Introduce Configuration File and Management

pom.xml

@@ -20,6 +20,10 @@
         <maven.compiler.source>20</maven.compiler.source>
         <maven.compiler.target>20</maven.compiler.target>
         <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
+        <jacksonVersion>2.15.2</jacksonVersion>
+        <junit5Version>5.10.0</junit5Version>
+        <log4j2Version>2.20.0</log4j2Version>
+        <systemStubsVersion>2.1.1</systemStubsVersion>
     </properties>
     <dependencies>
         <dependency>
@@ -37,19 +41,41 @@
             <groupId>org.junit.jupiter</groupId>
             <artifactId>junit-jupiter-engine</artifactId>
             <version>5.10.0</version>
-            <scope>test</scope>
+            <scope>${junit5Version}</scope>
         </dependency>
         <dependency>
             <groupId>org.junit.jupiter</groupId>
             <artifactId>junit-jupiter-params</artifactId>
-            <version>5.10.0</version>
+            <version>${junit5Version}</version>
+            <scope>test</scope>
+        </dependency>
+        <dependency>
+            <groupId>uk.org.webcompere</groupId>
+            <artifactId>system-stubs-core</artifactId>
+            <version>${systemStubsVersion}</version>
+            <scope>test</scope>
+        </dependency>
+        <dependency>
+            <groupId>uk.org.webcompere</groupId>
+            <artifactId>system-stubs-jupiter</artifactId>
+            <version>${systemStubsVersion}</version>
+            <scope>test</scope>
+        </dependency>
+        <dependency>
+            <groupId>org.assertj</groupId>
+            <artifactId>assertj-core</artifactId>
+            <version>3.24.2</version>
             <scope>test</scope>
         </dependency>
-
         <dependency>
             <groupId>com.fasterxml.jackson.core</groupId>
             <artifactId>jackson-databind</artifactId>
-            <version>2.14.2</version>
+            <version>${jacksonVersion}</version>
+        </dependency>
+        <dependency>
+            <groupId>com.fasterxml.jackson.dataformat</groupId>
+            <artifactId>jackson-dataformat-toml</artifactId>
+            <version>${jacksonVersion}</version>
         </dependency>
         <dependency>
             <groupId>io.javalin</groupId>
@@ -61,26 +87,20 @@
             <artifactId>httpclient5-fluent</artifactId>
             <version>5.2.1</version>
         </dependency>
-        <dependency>
-            <groupId>org.assertj</groupId>
-            <artifactId>assertj-core</artifactId>
-            <version>3.24.2</version>
-            <scope>test</scope>
-        </dependency>
         <dependency>
             <groupId>org.apache.logging.log4j</groupId>
             <artifactId>log4j-api</artifactId>
-            <version>2.20.0</version>
+            <version>${log4j2Version}</version>
         </dependency>
         <dependency>
             <groupId>org.apache.logging.log4j</groupId>
             <artifactId>log4j-core</artifactId>
-            <version>2.20.0</version>
+            <version>${log4j2Version}</version>
         </dependency>
         <dependency>
             <groupId>org.apache.logging.log4j</groupId>
             <artifactId>log4j-slf4j2-impl</artifactId>
-            <version>2.20.0</version>
+            <version>${log4j2Version}</version>
         </dependency>
         <dependency>
             <groupId>com.knuddels</groupId>

src/main/java/com/meta/chatbridge/Main.java

@@ -8,10 +8,44 @@
 
 package com.meta.chatbridge;
 
-import io.javalin.Javalin;
+import com.google.common.base.Preconditions;
+import com.meta.chatbridge.configuration.ConfigurationUtils;
+import com.meta.chatbridge.configuration.RootConfiguration;
+import java.io.IOException;
+import java.nio.file.Files;
+import java.nio.file.Path;
+import java.util.Arrays;
+import org.checkerframework.checker.nullness.qual.Nullable;
 
 public class Main {
-  private static final Javalin APP = Javalin.create();
 
-  public static void main(String[] strings) {}
+  static Path configurationFile(String[] strings) {
+    int configKeyLocation = Arrays.binarySearch(strings, "--config");
+    @Nullable String propertyConfigPath = System.getProperty("cp4m_configuration_file");
+    @Nullable String envConfigPath = System.getenv("CP4M_CONFIGURATION_FILE");
+    Path configPath;
+    if (configKeyLocation >= 0) {
+      int configPathLocation = configKeyLocation + 1;
+      Preconditions.checkArgument(
+          configPathLocation < strings.length,
+          "A path to the location of the file must be given if --config is provided");
+      configPath = Path.of(strings[configPathLocation]);
+    } else if (propertyConfigPath != null) {
+      configPath = Path.of(propertyConfigPath);
+    } else if (envConfigPath != null) {
+      configPath = Path.of(envConfigPath);
+    } else {
+      throw new IllegalArgumentException(
+          "No configuration file found. A configuration file must be provided via the commandline argument '--config', via the system property cp4m_configuration_file, or via the environment variable CP4M_CONFIGURATION_FILE");
+    }
+    Preconditions.checkArgument(
+        Files.exists(configPath), "given configuration at " + configPath + " does not exist");
+    return configPath;
+  }
+
+  public static void main(String[] strings) throws IOException {
+    Path configurationFile = configurationFile(strings);
+    RootConfiguration configuration = ConfigurationUtils.loadConfigurationFile(configurationFile);
+    configuration.toServicesRunner().start();
+  }
 }

src/main/java/com/meta/chatbridge/Pipeline.java → src/main/java/com/meta/chatbridge/Service.java

@@ -22,17 +22,17 @@
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 
-public class Pipeline<T extends Message> {
+public class Service<T extends Message> {
 
-  private static final Logger LOGGER = LoggerFactory.getLogger(Pipeline.class);
+  private static final Logger LOGGER = LoggerFactory.getLogger(Service.class);
   private final ExecutorService executorService = Executors.newCachedThreadPool();
   private final MessageHandler<T> handler;
   private final ChatStore<T> store;
   private final LLMPlugin<T> llmPlugin;
 
   private final String path;
 
-  public Pipeline(
+  public Service(
       ChatStore<T> store, MessageHandler<T> handler, LLMPlugin<T> llmPlugin, String path) {
     this.handler = Objects.requireNonNull(handler);
     this.store = Objects.requireNonNull(store);

src/main/java/com/meta/chatbridge/ServiceConfiguration.java

@@ -0,0 +1,52 @@
+/*
+ *
+ * Copyright (c) Meta Platforms, Inc. and affiliates.
+ *
+ * This source code is licensed under the MIT license found in the
+ * LICENSE file in the root directory of this source tree.
+ */
+
+package com.meta.chatbridge;
+
+import com.fasterxml.jackson.annotation.JsonCreator;
+import com.fasterxml.jackson.annotation.JsonProperty;
+import com.google.common.base.Preconditions;
+import java.util.Objects;
+
+public class ServiceConfiguration {
+  private final String webhookPath;
+  private final String handler;
+  private final String store;
+  private final String plugin;
+
+  @JsonCreator
+  ServiceConfiguration(
+      @JsonProperty("webhook_path") String webhookPath,
+      @JsonProperty("handler") String handler,
+      @JsonProperty("store") String store,
+      @JsonProperty("plugin") String plugin) {
+    Preconditions.checkArgument(
+        webhookPath != null && webhookPath.startsWith("/"),
+        "webhook_path must be present and it must start with a forward slash (/)");
+    this.webhookPath = webhookPath;
+    this.handler = Objects.requireNonNull(handler, "handler must be present");
+    this.store = Objects.requireNonNull(store, "store must be present");
+    this.plugin = Objects.requireNonNull(plugin, "plugin must be present");
+  }
+
+  public String webhookPath() {
+    return webhookPath;
+  }
+
+  public String handler() {
+    return handler;
+  }
+
+  public String store() {
+    return store;
+  }
+
+  public String plugin() {
+    return plugin;
+  }
+}

src/main/java/com/meta/chatbridge/PipelinesRunner.java → src/main/java/com/meta/chatbridge/ServicesRunner.java

@@ -16,37 +16,37 @@
 import java.util.Set;
 import org.checkerframework.common.returnsreceiver.qual.This;
 
-public class PipelinesRunner implements AutoCloseable {
+public class ServicesRunner implements AutoCloseable {
   private final Javalin app = Javalin.create();
   private boolean started = false;
   private int port = 8080;
 
-  private final Set<Pipeline<?>> pipelines = new HashSet<>();
+  private final Set<Service<?>> services = new HashSet<>();
 
-  private PipelinesRunner() {}
+  private ServicesRunner() {}
 
-  public static PipelinesRunner newInstance() {
-    return new PipelinesRunner();
+  public static ServicesRunner newInstance() {
+    return new ServicesRunner();
   }
 
-  public @This PipelinesRunner start() {
+  public @This ServicesRunner start() {
     if (!started) {
       started = true;
       app.start(port);
     }
     return this;
   }
 
-  public @This PipelinesRunner pipeline(Pipeline<?> pipeline) {
-    Preconditions.checkState(!started, "cannot add pipeline, server already started");
-    if (pipelines.add(pipeline)) {
-      pipeline.register(app);
+  public @This ServicesRunner service(Service<?> service) {
+    Preconditions.checkState(!started, "cannot add service, server already started");
+    if (services.add(service)) {
+      service.register(app);
     }
     return this;
   }
 
-  public Collection<Pipeline<?>> pipelines() {
-    return Collections.unmodifiableCollection(pipelines);
+  public Collection<Service<?>> services() {
+    return Collections.unmodifiableCollection(services);
   }
 
   public int port() {
@@ -62,7 +62,7 @@ public int port() {
    * @param port the port the server will start on
    * @return this
    */
-  public @This PipelinesRunner port(int port) {
+  public @This ServicesRunner port(int port) {
     Preconditions.checkState(!started, "cannot change port, server already started");
     this.port = port;
     return this;

src/main/java/com/meta/chatbridge/configuration/ConfigurationUtils.java

@@ -0,0 +1,69 @@
+/*
+ *
+ * Copyright (c) Meta Platforms, Inc. and affiliates.
+ *
+ * This source code is licensed under the MIT license found in the
+ * LICENSE file in the root directory of this source tree.
+ */
+
+package com.meta.chatbridge.configuration;
+
+import com.fasterxml.jackson.databind.DeserializationFeature;
+import com.fasterxml.jackson.databind.json.JsonMapper;
+import com.fasterxml.jackson.dataformat.toml.TomlMapper;
+import com.google.common.io.Files;
+import java.io.IOException;
+import java.nio.file.Path;
+import java.util.Collection;
+import java.util.List;
+
+public class ConfigurationUtils {
+
+  private static final Collection<DeserializationFeatureConfig> DESERIALIZATION_FEATURES =
+      List.of(
+          new DeserializationFeatureConfig(
+              DeserializationFeature.FAIL_ON_NULL_FOR_PRIMITIVES, true),
+          new DeserializationFeatureConfig(DeserializationFeature.WRAP_EXCEPTIONS, true),
+          new DeserializationFeatureConfig(DeserializationFeature.READ_ENUMS_USING_TO_STRING, true),
+          new DeserializationFeatureConfig(DeserializationFeature.USE_LONG_FOR_INTS, true),
+          new DeserializationFeatureConfig(
+              DeserializationFeature.ACCEPT_EMPTY_STRING_AS_NULL_OBJECT, false),
+          new DeserializationFeatureConfig(
+              DeserializationFeature.FAIL_ON_IGNORED_PROPERTIES, false));
+
+  private static final JsonMapper JSON_MAPPER;
+  private static final TomlMapper TOML_MAPPER;
+
+  static {
+    JsonMapper.Builder builder = JsonMapper.builder();
+    DESERIALIZATION_FEATURES.forEach(f -> builder.configure(f.feature(), f.state()));
+    JSON_MAPPER = builder.build();
+  }
+
+  static {
+    TomlMapper.Builder builder = TomlMapper.builder();
+    DESERIALIZATION_FEATURES.forEach(f -> builder.configure(f.feature(), f.state()));
+    TOML_MAPPER = builder.build();
+  }
+
+  public static JsonMapper jsonMapper() {
+    return JSON_MAPPER;
+  }
+
+  public static TomlMapper tomlMapper() {
+    return TOML_MAPPER;
+  }
+
+  public static RootConfiguration loadConfigurationFile(Path file) throws IOException {
+    String extension = Files.getFileExtension(file.toString());
+    if (extension.equals("json")) {
+      return jsonMapper().readValue(file.toFile(), RootConfiguration.class);
+    } else if (extension.equals("toml")) {
+      return tomlMapper().readValue(file.toFile(), RootConfiguration.class);
+    }
+    throw new IOException(
+        "Unknown file extension '" + extension + "', extension must be either json or toml.");
+  }
+
+  private record DeserializationFeatureConfig(DeserializationFeature feature, boolean state) {}
+}