Add support TextAvatar feature and _avatar returns it.

src/main/scala/gitbucket/core/controller/AccountController.scala

@@ -21,13 +21,13 @@ import java.util.Date
 class AccountController extends AccountControllerBase
   with AccountService with RepositoryService with ActivityService with WikiService with LabelsService with SshKeyService
   with OneselfAuthenticator with UsersAuthenticator with GroupManagerAuthenticator with ReadableUsersAuthenticator
-  with AccessTokenService with WebHookService with RepositoryCreationService
+  with AccessTokenService with WebHookService with RepositoryCreationService with TextAvatarService
 
 
 trait AccountControllerBase extends AccountManagementControllerBase {
   self: AccountService with RepositoryService with ActivityService with WikiService with LabelsService with SshKeyService
     with OneselfAuthenticator with UsersAuthenticator with GroupManagerAuthenticator with ReadableUsersAuthenticator
-    with AccessTokenService with WebHookService with RepositoryCreationService =>
+    with AccessTokenService with WebHookService with RepositoryCreationService with TextAvatarService =>
 
   case class AccountNewForm(userName: String, password: String, fullName: String, mailAddress: String,
                             description: Option[String], url: Option[String], fileId: Option[String])
@@ -150,17 +150,17 @@ trait AccountControllerBase extends AccountManagementControllerBase {
 
   get("/:userName/_avatar"){
     val userName = params("userName")
-    (for {
-      account <- getAccountByUserName(userName)
-      image <- account.image
-    } yield (account, image)) match {
-      case Some((account, image)) =>
+    getAccountByUserName(userName).map{ account =>
+      account.image.map{ image =>
         response.setDateHeader("Last-Modified", account.updatedDate.getTime)
         RawData(FileUtil.getMimeType(image), new java.io.File(getUserUploadDir(userName), image))
-      case None =>
+      }.getOrElse{
         contentType = "image/png"
-        response.setDateHeader("Last-Modified", (new Date(0)).getTime)
-        Thread.currentThread.getContextClassLoader.getResourceAsStream("noimage.png")
+        response.setDateHeader("Last-Modified", new Date(0).getTime())
+        textAvatar(account.fullName)
+      }
+    }.getOrElse{
+      NotFound()
     }
   }
 

src/main/scala/gitbucket/core/service/TextAvatarService.scala

@@ -0,0 +1,49 @@
+package gitbucket.core.service
+
+import java.io.ByteArrayOutputStream
+import java.awt.image.BufferedImage
+import javax.imageio.ImageIO
+import java.awt.{Color, Font, RenderingHints}
+import java.awt.font.{FontRenderContext, TextLayout}
+import gitbucket.core.util.StringUtil
+
+trait TextAvatarService {
+  def textAvatar(nameText: String): Array[Byte] = {
+    val drawText = nameText.substring(0, 1)
+    val md5 = StringUtil.md5(nameText)
+    val hashedInt = Integer.parseInt(md5.substring(0, 2), 16)
+
+    val h = hashedInt / 256f
+    val bgColor = Color.getHSBColor(h, 1f, 1f)
+    val fgColor = Color.getHSBColor(h + 0.5f, 1f, 0.8f)
+
+    val size = (200, 200)
+    val canvas = new BufferedImage(size._1, size._2, BufferedImage.TYPE_INT_ARGB)
+    val g = canvas.createGraphics()
+
+    g.setColor(new Color(0, 0, 0, 0))
+    g.fillRect(0, 0, canvas.getWidth, canvas.getHeight)
+    g.setColor(bgColor)
+    g.fillRoundRect(0, 0, canvas.getWidth, canvas.getHeight, 60, 60)
+
+    g.setRenderingHint(RenderingHints.KEY_ANTIALIASING, RenderingHints.VALUE_ANTIALIAS_ON)
+
+    g.setColor(fgColor)
+    val font = new Font("SansSerif", Font.PLAIN, 180)
+    val context = g.getFontRenderContext
+    val txt = new TextLayout(drawText, font, context)
+    val bounds = txt.getBounds
+
+    val x: Int = ((size._1 - bounds.getWidth) / 2 - bounds.getX).toInt
+    val y: Int = ((size._2 - bounds.getHeight) / 2 - bounds.getY).toInt
+
+    g.setFont(font)
+    g.drawString(drawText, x, y)
+
+    g.dispose()
+
+    val stream = new ByteArrayOutputStream
+    ImageIO.write(canvas, "png", stream)
+    stream.toByteArray
+  }
+}