Add events service (#1)

.github/workflows/ci.yml

@@ -0,0 +1,42 @@
+name: Test and Build
+
+on:
+  push:
+    branches:
+      - 'main'
+    tags:
+      - 'v*'
+  pull_request:
+    branches:
+      - 'main'
+
+jobs:
+  build-gradle:
+    runs-on: ubuntu-latest
+    steps:
+      - name: Checkout repository
+        uses: actions/checkout@v3
+        with:
+          fetch-depth: 0
+
+      - name: validate gradle wrapper
+        uses: gradle/wrapper-validation-action@v1
+
+      - uses: actions/setup-java@v3
+        with:
+          distribution: 'temurin'
+          java-version: '17'
+
+      - name: Setup Gradle
+        uses: gradle/gradle-build-action@v2
+
+      - name: Run build and tests with Gradle wrapper
+        run: ./gradlew test build
+
+      - name: Publish test report
+        uses: mikepenz/action-junit-report@v3
+        if: success() || failure()
+        with:
+          report_paths: 'build/test-results/test/TEST-*.xml'
+          annotate_notice: true
+          detailed_summary: true

build.gradle

@@ -3,6 +3,9 @@ plugins {
     id 'maven-publish'
 }
 
+import org.gradle.api.tasks.testing.logging.TestExceptionFormat
+import org.gradle.api.tasks.testing.logging.TestLogEvent
+
 group = 'net.luckperms'
 version = '0.1-SNAPSHOT'
 
@@ -21,6 +24,13 @@ repositories {
 
 test {
     useJUnitPlatform()
+    testLogging {
+        events = [TestLogEvent.PASSED, TestLogEvent.FAILED, TestLogEvent.SKIPPED]
+        exceptionFormat = TestExceptionFormat.FULL
+        showExceptions = true
+        showCauses = true
+        showStackTraces = true
+    }
 }
 
 dependencies {
@@ -29,6 +39,9 @@ dependencies {
     implementation 'com.squareup.okhttp3:okhttp:3.14.9'
     implementation 'com.squareup.okio:okio:1.17.5'
     implementation 'com.google.code.gson:gson:2.9.1'
+    implementation('com.launchdarkly:okhttp-eventsource:4.1.1') {
+        exclude(module: 'okhttp')
+    }
 
     testImplementation 'org.junit.jupiter:junit-jupiter-api:5.9.1'
     testImplementation 'org.junit.jupiter:junit-jupiter-engine:5.9.1'

src/main/java/net/luckperms/rest/EventCallAdapter.java

@@ -0,0 +1,172 @@
+/*
+ * This file is part of LuckPerms, licensed under the MIT License.
+ *
+ *  Copyright (c) lucko (Luck) <[email protected]>
+ *  Copyright (c) contributors
+ *
+ *  Permission is hereby granted, free of charge, to any person obtaining a copy
+ *  of this software and associated documentation files (the "Software"), to deal
+ *  in the Software without restriction, including without limitation the rights
+ *  to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ *  copies of the Software, and to permit persons to whom the Software is
+ *  furnished to do so, subject to the following conditions:
+ *
+ *  The above copyright notice and this permission notice shall be included in all
+ *  copies or substantial portions of the Software.
+ *
+ *  THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ *  IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ *  FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ *  AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ *  LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ *  OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+ *  SOFTWARE.
+ */
+
+package net.luckperms.rest;
+
+import com.google.gson.Gson;
+import com.launchdarkly.eventsource.ConnectStrategy;
+import com.launchdarkly.eventsource.EventSource;
+import com.launchdarkly.eventsource.FaultEvent;
+import com.launchdarkly.eventsource.MessageEvent;
+import com.launchdarkly.eventsource.StreamEvent;
+import net.luckperms.rest.event.EventCall;
+import net.luckperms.rest.event.EventProducer;
+import okhttp3.HttpUrl;
+import okhttp3.OkHttpClient;
+import retrofit2.Call;
+import retrofit2.CallAdapter;
+
+import java.lang.reflect.Type;
+import java.util.List;
+import java.util.concurrent.CopyOnWriteArrayList;
+import java.util.concurrent.Executor;
+import java.util.concurrent.ExecutorService;
+import java.util.function.Consumer;
+
+class EventCallAdapter implements CallAdapter<Object, EventCall<?>> {
+    private final Type eventType;
+    private final OkHttpClient client;
+    private final ExecutorService executorService;
+
+    EventCallAdapter(Type eventType, OkHttpClient client, ExecutorService executorService) {
+        this.eventType = eventType;
+        this.client = client;
+        this.executorService = executorService;
+    }
+
+    @Override
+    public Type responseType() {
+        return Object.class;
+    }
+
+    @Override
+    public EventCall<Object> adapt(Call<Object> call) {
+        return new EventCallImpl<>(call.request().url(), this.eventType, this.client, this.executorService);
+    }
+
+    private static final class EventCallImpl<E> implements EventCall<E> {
+        private final HttpUrl url;
+        private final Type eventType;
+        private final OkHttpClient client;
+        private final Executor executor;
+
+        EventCallImpl(HttpUrl url, Type eventType, OkHttpClient client, Executor executor) {
+            this.url = url;
+            this.eventType = eventType;
+            this.client = client;
+            this.executor = executor;
+        }
+
+        @Override
+        public EventProducer<E> subscribe() throws Exception {
+            EventSource eventSource = new EventSource.Builder(ConnectStrategy.http(this.url).httpClient(this.client)).build();
+            eventSource.start();
+
+            return new EventProducerImpl<>(eventSource, this.eventType, this.executor);
+        }
+    }
+
+    private static final class EventProducerImpl<E> implements EventProducer<E> {
+        private static final Gson GSON = new Gson();
+
+        private final EventSource eventSource;
+        private final Type eventType;
+
+        private final List<Consumer<E>> handlers;
+        private final List<Consumer<Exception>> errorHandlers;
+
+        private EventProducerImpl(EventSource eventSource, Type eventType, Executor executor) {
+            this.eventSource = eventSource;
+            this.eventType = eventType;
+            this.handlers = new CopyOnWriteArrayList<>();
+            this.errorHandlers = new CopyOnWriteArrayList<>();
+
+            executor.execute(this::pollForEvents);
+        }
+
+        private void pollForEvents() {
+            try {
+                for (StreamEvent event : this.eventSource.anyEvents()) {
+                    if (event instanceof MessageEvent) {
+                        handleMessage((MessageEvent) event);
+                    } else if (event instanceof FaultEvent) {
+                        handleError(((FaultEvent) event).getCause());
+                    }
+                }
+            } catch (Exception e) {
+                handleError(e);
+            }
+        }
+
+        private void handleMessage(MessageEvent e) {
+            String eventName = e.getEventName();
+            if (!eventName.equals("message")) {
+                return;
+            }
+
+            E parsedEvent;
+            try {
+                parsedEvent = GSON.fromJson(e.getData(), this.eventType);
+            } catch (Exception ex) {
+                handleError(ex);
+                return;
+            }
+
+            for (Consumer<E> handler : this.handlers) {
+                try {
+                    handler.accept(parsedEvent);
+                } catch (Exception ex) {
+                    handleError(ex);
+                }
+            }
+        }
+
+        private void handleError(Exception e) {
+            for (Consumer<Exception> errorHandler : this.errorHandlers) {
+                try {
+                    errorHandler.accept(e);
+                } catch (Exception ex) {
+                    // ignore
+                }
+            }
+        }
+
+        @Override
+        public void subscribe(Consumer<E> consumer) {
+            this.handlers.add(consumer);
+        }
+
+        @Override
+        public void errorHandler(Consumer<Exception> errorHandler) {
+            this.errorHandlers.add(errorHandler);
+        }
+
+        @Override
+        public void close() {
+            this.eventSource.close();
+        }
+    }
+
+}

src/main/java/net/luckperms/rest/EventCallAdapterFactory.java

@@ -0,0 +1,66 @@
+/*
+ * This file is part of LuckPerms, licensed under the MIT License.
+ *
+ *  Copyright (c) lucko (Luck) <[email protected]>
+ *  Copyright (c) contributors
+ *
+ *  Permission is hereby granted, free of charge, to any person obtaining a copy
+ *  of this software and associated documentation files (the "Software"), to deal
+ *  in the Software without restriction, including without limitation the rights
+ *  to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ *  copies of the Software, and to permit persons to whom the Software is
+ *  furnished to do so, subject to the following conditions:
+ *
+ *  The above copyright notice and this permission notice shall be included in all
+ *  copies or substantial portions of the Software.
+ *
+ *  THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ *  IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ *  FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ *  AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ *  LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ *  OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+ *  SOFTWARE.
+ */
+
+package net.luckperms.rest;
+
+import net.luckperms.rest.event.EventCall;
+import okhttp3.OkHttpClient;
+import retrofit2.CallAdapter;
+import retrofit2.Retrofit;
+
+import java.lang.annotation.Annotation;
+import java.lang.reflect.ParameterizedType;
+import java.lang.reflect.Type;
+import java.util.concurrent.ExecutorService;
+import java.util.concurrent.Executors;
+
+class EventCallAdapterFactory extends CallAdapter.Factory implements AutoCloseable {
+    private final OkHttpClient client;
+    private final ExecutorService executorService;
+
+    EventCallAdapterFactory(OkHttpClient client) {
+        this.client = client;
+        this.executorService = Executors.newCachedThreadPool();
+    }
+
+    @Override
+    public CallAdapter<?, ?> get(Type returnType, Annotation[] annotations, Retrofit retrofit) {
+        if (getRawType(returnType) != EventCall.class) {
+            return null;
+        }
+
+        if (!(returnType instanceof ParameterizedType)) {
+            throw new IllegalArgumentException("Return type must be parameterized as EventCall<Foo> or EventCall<? extends Foo>");
+        }
+
+        Type responseType = getParameterUpperBound(0, (ParameterizedType) returnType);
+        return new EventCallAdapter(responseType, this.client, this.executorService);
+    }
+
+    @Override
+    public void close() {
+        this.executorService.shutdown();
+    }
+}

src/main/java/net/luckperms/rest/LuckPermsRestClient.java

@@ -26,6 +26,7 @@
 package net.luckperms.rest;
 
 import net.luckperms.rest.service.ActionService;
+import net.luckperms.rest.service.EventService;
 import net.luckperms.rest.service.GroupService;
 import net.luckperms.rest.service.MiscService;
 import net.luckperms.rest.service.TrackService;
@@ -75,6 +76,13 @@ static Builder builder() {
      */
     ActionService actions();
 
+    /**
+     * Gets the event service.
+     *
+     * @return the event service
+     */
+    EventService events();
+
     /**
      * Gets the misc service.
      *