Add mod alias support

README.md

@@ -202,7 +202,7 @@ Get Maven, then run the following command at the project root:
 mvn clean package
 ```
 
-This will build the project to `target/update-checker-0.4.12.jar`.
+This will build the project to `target/update-checker-0.5.0.jar`.
 
 ### Running the project
 
@@ -213,7 +213,7 @@ First, follow these steps to set it up:
 Then, to run the project, browse to where the JAR is in a terminal / command prompt, then run
 
 ```
-java -jar update-checker-0.4.12.jar [minutes]
+java -jar update-checker-0.5.0.jar [minutes]
 ```
 
 [minutes] is the wait delay in minutes between two GameBanana checks (defaults to 30). Be aware that the program makes ~13 API calls per check, and that the GameBanana API has a cap at 250 requests/hour.

pom.xml

@@ -6,7 +6,7 @@
 
     <groupId>ovh.maddie480.everest.updatechecker</groupId>
     <artifactId>update-checker</artifactId>
-    <version>0.4.12</version>
+    <version>0.5.0</version>
 
     <properties>
         <jdk.version>21</jdk.version>

src/main/java/ovh/maddie480/everest/updatechecker/ConnectionUtils.java

@@ -32,7 +32,7 @@ public static HttpURLConnection openConnectionWithTimeout(String url) throws IOE
             throw new IOException(e);
         }
 
-        con.setRequestProperty("User-Agent", "Everest-Update-Checker/0.4.12 (+https://github.com/maddie480/EverestUpdateCheckerServer)");
+        con.setRequestProperty("User-Agent", "Everest-Update-Checker/0.5.0 (+https://github.com/maddie480/EverestUpdateCheckerServer)");
         con.setRequestProperty("Accept-Encoding", "gzip");
 
         con.setConnectTimeout(10000);

src/main/java/ovh/maddie480/everest/updatechecker/DatabaseUpdater.java

@@ -165,8 +165,9 @@ private void saveDatabaseToYaml() throws IOException {
             new BananaMirrorRichPresenceIcons().update(modSearchDatabaseBuilder.getNsfwMods());
         }
 
-        // update the dependency graph with new entries.
+        // update the dependency graph and mod aliases with new entries.
         DependencyGraphBuilder.updateDependencyGraph();
+        ModAliasLister.updateModAliasList();
     }
 
     /**

src/main/java/ovh/maddie480/everest/updatechecker/EventListener.java

@@ -50,6 +50,8 @@ static void handle(Consumer<EventListener> functionCall) {
 
     public abstract void scannedModDependencies(String modId, int dependencyCount, int optionalDependencyCount);
 
+    public abstract void scannedModAliases(String modId, List<String> alsoKnownAsModIds);
+
     public abstract void modUpdatedIncrementally(String gameBananaType, int gameBananaId, String modName);
 
 
@@ -81,6 +83,8 @@ static void handle(Consumer<EventListener> functionCall) {
 
     public abstract void dependencyTreeScanException(String modId, Exception e);
 
+    public abstract void modAliasListScanException(String modId, Exception e);
+
     public abstract void zipFileWalkthroughError(String gameBananaType, int gameBananaId, String fileUrl, Exception e);
 
     public abstract void ahornPluginScanError(String fileUrl, Exception e);

src/main/java/ovh/maddie480/everest/updatechecker/ModAliasLister.java

@@ -0,0 +1,122 @@
+package ovh.maddie480.everest.updatechecker;
+
+import org.apache.commons.io.FileUtils;
+import org.apache.commons.io.IOUtils;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
+import java.io.*;
+import java.nio.file.Files;
+import java.nio.file.Paths;
+import java.util.Collections;
+import java.util.HashMap;
+import java.util.List;
+import java.util.Map;
+import java.util.zip.ZipEntry;
+import java.util.zip.ZipFile;
+
+import static ovh.maddie480.everest.updatechecker.DatabaseUpdater.checkZipSignature;
+
+public class ModAliasLister {
+    private static final Logger log = LoggerFactory.getLogger(ModAliasLister.class);
+
+    static void updateModAliasList() throws IOException {
+        Map<String, Map<String, Object>> oldAliasList;
+        try (InputStream is = Files.newInputStream(Paths.get("uploads/modaliases.yaml"))) {
+            oldAliasList = YamlUtil.load(is);
+        }
+
+        Map<String, Map<String, Object>> everestUpdate;
+        try (InputStream is = Files.newInputStream(Paths.get("uploads/everestupdate.yaml"))) {
+            everestUpdate = YamlUtil.load(is);
+        }
+
+        Map<String, Map<String, Object>> newAliasList = new HashMap<>();
+
+        // go across every entry in everest_update.yaml.
+        for (Map.Entry<String, Map<String, Object>> mod : everestUpdate.entrySet()) {
+            String name = mod.getKey();
+            String url = (String) mod.getValue().get(Main.serverConfig.mainServerIsMirror ? "MirrorURL" : "URL");
+
+            if (oldAliasList.containsKey(name) && oldAliasList.get(name).get("URL").toString().equals(url)) {
+                // we already have that mod!
+                newAliasList.put(name, oldAliasList.get(name));
+            } else {
+                // download file
+                ConnectionUtils.runWithRetry(() -> {
+                    try (OutputStream os = new BufferedOutputStream(Files.newOutputStream(Paths.get("mod-aliaslist.zip")))) {
+                        IOUtils.copy(new BufferedInputStream(ConnectionUtils.openStreamWithTimeout(url)), os);
+                        return null; // to fulfill this stupid method signature
+                    }
+                });
+
+                // check that its size makes sense
+                long actualSize = new File("mod-aliaslist.zip").length();
+                if (((int) mod.getValue().get("Size")) != actualSize) {
+                    FileUtils.forceDelete(new File("mod-aliaslist.zip"));
+                    throw new IOException("The announced file size (" + mod.getValue().get("Size") + ") does not match what we got (" + actualSize + ")" +
+                            " for file " + url);
+                }
+
+                // read its everest.yaml and collect the values of AlsoKnownAs
+                List<String> aliasList = Collections.emptyList();
+
+                try (ZipFile zipFile = ZipFileWithAutoEncoding.open("mod-aliaslist.zip")) {
+                    checkZipSignature(new File("mod-aliaslist.zip").toPath());
+
+                    ZipEntry everestYaml = zipFile.getEntry("everest.yaml");
+                    if (everestYaml == null) {
+                        everestYaml = zipFile.getEntry("everest.yml");
+                    }
+
+                    List<Map<String, Object>> everestYamlContents;
+                    try (InputStream is = zipFile.getInputStream(everestYaml)) {
+                        everestYamlContents = YamlUtil.loadNoFloats(is);
+                    }
+
+                    Map<String, Object> matchingYamlEntry = null;
+
+                    for (Map<String, Object> yamlEntry : everestYamlContents) {
+                        if (name.equals(yamlEntry.get("Name"))) {
+                            matchingYamlEntry = yamlEntry;
+                            break;
+                        }
+                    }
+
+                    if (matchingYamlEntry == null) {
+                        throw new IOException("Could not find matching entry that's supposed to be there since it's in everestupdate.yaml!");
+                    }
+
+                    // instanceof List<String> isn't a thing, but we can check if all elements are Strings instead!
+                    if (matchingYamlEntry.get("AlsoKnownAs") instanceof List aliases
+                            && aliases.stream().allMatch(e -> e instanceof String)) {
+
+                        aliasList = (List<String>) aliases;
+                    }
+
+                    log.info("Found aliases for {}: {}.", name, aliasList);
+                    final List<String> aliases = aliasList;
+                    EventListener.handle(listener -> listener.scannedModAliases(name, aliases));
+                } catch (Exception e) {
+                    // if a file cannot be read as a zip, no need to worry about it.
+                    // we will just write an empty array.
+                    log.warn("Could not read aliases from {}", name, e);
+                    EventListener.handle(listener -> listener.modAliasListScanException(name, e));
+                }
+
+                // save the entry we just got.
+                Map<String, Object> aliasEntry = new HashMap<>();
+                aliasEntry.put("URL", url);
+                aliasEntry.put("AlsoKnownAs", aliasList);
+                newAliasList.put(name, aliasEntry);
+
+                FileUtils.forceDelete(new File("mod-aliaslist.zip"));
+            }
+        }
+
+        // write it out!
+        try (OutputStream os = new FileOutputStream("uploads/modaliases.yaml")) {
+            YamlUtil.dump(newAliasList, os);
+        }
+    }
+}