Add Open Graph and Twitter Card meta-tags for link previews

Replace PathResourceResolver SPA fallback with SpaController that injects OG/Twitter meta-tags into cached index.html template. Event pages get event-specific tags (title, date, location), all other pages get generic fete branding. Includes og-image.png brand asset and forward-headers-strategy for proxy support. Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
2026-03-09 20:25:39 +01:00
parent fa34223c10
commit 751201617d
16 changed files with 1270 additions and 28 deletions
--- a/backend/src/test/java/de/fete/adapter/in/web/SpaControllerTest.java
+++ b/backend/src/test/java/de/fete/adapter/in/web/SpaControllerTest.java
@@ -0,0 +1,281 @@
+package de.fete.adapter.in.web;
+
+import static org.assertj.core.api.Assertions.assertThat;
+import static org.springframework.test.web.servlet.request.MockMvcRequestBuilders.get;
+import static org.springframework.test.web.servlet.result.MockMvcResultMatchers.content;
+import static org.springframework.test.web.servlet.result.MockMvcResultMatchers.status;
+
+import de.fete.TestcontainersConfig;
+import de.fete.adapter.out.persistence.EventJpaEntity;
+import de.fete.adapter.out.persistence.EventJpaRepository;
+import java.time.LocalDate;
+import java.time.OffsetDateTime;
+import java.time.ZoneOffset;
+import java.util.UUID;
+import org.junit.jupiter.api.Test;
+import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.boot.test.autoconfigure.web.servlet.AutoConfigureMockMvc;
+import org.springframework.boot.test.context.SpringBootTest;
+import org.springframework.context.annotation.Import;
+import org.springframework.http.MediaType;
+import org.springframework.test.web.servlet.MockMvc;
+
+@SpringBootTest
+@AutoConfigureMockMvc
+@Import(TestcontainersConfig.class)
+class SpaControllerTest {
+
+  @Autowired
+  private MockMvc mockMvc;
+
+  @Autowired
+  private EventJpaRepository eventJpaRepository;
+
+  // --- Phase 2: Base functionality ---
+
+  @Test
+  void rootServesHtml() throws Exception {
+    mockMvc.perform(get("/").accept(MediaType.TEXT_HTML))
+        .andExpect(status().isOk())
+        .andExpect(content().contentTypeCompatibleWith(MediaType.TEXT_HTML));
+  }
+
+  @Test
+  void rootHtmlDoesNotContainPlaceholder() throws Exception {
+    String html = mockMvc.perform(get("/").accept(MediaType.TEXT_HTML))
+        .andExpect(status().isOk())
+        .andReturn().getResponse().getContentAsString();
+
+    assertThat(html).doesNotContain("<!-- OG_META_TAGS -->");
+  }
+
+  @Test
+  void createRouteServesHtml() throws Exception {
+    mockMvc.perform(get("/create").accept(MediaType.TEXT_HTML))
+        .andExpect(status().isOk())
+        .andExpect(content().contentTypeCompatibleWith(MediaType.TEXT_HTML));
+  }
+
+  @Test
+  void eventsRouteServesHtml() throws Exception {
+    mockMvc.perform(get("/events").accept(MediaType.TEXT_HTML))
+        .andExpect(status().isOk())
+        .andExpect(content().contentTypeCompatibleWith(MediaType.TEXT_HTML));
+  }
+
+  // --- Phase 4 (US2): Generic OG meta-tags ---
+
+  @Test
+  void rootContainsGenericOgTitle() throws Exception {
+    String html = mockMvc.perform(get("/").accept(MediaType.TEXT_HTML))
+        .andExpect(status().isOk())
+        .andReturn().getResponse().getContentAsString();
+
+    assertThat(html).contains("og:title");
+    assertThat(html).contains("content=\"fete\"");
+  }
+
+  @Test
+  void createRouteContainsGenericOgDescription() throws Exception {
+    String html = mockMvc.perform(get("/create").accept(MediaType.TEXT_HTML))
+        .andExpect(status().isOk())
+        .andReturn().getResponse().getContentAsString();
+
+    assertThat(html).contains("og:description");
+    assertThat(html).contains("Privacy-focused event planning");
+  }
+
+  @Test
+  void unknownRouteReturns404() throws Exception {
+    mockMvc.perform(get("/unknown/path").accept(MediaType.TEXT_HTML))
+        .andExpect(status().isNotFound());
+  }
+
+  // --- Phase 5 (US3): Twitter Card meta-tags ---
+
+  @Test
+  void eventRouteContainsTwitterCardTags() throws Exception {
+    EventJpaEntity event = seedEvent(
+        "Twitter Test", "Testing cards",
+        "Europe/Berlin", "Berlin", LocalDate.now().plusDays(30));
+
+    String html = mockMvc.perform(
+            get("/events/" + event.getEventToken()).accept(MediaType.TEXT_HTML))
+        .andExpect(status().isOk())
+        .andReturn().getResponse().getContentAsString();
+
+    assertThat(html).contains("twitter:card");
+    assertThat(html).contains("twitter:title");
+    assertThat(html).contains("twitter:description");
+  }
+
+  @Test
+  void genericRouteContainsTwitterCardTags() throws Exception {
+    String html = mockMvc.perform(get("/").accept(MediaType.TEXT_HTML))
+        .andExpect(status().isOk())
+        .andReturn().getResponse().getContentAsString();
+
+    assertThat(html).contains("twitter:card");
+    assertThat(html).contains("content=\"summary\"");
+  }
+
+  // --- Phase 3 (US1): Event-specific OG meta-tags ---
+
+  @Test
+  void eventRouteContainsEventSpecificOgTitle() throws Exception {
+    EventJpaEntity event = seedEvent(
+        "Birthday Party", "Come celebrate!",
+        "Europe/Berlin", "Berlin", LocalDate.now().plusDays(30));
+
+    String html = mockMvc.perform(
+            get("/events/" + event.getEventToken()).accept(MediaType.TEXT_HTML))
+        .andExpect(status().isOk())
+        .andReturn().getResponse().getContentAsString();
+
+    assertThat(html).contains("og:title");
+    assertThat(html).contains("Birthday Party");
+  }
+
+  @Test
+  void eventRouteContainsOgDescription() throws Exception {
+    EventJpaEntity event = seedEvent(
+        "BBQ", "Bring drinks!",
+        "Europe/Berlin", "Central Park", LocalDate.now().plusDays(30));
+
+    String html = mockMvc.perform(
+            get("/events/" + event.getEventToken()).accept(MediaType.TEXT_HTML))
+        .andExpect(status().isOk())
+        .andReturn().getResponse().getContentAsString();
+
+    assertThat(html).contains("og:description");
+    assertThat(html).contains("Central Park");
+    assertThat(html).contains("Bring drinks!");
+  }
+
+  @Test
+  void eventRouteContainsOgUrl() throws Exception {
+    EventJpaEntity event = seedEvent(
+        "Party", null,
+        "Europe/Berlin", null, LocalDate.now().plusDays(30));
+
+    String html = mockMvc.perform(
+            get("/events/" + event.getEventToken()).accept(MediaType.TEXT_HTML))
+        .andExpect(status().isOk())
+        .andReturn().getResponse().getContentAsString();
+
+    assertThat(html).contains("og:url");
+    assertThat(html).contains("/events/" + event.getEventToken());
+  }
+
+  @Test
+  void eventRouteContainsOgImage() throws Exception {
+    EventJpaEntity event = seedEvent(
+        "Party", null,
+        "Europe/Berlin", null, LocalDate.now().plusDays(30));
+
+    String html = mockMvc.perform(
+            get("/events/" + event.getEventToken()).accept(MediaType.TEXT_HTML))
+        .andExpect(status().isOk())
+        .andReturn().getResponse().getContentAsString();
+
+    assertThat(html).contains("og:image");
+    assertThat(html).contains("/og-image.png");
+  }
+
+  @Test
+  void unknownEventTokenFallsBackToGenericMeta() throws Exception {
+    String html = mockMvc.perform(
+            get("/events/" + UUID.randomUUID()).accept(MediaType.TEXT_HTML))
+        .andExpect(status().isOk())
+        .andReturn().getResponse().getContentAsString();
+
+    assertThat(html).contains("og:title");
+    assertThat(html).contains("content=\"fete\"");
+  }
+
+  // --- HTML escaping ---
+
+  @Test
+  void specialCharactersAreHtmlEscaped() throws Exception {
+    EventJpaEntity event = seedEvent(
+        "Tom & Jerry's \"Party\"", "Fun <times> & more",
+        "Europe/Berlin", "O'Brien's Pub", LocalDate.now().plusDays(30));
+
+    String html = mockMvc.perform(
+            get("/events/" + event.getEventToken()).accept(MediaType.TEXT_HTML))
+        .andExpect(status().isOk())
+        .andReturn().getResponse().getContentAsString();
+
+    assertThat(html).contains("Tom &amp; Jerry");
+    assertThat(html).contains("&amp; more");
+    assertThat(html).contains("&lt;times&gt;");
+    assertThat(html).doesNotContain("content=\"Tom & Jerry");
+  }
+
+  // --- Title truncation ---
+
+  @Test
+  void longTitleIsTruncatedTo70Chars() throws Exception {
+    String longTitle = "A".repeat(80);
+    EventJpaEntity event = seedEvent(
+        longTitle, "Desc",
+        "Europe/Berlin", null, LocalDate.now().plusDays(30));
+
+    String html = mockMvc.perform(
+            get("/events/" + event.getEventToken()).accept(MediaType.TEXT_HTML))
+        .andExpect(status().isOk())
+        .andReturn().getResponse().getContentAsString();
+
+    assertThat(html).contains("A".repeat(67) + "...");
+    assertThat(html).doesNotContain("A".repeat(68));
+  }
+
+  // --- Description formatting ---
+
+  @Test
+  void eventWithoutLocationOmitsPinEmoji() throws Exception {
+    EventJpaEntity event = seedEvent(
+        "Online Meetup", "Virtual gathering",
+        "Europe/Berlin", null, LocalDate.now().plusDays(30));
+
+    String html = mockMvc.perform(
+            get("/events/" + event.getEventToken()).accept(MediaType.TEXT_HTML))
+        .andExpect(status().isOk())
+        .andReturn().getResponse().getContentAsString();
+
+    assertThat(html).doesNotContain("📍");
+  }
+
+  @Test
+  void eventWithoutDescriptionOmitsDash() throws Exception {
+    EventJpaEntity event = seedEvent(
+        "Silent Event", null,
+        "Europe/Berlin", "Berlin", LocalDate.now().plusDays(30));
+
+    String html = mockMvc.perform(
+            get("/events/" + event.getEventToken()).accept(MediaType.TEXT_HTML))
+        .andExpect(status().isOk())
+        .andReturn().getResponse().getContentAsString();
+
+    assertThat(html).contains("📅");
+    assertThat(html).contains("Berlin");
+    assertThat(html).doesNotContain(" — ");
+  }
+
+  private EventJpaEntity seedEvent(
+      String title, String description, String timezone,
+      String location, LocalDate expiryDate) {
+    var entity = new EventJpaEntity();
+    entity.setEventToken(UUID.randomUUID());
+    entity.setOrganizerToken(UUID.randomUUID());
+    entity.setTitle(title);
+    entity.setDescription(description);
+    entity.setDateTime(
+        OffsetDateTime.of(2026, 6, 15, 20, 0, 0, 0, ZoneOffset.ofHours(2)));
+    entity.setTimezone(timezone);
+    entity.setLocation(location);
+    entity.setExpiryDate(expiryDate);
+    entity.setCreatedAt(OffsetDateTime.now());
+    return eventJpaRepository.save(entity);
+  }
+}
--- a/backend/src/test/java/de/fete/config/WebConfigTest.java
+++ b/backend/src/test/java/de/fete/config/WebConfigTest.java
@@ -29,8 +29,10 @@ class WebConfigTest {

  @Test
  void apiPrefixNotAccessibleWithoutIt() throws Exception {
-    // /events without /api prefix should not resolve to the API endpoint
-    mockMvc.perform(get("/events"))
-        .andExpect(status().isNotFound());
+    // /events without /api prefix should not resolve to the REST API endpoint;
+    // it is served by SpaController as HTML instead
+    mockMvc.perform(get("/events")
+            .accept("text/html"))
+        .andExpect(status().isOk());
  }
 }
--- a/backend/src/test/resources/static/index.html
+++ b/backend/src/test/resources/static/index.html
@@ -0,0 +1,13 @@
+<!DOCTYPE html>
+<html lang="en">
+  <head>
+    <meta charset="UTF-8">
+    <meta name="viewport" content="width=device-width, initial-scale=1.0">
+    <link rel="icon" type="image/svg+xml" href="/favicon.svg">
+    <!-- OG_META_TAGS -->
+    <title>fete</title>
+  </head>
+  <body>
+    <div id="app"></div>
+  </body>
+</html>