From 93f49f1fb3109c2e0d5f427cd2494eaa97e80f04 Mon Sep 17 00:00:00 2001
From: Viktor Lofgren <vlofgren@marginalia.nu>
Date: Thu, 17 Aug 2023 17:42:31 +0200
Subject: [PATCH] (search-service) RSS feed for the news feed

---
 .../nu/marginalia/search/SearchService.java   |  1 +
 .../search/svc/SearchFrontPageService.java    | 40 +++++++++++++++++++
 .../templates/search/index/index-news.hdb     |  3 ++
 3 files changed, 44 insertions(+)

diff --git a/code/services-core/search-service/src/main/java/nu/marginalia/search/SearchService.java b/code/services-core/search-service/src/main/java/nu/marginalia/search/SearchService.java
index 5fe5751e..30d978f6 100644
--- a/code/services-core/search-service/src/main/java/nu/marginalia/search/SearchService.java
+++ b/code/services-core/search-service/src/main/java/nu/marginalia/search/SearchService.java
@@ -58,6 +58,7 @@ public class SearchService extends Service {
         Spark.get("/public/search", searchQueryService::pathSearch);
         Spark.get("/public/site-search/:site/*", this::siteSearchRedir);
         Spark.get("/public/", frontPageService::render);
+        Spark.get("/public/news.xml", frontPageService::renderNewsFeed);
         Spark.get("/public/:resource", this::serveStatic);
 
         Spark.post("/public/site/suggest/", addToCrawlQueueService::suggestCrawling);
diff --git a/code/services-core/search-service/src/main/java/nu/marginalia/search/svc/SearchFrontPageService.java b/code/services-core/search-service/src/main/java/nu/marginalia/search/svc/SearchFrontPageService.java
index 8d409530..8ebd9f8f 100644
--- a/code/services-core/search-service/src/main/java/nu/marginalia/search/svc/SearchFrontPageService.java
+++ b/code/services-core/search-service/src/main/java/nu/marginalia/search/svc/SearchFrontPageService.java
@@ -14,6 +14,9 @@ import spark.Response;
 import java.io.IOException;
 import java.sql.SQLException;
 import java.time.LocalDate;
+import java.time.ZoneId;
+import java.time.ZonedDateTime;
+import java.time.format.DateTimeFormatter;
 import java.util.ArrayList;
 import java.util.List;
 
@@ -72,6 +75,43 @@ public class SearchFrontPageService {
         return items;
     }
 
+    public Object renderNewsFeed(Request request, Response response) {
+        List<NewsItem> newsItems = getNewsItems();
+
+        StringBuilder sb = new StringBuilder();
+
+        sb.append("""
+                <?xml version="1.0" encoding="UTF-8"?>
+                <rss version="2.0">
+                <channel>
+                <title>Marginalia Search News and Mentions</title>
+                <link>https://search.marginalia.nu/</link>
+                <description>News and Mentions of Marginalia Search</description>
+                <language>en-us</language>
+                <ttl>60</ttl>
+                """);
+
+        sb.append("<lastBuildDate>").append(ZonedDateTime.now().format(DateTimeFormatter.RFC_1123_DATE_TIME)).append("</lastBuildDate>\n");
+        sb.append("<pubDate>").append(ZonedDateTime.now().format(DateTimeFormatter.RFC_1123_DATE_TIME)).append("</pubDate>\n");
+        sb.append("<ttl>60</ttl>\n");
+        for (var item : newsItems) {
+            sb.append("<item>\n");
+            sb.append("<title>").append(item.title()).append("</title>\n");
+            sb.append("<link>").append(item.url()).append("</link>\n");
+            if (item.source != null) {
+                sb.append("<author>").append(item.source()).append("</author>\n");
+            }
+            sb.append("<pubDate>").append(item.date().atStartOfDay().atZone(ZoneId.systemDefault()).format(DateTimeFormatter.RFC_1123_DATE_TIME)).append("</pubDate>\n");
+            sb.append("</item>\n");
+        }
+        sb.append("</channel>\n");
+        sb.append("</rss>\n");
+
+        response.type("application/rss+xml");
+
+        return sb.toString();
+    }
+
     private record IndexModel(List<NewsItem> news, int searchPerMinute) { }
     private record NewsItem(String title, String url, String source, LocalDate date) {}
 }
diff --git a/code/services-core/search-service/src/main/resources/templates/search/index/index-news.hdb b/code/services-core/search-service/src/main/resources/templates/search/index/index-news.hdb
index ce1ae82e..52d5abd4 100644
--- a/code/services-core/search-service/src/main/resources/templates/search/index/index-news.hdb
+++ b/code/services-core/search-service/src/main/resources/templates/search/index/index-news.hdb
@@ -10,5 +10,8 @@
             {{/each}}
             </dl>
         </div>
+        <div class="utils">
+            <a href="/news.xml">📡 RSS Feed</a>
+        </div>
     </section>
 {{/if}}
\ No newline at end of file