Server-Port über SERVER_PORT aus der .env konfigurierbar

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

.dockerignore

@@ -0,0 +1,14 @@
+# Zugangsdaten duerfen nicht ins Image
+.env
+
+# Build-Artefakte und generierte Dateien — nur das fertige JAR darf ins Image
+target/*
+!target/pdf-tool-*.jar
+node_modules/
+src/main/frontend/generated/
+
+# Repository und IDE
+.git/
+.github/
+.vscode/
+.DS_Store

.env.example

@@ -3,3 +3,6 @@
 
 # MongoDB-Verbindung fuer die Rechnungstemplates
 MONGODB_URI=mongodb://BENUTZER:PASSWORT@localhost:27017/pdf-tool?authSource=admin
+
+# HTTP-Port der Anwendung (Standard: 8083)
+SERVER_PORT=8083

.mvn/wrapper/maven-wrapper.properties

@@ -0,0 +1,3 @@
+wrapperVersion=3.3.4
+distributionType=only-script
+distributionUrl=https://repo.maven.apache.org/maven2/org/apache/maven/apache-maven/3.9.11/apache-maven-3.9.11-bin.zip

Dockerfile

@@ -0,0 +1,12 @@
+FROM eclipse-temurin:21-jre
+
+ARG JAR_FILE=target/*.jar
+
+# Zeitzone auf Berlin setzen und 24h-Format konfigurieren
+ENV TZ=Europe/Berlin
+ENV LC_TIME=de_DE.UTF-8
+RUN ln -snf /usr/share/zoneinfo/$TZ /etc/localtime && echo $TZ > /etc/timezone
+
+COPY ${JAR_FILE} app.jar
+EXPOSE 8083
+ENTRYPOINT ["java", "-jar", "/app.jar", "--spring.profiles.active=production"]

README.md

@@ -25,7 +25,7 @@ Open-Source-Referenzimplementierung von ZUGFeRD, inklusive des Mustang-Validator
 mvn spring-boot:run
 ```
 
-Die Weboberfläche ist dann unter <http://localhost:8080> erreichbar:
+Die Weboberfläche ist dann unter <http://localhost:8083> erreichbar:
 PDF hochladen, Rechnungsdaten ausfüllen, "E-Rechnung erzeugen" klicken, ZIP herunterladen.
 
 Produktions-Build:
@@ -62,14 +62,14 @@ Factur-X-XML). Antwort: der Mustang-Prüfbericht als XML — HTTP 200 bei gülti
 HTTP 422 bei ungültiger Rechnung, ebenfalls mit `X-Zugferd-Valid`-Header.
 
 ```bash
-curl -X POST http://localhost:8080/api/invoices/validate \
+curl -X POST http://localhost:8083/api/invoices/validate \
   -F "file=@rechnung-zugferd.pdf"
 ```
 
 ### Beispiel
 
 ```bash
-curl -X POST http://localhost:8080/api/invoices/sign \
+curl -X POST http://localhost:8083/api/invoices/sign \
   -F "file=@rechnung.pdf" \
   -F "metadata=@metadata.json;type=application/json" \
   -o rechnung-zugferd.zip

docker_push.sh

@@ -0,0 +1,85 @@
+#!/usr/bin/env bash
+
+set -euo pipefail
+
+readonly SCRIPT_DIR="$(CDPATH= cd -- "$(dirname -- "${BASH_SOURCE[0]}")" && pwd)"
+readonly REGISTRY_IMAGE="registry.assecutor.org/ait"
+readonly BACKEND_DIR="${SCRIPT_DIR}"
+
+usage() {
+  cat <<'EOF'
+Verwendung:
+  ./docker_push.sh [x.y.z]
+
+Beispiel:
+  ./docker_push.sh 0.9.13
+  ./docker_push.sh
+
+Voraussetzungen:
+  - Docker Buildx ist installiert
+  - Login zur Registry wurde bereits ausgeführt:
+    docker login registry.assecutor.org
+
+Ohne Versionsargument wird automatisch die Version aus der pom.xml verwendet.
+EOF
+}
+
+fail() {
+  echo "Fehler: $*" >&2
+  exit 1
+}
+
+require_command() {
+  command -v "$1" >/dev/null 2>&1 || fail "'$1' wurde nicht gefunden."
+}
+
+resolve_pom_version() {
+  [[ -x "${BACKEND_DIR}/mvnw" ]] || fail "'${BACKEND_DIR}/mvnw' wurde nicht gefunden oder ist nicht ausführbar."
+
+  local version
+  version="$(
+    cd "${BACKEND_DIR}" && ./mvnw -q -DforceStdout help:evaluate -Dexpression=project.version \
+      | awk 'NF { last = $0 } END { print last }'
+  )"
+
+  [[ -n "${version}" ]] || fail "Version konnte nicht aus der pom.xml ermittelt werden."
+  echo "${version}"
+}
+
+# Version aus der pom.xml bestimmt den JAR-Namen; ein optionales Argument
+# überschreibt nur den Image-Tag.
+POM_VERSION="$(resolve_pom_version)"
+VERSION="${1:-${POM_VERSION}}"
+
+if [[ "${VERSION}" == "-h" || "${VERSION}" == "--help" ]]; then
+  usage
+  exit 0
+fi
+
+if [[ ! "${VERSION}" =~ ^[0-9]+\.[0-9]+\.[0-9]+$ ]]; then
+  fail "Versionsnummer muss das Format x.y.z haben."
+fi
+
+require_command docker
+docker buildx version >/dev/null 2>&1 || fail "Docker Buildx ist nicht verfügbar."
+
+cd "${SCRIPT_DIR}"
+
+echo "Verwende Release-Version ${VERSION}."
+echo "Baue Production-JAR für Version ${VERSION} ..."
+(cd "${BACKEND_DIR}" && ./mvnw -Pproduction -DskipTests package)
+
+JAR_FILE_REL="target/pdf-tool-${POM_VERSION}.jar"
+JAR_FILE_ABS="${BACKEND_DIR}/${JAR_FILE_REL}"
+[[ -f "${JAR_FILE_ABS}" ]] || fail "Release-JAR wurde nicht gefunden: ${JAR_FILE_ABS}"
+
+echo "Pushe Image ${REGISTRY_IMAGE}:${VERSION} ..."
+docker buildx build \
+  --platform linux/amd64 \
+  -f "${BACKEND_DIR}/Dockerfile" \
+  --build-arg "JAR_FILE=${JAR_FILE_REL}" \
+  -t "${REGISTRY_IMAGE}:${VERSION}" \
+  --push \
+  "${BACKEND_DIR}"
+
+echo "Fertig: ${REGISTRY_IMAGE}:${VERSION}"

mvnw

@@ -0,0 +1,295 @@
+#!/bin/sh
+# ----------------------------------------------------------------------------
+# Licensed to the Apache Software Foundation (ASF) under one
+# or more contributor license agreements.  See the NOTICE file
+# distributed with this work for additional information
+# regarding copyright ownership.  The ASF licenses this file
+# to you under the Apache License, Version 2.0 (the
+# "License"); you may not use this file except in compliance
+# with the License.  You may obtain a copy of the License at
+#
+#    http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing,
+# software distributed under the License is distributed on an
+# "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+# KIND, either express or implied.  See the License for the
+# specific language governing permissions and limitations
+# under the License.
+# ----------------------------------------------------------------------------
+
+# ----------------------------------------------------------------------------
+# Apache Maven Wrapper startup batch script, version 3.3.4
+#
+# Optional ENV vars
+# -----------------
+#   JAVA_HOME - location of a JDK home dir, required when download maven via java source
+#   MVNW_REPOURL - repo url base for downloading maven distribution
+#   MVNW_USERNAME/MVNW_PASSWORD - user and password for downloading maven
+#   MVNW_VERBOSE - true: enable verbose log; debug: trace the mvnw script; others: silence the output
+# ----------------------------------------------------------------------------
+
+set -euf
+[ "${MVNW_VERBOSE-}" != debug ] || set -x
+
+# OS specific support.
+native_path() { printf %s\\n "$1"; }
+case "$(uname)" in
+CYGWIN* | MINGW*)
+  [ -z "${JAVA_HOME-}" ] || JAVA_HOME="$(cygpath --unix "$JAVA_HOME")"
+  native_path() { cygpath --path --windows "$1"; }
+  ;;
+esac
+
+# set JAVACMD and JAVACCMD
+set_java_home() {
+  # For Cygwin and MinGW, ensure paths are in Unix format before anything is touched
+  if [ -n "${JAVA_HOME-}" ]; then
+    if [ -x "$JAVA_HOME/jre/sh/java" ]; then
+      # IBM's JDK on AIX uses strange locations for the executables
+      JAVACMD="$JAVA_HOME/jre/sh/java"
+      JAVACCMD="$JAVA_HOME/jre/sh/javac"
+    else
+      JAVACMD="$JAVA_HOME/bin/java"
+      JAVACCMD="$JAVA_HOME/bin/javac"
+
+      if [ ! -x "$JAVACMD" ] || [ ! -x "$JAVACCMD" ]; then
+        echo "The JAVA_HOME environment variable is not defined correctly, so mvnw cannot run." >&2
+        echo "JAVA_HOME is set to \"$JAVA_HOME\", but \"\$JAVA_HOME/bin/java\" or \"\$JAVA_HOME/bin/javac\" does not exist." >&2
+        return 1
+      fi
+    fi
+  else
+    JAVACMD="$(
+      'set' +e
+      'unset' -f command 2>/dev/null
+      'command' -v java
+    )" || :
+    JAVACCMD="$(
+      'set' +e
+      'unset' -f command 2>/dev/null
+      'command' -v javac
+    )" || :
+
+    if [ ! -x "${JAVACMD-}" ] || [ ! -x "${JAVACCMD-}" ]; then
+      echo "The java/javac command does not exist in PATH nor is JAVA_HOME set, so mvnw cannot run." >&2
+      return 1
+    fi
+  fi
+}
+
+# hash string like Java String::hashCode
+hash_string() {
+  str="${1:-}" h=0
+  while [ -n "$str" ]; do
+    char="${str%"${str#?}"}"
+    h=$(((h * 31 + $(LC_CTYPE=C printf %d "'$char")) % 4294967296))
+    str="${str#?}"
+  done
+  printf %x\\n $h
+}
+
+verbose() { :; }
+[ "${MVNW_VERBOSE-}" != true ] || verbose() { printf %s\\n "${1-}"; }
+
+die() {
+  printf %s\\n "$1" >&2
+  exit 1
+}
+
+trim() {
+  # MWRAPPER-139:
+  #   Trims trailing and leading whitespace, carriage returns, tabs, and linefeeds.
+  #   Needed for removing poorly interpreted newline sequences when running in more
+  #   exotic environments such as mingw bash on Windows.
+  printf "%s" "${1}" | tr -d '[:space:]'
+}
+
+scriptDir="$(dirname "$0")"
+scriptName="$(basename "$0")"
+
+# parse distributionUrl and optional distributionSha256Sum, requires .mvn/wrapper/maven-wrapper.properties
+while IFS="=" read -r key value; do
+  case "${key-}" in
+  distributionUrl) distributionUrl=$(trim "${value-}") ;;
+  distributionSha256Sum) distributionSha256Sum=$(trim "${value-}") ;;
+  esac
+done <"$scriptDir/.mvn/wrapper/maven-wrapper.properties"
+[ -n "${distributionUrl-}" ] || die "cannot read distributionUrl property in $scriptDir/.mvn/wrapper/maven-wrapper.properties"
+
+case "${distributionUrl##*/}" in
+maven-mvnd-*bin.*)
+  MVN_CMD=mvnd.sh _MVNW_REPO_PATTERN=/maven/mvnd/
+  case "${PROCESSOR_ARCHITECTURE-}${PROCESSOR_ARCHITEW6432-}:$(uname -a)" in
+  *AMD64:CYGWIN* | *AMD64:MINGW*) distributionPlatform=windows-amd64 ;;
+  :Darwin*x86_64) distributionPlatform=darwin-amd64 ;;
+  :Darwin*arm64) distributionPlatform=darwin-aarch64 ;;
+  :Linux*x86_64*) distributionPlatform=linux-amd64 ;;
+  *)
+    echo "Cannot detect native platform for mvnd on $(uname)-$(uname -m), use pure java version" >&2
+    distributionPlatform=linux-amd64
+    ;;
+  esac
+  distributionUrl="${distributionUrl%-bin.*}-$distributionPlatform.zip"
+  ;;
+maven-mvnd-*) MVN_CMD=mvnd.sh _MVNW_REPO_PATTERN=/maven/mvnd/ ;;
+*) MVN_CMD="mvn${scriptName#mvnw}" _MVNW_REPO_PATTERN=/org/apache/maven/ ;;
+esac
+
+# apply MVNW_REPOURL and calculate MAVEN_HOME
+# maven home pattern: ~/.m2/wrapper/dists/{apache-maven-<version>,maven-mvnd-<version>-<platform>}/<hash>
+[ -z "${MVNW_REPOURL-}" ] || distributionUrl="$MVNW_REPOURL$_MVNW_REPO_PATTERN${distributionUrl#*"$_MVNW_REPO_PATTERN"}"
+distributionUrlName="${distributionUrl##*/}"
+distributionUrlNameMain="${distributionUrlName%.*}"
+distributionUrlNameMain="${distributionUrlNameMain%-bin}"
+MAVEN_USER_HOME="${MAVEN_USER_HOME:-${HOME}/.m2}"
+MAVEN_HOME="${MAVEN_USER_HOME}/wrapper/dists/${distributionUrlNameMain-}/$(hash_string "$distributionUrl")"
+
+exec_maven() {
+  unset MVNW_VERBOSE MVNW_USERNAME MVNW_PASSWORD MVNW_REPOURL || :
+  exec "$MAVEN_HOME/bin/$MVN_CMD" "$@" || die "cannot exec $MAVEN_HOME/bin/$MVN_CMD"
+}
+
+if [ -d "$MAVEN_HOME" ]; then
+  verbose "found existing MAVEN_HOME at $MAVEN_HOME"
+  exec_maven "$@"
+fi
+
+case "${distributionUrl-}" in
+*?-bin.zip | *?maven-mvnd-?*-?*.zip) ;;
+*) die "distributionUrl is not valid, must match *-bin.zip or maven-mvnd-*.zip, but found '${distributionUrl-}'" ;;
+esac
+
+# prepare tmp dir
+if TMP_DOWNLOAD_DIR="$(mktemp -d)" && [ -d "$TMP_DOWNLOAD_DIR" ]; then
+  clean() { rm -rf -- "$TMP_DOWNLOAD_DIR"; }
+  trap clean HUP INT TERM EXIT
+else
+  die "cannot create temp dir"
+fi
+
+mkdir -p -- "${MAVEN_HOME%/*}"
+
+# Download and Install Apache Maven
+verbose "Couldn't find MAVEN_HOME, downloading and installing it ..."
+verbose "Downloading from: $distributionUrl"
+verbose "Downloading to: $TMP_DOWNLOAD_DIR/$distributionUrlName"
+
+# select .zip or .tar.gz
+if ! command -v unzip >/dev/null; then
+  distributionUrl="${distributionUrl%.zip}.tar.gz"
+  distributionUrlName="${distributionUrl##*/}"
+fi
+
+# verbose opt
+__MVNW_QUIET_WGET=--quiet __MVNW_QUIET_CURL=--silent __MVNW_QUIET_UNZIP=-q __MVNW_QUIET_TAR=''
+[ "${MVNW_VERBOSE-}" != true ] || __MVNW_QUIET_WGET='' __MVNW_QUIET_CURL='' __MVNW_QUIET_UNZIP='' __MVNW_QUIET_TAR=v
+
+# normalize http auth
+case "${MVNW_PASSWORD:+has-password}" in
+'') MVNW_USERNAME='' MVNW_PASSWORD='' ;;
+has-password) [ -n "${MVNW_USERNAME-}" ] || MVNW_USERNAME='' MVNW_PASSWORD='' ;;
+esac
+
+if [ -z "${MVNW_USERNAME-}" ] && command -v wget >/dev/null; then
+  verbose "Found wget ... using wget"
+  wget ${__MVNW_QUIET_WGET:+"$__MVNW_QUIET_WGET"} "$distributionUrl" -O "$TMP_DOWNLOAD_DIR/$distributionUrlName" || die "wget: Failed to fetch $distributionUrl"
+elif [ -z "${MVNW_USERNAME-}" ] && command -v curl >/dev/null; then
+  verbose "Found curl ... using curl"
+  curl ${__MVNW_QUIET_CURL:+"$__MVNW_QUIET_CURL"} -f -L -o "$TMP_DOWNLOAD_DIR/$distributionUrlName" "$distributionUrl" || die "curl: Failed to fetch $distributionUrl"
+elif set_java_home; then
+  verbose "Falling back to use Java to download"
+  javaSource="$TMP_DOWNLOAD_DIR/Downloader.java"
+  targetZip="$TMP_DOWNLOAD_DIR/$distributionUrlName"
+  cat >"$javaSource" <<-END
+	public class Downloader extends java.net.Authenticator
+	{
+	  protected java.net.PasswordAuthentication getPasswordAuthentication()
+	  {
+	    return new java.net.PasswordAuthentication( System.getenv( "MVNW_USERNAME" ), System.getenv( "MVNW_PASSWORD" ).toCharArray() );
+	  }
+	  public static void main( String[] args ) throws Exception
+	  {
+	    setDefault( new Downloader() );
+	    java.nio.file.Files.copy( java.net.URI.create( args[0] ).toURL().openStream(), java.nio.file.Paths.get( args[1] ).toAbsolutePath().normalize() );
+	  }
+	}
+	END
+  # For Cygwin/MinGW, switch paths to Windows format before running javac and java
+  verbose " - Compiling Downloader.java ..."
+  "$(native_path "$JAVACCMD")" "$(native_path "$javaSource")" || die "Failed to compile Downloader.java"
+  verbose " - Running Downloader.java ..."
+  "$(native_path "$JAVACMD")" -cp "$(native_path "$TMP_DOWNLOAD_DIR")" Downloader "$distributionUrl" "$(native_path "$targetZip")"
+fi
+
+# If specified, validate the SHA-256 sum of the Maven distribution zip file
+if [ -n "${distributionSha256Sum-}" ]; then
+  distributionSha256Result=false
+  if [ "$MVN_CMD" = mvnd.sh ]; then
+    echo "Checksum validation is not supported for maven-mvnd." >&2
+    echo "Please disable validation by removing 'distributionSha256Sum' from your maven-wrapper.properties." >&2
+    exit 1
+  elif command -v sha256sum >/dev/null; then
+    if echo "$distributionSha256Sum  $TMP_DOWNLOAD_DIR/$distributionUrlName" | sha256sum -c - >/dev/null 2>&1; then
+      distributionSha256Result=true
+    fi
+  elif command -v shasum >/dev/null; then
+    if echo "$distributionSha256Sum  $TMP_DOWNLOAD_DIR/$distributionUrlName" | shasum -a 256 -c >/dev/null 2>&1; then
+      distributionSha256Result=true
+    fi
+  else
+    echo "Checksum validation was requested but neither 'sha256sum' or 'shasum' are available." >&2
+    echo "Please install either command, or disable validation by removing 'distributionSha256Sum' from your maven-wrapper.properties." >&2
+    exit 1
+  fi
+  if [ $distributionSha256Result = false ]; then
+    echo "Error: Failed to validate Maven distribution SHA-256, your Maven distribution might be compromised." >&2
+    echo "If you updated your Maven version, you need to update the specified distributionSha256Sum property." >&2
+    exit 1
+  fi
+fi
+
+# unzip and move
+if command -v unzip >/dev/null; then
+  unzip ${__MVNW_QUIET_UNZIP:+"$__MVNW_QUIET_UNZIP"} "$TMP_DOWNLOAD_DIR/$distributionUrlName" -d "$TMP_DOWNLOAD_DIR" || die "failed to unzip"
+else
+  tar xzf${__MVNW_QUIET_TAR:+"$__MVNW_QUIET_TAR"} "$TMP_DOWNLOAD_DIR/$distributionUrlName" -C "$TMP_DOWNLOAD_DIR" || die "failed to untar"
+fi
+
+# Find the actual extracted directory name (handles snapshots where filename != directory name)
+actualDistributionDir=""
+
+# First try the expected directory name (for regular distributions)
+if [ -d "$TMP_DOWNLOAD_DIR/$distributionUrlNameMain" ]; then
+  if [ -f "$TMP_DOWNLOAD_DIR/$distributionUrlNameMain/bin/$MVN_CMD" ]; then
+    actualDistributionDir="$distributionUrlNameMain"
+  fi
+fi
+
+# If not found, search for any directory with the Maven executable (for snapshots)
+if [ -z "$actualDistributionDir" ]; then
+  # enable globbing to iterate over items
+  set +f
+  for dir in "$TMP_DOWNLOAD_DIR"/*; do
+    if [ -d "$dir" ]; then
+      if [ -f "$dir/bin/$MVN_CMD" ]; then
+        actualDistributionDir="$(basename "$dir")"
+        break
+      fi
+    fi
+  done
+  set -f
+fi
+
+if [ -z "$actualDistributionDir" ]; then
+  verbose "Contents of $TMP_DOWNLOAD_DIR:"
+  verbose "$(ls -la "$TMP_DOWNLOAD_DIR")"
+  die "Could not find Maven distribution directory in extracted archive"
+fi
+
+verbose "Found extracted Maven distribution directory: $actualDistributionDir"
+printf %s\\n "$distributionUrl" >"$TMP_DOWNLOAD_DIR/$actualDistributionDir/mvnw.url"
+mv -- "$TMP_DOWNLOAD_DIR/$actualDistributionDir" "$MAVEN_HOME" || [ -d "$MAVEN_HOME" ] || die "fail to move MAVEN_HOME"
+
+clean || :
+exec_maven "$@"

mvnw.cmd

@@ -0,0 +1,189 @@
+<# : batch portion
+@REM ----------------------------------------------------------------------------
+@REM Licensed to the Apache Software Foundation (ASF) under one
+@REM or more contributor license agreements.  See the NOTICE file
+@REM distributed with this work for additional information
+@REM regarding copyright ownership.  The ASF licenses this file
+@REM to you under the Apache License, Version 2.0 (the
+@REM "License"); you may not use this file except in compliance
+@REM with the License.  You may obtain a copy of the License at
+@REM
+@REM    http://www.apache.org/licenses/LICENSE-2.0
+@REM
+@REM Unless required by applicable law or agreed to in writing,
+@REM software distributed under the License is distributed on an
+@REM "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+@REM KIND, either express or implied.  See the License for the
+@REM specific language governing permissions and limitations
+@REM under the License.
+@REM ----------------------------------------------------------------------------
+
+@REM ----------------------------------------------------------------------------
+@REM Apache Maven Wrapper startup batch script, version 3.3.4
+@REM
+@REM Optional ENV vars
+@REM   MVNW_REPOURL - repo url base for downloading maven distribution
+@REM   MVNW_USERNAME/MVNW_PASSWORD - user and password for downloading maven
+@REM   MVNW_VERBOSE - true: enable verbose log; others: silence the output
+@REM ----------------------------------------------------------------------------
+
+@IF "%__MVNW_ARG0_NAME__%"=="" (SET __MVNW_ARG0_NAME__=%~nx0)
+@SET __MVNW_CMD__=
+@SET __MVNW_ERROR__=
+@SET __MVNW_PSMODULEP_SAVE=%PSModulePath%
+@SET PSModulePath=
+@FOR /F "usebackq tokens=1* delims==" %%A IN (`powershell -noprofile "& {$scriptDir='%~dp0'; $script='%__MVNW_ARG0_NAME__%'; icm -ScriptBlock ([Scriptblock]::Create((Get-Content -Raw '%~f0'))) -NoNewScope}"`) DO @(
+  IF "%%A"=="MVN_CMD" (set __MVNW_CMD__=%%B) ELSE IF "%%B"=="" (echo %%A) ELSE (echo %%A=%%B)
+)
+@SET PSModulePath=%__MVNW_PSMODULEP_SAVE%
+@SET __MVNW_PSMODULEP_SAVE=
+@SET __MVNW_ARG0_NAME__=
+@SET MVNW_USERNAME=
+@SET MVNW_PASSWORD=
+@IF NOT "%__MVNW_CMD__%"=="" ("%__MVNW_CMD__%" %*)
+@echo Cannot start maven from wrapper >&2 && exit /b 1
+@GOTO :EOF
+: end batch / begin powershell #>
+
+$ErrorActionPreference = "Stop"
+if ($env:MVNW_VERBOSE -eq "true") {
+  $VerbosePreference = "Continue"
+}
+
+# calculate distributionUrl, requires .mvn/wrapper/maven-wrapper.properties
+$distributionUrl = (Get-Content -Raw "$scriptDir/.mvn/wrapper/maven-wrapper.properties" | ConvertFrom-StringData).distributionUrl
+if (!$distributionUrl) {
+  Write-Error "cannot read distributionUrl property in $scriptDir/.mvn/wrapper/maven-wrapper.properties"
+}
+
+switch -wildcard -casesensitive ( $($distributionUrl -replace '^.*/','') ) {
+  "maven-mvnd-*" {
+    $USE_MVND = $true
+    $distributionUrl = $distributionUrl -replace '-bin\.[^.]*$',"-windows-amd64.zip"
+    $MVN_CMD = "mvnd.cmd"
+    break
+  }
+  default {
+    $USE_MVND = $false
+    $MVN_CMD = $script -replace '^mvnw','mvn'
+    break
+  }
+}
+
+# apply MVNW_REPOURL and calculate MAVEN_HOME
+# maven home pattern: ~/.m2/wrapper/dists/{apache-maven-<version>,maven-mvnd-<version>-<platform>}/<hash>
+if ($env:MVNW_REPOURL) {
+  $MVNW_REPO_PATTERN = if ($USE_MVND -eq $False) { "/org/apache/maven/" } else { "/maven/mvnd/" }
+  $distributionUrl = "$env:MVNW_REPOURL$MVNW_REPO_PATTERN$($distributionUrl -replace "^.*$MVNW_REPO_PATTERN",'')"
+}
+$distributionUrlName = $distributionUrl -replace '^.*/',''
+$distributionUrlNameMain = $distributionUrlName -replace '\.[^.]*$','' -replace '-bin$',''
+
+$MAVEN_M2_PATH = "$HOME/.m2"
+if ($env:MAVEN_USER_HOME) {
+  $MAVEN_M2_PATH = "$env:MAVEN_USER_HOME"
+}
+
+if (-not (Test-Path -Path $MAVEN_M2_PATH)) {
+    New-Item -Path $MAVEN_M2_PATH -ItemType Directory | Out-Null
+}
+
+$MAVEN_WRAPPER_DISTS = $null
+if ((Get-Item $MAVEN_M2_PATH).Target[0] -eq $null) {
+  $MAVEN_WRAPPER_DISTS = "$MAVEN_M2_PATH/wrapper/dists"
+} else {
+  $MAVEN_WRAPPER_DISTS = (Get-Item $MAVEN_M2_PATH).Target[0] + "/wrapper/dists"
+}
+
+$MAVEN_HOME_PARENT = "$MAVEN_WRAPPER_DISTS/$distributionUrlNameMain"
+$MAVEN_HOME_NAME = ([System.Security.Cryptography.SHA256]::Create().ComputeHash([byte[]][char[]]$distributionUrl) | ForEach-Object {$_.ToString("x2")}) -join ''
+$MAVEN_HOME = "$MAVEN_HOME_PARENT/$MAVEN_HOME_NAME"
+
+if (Test-Path -Path "$MAVEN_HOME" -PathType Container) {
+  Write-Verbose "found existing MAVEN_HOME at $MAVEN_HOME"
+  Write-Output "MVN_CMD=$MAVEN_HOME/bin/$MVN_CMD"
+  exit $?
+}
+
+if (! $distributionUrlNameMain -or ($distributionUrlName -eq $distributionUrlNameMain)) {
+  Write-Error "distributionUrl is not valid, must end with *-bin.zip, but found $distributionUrl"
+}
+
+# prepare tmp dir
+$TMP_DOWNLOAD_DIR_HOLDER = New-TemporaryFile
+$TMP_DOWNLOAD_DIR = New-Item -Itemtype Directory -Path "$TMP_DOWNLOAD_DIR_HOLDER.dir"
+$TMP_DOWNLOAD_DIR_HOLDER.Delete() | Out-Null
+trap {
+  if ($TMP_DOWNLOAD_DIR.Exists) {
+    try { Remove-Item $TMP_DOWNLOAD_DIR -Recurse -Force | Out-Null }
+    catch { Write-Warning "Cannot remove $TMP_DOWNLOAD_DIR" }
+  }
+}
+
+New-Item -Itemtype Directory -Path "$MAVEN_HOME_PARENT" -Force | Out-Null
+
+# Download and Install Apache Maven
+Write-Verbose "Couldn't find MAVEN_HOME, downloading and installing it ..."
+Write-Verbose "Downloading from: $distributionUrl"
+Write-Verbose "Downloading to: $TMP_DOWNLOAD_DIR/$distributionUrlName"
+
+$webclient = New-Object System.Net.WebClient
+if ($env:MVNW_USERNAME -and $env:MVNW_PASSWORD) {
+  $webclient.Credentials = New-Object System.Net.NetworkCredential($env:MVNW_USERNAME, $env:MVNW_PASSWORD)
+}
+[Net.ServicePointManager]::SecurityProtocol = [Net.SecurityProtocolType]::Tls12
+$webclient.DownloadFile($distributionUrl, "$TMP_DOWNLOAD_DIR/$distributionUrlName") | Out-Null
+
+# If specified, validate the SHA-256 sum of the Maven distribution zip file
+$distributionSha256Sum = (Get-Content -Raw "$scriptDir/.mvn/wrapper/maven-wrapper.properties" | ConvertFrom-StringData).distributionSha256Sum
+if ($distributionSha256Sum) {
+  if ($USE_MVND) {
+    Write-Error "Checksum validation is not supported for maven-mvnd. `nPlease disable validation by removing 'distributionSha256Sum' from your maven-wrapper.properties."
+  }
+  Import-Module $PSHOME\Modules\Microsoft.PowerShell.Utility -Function Get-FileHash
+  if ((Get-FileHash "$TMP_DOWNLOAD_DIR/$distributionUrlName" -Algorithm SHA256).Hash.ToLower() -ne $distributionSha256Sum) {
+    Write-Error "Error: Failed to validate Maven distribution SHA-256, your Maven distribution might be compromised. If you updated your Maven version, you need to update the specified distributionSha256Sum property."
+  }
+}
+
+# unzip and move
+Expand-Archive "$TMP_DOWNLOAD_DIR/$distributionUrlName" -DestinationPath "$TMP_DOWNLOAD_DIR" | Out-Null
+
+# Find the actual extracted directory name (handles snapshots where filename != directory name)
+$actualDistributionDir = ""
+
+# First try the expected directory name (for regular distributions)
+$expectedPath = Join-Path "$TMP_DOWNLOAD_DIR" "$distributionUrlNameMain"
+$expectedMvnPath = Join-Path "$expectedPath" "bin/$MVN_CMD"
+if ((Test-Path -Path $expectedPath -PathType Container) -and (Test-Path -Path $expectedMvnPath -PathType Leaf)) {
+  $actualDistributionDir = $distributionUrlNameMain
+}
+
+# If not found, search for any directory with the Maven executable (for snapshots)
+if (!$actualDistributionDir) {
+  Get-ChildItem -Path "$TMP_DOWNLOAD_DIR" -Directory | ForEach-Object {
+    $testPath = Join-Path $_.FullName "bin/$MVN_CMD"
+    if (Test-Path -Path $testPath -PathType Leaf) {
+      $actualDistributionDir = $_.Name
+    }
+  }
+}
+
+if (!$actualDistributionDir) {
+  Write-Error "Could not find Maven distribution directory in extracted archive"
+}
+
+Write-Verbose "Found extracted Maven distribution directory: $actualDistributionDir"
+Rename-Item -Path "$TMP_DOWNLOAD_DIR/$actualDistributionDir" -NewName $MAVEN_HOME_NAME | Out-Null
+try {
+  Move-Item -Path "$TMP_DOWNLOAD_DIR/$MAVEN_HOME_NAME" -Destination $MAVEN_HOME_PARENT | Out-Null
+} catch {
+  if (! (Test-Path -Path "$MAVEN_HOME" -PathType Container)) {
+    Write-Error "fail to move MAVEN_HOME"
+  }
+} finally {
+  try { Remove-Item $TMP_DOWNLOAD_DIR -Recurse -Force | Out-Null }
+  catch { Write-Warning "Cannot remove $TMP_DOWNLOAD_DIR" }
+}
+
+Write-Output "MVN_CMD=$MAVEN_HOME/bin/$MVN_CMD"

pom.xml

@@ -13,9 +13,9 @@
 
     <groupId>de.assecutor</groupId>
     <artifactId>pdf-tool</artifactId>
-    <version>1.0.0-SNAPSHOT</version>
+    <version>0.9.0</version>
     <name>pdf-tool</name>
-    <description>ZUGFeRD E-Rechnungs-Konverter (PDF zu PDF/A-3 mit eingebettetem EN16931-XML)</description>
+    <description>AIT</description>
 
     <properties>
         <java.version>21</java.version>

src/main/java/de/assecutor/pdftool/api/InvoiceSigningController.java

@@ -29,12 +29,12 @@ import java.util.stream.Collectors;
  * REST-API zur Erzeugung und Prüfung rechtskonformer ZUGFeRD-E-Rechnungen.
  *
  * <pre>
- * curl -X POST http://localhost:8080/api/invoices/sign \
+ * curl -X POST http://localhost:8083/api/invoices/sign \
  *   -F "file=@rechnung.pdf" \
  *   -F "metadata=@metadata.json;type=application/json" \
  *   -o rechnung-zugferd.zip
  *
- * curl -X POST http://localhost:8080/api/invoices/validate \
+ * curl -X POST http://localhost:8083/api/invoices/validate \
  *   -F "file=@rechnung-zugferd.pdf"
  * </pre>
  */

src/main/java/de/assecutor/pdftool/template/MongoConnectionCheck.java

@@ -1,12 +1,15 @@
 package de.assecutor.pdftool.template;
 
+import de.assecutor.pdftool.invoice.InvoiceDraft;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 import org.springframework.boot.ApplicationArguments;
 import org.springframework.boot.ApplicationRunner;
 import org.springframework.boot.autoconfigure.mongo.MongoClientSettingsBuilderCustomizer;
 import org.springframework.context.annotation.Bean;
+import org.springframework.data.domain.Sort;
 import org.springframework.data.mongodb.core.MongoTemplate;
+import org.springframework.data.mongodb.core.index.Index;
 import org.springframework.stereotype.Component;
 
 import java.util.concurrent.TimeUnit;
@@ -15,6 +18,12 @@ import java.util.concurrent.TimeUnit;
  * Prüft beim Start die Verbindung zum MongoDB-Server und bricht den Start ab,
  * wenn er nicht erreichbar ist — die Anwendung setzt die Datenbank zwingend
  * voraus. Konfiguriert wird die Verbindung über MONGODB_URI in der .env-Datei.
+ *
+ * <p>Nach erfolgreicher Prüfung werden die Unique-Indizes auf die Template-
+ * bzw. Vorbelegungs-Namen sichergestellt (Spring legt Indizes aus
+ * {@code @Indexed} nicht automatisch an; auto-index-creation bleibt bewusst
+ * aus, damit ein nicht erreichbarer Server zuerst diese klare Fehlermeldung
+ * liefert).</p>
  */
 @Component
 public class MongoConnectionCheck implements ApplicationRunner {
@@ -38,6 +47,14 @@ public class MongoConnectionCheck implements ApplicationRunner {
                     "Keine Verbindung zum MongoDB-Server. Die Anwendung benötigt die Datenbank zwingend — "
                             + "bitte MONGODB_URI in der .env-Datei prüfen. Ursache: " + e.getMessage(), e);
         }
+        ensureUniqueNameIndexes();
+    }
+
+    /** Stellt sicher, dass Template- und Vorbelegungs-Namen in der Datenbank eindeutig sind. */
+    private void ensureUniqueNameIndexes() {
+        Index uniqueName = new Index().on("name", Sort.Direction.ASC).unique();
+        mongoTemplate.indexOps(InvoiceTemplate.class).createIndex(uniqueName);
+        mongoTemplate.indexOps(InvoiceDraft.class).createIndex(uniqueName);
     }
 
     /** Kurzer Auswahl-Timeout, damit ein nicht erreichbarer Server den Start schnell abbricht. */

src/main/java/de/assecutor/pdftool/ui/AddressBookView.java

@@ -36,6 +36,8 @@ import java.util.Optional;
 @PageTitle("Adressbuch")
 public class AddressBookView extends VerticalLayout {
 
+    private static final String EMAIL_PATTERN = "^[^@\\s]+@[^@\\s]+\\.[^@\\s]+$";
+
     private final AddressRepository repository;
 
     private final Grid<Address> grid = new Grid<>(Address.class, false);
@@ -142,6 +144,13 @@ public class AddressBookView extends VerticalLayout {
         vatId.setHelperText("z. B. DE261094748");
         EmailField email = new EmailField("E-Mail");
         email.setValue(target.getEmail() != null ? target.getEmail() : "");
+        // E-Mail direkt beim Verlassen des Feldes prüfen
+        email.addValueChangeListener(event -> {
+            String value = event.getValue();
+            boolean valid = value == null || value.isBlank() || value.matches(EMAIL_PATTERN);
+            email.setErrorMessage("Gültige E-Mail-Adresse angeben.");
+            email.setInvalid(!valid);
+        });
         TextField phone = new TextField("Telefon");
         phone.setValue(target.getPhone() != null ? target.getPhone() : "");
 
@@ -175,7 +184,7 @@ public class AddressBookView extends VerticalLayout {
                     errors.add(vatError.get());
                 }
             }
-            if (!email.getValue().isBlank() && !email.getValue().matches("^[^@\\s]+@[^@\\s]+\\.[^@\\s]+$")) {
+            if (!email.getValue().isBlank() && !email.getValue().matches(EMAIL_PATTERN)) {
                 email.setErrorMessage("Gültige E-Mail-Adresse angeben.");
                 email.setInvalid(true);
                 errors.add("E-Mail-Adresse ist ungültig.");

src/main/java/de/assecutor/pdftool/ui/MainLayout.java

@@ -4,12 +4,14 @@ import com.vaadin.flow.component.applayout.AppLayout;
 import com.vaadin.flow.component.applayout.DrawerToggle;
 import com.vaadin.flow.component.html.H1;
 import com.vaadin.flow.component.html.H2;
+import com.vaadin.flow.component.html.Span;
 import com.vaadin.flow.component.icon.VaadinIcon;
 import com.vaadin.flow.component.orderedlayout.Scroller;
 import com.vaadin.flow.component.sidenav.SideNav;
 import com.vaadin.flow.component.sidenav.SideNavItem;
 import com.vaadin.flow.router.PageTitle;
 import com.vaadin.flow.theme.lumo.LumoUtility;
+import org.springframework.beans.factory.annotation.Value;
 
 /**
  * Rahmenlayout der Anwendung mit linker Sidebar: Navigation zwischen der
@@ -22,13 +24,28 @@ public class MainLayout extends AppLayout {
     /** Titel der aktiven Seite in der Navbar. */
     private final H2 viewTitle = new H2();
 
-    public MainLayout() {
+    public MainLayout(@Value("${pdftool.version:}") String version) {
         setPrimarySection(Section.DRAWER);
 
-        H1 appName = new H1("AIT");
+        H1 appName = new H1();
+        appName.add(new Span("AIT"));
+        if (!version.isBlank()) {
+            Span versionLabel = new Span("(" + version + ")");
+            // Absolut positioniert an ihrer natürlichen Stelle rechts neben "AIT":
+            // die Version nimmt keinen Platz im Layout ein, "AIT" bleibt exakt mittig.
+            versionLabel.getStyle()
+                    .set("font-size", "var(--lumo-font-size-s)")
+                    .set("font-weight", "normal")
+                    .set("color", "var(--lumo-secondary-text-color)")
+                    .set("position", "absolute")
+                    .set("margin-left", "0.3em")
+                    // unten an der Schriftlinie von "AIT" ausrichten
+                    .set("bottom", "0.2em");
+            appName.add(versionLabel);
+        }
         appName.addClassNames(LumoUtility.FontSize.LARGE, LumoUtility.Margin.Vertical.MEDIUM);
         appName.setWidth("100%");
-        appName.getStyle().set("text-align", "center");
+        appName.getStyle().set("text-align", "center").set("position", "relative");
 
         SideNav nav = new SideNav();
         nav.addItem(new SideNavItem("E-Rechnung erzeugen", MainView.class, VaadinIcon.INVOICE.create()));

src/main/java/de/assecutor/pdftool/ui/MainView.java

@@ -87,7 +87,17 @@ public class MainView extends VerticalLayout {
     private final InvoiceDraftService invoiceDraftService;
 
     /** Laden zuvor gespeicherter Eingaben dieser Maske. */
-    private final ComboBox<String> draftSelect = new ComboBox<>("Gespeicherte Eingaben");
+    private final ComboBox<String> draftSelect = new ComboBox<>("Vorbelegung laden");
+
+    private final Button saveDraftButton = new Button("Eingaben speichern", event -> openSaveDraftDialog());
+
+    /**
+     * Formularstand zum Zeitpunkt des letzten Ladens bzw. Speicherns einer
+     * Vorbelegung; {@code null}, solange keine geladen wurde. Der
+     * Speichern-Button ist nur aktiv, wenn keine Vorbelegung geladen ist oder
+     * sich die Eingaben seither geändert haben.
+     */
+    private InvoiceDraft loadedDraftState;
 
     private final Button generate = new Button("E-Rechnung erzeugen", event -> generate());
 
@@ -135,18 +145,18 @@ public class MainView extends VerticalLayout {
                 + "und als ZIP-Datei bereitgestellt."));
 
         // Eingaben unter einem Namen speichern bzw. gespeicherte Eingaben laden.
-        draftSelect.setPlaceholder("Eingaben laden");
+        draftSelect.setPlaceholder("Vorbelegung laden");
         draftSelect.setClearButtonVisible(true);
         draftSelect.setWidth("300px");
         draftSelect.addValueChangeListener(event -> {
             if (event.isFromClient() && event.getValue() != null) {
                 loadDraft(event.getValue());
+            } else if (event.isFromClient()) {
+                loadedDraftState = null;
+                updateSaveDraftEnabled();
             }
         });
-        Button saveDraft = new Button("Eingaben speichern", event -> openSaveDraftDialog());
-        HorizontalLayout draftBar = new HorizontalLayout(draftSelect, saveDraft);
-        draftBar.setAlignItems(Alignment.END);
-        add(draftBar);
+        add(draftSelect);
 
         Upload upload = new Upload(uploadBuffer);
         upload.setAcceptedFileTypes("application/pdf", ".pdf");
@@ -226,7 +236,10 @@ public class MainView extends VerticalLayout {
         downloadLink.getElement().setAttribute("download", true);
         downloadLink.setVisible(false);
 
-        add(new HorizontalLayout(generate, downloadLink));
+        add(new HorizontalLayout(generate, saveDraftButton, downloadLink));
+
+        registerDraftDirtyTracking();
+        updateSaveDraftEnabled();
 
         if (environment.acceptsProfiles(Profiles.of("dev"))) {
             prefillDevData();
@@ -249,8 +262,6 @@ public class MainView extends VerticalLayout {
         dialog.setHeaderTitle("Eingaben speichern");
 
         TextField nameField = new TextField("Name");
-        nameField.setValue(draftSelect.getValue() != null ? draftSelect.getValue()
-                : invoiceNumber.getValue().trim());
         nameField.setWidth("300px");
         dialog.add(nameField);
 
@@ -291,9 +302,17 @@ public class MainView extends VerticalLayout {
     }
 
     private void saveDraft(String name) {
-        invoiceDraftService.save(buildDraft(name));
+        try {
+            invoiceDraftService.save(buildDraft(name));
+        } catch (Exception ex) {
+            showErrors(List.of("Die Eingaben konnten nicht unter \"" + name
+                    + "\" gespeichert werden: " + ex.getMessage()));
+            return;
+        }
         draftSelect.setItems(invoiceDraftService.names());
         draftSelect.setValue(name);
+        loadedDraftState = comparableState();
+        updateSaveDraftEnabled();
         Notification.show("Eingaben \"" + name + "\" gespeichert.", 3000, Notification.Position.BOTTOM_START)
                 .addThemeVariants(NotificationVariant.LUMO_SUCCESS);
     }
@@ -350,6 +369,9 @@ public class MainView extends VerticalLayout {
         }
         refreshItemsGrid();
         updateControlsEnabled();
+        // Frisch geladen: Speichern erst wieder anbieten, wenn sich etwas ändert.
+        loadedDraftState = comparableState();
+        updateSaveDraftEnabled();
     }
 
     private void applyParty(PartyForm form, InvoiceMetadata.Party party) {
@@ -438,6 +460,47 @@ public class MainView extends VerticalLayout {
 
     private void refreshItemsGrid() {
         itemsGrid.setItems(List.copyOf(lineItems));
+        updateSaveDraftEnabled();
+    }
+
+    /** Aktualisiert den Speichern-Button bei jeder Änderung an den Eingabefeldern. */
+    private void registerDraftDirtyTracking() {
+        invoiceNumber.addValueChangeListener(event -> updateSaveDraftEnabled());
+        issueDate.addValueChangeListener(event -> updateSaveDraftEnabled());
+        deliveryDate.addValueChangeListener(event -> updateSaveDraftEnabled());
+        dueDate.addValueChangeListener(event -> updateSaveDraftEnabled());
+        currency.addValueChangeListener(event -> updateSaveDraftEnabled());
+        paymentTerms.addValueChangeListener(event -> updateSaveDraftEnabled());
+        buyerReference.addValueChangeListener(event -> updateSaveDraftEnabled());
+        iban.addValueChangeListener(event -> updateSaveDraftEnabled());
+        bic.addValueChangeListener(event -> updateSaveDraftEnabled());
+        templateSelect.addValueChangeListener(event -> updateSaveDraftEnabled());
+        sender.onAnyChange(this::updateSaveDraftEnabled);
+        recipient.onAnyChange(this::updateSaveDraftEnabled);
+    }
+
+    /**
+     * Der Speichern-Button ist nur aktiv, wenn keine Vorbelegung geladen wurde
+     * oder sich die Eingaben seit dem Laden bzw. Speichern geändert haben.
+     */
+    private void updateSaveDraftEnabled() {
+        saveDraftButton.setEnabled(loadedDraftState == null || !comparableState().equals(loadedDraftState));
+    }
+
+    /** Der aktuelle Formularstand ohne Name und Zeitstempel, zum Vergleich mit der geladenen Vorbelegung. */
+    private InvoiceDraft comparableState() {
+        return new InvoiceDraft(null, "",
+                templateSelect.getValue(),
+                invoiceNumber.getValue().trim(),
+                issueDate.getValue(), deliveryDate.getValue(), dueDate.getValue(),
+                currency.getValue().trim(),
+                paymentTerms.getValue(),
+                buyerReference.getValue().trim(),
+                iban.getValue().trim(),
+                bic.getValue().trim(),
+                sender.toParty(), recipient.toParty(),
+                List.copyOf(lineItems),
+                null);
     }
 
     /** Dialog zum Anlegen ({@code existing == null}) bzw. Bearbeiten einer Rechnungsposition. */
@@ -729,6 +792,8 @@ public class MainView extends VerticalLayout {
      */
     private static class PartyForm extends FormLayout {
 
+        static final String EMAIL_PATTERN = "^[^@\\s]+@[^@\\s]+\\.[^@\\s]+$";
+
         private final boolean vatRequired;
         private final TextField name = new TextField("Firma / Name");
         private final TextField street = new TextField("Straße und Hausnummer");
@@ -757,6 +822,8 @@ public class MainView extends VerticalLayout {
             // Elektronische Adresse (BT-34/BT-49) ist nach PEPPOL-EN16931 Pflicht
             email.setRequiredIndicatorVisible(true);
             email.setErrorMessage("Gültige E-Mail-Adresse angeben.");
+            // E-Mail direkt beim Verlassen des Feldes prüfen
+            email.addValueChangeListener(event -> checkEmail());
             if (vatRequired) {
                 phone.setHelperText("Für den Verkäufer-Kontakt (BR-DE-6) empfohlen");
             }
@@ -776,6 +843,18 @@ public class MainView extends VerticalLayout {
             phone.setValue(phoneValue);
         }
 
+        /** Meldet jede Wertänderung eines Feldes, z. B. für die Dirty-Erkennung. */
+        void onAnyChange(Runnable listener) {
+            name.addValueChangeListener(event -> listener.run());
+            street.addValueChangeListener(event -> listener.run());
+            zip.addValueChangeListener(event -> listener.run());
+            city.addValueChangeListener(event -> listener.run());
+            countryCode.addValueChangeListener(event -> listener.run());
+            vatId.addValueChangeListener(event -> listener.run());
+            email.addValueChangeListener(event -> listener.run());
+            phone.addValueChangeListener(event -> listener.run());
+        }
+
         /** Leert alle Felder; das Land behält den Standardwert "DE". */
         void clearFields() {
             prefill("", "", "", "", "DE", "", "", "");
@@ -788,6 +867,19 @@ public class MainView extends VerticalLayout {
             email.setInvalid(false);
         }
 
+        /** @return true, wenn die E-Mail-Adresse gültig (oder leer) ist. */
+        private boolean checkEmail() {
+            String value = email.getValue();
+            if (value == null || value.isBlank()) {
+                email.setInvalid(false);
+                return true;
+            }
+            boolean valid = value.matches(EMAIL_PATTERN);
+            email.setErrorMessage("Gültige E-Mail-Adresse angeben.");
+            email.setInvalid(!valid);
+            return valid;
+        }
+
         /** @return true, wenn die USt-IdNr. gültig (oder leer) ist. */
         private boolean checkVatId() {
             String value = vatId.getValue();
@@ -820,12 +912,8 @@ public class MainView extends VerticalLayout {
                 email.setErrorMessage(partyLabel + ": E-Mail ist ein Pflichtfeld.");
                 email.setInvalid(true);
                 errors.add(partyLabel + ": E-Mail ist ein Pflichtfeld (elektronische Adresse der E-Rechnung).");
-            } else if (!email.getValue().matches("^[^@\\s]+@[^@\\s]+\\.[^@\\s]+$")) {
-                email.setErrorMessage("Gültige E-Mail-Adresse angeben.");
-                email.setInvalid(true);
+            } else if (!checkEmail()) {
                 errors.add(partyLabel + ": E-Mail-Adresse ist ungültig.");
-            } else {
-                email.setInvalid(false);
             }
             return errors;
         }

src/main/resources/application.properties

@@ -1,5 +1,8 @@
 spring.application.name=pdf-tool
-server.port=8080
+server.port=${SERVER_PORT:8083}
+
+# Wird beim Build durch die Version aus der pom.xml ersetzt (Resource-Filtering)
+pdftool.version=@project.version@
 
 spring.servlet.multipart.max-file-size=25MB
 spring.servlet.multipart.max-request-size=30MB