoContent(http.StatusNoContent)
+	}
+
+	c.Response().Header().Set("Cache-Control", "public, max-age=600")
+
+	return c.Blob(http.StatusOK, "image/jpeg", []byte(val))
+}

main.go

@@ -2,121 +2,35 @@ package main
 
 import (
 	"context"
-	"encoding/json"
-	"fmt"
 	"github.com/labstack/echo/v4"
 	"github.com/labstack/echo/v4/middleware"
 	"github.com/labstack/gommon/log"
-	"github.com/redis/go-redis/v9"
-	"io"
+	tphttp "github.com/siteworxpro/top-wallpaper/http"
+	"github.com/siteworxpro/top-wallpaper/reddit"
+	"github.com/siteworxpro/top-wallpaper/redis"
 	"net/http"
 	"os"
-	"strconv"
 	"strings"
-	"time"
 )
 
-type redditResponse struct {
-	Kind string `json:"kind"`
-	Data struct {
-		After     string `json:"after"`
-		Dist      int    `json:"dist"`
-		ModHash   string `json:"modhash"`
-		GeoFilter string `json:"geo_filter"`
-		Children  []struct {
-			Kind string `json:"kind"`
-			Data struct {
-				ApprovedAtUtc       interface{} `json:"approved_at_utc"`
-				Subreddit           string      `json:"subreddit"`
-				SelfText            string      `json:"selftext"`
-				Url                 string      `json:"url"`
-				UrlOverriddenByDest string      `json:"url_overridden_by_dest"`
-				MediaMetadata       map[string]struct {
-					Status string `json:"status"`
-					Id     string `json:"id"`
-					E      string `json:"e"`
-					M      string `json:"m"`
-					S      struct {
-						U string `json:"u"`
-						X int    `json:"x"`
-						Y int    `json:"y"`
-					} `json:"s"`
-					P []struct {
-						U string `json:"u"`
-						X int    `json:"x"`
-						Y int    `json:"y"`
-					} `json:"p"`
-				} `json:"media_metadata"`
-				Preview struct {
-					Enabled bool `json:"enabled"`
-					Images  []struct {
-						Source struct {
-							Url    string `json:"url"`
-							Width  int    `json:"width"`
-							Height int    `json:"height"`
-						} `json:"source"`
-					} `json:"images"`
-				} `json:"preview"`
-			} `json:"data"`
-		} `json:"children"`
-	} `json:"data"`
-}
-type CustomContext struct {
-	echo.Context
-	redis *redis.Client
-}
-
 func main() {
 
-	e := echo.New()
-	e.Logger.SetLevel(log.INFO)
+	ctx, fn := context.WithCancel(context.Background())
+	defer fn()
 
-	e.HideBanner = true
+	rc, err := redis.NewRedis()
 
-	// Middleware
-	e.Use(func(next echo.HandlerFunc) echo.HandlerFunc {
-		return func(c echo.Context) error {
-			redisUrl := os.Getenv("REDIS_URL")
-			if redisUrl == "" {
-				c.Logger().Warn("REDIS_URL not set, skipping redis connection. Use REDIS_URL to cache the image")
-
-				return next(&CustomContext{c, nil})
-			}
-
-			redisPort := os.Getenv("REDIS_PORT")
-			if redisPort == "" {
-				redisPort = "6379"
-			}
-
-			redisDb := os.Getenv("REDIS_DB")
-			if redisDb == "" {
-				redisDb = "0"
-			}
-
-			redisDbInt, err := strconv.ParseInt(redisDb, 10, 64)
 	if err != nil {
-				c.Logger().Warn("REDIS_DB is not a valid integer, skipping redis connection. Use REDIS_DB to cache the image")
-
-				return next(&CustomContext{})
+		log.Error("Could not initialize Redis client: ", err)
+		os.Exit(1)
 	}
 
-			cc := &CustomContext{c, redis.NewClient(&redis.Options{
-				Addr:     fmt.Sprintf("%s:%s", redisUrl, redisPort),
-				Password: os.Getenv("REDIS_PASSWORD"),
-				DB:       int(redisDbInt),
-			})}
+	e := echo.New()
+	e.AcquireContext().Set("redisClient", rc)
+	e.Logger.SetOutput(os.Stdout)
 
-			cmd := cc.redis.Ping(context.Background())
-
-			if cmd.Err() != nil {
-				c.Logger().Warn("could not connect to redis")
-
-				cc.redis = nil
-			}
-
-			return next(cc)
-		}
-	})
+	e.Logger.SetLevel(log.INFO)
+	e.HideBanner = true
 
 	e.Use(middleware.Logger())
 	e.Use(middleware.RequestID())
@@ -130,110 +44,20 @@ func main() {
 	if path == "" {
 		path = "/"
 	}
-	e.GET(path, func(c echo.Context) error {
-		cc := c.(*CustomContext)
 
-		var latestImageVal string
-		var err error
-		if cc.redis != nil {
-			latestImage := cc.redis.Get(context.TODO(), "latestImage")
-			latestImageVal, err = latestImage.Result()
-		}
-
-		if err != nil || latestImageVal == "" {
-			c.Logger().Info("Fetching latest image")
-			latestImageVal = getLatestImage()
-			if cc.redis != nil {
-				cmd := cc.redis.Set(context.TODO(), "latestImage", latestImageVal, 600*time.Second)
-				if cmd.Err() != nil {
-					c.Logger().Warn("could not cache image")
-				}
-			}
-		} else {
-			c.Logger().Info("Image name fetched from cache")
-		}
-
-		var imageData string
-		if cc.redis != nil {
-			latestImageBin := cc.redis.Get(context.TODO(), "latestImage:bin:"+latestImageVal)
-			imageData = latestImageBin.Val()
-		}
-
-		if imageData == "" {
-			response, err := http.Get(latestImageVal)
-			if err != nil {
-				return c.String(http.StatusInternalServerError, "Error fetching image")
-			}
-
-			if response.StatusCode != http.StatusOK {
-				return c.String(http.StatusInternalServerError, "Error fetching image")
-			}
-
-			defer func(Body io.ReadCloser) {
-				_ = Body.Close()
-			}(response.Body)
-
-			imageDataBytes, err := io.ReadAll(response.Body)
-			if err != nil {
-				return c.String(http.StatusInternalServerError, "Error fetching image")
-			}
-
-			imageData = string(imageDataBytes)
-
-			go func(data string) {
-				if cc.redis == nil {
-					return
-				}
-
-				_, err = cc.redis.Set(context.TODO(), "latestImage:bin:"+latestImageVal, data, 600*time.Second).Result()
-				if err != nil {
-					c.Logger().Warn("could not cache image")
-				}
-			}(imageData)
-		} else {
-			c.Logger().Info("Image data fetched from cache")
-		}
-
-		c.Response().Header().Set("Cache-Control", "public, max-age=600")
-
-		return c.Blob(http.StatusOK, "image/jpeg", []byte(imageData))
-	})
+	e.GET(path, tphttp.Get)
 
 	e.Logger.Info("Starting server at path " + path)
-	// start the server
 
 	port := os.Getenv("PORT")
 	if port == "" {
 		port = "8080"
 	}
 
+	ctx = redis.WithContext(ctx, rc)
+	ctx = context.WithValue(ctx, "logger", e.Logger)
+
+	go reddit.Fetch(ctx)
+
 	e.Logger.Fatal(e.Start(":" + port))
 }
-
-func getLatestImage() string {
-	response, err := http.Get("https://www.reddit.com/r/wallpaper/.json")
-	if err != nil {
-		panic(err)
-	}
-	defer func(Body io.ReadCloser) {
-		_ = Body.Close()
-	}(response.Body)
-
-	jsonBytes, err := io.ReadAll(response.Body)
-
-	redditData := redditResponse{}
-	err = json.Unmarshal(jsonBytes, &redditData)
-	if err != nil {
-		panic(err)
-	}
-
-	index := 1
-	url := redditData.Data.Children[index].Data.UrlOverriddenByDest
-
-	for strings.Contains(url, "gallery") {
-		index++
-		url = redditData.Data.Children[index].Data.UrlOverriddenByDest
-	}
-
-	return url
-}

reddit/client.go

@@ -0,0 +1,88 @@
+package reddit
+
+import (
+	"encoding/json"
+	"fmt"
+	"io"
+	"net/http"
+	"strings"
+)
+
+type redditResponse struct {
+	Kind string `json:"kind"`
+	Data struct {
+		After     string `json:"after"`
+		Dist      int    `json:"dist"`
+		ModHash   string `json:"modhash"`
+		GeoFilter string `json:"geo_filter"`
+		Children  []struct {
+			Kind string `json:"kind"`
+			Data struct {
+				ApprovedAtUtc       interface{} `json:"approved_at_utc"`
+				Subreddit           string      `json:"subreddit"`
+				SelfText            string      `json:"selftext"`
+				Url                 string      `json:"url"`
+				UrlOverriddenByDest string      `json:"url_overridden_by_dest"`
+				MediaMetadata       map[string]struct {
+					Status string `json:"status"`
+					Id     string `json:"id"`
+					E      string `json:"e"`
+					M      string `json:"m"`
+					S      struct {
+						U string `json:"u"`
+						X int    `json:"x"`
+						Y int    `json:"y"`
+					} `json:"s"`
+					P []struct {
+						U string `json:"u"`
+						X int    `json:"x"`
+						Y int    `json:"y"`
+					} `json:"p"`
+				} `json:"media_metadata"`
+				Preview struct {
+					Enabled bool `json:"enabled"`
+					Images  []struct {
+						Source struct {
+							Url    string `json:"url"`
+							Width  int    `json:"width"`
+							Height int    `json:"height"`
+						} `json:"source"`
+					} `json:"images"`
+				} `json:"preview"`
+			} `json:"data"`
+		} `json:"children"`
+	} `json:"data"`
+}
+
+func GetLatestImage(httpGet func(url string) (*http.Response, error)) (string, error) {
+
+	response, err := httpGet("https://www.reddit.com/r/wallpaper/.json")
+	if err != nil {
+		return "", err
+	}
+	defer func(Body io.ReadCloser) {
+		_ = Body.Close()
+	}(response.Body)
+
+	if response.StatusCode != http.StatusOK {
+		return "", fmt.Errorf("error fetching reddit data: %s", response.Status)
+	}
+
+	jsonBytes, err := io.ReadAll(response.Body)
+
+	redditData := redditResponse{}
+	err = json.Unmarshal(jsonBytes, &redditData)
+	if err != nil {
+		return "", err
+	}
+
+	index := 1
+	url := redditData.Data.Children[index].Data.UrlOverriddenByDest
+
+	for strings.Contains(url, "gallery") {
+		index++
+		url = redditData.Data.Children[index].Data.UrlOverriddenByDest
+	}
+
+	return url, nil
+}

reddit/client_test.go

@@ -0,0 +1,70 @@
+package reddit
+
+import (
+	"fmt"
+	"net/http"
+	"net/http/httptest"
+	"strings"
+	"testing"
+)
+
+func TestGetLatestImage(t *testing.T) {
+	// Mock Reddit API response
+	mockResponse := `{
+		"kind": "Listing",
+		"data": {
+			"after": null,
+			"dist": 1,
+			"modhash": "",
+			"geo_filter": "",
+			"children": [
+				{
+					"kind": "t3",
+					"data": {
+						"url_overridden_by_dest": "https://example.com/gallery",
+						"media_metadata": {},
+						"preview": {}
+					}
+				},
+				{
+					"kind": "t3",
+					"data": {
+						"url_overridden_by_dest": "https://example.com/image.jpg",
+						"media_metadata": {},
+						"preview": {}
+					}
+				}
+			]
+		}
+	}`
+
+	// Create a test server
+	server := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		if strings.Contains(r.URL.Path, "/r/wallpaper/.json") {
+			w.WriteHeader(http.StatusOK)
+			_, _ = w.Write([]byte(mockResponse))
+		} else {
+			w.WriteHeader(http.StatusNotFound)
+		}
+	}))
+	defer server.Close()
+
+	// Custom httpGet function for testing
+	httpGet := func(url string) (*http.Response, error) {
+		if strings.Contains(url, "/r/wallpaper/.json") {
+			return http.Get(server.URL + "/r/wallpaper/.json")
+		}
+		return nil, fmt.Errorf("unexpected URL: %s", url)
+	}
+
+	// Test the function
+	imageURL, err := GetLatestImage(httpGet)
+	if err != nil {
+		t.Fatalf("expected no error, got %v", err)
+	}
+
+	expectedURL := "https://example.com/image.jpg"
+	if imageURL != expectedURL {
+		t.Errorf("expected %s, got %s", expectedURL, imageURL)
+	}
+}

reddit/fetcher.go

@@ -0,0 +1,132 @@
+package reddit
+
+import (
+	"context"
+	"github.com/labstack/echo/v4"
+	"github.com/siteworxpro/top-wallpaper/redis"
+	"github.com/siteworxpro/top-wallpaper/resize"
+	"io"
+	"net/http"
+	"net/url"
+	"os"
+	"strconv"
+	"strings"
+	"time"
+)
+
+func Fetch(ctx context.Context) {
+	const defaultImageSize = 1600
+	const minImageSize = 100
+
+	rc, err := redis.FromContext(ctx)
+	if err != nil {
+		panic("Redis client not found in context: " + err.Error())
+	}
+
+	l := ctx.Value("logger").(echo.Logger)
+
+	var size int
+	if sizeS, ok := os.LookupEnv("MAX_SIZE"); ok {
+		size, err = strconv.Atoi(sizeS)
+		if err != nil {
+			size = defaultImageSize
+		}
+	} else {
+		size = defaultImageSize
+	}
+
+	if size < minImageSize {
+		size = defaultImageSize
+	}
+
+	for {
+		select {
+		case <-ctx.Done():
+
+			l.Info("Stopping Reddit fetcher...")
+			_ = rc.Close()
+
+			return
+		default:
+
+			val, err := rc.Get(redis.CacheKey)
+			if val != "" {
+				l.Info("Reddit image fetched from cache...")
+
+				break
+			}
+
+			l.Info("Fetching latest image from Reddit...")
+
+			latestImageVal, err := GetLatestImage(func(u string) (*http.Response, error) {
+
+				request := &http.Request{
+					Method: http.MethodGet,
+					Header: http.Header{
+						"User-Agent": []string{"Mozilla/5.0 (compatible; RedditBot/1.0; +https://www.reddit.com/wiki/redditauth)"},
+					},
+					URL: &url.URL{
+						Scheme: "https",
+						Host:   "www.reddit.com",
+						Path:   strings.TrimPrefix(u, "https://www.reddit.com"),
+					},
+				}
+
+				httpClient := &http.Client{
+					Timeout: 10 * time.Second,
+				}
+
+				response, err := httpClient.Do(request)
+
+				if err != nil {
+					l.Error("Error fetching image from Reddit: ", err)
+					return nil, err
+				}
+
+				if response.StatusCode != http.StatusOK {
+					l.Error("Error fetching image from Reddit: ", response.Status)
+					return nil, &echo.HTTPError{
+						Code:    response.StatusCode,
+						Message: "Error fetching image from Reddit",
+					}
+				}
+
+				return response, nil
+			})
+
+			response, err := http.Get(latestImageVal)
+			if err != nil {
+				l.Error("Error fetching image from Reddit: ", err)
+
+				break
+			}
+
+			if response.StatusCode != http.StatusOK {
+				l.Error("Error fetching image from Reddit: ", response.Status)
+
+				break
+			}
+
+			imageDataBytes, err := io.ReadAll(response.Body)
+			if err != nil {
+				l.Error("Error reading image data: ", err)
+				_ = response.Body.Close()
+				break
+			}
+
+			_ = response.Body.Close()
+
+			imageData := string(imageDataBytes)
+			resized, err := resize.Shrink(imageData, uint(size), 70)
+
+			err = rc.Set(redis.CacheKey, resized, 10*time.Minute)
+			if err != nil {
+				l.Warn("could not cache image")
+			}
+
+			l.Info("Reddit image fetched and resized successfully, cached for 10 minutes.")
+		}
+
+		time.Sleep(10 * time.Minute)
+	}
+}

redis/client.go

@@ -0,0 +1,118 @@
+package redis
+
+import (
+	"context"
+	"errors"
+	"fmt"
+	"github.com/redis/go-redis/v9"
+	"os"
+	"strconv"
+	"time"
+)
+
+type contextKey string
+
+const redisKey contextKey = "redisClient"
+
+const CacheKey = "top-wallpaper:latestImage"
+
+type Cache interface {
+	Get(key string) (string, error)
+	Set(key string, value string, expiration int64) error
+	Close() error
+}
+
+type Redis struct {
+	client *redis.Client
+}
+
+func NewRedis() (*Redis, error) {
+
+	redisUrl := os.Getenv("REDIS_URL")
+	if redisUrl == "" {
+		return nil, errors.New("REDIS_URL not set, cannot initialize Redis client")
+	}
+
+	redisPort := os.Getenv("REDIS_PORT")
+	if redisPort == "" {
+		redisPort = "6379"
+	}
+
+	redisDb := os.Getenv("REDIS_DB")
+	if redisDb == "" {
+		redisDb = "0"
+	}
+
+	redisDbInt, err := strconv.ParseInt(redisDb, 10, 64)
+	if err != nil {
+		return nil, errors.New("REDIS_DB is not a valid integer, cannot initialize Redis client")
+	}
+
+	rc := redis.NewClient(&redis.Options{
+		Addr:     fmt.Sprintf("%s:%s", redisUrl, redisPort),
+		Password: os.Getenv("REDIS_PASSWORD"),
+		DB:       int(redisDbInt),
+	})
+
+	cmd := rc.Ping(context.Background())
+
+	if cmd.Err() != nil {
+		return nil, fmt.Errorf("could not connect to Redis: %v", cmd.Err())
+	}
+	if cmd.Val() != "PONG" {
+		return nil, fmt.Errorf("unexpected response from Redis: %s", cmd.Val())
+	}
+
+	return &Redis{
+		client: rc,
+	}, nil
+}
+
+func (r *Redis) Get(key string) (string, error) {
+	cmd := r.client.Get(context.Background(), key)
+	if cmd.Err() != nil {
+		if errors.Is(cmd.Err(), redis.Nil) {
+			return "", nil // Key does not exist
+		}
+		return "", fmt.Errorf("could not get value for key %s: %v", key, cmd.Err())
+	}
+	return cmd.Val(), nil
+}
+
+func (r *Redis) Set(key string, value string, expiration time.Duration) error {
+	cmd := r.client.Set(context.Background(), key, value, expiration)
+	if cmd.Err() != nil {
+		return fmt.Errorf("could not set value for key %s: %v", key, cmd.Err())
+	}
+	if cmd.Val() != "OK" {
+		return fmt.Errorf("unexpected response from Redis when setting key %s: %s", key, cmd.Val())
+	}
+
+	return nil
+}
+
+func (r *Redis) Close() error {
+	if r.client == nil {
+		return nil
+	}
+	err := r.client.Close()
+	if err != nil {
+		return fmt.Errorf("could not close Redis client: %v", err)
+	}
+	return nil
+}
+
+func WithContext(ctx context.Context, r *Redis) context.Context {
+	return context.WithValue(ctx, redisKey, r)
+}
+
+func FromContext(ctx context.Context) (*Redis, error) {
+	r, ok := ctx.Value(redisKey).(*Redis)
+	if !ok {
+		return nil, errors.New("no Redis client found in context")
+	}
+	if r == nil {
+		return nil, errors.New("redis client is nil")
+	}
+	return r, nil
+}

resize/resize.go

@@ -0,0 +1,30 @@
+package resize
+
+import (
+	"bytes"
+	"fmt"
+	"github.com/nfnt/resize"
+	i "image"
+	"image/jpeg"
+	_ "image/png"
+)
+
+func Shrink(image string, maxSize uint, quality int) (string, error) {
+	if quality < 1 || quality > 100 {
+		return "", fmt.Errorf("quality must be between 1 and 100, got %d", quality)
+	}
+
+	img, _, err := i.Decode(bytes.NewReader([]byte(image)))
+	if err != nil {
+		return "", err
+	}
+
+	resizedImg := resize.Thumbnail(maxSize, maxSize, img, resize.Lanczos3)
+	var buffer bytes.Buffer
+	err = jpeg.Encode(&buffer, resizedImg, &jpeg.Options{Quality: quality})
+	if err != nil {
+		return "", err
+	}
+
+	return buffer.String(), nil
+}

resize/resize_test.go

@@ -0,0 +1,48 @@
+package resize
+
+import (
+	"bytes"
+	"image"
+	"image/color"
+	"image/jpeg"
+	"testing"
+)
+
+func createTestImage() []byte {
+	img := image.NewRGBA(image.Rect(0, 0, 100, 100))
+	for x := 0; x < 100; x++ {
+		for y := 0; y < 100; y++ {
+			img.Set(x, y, color.RGBA{uint8(x), uint8(y), 255, 255})
+		}
+	}
+	var buf bytes.Buffer
+	_ = jpeg.Encode(&buf, img, nil)
+	return buf.Bytes()
+}
+
+func TestShrink_Success(t *testing.T) {
+	testImage := createTestImage()
+	result, err := Shrink(string(testImage), 50, 80)
+	if err != nil {
+		t.Fatalf("expected no error, got %v", err)
+	}
+	if len(result) == 0 {
+		t.Fatalf("expected non-empty result, got empty string")
+	}
+}
+
+func TestShrink_InvalidImage(t *testing.T) {
+	invalidImage := "not-an-image"
+	_, err := Shrink(invalidImage, 50, 80)
+	if err == nil {
+		t.Fatalf("expected an error for invalid image input, got nil")
+	}
+}
+
+func TestShrink_InvalidQuality(t *testing.T) {
+	testImage := createTestImage()
+	_, err := Shrink(string(testImage), 50, -10)
+	if err == nil {
+		t.Fatalf("expected an error for invalid quality, got nil")
+	}
+}