CELDEV-1332 - Add the shared messages component and web overlay

celements-messages/component/pom.xml

@@ -0,0 +1,74 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/maven-v4_0_0.xsd">
+  <parent>
+    <groupId>com.celements</groupId>
+    <artifactId>celements-parent</artifactId>
+    <version>7.1-SNAPSHOT</version>
+  </parent>
+  <modelVersion>4.0.0</modelVersion>
+  <artifactId>celements-messages</artifactId>
+  <version>7.2-SNAPSHOT</version>
+  <description>Celements Messages</description>
+  <dependencies>
+    <dependency>
+      <groupId>com.celements</groupId>
+      <artifactId>celements-core</artifactId>
+      <scope>provided</scope>
+    </dependency>
+    <dependency>
+      <groupId>com.celements</groupId>
+      <artifactId>celements-model</artifactId>
+      <scope>provided</scope>
+    </dependency>
+    <dependency>
+      <groupId>com.celements</groupId>
+      <artifactId>celements-spring-security</artifactId>
+      <scope>provided</scope>
+    </dependency>
+    <dependency>
+      <groupId>com.celements</groupId>
+      <artifactId>celements-xwiki-velocity</artifactId>
+      <scope>provided</scope>
+    </dependency>
+    <dependency>
+      <groupId>com.celements</groupId>
+      <artifactId>celements-xwiki-core</artifactId>
+      <scope>provided</scope>
+    </dependency>
+    <dependency>
+      <groupId>org.springframework</groupId>
+      <artifactId>spring-web</artifactId>
+      <scope>provided</scope>
+    </dependency>
+    <dependency>
+      <groupId>org.xwiki.platform</groupId>
+      <artifactId>xwiki-core-script</artifactId>
+      <scope>provided</scope>
+    </dependency>
+    <dependency>
+      <groupId>javax.inject</groupId>
+      <artifactId>javax.inject</artifactId>
+    </dependency>
+    <dependency>
+      <groupId>javax.servlet</groupId>
+      <artifactId>javax.servlet-api</artifactId>
+      <scope>provided</scope>
+    </dependency>
+    <dependency>
+      <groupId>com.celements</groupId>
+      <artifactId>celements-shared-tests</artifactId>
+      <scope>test</scope>
+    </dependency>
+    <dependency>
+      <groupId>com.celements</groupId>
+      <artifactId>celements-subsystem-migration-manager</artifactId>
+      <scope>test</scope>
+    </dependency>
+  </dependencies>
+  <scm>
+    <connection>scm:git:git@github.com:celements/celements-features.git</connection>
+    <developerConnection>scm:git:git@github.com:celements/celements-features.git</developerConnection>
+    <url>https://github.com/celements/celements-features</url>
+    <tag>HEAD</tag>
+  </scm>
+</project>

celements-messages/component/src/main/java/com/celements/messages/api/MessagesController.java

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+package com.celements.messages.api;
+
+import java.io.IOException;
+
+import javax.inject.Inject;
+
+import org.apache.velocity.VelocityContext;
+import org.springframework.http.MediaType;
+import org.springframework.security.access.prepost.PreAuthorize;
+import org.springframework.web.bind.annotation.GetMapping;
+import org.springframework.web.bind.annotation.RequestMapping;
+import org.springframework.web.bind.annotation.RestController;
+import org.xwiki.velocity.VelocityManager;
+import org.xwiki.velocity.XWikiVelocityException;
+
+import com.celements.messages.service.MessageService;
+import com.celements.spring.security.AuthenticatedBaseController;
+import com.celements.web.service.IPrepareVelocityContext;
+
+@RestController
+@RequestMapping("/v1/messages")
+@PreAuthorize("permitAll()")
+public class MessagesController extends AuthenticatedBaseController {
+
+  private static final String JSON_MEDIA_TYPE = MediaType.APPLICATION_JSON_VALUE + ";charset=UTF-8";
+
+  private final VelocityManager velocityManager;
+  private final IPrepareVelocityContext prepareVelocityContext;
+  private final MessageService messageService;
+
+  @Inject
+  public MessagesController(VelocityManager velocityManager,
+      IPrepareVelocityContext prepareVelocityContext, MessageService messageService) {
+    this.velocityManager = velocityManager;
+    this.prepareVelocityContext = prepareVelocityContext;
+    this.messageService = messageService;
+  }
+
+  @GetMapping(produces = JSON_MEDIA_TYPE)
+  public String getMessages() throws IOException, XWikiVelocityException {
+    return messageService.getMessages(getPreparedVelocityContext());
+  }
+
+  @GetMapping(value = "/validation", produces = JSON_MEDIA_TYPE)
+  public String getValidationMessages() throws IOException, XWikiVelocityException {
+    return messageService.getValidationMessages(getPreparedVelocityContext());
+  }
+
+  private VelocityContext getPreparedVelocityContext() {
+    checkAuth();
+    VelocityContext velocityContext = velocityManager.getVelocityContext();
+    prepareVelocityContext.prepareVelocityContext(velocityContext);
+    return velocityContext;
+  }
+}

celements-messages/component/src/main/java/com/celements/messages/script/MessagesScriptService.java

@@ -0,0 +1,35 @@
+package com.celements.messages.script;
+
+import java.io.IOException;
+
+import javax.inject.Inject;
+
+import org.springframework.stereotype.Component;
+import org.xwiki.script.service.ScriptService;
+import org.xwiki.velocity.VelocityManager;
+import org.xwiki.velocity.XWikiVelocityException;
+
+import com.celements.messages.service.MessageService;
+
+@Component(MessagesScriptService.NAME)
+public class MessagesScriptService implements ScriptService {
+
+  public static final String NAME = "celementsMessages";
+
+  private final VelocityManager velocityManager;
+  private final MessageService messageService;
+
+  @Inject
+  public MessagesScriptService(VelocityManager velocityManager, MessageService messageService) {
+    this.velocityManager = velocityManager;
+    this.messageService = messageService;
+  }
+
+  public String getMessages() throws IOException, XWikiVelocityException {
+    return messageService.getMessages(velocityManager.getVelocityContext());
+  }
+
+  public String getValidationMessages() throws IOException, XWikiVelocityException {
+    return messageService.getValidationMessages(velocityManager.getVelocityContext());
+  }
+}

celements-messages/component/src/main/java/com/celements/messages/service/MessageService.java

@@ -0,0 +1,124 @@
+package com.celements.messages.service;
+
+import java.io.IOException;
+import java.io.InputStream;
+import java.io.StringWriter;
+import java.nio.charset.StandardCharsets;
+import java.util.Collections;
+import java.util.List;
+import java.util.Optional;
+
+import javax.inject.Inject;
+import javax.servlet.ServletContext;
+
+import org.apache.velocity.VelocityContext;
+import org.springframework.stereotype.Component;
+import org.xwiki.velocity.VelocityEngine;
+import org.xwiki.velocity.VelocityManager;
+import org.xwiki.velocity.XWikiVelocityException;
+
+import com.celements.sajson.JsonBuilder;
+
+@Component
+public class MessageService {
+
+  static final String GENERAL_FRAGMENT_DIRECTORY = "/templates/celMessages/general/";
+  static final String VALIDATION_FRAGMENT_DIRECTORY = "/templates/celMessages/validation/";
+  private static final String REQUIRED_FRAGMENT_NAME = "celements.vm";
+  private static final String JSON_BUILDER_CONTEXT_KEY = "jsonBuilder";
+
+  private final ServletContext servletContext;
+  private final VelocityManager velocityManager;
+
+  @Inject
+  public MessageService(ServletContext servletContext, VelocityManager velocityManager) {
+    this.servletContext = servletContext;
+    this.velocityManager = velocityManager;
+  }
+
+  public String getMessages(VelocityContext velocityContext)
+      throws IOException, XWikiVelocityException {
+    return renderFragments(GENERAL_FRAGMENT_DIRECTORY, velocityContext);
+  }
+
+  public String getValidationMessages(VelocityContext velocityContext)
+      throws IOException, XWikiVelocityException {
+    return renderFragments(VALIDATION_FRAGMENT_DIRECTORY, velocityContext);
+  }
+
+  private String renderFragments(String directory, VelocityContext velocityContext)
+      throws IOException, XWikiVelocityException {
+    var jsonBuilder = new JsonBuilder();
+    jsonBuilder.openDictionary();
+    List<String> fragments = discoverFragments(directory);
+    requireBaseFragment(directory, fragments);
+    boolean hadJsonBuilder = velocityContext.containsKey(JSON_BUILDER_CONTEXT_KEY);
+    Object previousJsonBuilder = velocityContext.get(JSON_BUILDER_CONTEXT_KEY);
+    velocityContext.put(JSON_BUILDER_CONTEXT_KEY, jsonBuilder);
+    try {
+      VelocityEngine velocityEngine = velocityManager.getVelocityEngine();
+      for (String fragment : fragments) {
+        evaluateFragment(velocityEngine, velocityContext, jsonBuilder, fragment);
+      }
+      jsonBuilder.closeDictionary();
+      if (!jsonBuilder.isComplete()) {
+        throw new IllegalStateException("Messages JSON builder is incomplete");
+      }
+      return jsonBuilder.getJSON();
+    } finally {
+      if (hadJsonBuilder) {
+        velocityContext.put(JSON_BUILDER_CONTEXT_KEY, previousJsonBuilder);
+      } else {
+        velocityContext.remove(JSON_BUILDER_CONTEXT_KEY);
+      }
+    }
+  }
+
+  private List<String> discoverFragments(String directory) {
+    return Optional.ofNullable(servletContext.getResourcePaths(directory))
+        .orElseGet(Collections::emptySet)
+        .stream()
+        .filter(path -> isDirectFragment(directory, path))
+        .sorted()
+        .toList();
+  }
+
+  private boolean isDirectFragment(String directory, String path) {
+    return path.startsWith(directory) && path.endsWith(".vm")
+        && !path.substring(directory.length()).contains("/");
+  }
+
+  private void requireBaseFragment(String directory, List<String> fragments) throws IOException {
+    String requiredFragment = directory + REQUIRED_FRAGMENT_NAME;
+    if (!fragments.contains(requiredFragment)) {
+      throw new IOException("Required message fragment not found: " + requiredFragment);
+    }
+  }
+
+  private void evaluateFragment(VelocityEngine velocityEngine, VelocityContext velocityContext,
+      JsonBuilder jsonBuilder, String fragment) throws IOException, XWikiVelocityException {
+    int initialDepth = jsonBuilder.getOpenCommandCount();
+    var writer = new StringWriter();
+    boolean evaluated = velocityEngine.evaluate(velocityContext, writer, fragment,
+        getFragmentContent(fragment));
+    if (!evaluated) {
+      throw new XWikiVelocityException("Failed to evaluate message fragment: " + fragment);
+    }
+    if (!writer.toString().trim().isEmpty()) {
+      throw new IOException("Message fragment emitted response content: " + fragment);
+    }
+    if (jsonBuilder.getOpenCommandCount() != initialDepth) {
+      throw new IllegalStateException(
+          "Message fragment left an unbalanced JSON builder: " + fragment);
+    }
+  }
+
+  private String getFragmentContent(String fragment) throws IOException {
+    try (InputStream stream = servletContext.getResourceAsStream(fragment)) {
+      if (stream == null) {
+        throw new IOException("Message fragment not found: " + fragment);
+      }
+      return new String(stream.readAllBytes(), StandardCharsets.UTF_8);
+    }
+  }
+}