Various improvements to plugin metadata

- Add plugin (display) name and plugin URL
 - Make everything except plugin ID optional (instead of empty string)
 - Exclude empty properties from generated velocity-plugin.json
 - Make plugin author list immutable
 - Other (minor) cleanup and refactoring

.gitignore

@@ -131,3 +131,4 @@ logs/
 /velocity.toml
 server-icon.png
 /bin/
+run/

api/src/ap/java/com/velocitypowered/api/plugin/ap/SerializedPluginDescription.java

@@ -1,8 +1,9 @@
 package com.velocitypowered.api.plugin.ap;
 
 import com.google.common.base.Preconditions;
-import com.google.common.collect.ImmutableList;
+import com.google.common.base.Strings;
 import com.velocitypowered.api.plugin.Plugin;
+import org.checkerframework.checker.nullness.qual.Nullable;
 
 import java.util.ArrayList;
 import java.util.Arrays;
@@ -11,22 +12,23 @@ import java.util.Objects;
 import java.util.stream.Collectors;
 
 public class SerializedPluginDescription {
+    // @Nullable is used here to make GSON skip these in the serialized file
     private final String id;
-    private final List<String> authors;
+    private final @Nullable String name;
+    private final @Nullable String version;
+    private final @Nullable String url;
+    private final @Nullable List<String> authors;
+    private final @Nullable List<Dependency> dependencies;
     private final String main;
-    private final String version;
-    private final List<Dependency> dependencies;
 
-    public SerializedPluginDescription(String id, List<String> author, String main, String version) {
-        this(id, author, main, version, ImmutableList.of());
-    }
-
-    public SerializedPluginDescription(String id, List<String> authors, String main, String version, List<Dependency> dependencies) {
+    public SerializedPluginDescription(String id, String name, String version, String url, List<String> authors, List<Dependency> dependencies, String main) {
         this.id = Preconditions.checkNotNull(id, "id");
-        this.authors = Preconditions.checkNotNull(authors, "authors");
+        this.name = Strings.emptyToNull(name);
+        this.version = Strings.emptyToNull(version);
+        this.url = Strings.emptyToNull(url);
+        this.authors = authors == null || authors.isEmpty() ? null : authors;
+        this.dependencies = dependencies == null || dependencies.isEmpty() ? null : dependencies;
         this.main = Preconditions.checkNotNull(main, "main");
-        this.version = Preconditions.checkNotNull(version, "version");
-        this.dependencies = ImmutableList.copyOf(dependencies);
     }
 
     public static SerializedPluginDescription from(Plugin plugin, String qualifiedName) {
@@ -34,54 +36,66 @@ public class SerializedPluginDescription {
         for (com.velocitypowered.api.plugin.Dependency dependency : plugin.dependencies()) {
             dependencies.add(new Dependency(dependency.id(), dependency.optional()));
         }
-        return new SerializedPluginDescription(plugin.id(), Arrays.stream(plugin.authors()).filter(author -> !author.isEmpty()).collect(Collectors.toList()), qualifiedName, plugin.version(), dependencies);
+        return new SerializedPluginDescription(plugin.id(), plugin.name(), plugin.version(), plugin.url(),
+                Arrays.stream(plugin.authors()).filter(author -> !author.isEmpty()).collect(Collectors.toList()), dependencies, qualifiedName);
     }
 
     public String getId() {
         return id;
     }
 
-    public List<String> getAuthors() {
+    public @Nullable String getName() {
+        return name;
+    }
+
+    public @Nullable String getVersion() {
+        return version;
+    }
+
+    public @Nullable String getUrl() {
+        return url;
+    }
+
+    public @Nullable List<String> getAuthors() {
         return authors;
     }
 
+    public @Nullable List<Dependency> getDependencies() {
+        return dependencies;
+    }
+
     public String getMain() {
         return main;
     }
 
-    public String getVersion() {
-        return version;
-    }
-
-    public List<Dependency> getDependencies() {
-        return dependencies;
-    }
-
     @Override
     public boolean equals(Object o) {
         if (this == o) return true;
         if (o == null || getClass() != o.getClass()) return false;
         SerializedPluginDescription that = (SerializedPluginDescription) o;
         return Objects.equals(id, that.id) &&
-                Objects.equals(authors, that.authors) &&
-                Objects.equals(main, that.main) &&
+                Objects.equals(name, that.name) &&
                 Objects.equals(version, that.version) &&
-                Objects.equals(dependencies, that.dependencies);
+                Objects.equals(url, that.url) &&
+                Objects.equals(authors, that.authors) &&
+                Objects.equals(dependencies, that.dependencies) &&
+                Objects.equals(main, that.main);
     }
 
     @Override
     public int hashCode() {
-        return Objects.hash(id, authors, main, version, dependencies);
+        return Objects.hash(id, name, version, url, authors, dependencies);
     }
 
-    @Override
-    public String toString() {
+    @Override public String toString() {
         return "SerializedPluginDescription{" +
                 "id='" + id + '\'' +
-                ", authors='" + authors + '\'' +
-                ", main='" + main + '\'' +
+                ", name='" + name + '\'' +
                 ", version='" + version + '\'' +
+                ", url='" + url + '\'' +
+                ", authors=" + authors +
                 ", dependencies=" + dependencies +
+                ", main='" + main + '\'' +
                 '}';
     }
 

api/src/main/java/com/velocitypowered/api/plugin/Plugin.java

@@ -21,6 +21,14 @@ public @interface Plugin {
      */
     String id();
 
+    /**
+     * The human readable name of the plugin as to be used in descriptions and
+     * similar things.
+     *
+     * @return The plugin name, or an empty string if unknown
+     */
+    String name() default "";
+
     /**
      * The version of the plugin.
      *
@@ -28,6 +36,13 @@ public @interface Plugin {
      */
     String version() default "";
 
+    /**
+     * The URL or website of the plugin.
+     *
+     * @return The plugin url, or an empty string if unknown
+     */
+    String url() default "";
+
     /**
      * The author of the plugin.
      *

api/src/main/java/com/velocitypowered/api/plugin/PluginDescription.java

@@ -1,5 +1,6 @@
 package com.velocitypowered.api.plugin;
 
+import com.google.common.collect.ImmutableList;
 import com.google.common.collect.ImmutableSet;
 import com.velocitypowered.api.plugin.meta.PluginDependency;
 
@@ -7,7 +8,6 @@ import java.nio.file.Path;
 import java.util.Collection;
 import java.util.List;
 import java.util.Optional;
-import java.util.Set;
 import java.util.regex.Pattern;
 
 /**
@@ -29,21 +29,45 @@ public interface PluginDescription {
      */
     String getId();
 
+    /**
+     * Gets the name of the {@link Plugin} within this container.
+     *
+     * @return an {@link Optional} with the plugin name, may be empty
+     * @see Plugin#name()
+     */
+    default Optional<String> getName() {
+        return Optional.empty();
+    }
+
     /**
      * Gets the version of the {@link Plugin} within this container.
      *
-     * @return the plugin version
+     * @return an {@link Optional} with the plugin version, may be empty
      * @see Plugin#version()
      */
-    String getVersion();
+    default Optional<String> getVersion() {
+        return Optional.empty();
+    }
+
+    /**
+     * Gets the url or website of the {@link Plugin} within this container.
+     *
+     * @return an {@link Optional} with the plugin url, may be empty
+     * @see Plugin#url()
+     */
+    default Optional<String> getUrl() {
+        return Optional.empty();
+    }
 
     /**
      * Gets the authors of the {@link Plugin} within this container.
      *
-     * @return the plugin authors
+     * @return the plugin authors, may be empty
      * @see Plugin#authors()
      */
-    List<String> getAuthors();
+    default List<String> getAuthors() {
+        return ImmutableList.of();
+    }
 
     /**
      * Gets a {@link Collection} of all dependencies of the {@link Plugin} within

api/src/main/java/com/velocitypowered/api/plugin/meta/PluginDependency.java

@@ -3,6 +3,7 @@ package com.velocitypowered.api.plugin.meta;
 import javax.annotation.Nullable;
 
 import java.util.Objects;
+import java.util.Optional;
 
 import static com.google.common.base.Preconditions.checkArgument;
 import static com.google.common.base.Preconditions.checkNotNull;
@@ -36,11 +37,10 @@ public final class PluginDependency {
     /**
      * Returns the version this {@link PluginDependency} should match.
      *
-     * @return the plugin version, or {@code null} if unspecified
+     * @return an {@link Optional} with the plugin version, may be empty
      */
-    @Nullable
-    public String getVersion() {
-        return version;
+    public Optional<String> getVersion() {
+        return Optional.ofNullable(version);
     }
 
     /**

proxy/src/main/java/com/velocitypowered/proxy/plugin/loader/JavaPluginLoader.java

@@ -77,14 +77,7 @@ public class JavaPluginLoader implements PluginLoader {
         Injector injector = Guice.createInjector(new VelocityPluginModule(server, javaDescription, baseDirectory));
         Object instance = injector.getInstance(javaDescription.getMainClass());
 
-        return new VelocityPluginContainer(
-                description.getId(),
-                description.getVersion(),
-                description.getAuthors(),
-                description.getDependencies(),
-                source.get(),
-                instance
-        );
+        return new VelocityPluginContainer(description, instance);
     }
 
     private Optional<SerializedPluginDescription> getSerializedPluginInfo(Path source) throws Exception {
@@ -105,13 +98,17 @@ public class JavaPluginLoader implements PluginLoader {
     private VelocityPluginDescription createDescription(SerializedPluginDescription description, Path source, Class mainClass) {
         Set<PluginDependency> dependencies = new HashSet<>();
 
-        for (SerializedPluginDescription.Dependency dependency : description.getDependencies()) {
-            dependencies.add(toDependencyMeta(dependency));
+        if (description.getDependencies() != null) {
+            for (SerializedPluginDescription.Dependency dependency : description.getDependencies()) {
+                dependencies.add(toDependencyMeta(dependency));
+            }
         }
 
         return new JavaVelocityPluginDescription(
                 description.getId(),
+                description.getName(),
                 description.getVersion(),
+                description.getUrl(),
                 description.getAuthors(),
                 dependencies,
                 source,

proxy/src/main/java/com/velocitypowered/proxy/plugin/loader/VelocityPluginContainer.java

@@ -2,24 +2,21 @@ package com.velocitypowered.proxy.plugin.loader;
 
 import com.velocitypowered.api.plugin.PluginContainer;
 import com.velocitypowered.api.plugin.PluginDescription;
-import com.velocitypowered.api.plugin.meta.PluginDependency;
 
-import java.nio.file.Path;
-import java.util.Collection;
-import java.util.List;
 import java.util.Optional;
 
-public class VelocityPluginContainer extends VelocityPluginDescription implements PluginContainer {
+public class VelocityPluginContainer implements PluginContainer {
+    private final PluginDescription description;
     private final Object instance;
 
-    public VelocityPluginContainer(String id, String version, List<String> authors, Collection<PluginDependency> dependencies, Path source, Object instance) {
-        super(id, version, authors, dependencies, source);
+    public VelocityPluginContainer(PluginDescription description, Object instance) {
+        this.description = description;
         this.instance = instance;
     }
 
     @Override
     public PluginDescription getDescription() {
-        return this;
+        return this.description;
     }
 
     @Override

proxy/src/main/java/com/velocitypowered/proxy/plugin/loader/VelocityPluginDescription.java

@@ -1,8 +1,11 @@
 package com.velocitypowered.proxy.plugin.loader;
 
+import com.google.common.base.Strings;
+import com.google.common.collect.ImmutableList;
 import com.google.common.collect.Maps;
 import com.velocitypowered.api.plugin.PluginDescription;
 import com.velocitypowered.api.plugin.meta.PluginDependency;
+import org.checkerframework.checker.nullness.qual.Nullable;
 
 import java.nio.file.Path;
 import java.util.Collection;
@@ -14,15 +17,20 @@ import static com.google.common.base.Preconditions.checkNotNull;
 
 public class VelocityPluginDescription implements PluginDescription {
     private final String id;
-    private final String version;
+    private final @Nullable String name;
+    private final @Nullable String version;
+    private final @Nullable String url;
     private final List<String> authors;
     private final Map<String, PluginDependency> dependencies;
     private final Path source;
 
-    public VelocityPluginDescription(String id, String version, List<String> authors, Collection<PluginDependency> dependencies, Path source) {
+    public VelocityPluginDescription(String id, @Nullable String name, @Nullable String version, @Nullable String url,
+            @Nullable List<String> authors, Collection<PluginDependency> dependencies, Path source) {
         this.id = checkNotNull(id, "id");
-        this.version = checkNotNull(version, "version");
-        this.authors = checkNotNull(authors, "authors");
+        this.name = Strings.emptyToNull(name);
+        this.version = Strings.emptyToNull(version);
+        this.url = Strings.emptyToNull(url);
+        this.authors = authors == null ? ImmutableList.of() : ImmutableList.copyOf(authors);
         this.dependencies = Maps.uniqueIndex(dependencies, PluginDependency::getId);
         this.source = source;
     }
@@ -33,8 +41,18 @@ public class VelocityPluginDescription implements PluginDescription {
     }
 
     @Override
-    public String getVersion() {
-        return version;
+    public Optional<String> getName() {
+        return Optional.ofNullable(name);
+    }
+
+    @Override
+    public Optional<String> getVersion() {
+        return Optional.ofNullable(version);
+    }
+
+    @Override
+    public Optional<String> getUrl() {
+        return Optional.ofNullable(url);
     }
 
     @Override

proxy/src/main/java/com/velocitypowered/proxy/plugin/loader/java/JavaVelocityPluginDescription.java

@@ -10,14 +10,15 @@ import java.util.List;
 import static com.google.common.base.Preconditions.checkNotNull;
 
 public class JavaVelocityPluginDescription extends VelocityPluginDescription {
-    private final Class mainClass;
+    private final Class<?> mainClass;
 
-    public JavaVelocityPluginDescription(String id, String version, List<String> authors, Collection<PluginDependency> dependencies, Path source, Class mainClass) {
-        super(id, version, authors, dependencies, source);
+    public JavaVelocityPluginDescription(String id, String name, String version, String url, List<String> authors,
+            Collection<PluginDependency> dependencies, Path source, Class<?> mainClass) {
+        super(id, name, version, url, authors, dependencies, source);
         this.mainClass = checkNotNull(mainClass);
     }
 
-    public Class getMainClass() {
+    public Class<?> getMainClass() {
         return mainClass;
     }
 }

proxy/src/main/java/com/velocitypowered/proxy/plugin/loader/java/SerializedPluginDescription.java

@@ -1,8 +1,9 @@
 package com.velocitypowered.proxy.plugin.loader.java;
 
 import com.google.common.base.Preconditions;
-import com.google.common.collect.ImmutableList;
+import com.google.common.base.Strings;
 import com.velocitypowered.api.plugin.Plugin;
+import org.checkerframework.checker.nullness.qual.Nullable;
 
 import java.util.ArrayList;
 import java.util.Arrays;
@@ -11,22 +12,23 @@ import java.util.Objects;
 import java.util.stream.Collectors;
 
 public class SerializedPluginDescription {
+    // @Nullable is used here to make GSON skip these in the serialized file
     private final String id;
-    private final List<String> authors;
+    private final @Nullable String name;
+    private final @Nullable String version;
+    private final @Nullable String url;
+    private final @Nullable List<String> authors;
+    private final @Nullable List<Dependency> dependencies;
     private final String main;
-    private final String version;
-    private final List<Dependency> dependencies;
 
-    public SerializedPluginDescription(String id, List<String> authors, String main, String version) {
-        this(id, authors, main, version, ImmutableList.of());
-    }
-
-    public SerializedPluginDescription(String id, List<String> authors, String main, String version, List<Dependency> dependencies) {
+    public SerializedPluginDescription(String id, String name, String version, String url, List<String> authors, List<Dependency> dependencies, String main) {
         this.id = Preconditions.checkNotNull(id, "id");
-        this.authors = Preconditions.checkNotNull(authors, "author");
+        this.name = Strings.emptyToNull(name);
+        this.version = Strings.emptyToNull(version);
+        this.url = Strings.emptyToNull(url);
+        this.authors = authors == null || authors.isEmpty() ? null : authors;
+        this.dependencies = dependencies == null || dependencies.isEmpty() ? null : dependencies;
         this.main = Preconditions.checkNotNull(main, "main");
-        this.version = Preconditions.checkNotNull(version, "version");
-        this.dependencies = ImmutableList.copyOf(dependencies);
     }
 
     public static SerializedPluginDescription from(Plugin plugin, String qualifiedName) {
@@ -34,54 +36,66 @@ public class SerializedPluginDescription {
         for (com.velocitypowered.api.plugin.Dependency dependency : plugin.dependencies()) {
             dependencies.add(new Dependency(dependency.id(), dependency.optional()));
         }
-        return new SerializedPluginDescription(plugin.id(), Arrays.stream(plugin.authors()).filter(author -> !author.isEmpty()).collect(Collectors.toList()), qualifiedName, plugin.version(), dependencies);
+        return new SerializedPluginDescription(plugin.id(), plugin.name(), plugin.version(), plugin.url(),
+                Arrays.stream(plugin.authors()).filter(author -> !author.isEmpty()).collect(Collectors.toList()), dependencies, qualifiedName);
     }
 
     public String getId() {
         return id;
     }
 
-    public List<String> getAuthors() {
+    public @Nullable String getName() {
+        return name;
+    }
+
+    public @Nullable String getVersion() {
+        return version;
+    }
+
+    public @Nullable String getUrl() {
+        return url;
+    }
+
+    public @Nullable List<String> getAuthors() {
         return authors;
     }
 
+    public @Nullable List<Dependency> getDependencies() {
+        return dependencies;
+    }
+
     public String getMain() {
         return main;
     }
 
-    public String getVersion() {
-        return version;
-    }
-
-    public List<Dependency> getDependencies() {
-        return dependencies;
-    }
-
     @Override
     public boolean equals(Object o) {
         if (this == o) return true;
         if (o == null || getClass() != o.getClass()) return false;
         SerializedPluginDescription that = (SerializedPluginDescription) o;
         return Objects.equals(id, that.id) &&
-                Objects.equals(authors, that.authors) &&
-                Objects.equals(main, that.main) &&
+                Objects.equals(name, that.name) &&
                 Objects.equals(version, that.version) &&
-                Objects.equals(dependencies, that.dependencies);
+                Objects.equals(url, that.url) &&
+                Objects.equals(authors, that.authors) &&
+                Objects.equals(dependencies, that.dependencies) &&
+                Objects.equals(main, that.main);
     }
 
     @Override
     public int hashCode() {
-        return Objects.hash(id, authors, main, version, dependencies);
+        return Objects.hash(id, name, version, url, authors, dependencies);
     }
 
-    @Override
-    public String toString() {
+    @Override public String toString() {
         return "SerializedPluginDescription{" +
                 "id='" + id + '\'' +
-                ", authors='" + authors + '\'' +
-                ", main='" + main + '\'' +
+                ", name='" + name + '\'' +
                 ", version='" + version + '\'' +
+                ", url='" + url + '\'' +
+                ", authors=" + authors +
                 ", dependencies=" + dependencies +
+                ", main='" + main + '\'' +
                 '}';
     }
 

proxy/src/test/java/com/velocitypowered/proxy/testutil/FakePluginManager.java

@@ -8,8 +8,6 @@ import org.checkerframework.checker.nullness.qual.NonNull;
 
 import java.nio.file.Path;
 import java.util.Collection;
-import java.util.Collections;
-import java.util.List;
 import java.util.Optional;
 
 public class FakePluginManager implements PluginManager {
@@ -68,22 +66,7 @@ public class FakePluginManager implements PluginManager {
 
         @Override
         public @NonNull PluginDescription getDescription() {
-            return new PluginDescription() {
-                @Override
-                public String getId() {
-                    return id;
-                }
-
-                @Override
-                public String getVersion() {
-                    return "";
-                }
-
-                @Override
-                public List<String> getAuthors() {
-                    return Collections.emptyList();
-                }
-            };
+            return () -> id;
         }
 
         @Override