Add basic unit tests

build.gradle

@@ -23,6 +23,8 @@ dependencies {
 	annotationProcessor 'org.projectlombok:lombok'
 	annotationProcessor "org.springframework.boot:spring-boot-configuration-processor"
 	implementation 'org.springframework.boot:spring-boot-starter-web'
+	implementation 'org.springframework.boot:spring-boot-starter-actuator'
+	implementation 'org.springframework.boot:spring-boot-starter-aop'
 	implementation group: 'com.google.guava', name: 'guava', version: '29.0-jre'
 	testImplementation('org.springframework.boot:spring-boot-starter-test') {
 		exclude group: 'org.junit.vintage', module: 'junit-vintage-engine'

src/main/java/au/com/tpic/avatar/services/AvatarService.java

 package au.com.tpic.avatar.services;
 
 import au.com.tpic.avatar.configuration.AvatarServiceProperites;
+import org.springframework.http.MediaType;
+import org.springframework.http.ResponseEntity;
 import org.springframework.stereotype.Service;
 import org.springframework.util.DigestUtils;
 
@@ -26,22 +28,24 @@ public class AvatarService {
     public AvatarService(AvatarServiceProperites properites) throws IOException {
         Stream<Path> avatars = Files.walk(properites.getDirectory());
         this.fileList = new HashMap<>();
-        avatars.filter(this::correctFormat).forEach(path -> this.fileList.put(getHash(path), path));
+        avatars.filter(this::correctFormat).forEach(path -> this.fileList.put(getFileHash(path), path));
     }
 
-    public byte[] getAvatar(String hash, String size) throws IOException {
+    public ResponseEntity<byte[]> getAvatar(String request, String size) throws IOException {
         try {
-            hash = hash.toLowerCase();
+            String hash = getRequestHash(request);
+            MediaType format = getRequestFormat(request);
             ByteArrayOutputStream baos = new ByteArrayOutputStream();
             BufferedImage image = (fileList.containsKey(hash)) ? readImageToSize(fileList.get(hash), Integer.parseInt(size)) : generateIdenticons(hash, Integer.parseInt(size));
-            ImageIO.write(image, "jpg", baos);
-            return baos.toByteArray();
+            ImageIO.write(image, format.getSubtype(), baos);
+            return ResponseEntity.ok().contentType(format).body(baos.toByteArray());
         } catch (Exception ignored) {
-            return getClass().getClassLoader().getResourceAsStream("default.jpg").readAllBytes();
+            byte[] body = getClass().getClassLoader().getResourceAsStream("default.jpg").readAllBytes();
+            return ResponseEntity.ok().contentType(MediaType.IMAGE_JPEG).body(body);
         }
     }
 
-    public static BufferedImage generateIdenticons(String text, int size) {
+    private static BufferedImage generateIdenticons(String text, int size) {
         int width = 5, height = 5;
 
         byte[] hash = text.getBytes();
@@ -50,7 +54,7 @@ public class AvatarService {
         WritableRaster raster = identicon.getRaster();
 
         int[] background = new int[]{255, 255, 255};
-        int[] foreground = new int[]{hash[0] & 255, hash[3] & 255, hash[6] & 255};
+        int[] foreground = new int[]{hash[0] & 255, hash[hash.length / 3] & 255, hash[hash.length / 2] & 255};
 
         for (int x = 0; x < width; x++) {
             //Enforce horizontal symmetry
@@ -86,7 +90,7 @@ public class AvatarService {
         return outputImage;
     }
 
-    private String getHash(Path path) {
+    private String getFileHash(Path path) {
         String filename = com.google.common.io.Files.getNameWithoutExtension(path.getFileName().toString());
         return DigestUtils.md5DigestAsHex(filename.getBytes());
     }
@@ -97,5 +101,17 @@ public class AvatarService {
         return accepted.contains(extension.toLowerCase());
     }
 
+    private String getRequestHash(String request) {
+        return request.toLowerCase().split("\\.")[0];
+    }
+
+    private MediaType getRequestFormat(String request) {
+        try {
+            String format = request.toLowerCase().split("\\.")[1];
+            return MediaType.valueOf("image/" + format);
+        } catch (Exception ignored) {
+            return MediaType.IMAGE_JPEG;
+        }
+    }
 
 }

src/main/java/au/com/tpic/avatar/web/AvatarController.java

@@ -2,7 +2,7 @@ package au.com.tpic.avatar.web;
 
 import au.com.tpic.avatar.services.AvatarService;
 import org.springframework.beans.factory.annotation.Autowired;
-import org.springframework.http.MediaType;
+import org.springframework.http.ResponseEntity;
 import org.springframework.web.bind.annotation.*;
 
 import java.io.IOException;
@@ -14,13 +14,13 @@ public class AvatarController {
     @Autowired
     private AvatarService service;
 
-    @GetMapping(produces = MediaType.IMAGE_JPEG_VALUE)
-    public byte[] getDefaultAvatar(@RequestParam(value = "s", required = false, defaultValue = "200") String size) throws IOException {
+    @GetMapping
+    public ResponseEntity<byte[]> getDefaultAvatar(@RequestParam(value = "s", required = false, defaultValue = "200") String size) throws IOException {
         return service.getAvatar(null, size);
     }
 
-    @GetMapping(value = "{hash}", produces = MediaType.IMAGE_JPEG_VALUE)
-    public byte[] getAvatar(@PathVariable String hash, @RequestParam(value = "s", required = false, defaultValue = "200") String size) throws IOException {
-        return service.getAvatar(hash, size);
+    @GetMapping(value = "{request}")
+    public ResponseEntity<byte[]> getAvatar(@PathVariable String request, @RequestParam(value = "s", required = false, defaultValue = "200") String size) throws IOException {
+        return service.getAvatar(request, size);
     }
 }

src/test/java/au/com/tpic/avatar/services/AvatarServiceTest.java

+package au.com.tpic.avatar.services;
+
+import au.com.tpic.avatar.configuration.AvatarServiceProperites;
+import org.junit.jupiter.api.Test;
+import org.springframework.http.MediaType;
+import org.springframework.http.ResponseEntity;
+
+import java.io.IOException;
+import java.nio.file.Path;
+
+import static org.assertj.core.api.Assertions.assertThat;
+
+
+class AvatarServiceTest {
+
+    private final AvatarService avatarService;
+
+    public AvatarServiceTest() throws IOException {
+        AvatarServiceProperites properties = new AvatarServiceProperites();
+        properties.setDirectory(Path.of("build", "tmp"));
+        this.avatarService = new AvatarService(properties);
+    }
+
+    @Test
+    void getDefaultAvatar() throws IOException {
+        byte[] expectedBody = getClass().getResourceAsStream("/default.jpg").readAllBytes();
+        ResponseEntity<byte[]> expectedResponse = ResponseEntity.ok().contentType(MediaType.IMAGE_JPEG).body(expectedBody);
+        assertThat(avatarService.getAvatar(null, "200")).isEqualTo(expectedResponse);
+    }
+
+    @Test
+    void getIdenticonAvatar() throws IOException {
+        byte[] expectedBody = getClass().getResourceAsStream("/B725DDDD5F2F979522DCC55A05E.jpg").readAllBytes();
+        ResponseEntity<byte[]> expectedResponse = ResponseEntity.ok().contentType(MediaType.IMAGE_JPEG).body(expectedBody);
+        assertThat(avatarService.getAvatar("B725DDDD5F2F979522DCC55A05E", "200")).isEqualTo(expectedResponse);
+    }
+
+}
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