Merge pull request #117 from avaje/feature/extract-propertiesparser

Extract PropertiesParser (so that it is accessible to plugins)

avaje-aws-appconfig/pom.xml

@@ -10,7 +10,8 @@
     <relativePath/>
   </parent>
 
-  <artifactId>avaje-aws-appconfig</artifactId>
+  <groupId>io.avaje</groupId>
+  <artifactId>avaje-config-aws-appconfig</artifactId>
   <version>0.3-SNAPSHOT</version>
 
   <properties>

avaje-aws-appconfig/src/main/java/io/avaje/aws/appconfig/AppConfigFetcher.java → avaje-aws-appconfig/src/main/java/io/avaje/config/awsappconfig/AppConfigFetcher.java

@@ -1,6 +1,6 @@
-package io.avaje.aws.appconfig;
+package io.avaje.config.awsappconfig;
 
-public interface AppConfigFetcher {
+interface AppConfigFetcher {
 
   static AppConfigFetcher.Builder builder() {
     return new DAppConfigFetcher.Builder();

avaje-aws-appconfig/src/main/java/io/avaje/config/awsappconfig/AwsAppConfigPlugin.java

@@ -0,0 +1,142 @@
+package io.avaje.config.awsappconfig;
+
+import io.avaje.config.ConfigParser;
+import io.avaje.config.Configuration;
+import io.avaje.config.ConfigurationSource;
+
+import java.io.StringReader;
+import java.time.Instant;
+import java.util.Map;
+import java.util.concurrent.atomic.AtomicReference;
+import java.util.concurrent.locks.ReentrantLock;
+
+import static java.lang.System.Logger.Level.*;
+
+/**
+ * Plugin that loads AWS AppConfig as Yaml or Properties.
+ * <p>
+ * By default, will periodically reload the configuration if it has changed.
+ */
+public final class AwsAppConfigPlugin implements ConfigurationSource {
+
+  private static final System.Logger log = System.getLogger("io.avaje.config.AwsAppConfig");
+
+  private Loader loader;
+
+  @Override
+  public void load(Configuration configuration) {
+    if (!configuration.enabled("aws.appconfig.enabled", true)) {
+      log.log(INFO, "AwsAppConfig plugin is disabled");
+      return;
+    }
+    loader = new Loader(configuration);
+    loader.reload();
+  }
+
+  @Override
+  public void reload() {
+    if (loader != null) {
+      loader.reload();
+    }
+  }
+
+  static final class Loader {
+
+    private final Configuration configuration;
+    private final AppConfigFetcher fetcher;
+    private final ConfigParser yamlParser;
+    private final ConfigParser propertiesParser;
+    private final ReentrantLock lock = new ReentrantLock();
+    private final AtomicReference<Instant> validUntil;
+    private final long nextRefreshSeconds;
+
+    private String currentVersion = "none";
+
+    Loader(Configuration configuration) {
+      this.validUntil = new AtomicReference<>(Instant.now().minusSeconds(1));
+      this.configuration = configuration;
+      this.propertiesParser = configuration.parser("properties").orElseThrow();
+      this.yamlParser = configuration.parser("yaml").orElse(null);
+      if (yamlParser == null) {
+        log.log(WARNING, "No Yaml parser registered");
+      }
+
+      var app = configuration.get("aws.appconfig.application");
+      var env = configuration.get("aws.appconfig.environment");
+      var con = configuration.get("aws.appconfig.configuration", env + "-" + app);
+
+      this.fetcher = AppConfigFetcher.builder()
+        .application(app)
+        .environment(env)
+        .configuration(con)
+        .build();
+
+      boolean pollEnabled = configuration.enabled("aws.appconfig.poll.enabled", true);
+      long pollSeconds = configuration.getLong("aws.appconfig.poll.seconds", 45L);
+      this.nextRefreshSeconds = configuration.getLong("aws.appconfig.refresh.seconds", pollSeconds - 1);
+      if (pollEnabled) {
+        configuration.schedule(pollSeconds * 1000L, pollSeconds * 1000L, this::reload);
+      }
+    }
+
+    void reload() {
+      if (reloadRequired()) {
+        performReload();
+      }
+    }
+
+    private boolean reloadRequired() {
+      return validUntil.get().isAfter(Instant.now());
+    }
+
+    private void performReload() {
+      lock.lock();
+      try {
+        if (!reloadRequired()) {
+          return;
+        }
+        AppConfigFetcher.Result result = fetcher.fetch();
+        if (currentVersion.equals(result.version())) {
+          log.log(TRACE, "AwsAppConfig unchanged, version {0}", currentVersion);
+        } else {
+          String contentType = result.contentType();
+          if (log.isLoggable(TRACE)) {
+            log.log(TRACE, "AwsAppConfig fetched version:{0} contentType:{1} body:{2}", result.version(), contentType, result.body());
+          }
+          Map<String, String> keyValues = parse(result);
+          configuration.eventBuilder("AwsAppConfig")
+            .putAll(keyValues)
+            .publish();
+          currentVersion = result.version();
+          debugLog(result, keyValues.size());
+        }
+        // move the next valid until time
+        validUntil.set(Instant.now().plusSeconds(nextRefreshSeconds));
+
+      } catch (Exception e) {
+        log.log(ERROR, "Error fetching or processing AwsAppConfig", e);
+      } finally {
+        lock.unlock();
+      }
+    }
+
+    private Map<String, String> parse(AppConfigFetcher.Result result) {
+      ConfigParser parser = parser(result.contentType());
+      return parser.load(new StringReader(result.body()));
+    }
+
+    private ConfigParser parser(String contentType) {
+      if (contentType.endsWith("yaml")) {
+        return yamlParser;
+      } else {
+        return propertiesParser;
+      }
+    }
+
+    private static void debugLog(AppConfigFetcher.Result result, int size) {
+      if (log.isLoggable(DEBUG)) {
+        log.log(DEBUG, "AwsAppConfig loaded version {0} with {1} properties", result.version(), size);
+      }
+    }
+  }
+}

avaje-aws-appconfig/src/main/java/io/avaje/aws/appconfig/DAppConfigFetcher.java → avaje-aws-appconfig/src/main/java/io/avaje/config/awsappconfig/DAppConfigFetcher.java

@@ -1,4 +1,4 @@
-package io.avaje.aws.appconfig;
+package io.avaje.config.awsappconfig;
 
 import java.io.IOException;
 import java.net.URI;

avaje-aws-appconfig/src/main/java/io/avaje/aws/appconfig/DResult.java → avaje-aws-appconfig/src/main/java/io/avaje/config/awsappconfig/DResult.java

@@ -1,11 +1,12 @@
-package io.avaje.aws.appconfig;
+package io.avaje.config.awsappconfig;
 
 final class DResult implements AppConfigFetcher.Result {
 
   private final String version;
   private final String contentType;
   private final String body;
-  public DResult(String version, String contentType, String body) {
+
+  DResult(String version, String contentType, String body) {
     this.version = version;
     this.contentType = contentType;
     this.body = body;

avaje-aws-appconfig/src/main/java/module-info.java

@@ -1,10 +1,10 @@
-import io.avaje.aws.appconfig.AppConfigPlugin;
+import io.avaje.config.awsappconfig.AwsAppConfigPlugin;
 
-module io.avaje.aws.appconfig {
+module io.avaje.config.awsappconfig {
 
-  exports io.avaje.aws.appconfig;
+  exports io.avaje.config.awsappconfig;
 
   requires io.avaje.config;
   requires java.net.http;
-  provides io.avaje.config.ConfigurationSource with AppConfigPlugin;
+  provides io.avaje.config.ConfigurationSource with AwsAppConfigPlugin;
 }

avaje-aws-appconfig/src/main/resources/META-INF/services/io.avaje.config.ConfigurationSource

@@ -1 +1 @@
-io.avaje.aws.appconfig.AppConfigPlugin
+io.avaje.config.awsappconfig.AwsAppConfigPlugin

avaje-config/src/main/java/io/avaje/config/Configuration.java

@@ -482,6 +482,15 @@ default boolean enabled(String key, boolean enabledDefault) {
    */
   void loadIntoSystemProperties();
 
+  /**
+   * Trigger a {@link ConfigurationSource#reload()} on all the sources.
+   * <p>
+   * Generally configuration sources will schedule a periodic refresh of their
+   * configuration but there are cases like Lambda where it can be useful to
+   * trigger a refresh explicitly (e.g. on Lambda invocation).
+   */
+  void reloadSources();
+
   /**
    * Return the number of configuration properties.
    */

avaje-config/src/main/java/io/avaje/config/ConfigurationSource.java

@@ -23,4 +23,15 @@ public interface ConfigurationSource {
    * @param configuration The configuration with initially properties.
    */
   void load(Configuration configuration);
+
+  /**
+   * Explicitly reload the configuration source.
+   * <p>
+   * Generally the configuration source will schedule a periodic refresh of its
+   * configuration but there are cases like Lambda where it can be useful to
+   * trigger a refresh explicitly and manually (e.g. on Lambda invocation).
+   */
+  default void reload() {
+    // do nothing by default
+  }
 }

avaje-config/src/main/java/io/avaje/config/CoreComponents.java

@@ -0,0 +1,42 @@
+package io.avaje.config;
+
+import java.util.Collections;
+import java.util.List;
+
+final class CoreComponents {
+
+  private final ModificationEventRunner runner;
+  private final ConfigurationLog log;
+  private final Parsers parsers;
+  private final List<ConfigurationSource> sources;
+
+  CoreComponents(ModificationEventRunner runner, ConfigurationLog log, Parsers parsers, List<ConfigurationSource> sources) {
+    this.runner = runner;
+    this.log = log;
+    this.parsers = parsers;
+    this.sources = sources;
+  }
+
+  CoreComponents() {
+    this.runner = new CoreConfiguration.ForegroundEventRunner();
+    this.log = new DefaultConfigurationLog();
+    this.parsers = new Parsers();
+    this.sources = Collections.emptyList();
+  }
+
+  Parsers parsers() {
+    return parsers;
+  }
+
+  ConfigurationLog log() {
+    return log;
+  }
+
+  ModificationEventRunner runner() {
+    return runner;
+  }
+
+  List<ConfigurationSource> sources() {
+    return sources;
+  }
+}